Skin, serving as the body’s largest multifunctional barrier organ, provides essential protection for internal organs against environmental threats. Numerous endogenous pathological conditions and exogenous mechanical insults that compromise cutaneous tissue integrity or architecture can result in skin wounds, posing significant life-threatening risks to patients.1 Current epidemiological estimates indicate that dermatological pathologies affect approximately one-third of the global population, with wound management imposing substantial healthcare and socioeconomic burdens on both individuals and societies.2 Beyond localized wound characteristics (including depth, dimensions, and infection status), the healing trajectory may be further complicated by systemic factors such as immunological/nutritional deficiencies, advanced age, and chronic comorbidities.3 Despite extensive research efforts to enhance cutaneous wound healing, current clinical therapeutic strategies frequently demonstrate suboptimal efficacy across diverse clinical scenarios.
Biological ingredients possess the remarkable capacity to alter the cellular milieu and impart a diverse array of stimuli to host cells. Such active ingredients can exist as biological vesicles, synthetic bioactive vesicles, or live host cells. Cell therapy entails the utilization of transplanted cells to participate in various stages of wound healing, suppress excessive local immune responses, secrete diverse growth factors, facilitate vascular regeneration and wound re-epithelialization, and ultimately expedite wound closure and enhance the quality of wound healing.4 Nevertheless, their sustained clinical application has been hindered by immune rejection, non-biocompatible scaffold materials, cell sources and processing techniques, maintaining cell viability throughout therapy, individual patient variations, and exorbitant costs.5 Biological vesicles are secreted by cells, such as extracellular vesicles, and their importance in intercellular signaling communication has been firmly established. The events mediated by biological vesicles are associated with cell proliferation, differentiation, migration, apoptosis, immunomodulation, and the ability to cross barriers, such as plasma membrane, blood-brain barrier, and gastrointestinal tract.6–8 Therefore, biovesicles are considered a highly promising alternative strategy for cell therapy.9,10 These biological vesicles have been shown to retain the efficacy of the maternal cells while avoiding problems of immune rejection, tumorigenicity, teratogenicity, and ethical perspectives. Biological vesicles are ideally suited for long-term storage due to their high stability, controllability for monitoring and assessing the healing process, precision for quantitative application, and high efficiency for enriching the wounded area.11,12 Furthermore, biological vesicles contain a wide range of proteins and RNAs that can stimulate cell migration, proliferation, and differentiation; they can also speed up the formation of blood vessels and extracellular matrix reconstruction by inducing inflammation in the wound; and they can function as a dual agent, promoting wound healing while preventing the formation of epileptic scars, which has good potential for regeneration and repair.13
Bioinspired vesicles represent a class of artificial or semi-artificial nanoscale carrier systems engineered through biomimetic principles, deriving structural and functional characteristics from natural biological vesicles (eg, extracellular vesicles, liposomes).14 Their core design paradigm involves constructing functionalized vesicles with tailored biocompatibility, targeting specificity, or environmental responsiveness by mimicking critical biological membrane features - including compositional architecture, dynamic behaviors, and signaling mechanisms of cellular/organelle membranes.15 Compared to natural counterparts, these engineered systems exhibit superior performance in structural stability, drug-loading efficiency, and functional programmability, while effectively circumventing inherent challenges of natural vesicles such as source-dependent heterogeneity and scalability limitations in manufacturing.16 Bioinspired vesicles show significant market potential for application in the field of wound healing. In terms of production cost economics, the donor is widely available and inexpensive. With the continuous optimization of the preparation process, the application of genetic engineering and chemical modification technology has increased the vesicle yield and reduced the production cost. From the point of view of market application value, bio-inspired vesicles have more significant therapeutic effects and a wider application scope. With the improvement of the quality of wound healing and the increasing demand for new therapeutic technologies, bio-inspired vesicles have a huge market potential, and their wide application will promote the development of related medical devices and pharmaceuticals and expand the market space.
The challenges such as large-scale manufacturing, purification, modification, drug loading, storage, and heterogeneity persistently impede the further transformation of biological vesicles. To circumvent the limitations of biological vesicles, synthetic nanoparticles that mimic the therapeutic properties and drug delivery capabilities of biological vesicles—such as their nanoscale size, targeting ability, cellular internalization efficiency, and stability—have been made possible by biomimetic nanotechnology in recent years. These nanoparticles also make up for the drawbacks of biological vesicles, which include low yields, complicated isolation and purification procedures, and high costs.17 The advancement of embedded sensors and intelligent materials has driven the evolution of smart dressings for wound management, with these integrated sensors and responsive materials demonstrating the capability to detect specific biological triggers (eg, pH variations, temperature fluctuations, enzymatic activities) through precise physicochemical responses, thereby offering innovative platforms for efficient delivery of bioactive vesicles.18 On the other hand, there are still many challenges that need to be addressed before active vesicles can be used in clinical applications.19 The production process of active vesicles needs to be further optimized to increase yield and reduce cost. Also, their stability and biodistribution in vivo need to be studied in greater depth to ensure their safety and efficacy during treatment. In addition, the long-term storage conditions and transport requirements of active vesicles need to be clarified to ensure their feasibility and convenience in practical applications. In view of the significant advantages of bioinspired vesicles in terms of biocompatibility, therapeutic efficacy, drug delivery efficiency, production cost control, and market potential, bioinspired vesicles are becoming increasingly important in wound healing and other medical applications, and have become a preferred option that has attracted a great deal of attention.
We first systematically reviewed cutting-edge research on diverse sources and isolation techniques of biological vesicles, while highlighting the distinct characteristics of the associated strategies. Furthermore, this comprehensive analysis examines recent advancements and current limitations of bioinspired vesicle systems engineered through multiple technologies for wound healing enhancement. Finally, we synthesized data from ongoing and completed vesicles-based clinical trials, identifying multifaceted challenges in clinical translation. Our analysis suggests that enhanced mechanistic understanding of both biological and bioinspired vesicles could yield novel therapeutic candidates and precision strategies for advanced wound management.
The Origin of Biological VesiclesBiological vesicles exhibit diverse biological origins encompassing mammalian organisms, botanical species, and specialized biological groups, each demonstrating unique therapeutic advantages in wound management due to their distinct compositional profiles and functional characteristics.20,21 Mammalian-derived vesicles have emerged as pivotal therapeutic agents for complex wound pathologies (eg, diabetic ulcers, burn injuries) through their superior bioactivity and precise regulatory capabilities, while plant- and insect-derived counterparts address critical gaps in conventional therapies via their distinctive components (antioxidant molecules, antimicrobial peptides) and enhanced delivery efficiency.22 This section systematically catalogs currently available vesicle sources, investigates their mechanisms of action, and elucidates their distinct therapeutic benefits in wound healing processes (Figure 1).
Figure 1 Natural sources of biological vesicles. The figure was created with https://app.biorender.com/.
Animal CellsAnimal-derived biological vesicles originate from diverse cellular sources, with mesenchymal stem cells (MSCs) representing the most extensively characterized source to date.23 MSC-derived EVs (MSC-EVs) have garnered significant scientific attention due to their demonstrated therapeutic potential in tissue regeneration processes.24 Notably, cutaneous cellular components (keratinocytes and fibroblasts) and immune effector cells (macrophages) constitute additional biologically significant EV sources.25 This section systematically examines the differential functional profiles and therapeutic characteristics exhibited by these cellularly derived EVs during wound healing progression.26
Resident Skin CellsSkin cell-derived biological vesicles have emerged as native therapeutic agents in wound repair, distinguished by their direct cellular origin, multifunctional efficacy, and inherent compatibility with the wound microenvironment. Unlike vesicles from non-cutaneous sources, these biological vesicles originate from peri-wound cells, demonstrating superior microenvironmental adaptation and efficient cellular uptake. Scientific consensus confirms their wound-healing enhancement through four coordinated mechanisms: promoting cellular proliferation/migration, accelerating angiogenesis/re-epithelialization, modulating immune responses, and reducing scar formation. Specifically, keratinocyte-derived exosomes mitigate pro-inflammatory cytokine release (eg, TNF-α, CD74, and inducible nitric oxide synthase [iNOS]) while enhancing anti-inflammatory mediator synthesis, thereby controlling macrophage migration/activation.27 Fibroblast-derived exosomes promote aged skin wound healing through miR-125b release and fibroblast-to-myofibroblast transition induction.28 During tissue remodeling, exosomes from fibroblasts and endothelial cells regulate extracellular matrix (ECM) synthesis, maturation, and reconstruction.29,30 Additionally, exosomes from keratinocytes and fibroblasts prevent scar formation by transferring fibroblast-developmental miRNAs to myofibroblasts and modulating ECM deposition.9,31 As a result, skin resident cells are considered to be one of the reliable sources of biological vesicles.
The synergistic integration of biomaterials with skin-derived biological vesicles presents a transformative strategy for wound repair, leveraging material engineering to optimize vesicle stability, targeted delivery efficiency, and functional durability, thereby maximizing therapeutic potential.32 To address the challenge of biomolecular leakage—a critical limitation in conventional delivery systems—researchers developed microneedles (MNs) encapsulating tazarotene and exosomes for localized wound application, demonstrating their dual functionality in spatiotemporally controlled release.33 Experimental validation revealed that this MN-based platform significantly enhances cellular proliferation, migration, and angiogenesis across both in vitro and in vivo models, with murine wound studies confirming synchronized delivery of therapeutic agents and exosomes.34 The elucidation of molecular mechanisms underlying skin-derived biological vesicles remains a pivotal research focus,35 with metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) identified as a critical regulatory factor functioning through binding interactions with miR-124 or miR-378a-8 to exert therapeutic effects and promote tissue regeneration.36 Building on this discovery, researchers engineered MALAT1-overexpressing exosomes from human keratinocytes, demonstrating that this combinatorial strategy not only activates MFGE8 via suppression of miR-1914-3p but also enhances macrophage phagocytic capacity (Figure 2), thereby establishing a dual-axis repair mechanism integrating molecular silencing with immunomodulatory functions.37 However, skin-derived biological vesicles face unique challenges in clinical translation for wound therapy. Primary skin cells demonstrate limited in vitro expansion efficiency and accelerated senescence under conventional two-dimensional (2D) culture conditions, resulting in vesicle yields significantly lower than those from mesenchymal stem cells.38 Psoriasis patient-derived vesicles may exacerbate inflammatory cascades, necessitating stringent donor screening or compositional modification.39 Furthermore, the absence of FDA-established quality control metrics specific to skin-derived vesicles underscores the urgent need to develop quantitative standards based on skin-specific biomarkers such as keratin 14 (KRT14) and loricrin (LOR).40
Figure 2 KCs -Exo carrying MALAT1 promoted wound healing in mice with diabetes mellitus. (A) Representative images of full thickness defects in mice at days 0, 3, 7, 14, and 21 days postoperatively. (B) Wound healing closure rates were calculated among the different groups using the ImageJ software. (C) H&E staining among the different groups at day 14, Scale bar: 200μm. (D) Masson’s trichrome staining among the different groups at day 14, Scale bar: 20μm. (E) Representative immunohistochemical images of CD31, Scale bar: 20μm. (F) Representative immunohistochemical images of vascular endothelial growth factor (VEGF), Scale bar: 20μm. (G and H) Relative protein expression of Collagen I, Cd31, Smad3, Tgfb1, Mfge8, Vegf determined by Western blot analysis. *p < 0.05, **p < 0.01 versus the control group; #p < 0.05 versus the KCs-Exo oe-NC group. Measurement data were expressed as mean ± SD. Comparison among multiple groups was conducted using one-way ANOVA, followed by Tukey’s post hoc test. (A–H) adapted from Kuang L, Zhang C, Li B, Deng H, Chen R, Li G. Human keratinocyte-derived exosomal MALAT1 promotes diabetic wound healing by upregulating MFGE8 via microRNA-1914-3p. Int J Nanomed. 2023;18:949. © 2023 The Author(s). This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, 3.0) License.37
Mesenchymal Stem CellMesenchymal stem cells (MSCs) are multifunctional, self-renewing cells that can secrete growth factors or differentiate into skin cells to enhance proliferation and facilitate tissue healing.41,42 Macrophage polarization, myofibroblast formation, and extracellular matrix reconstitution are all influenced by a variety of cytokines secreted by MSCs, including insulin-like growth factor-1 (IGF-1), vascular endothelial growth factor (VEGF), transforming growth factor-β (TGF-β), MMP-1, keratinocyte growth factor, and type I collagen.43,44 Because of their low immunogenicity, ease of storage, and highly efficient biological activity, MSC-derived exosomes, or MSC-exos, have drawn the attention of more researchers in light of the limited number of endogenous MSCs present during wound self-repair and the numerous adverse events that occur during MSC transplantation.45 Adipose-derived stem cells (ADSCs), bone marrow-derived mesenchymal stem cells (BMSCs), human umbilical cord mesenchymal stem cells (hUC-MSCs), and other stem cell types serve as viable mesenchymal stem cell (MSC) sources, all demonstrating therapeutic potential in diabetic wound healing, inflammatory wound repair, and keloid formation.46,47
Comparative analyses of MSC sources have revealed that human ADSCs (hADSCs) exhibit superior longevity, proliferative capacity, and resistance to senescence compared to BMSCs, therefore constituting the preferred biological vesicle source.48 In foundational studies, the application of hADSC-derived exosomes (hADSC-Exos) encapsulated in thermosensitive PF-127 hydrogel demonstrated enhanced wound closure rates in murine models.49 Furthermore, extensive evidence indicates that preconditioning strategies can amplify the paracrine activity of MSCs, exemplified by melatonin-pretreated MSC-derived exosomes (MT-Exo), which suppress excessive inflammation, stimulate angiogenesis and collagen deposition, and ultimately accelerate diabetic wound healing.50 The combinatorial use of MSC-derived vesicles from multiple sources presents synergistic advantages, capitalizing on their distinct molecular profiles. Researchers developed an innovative dual-crosslinked hydrogel composed of sericin and fibroin, co-loaded with platelet-rich plasma exosomes (PRP-Exo) and MSC-derived exosomes (MSC-Exos), which accelerated diabetic wound repair through coordinated upregulation of growth factor (GF) expression while downregulating matrix metalloproteinase-9 (MMP-9), thereby promoting angiogenesis, re-epithelialization, and anti-necrotic effects (Figure 3).51
Figure 3 Schematic illustration of (A) the synthetic process for dual-crosslinked hydrogels (SP@PRP, SP@PRP, and SP@PRP) and their use as diabetic wound dressings; (B) Factor XIIIa catalyzes a chemical reaction resulting in insoluble fibrin highly covalently crosslinked through glutamine and lysine residues; (C) Ca+2-silk protein interactions in SP@PRP activated with calcium gluconate, and (D) formation of exosome-loaded genipin-crosslinked silk protein hydrogels. (A–D) adapted from Bakadia BM, Ahmed AAQ, Lamboni L, et al. Engineering homologous platelet-rich plasma, platelet-rich plasma-derived exosomes, and mesenchymal stem cell-derived exosomes-based dual-crosslinked hydrogels as bioactive diabetic wound dressings. Bioact Mater. 2023;28:74. © 2023 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. CC BY-NC-ND 4.0.51
In vivo, double-cross-linked hydrogels accelerate wound healing by upregulating the expression of growth factors (GFs), downregulating the expression of matrix metalloproteinase-9, and promoting anti-NETotic actions, angiogenesis, and re-epithelialization. Recent research attention has extended to specialized bio-derived vesicles generated under specific physiological conditions. Notably, unlike exosomes, apoptotic bodies inherently possess dual signaling capabilities - employing “find-me” signals (eg, chemokine CX3CL1) and “eat-me” signals (eg, phosphatidylserine exposure) to recruit macrophages for targeted phagocytosis.52 Building upon these mechanisms, researchers have successfully developed ABs@GMSs through integrated liquid-phase microfluidic technology and biosynthetic engineering, creating an injectable localized biomaterial comprising biodegradable microspheres and releasable apoptotic vesicles.53 In rat models of chronic diabetic wounds, ABs@GMSs demonstrated superior efficacy in macrophage polarization and wound closure compared to conventional treatments (Figure 4).
Figure 4 AB@GMSs induce the polarization of M2 macrophages and promote angiogenesis during wound healing. *p < 0.05. Data are expressed as mean ±SEM. (A–K) adapted from Mao J, Qian S, Zhao Q, et al. Balancing macrophage polarization via stem cell-derived apoptotic bodies for diabetic wound healing. Med. 2024;5(2):148. © 2024 The Author(s). Published by Elsevier Inc. Creative Commons CC-BY-NC-ND.53
With the advancement of research and clinical experience, clinical trials investigating MSC-Exos have demonstrated a progressive annual increase. In a recent clinical trial (NCT05475418), hADSC-Exos were isolated and applied in wound therapy research, though experimental outcomes remain pending publication. Furthermore, Exogenus Therapeutics (Portugal) is developing ExoWound, a therapeutic product combining extracellular vesicles (EVs) from human umbilical cord blood mononuclear cells (Exo-101) with sustained-release hydrogel to modulate release kinetics, achieving threefold EV yield enhancement for wound healing applications. Despite these advancements, MSC-derived biological vesicles still encounter unique clinical translation barriers in wound management, particularly the marked functional heterogeneity observed among vesicles originating from different tissue sources (bone marrow, umbilical cord, adipose). Nevertheless, MSC-derived vesicles undeniably constitute a pivotal component in future clinical strategies for cutaneous injury repair.
Immune CellsThe wound healing process typically involves infection and tissue damage triggering immune responses that recruit neutrophils, macrophages, and lymphocytes to the injury site, facilitating wound bed clearance and tissue repair.4,54 Immune cell-derived biological vesicles demonstrate unique advantages in wound regeneration through their inherent immunomodulatory capacities. Specifically, neutrophil-derived EVs (N-EVs) directly eradicate pathogens via myeloperoxidase while mitigating inflammatory storms through let-7 miRNA-mediated TLR4 pathway inhibition, with their spatiotemporal recruitment dynamics proving particularly advantageous for acute wound intervention.55 Specifically, macrophage-derived EVs (M-EVs) exhibit dual functionality based on M1/M2 phenotypic polarization.56 M1-EVs eliminate pathogens via pro-inflammatory mediators like TNF-α, while M2-EVs promote collagen deposition through TGF-β, with engineered miR-21 loading further enhancing their anti-inflammatory and pro-angiogenic effects.57
Recent breakthroughs address diabetic wound complexities through hydrogel-based portable bioactive ink technology (PAINT), which significantly enhances macrophage M2 polarization and endothelial angiogenesis via M2-exosome (M2-Exos) delivery, achieving over 50% improvement in diabetic wound closure rates.58 Mechanistic studies reveal monocytes’ critical regulatory role:59 monocyte deficiency induces pathological leptin overproduction causing vascular hyperdilation at infection sites, thereby delaying healing and exacerbating scarring, whereas polynuclear cells counterbalance this through ghrelin-mediated suppression of leptin-induced vascular hyperplasia while promoting collagen alignment and epithelial regeneration.60 Immune cell precision regulation further inhibits scarring, exemplified by M2-EVs upregulating TGF-β3 and miR-29b to reduce type I collagen deposition while maintaining skin elasticity. Innovative research on re-epithelialization demonstrates dendritic epidermal T cells (DETCs) regulate epidermal stem cell (EpSC) proliferation through exosomal communication:61 Tcrδ-knockout models show 40% EpSC population reduction and re-epithelialization delay upon DETC exosome depletion, while exogenous DETC-EV supplementation restores EpSC function via Wnt/β-catenin pathway activation. Moreover, the integration of photothermal therapy with MN carriers expands therapeutic dimensions through localized thermal effects that suppress inflammatory cytokine storms, while enabling deep transdermal delivery of EVs via microneedle arrays, demonstrating multimodal regenerative potential in infected wounds62 (Figure 5).
Figure 5 (A) Schematic illustration of MEs@PMN for diabetic wound healing. (B) MEs@PMN for treating diabetic wound based on anti-inflammation and angiogenesis promotion. (A and B) adapted from Zeng J, Sun Z, Zeng F, Gu C, Chen X. M2 macrophage-derived exosome-encapsulated microneedles with mild photothermal therapy for accelerated diabetic wound healing. Mater Today Bio. 2023;20:100649. © 2023 The Authors. Published by Elsevier Ltd. license.63
The clinical translation of immune cell-derived biological vesicles remains in early exploratory stages, with allogeneic compatibility issues posing unique translational challenges distinct from other cell-derived EVs. Immune cells (eg, macrophages, dendritic cells) inherently exhibit heightened immunological activity, with their secreted EVs carrying parent cell-specific antigen-presenting molecules (MHC-I/II) on surface membranes, potentially triggering recipient immune rejection. For instance, unmodified dendritic cell-derived EVs (DC-EVs) have been shown to induce CD8+ T cell activation and IgG antibody production in murine allotransplantation models, resulting in an 80% EV clearance rate within 24 hours. Further complicating this landscape, immunogenicity varies substantially across EV subtypes: activated M1 macrophage-derived EVs demonstrate elevated surface expression of CD40 and CD86 co-stimulatory molecules compared to M2-EVs, exhibiting greater propensity for host T cell activation, while neutrophil-derived EVs may trigger alternative complement pathway activation through myeloperoxidase enrichment.
Other CellsIn addressing the critical challenge of low yield in vesicle production for regenerative applications, researchers have systematically explored alternative biological sources with enhanced productivity and accessibility. Oral mucosa has emerged as an ideal candidate for cell sheet engineering due to its unique regenerative properties, demonstrating scarless healing characteristics analogous to fetal wound repair mechanisms,64–66 with subsequent studies utilizing in vivo wound models to validate the pro-regenerative potential of exosomes derived from oral mucosal epithelial cells (OMECs).67 Concurrently, placental amniotic membrane serves as a prominent source of human amniotic epithelial cells (hAECs), which offer advantages including high yield extraction efficiency, low immunogenicity, and non-tumorigenic properties - researchers have successfully isolated high-purity exosomes (hAECs-Exos) from this source,68 demonstrating their capacity to accelerate wound healing through fibroblast activation and angiogenesis stimulation via PI3K-Akt-mTOR pathway modulation.69 Furthermore, activated platelets have been shown to enhance tissue repair through dual mechanisms of angiogenesis promotion and cellular proliferation stimulation,70 while plant-derived resveratrol, a non-flavonoid polyphenolic compound from Vitis vinifera, exhibits complementary therapeutic effects by reducing inflammatory responses and promoting vascularization during cutaneous wound healing. This pharmacological synergy has been strategically harnessed through the development of a composite hydrogel incorporating both platelet-derived extracellular vesicles (PDEVs) and mesoporous silica nanoparticle-loaded resveratrol (MSN-Res),71 creating a multifunctional therapeutic platform that simultaneously addresses angiogenesis enhancement and inflammation regulation (Figure 6).
Figure 6 Schematic diagram of GelMA/SFMA/MSN-RES/PDEVs hydrogel preparation and application. (A) Schematic of the modification of the gelatin molecule with MA. (B) Schematic modification of a silk fibroin molecule with GMA. (C) Schematic showing the preparation of GelMA/SFMA/MSN-RES/PDEVs hydrogels used as a dressing for wounds in a diabetic mouse model. PDEVs were drawn using Figdraw (www.fgdraw.com). Figure adapted with permission Zhu W, Dong Y, Xu P, et al. A composite hydrogel containing resveratrol-laden nanoparticles and platelet-derived extracellular vesicles promotes wound healing in diabetic mice. Acta Biomater. 2022;154:212. © 2022 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.71
Vesicles of Body Fluid OriginBiological vesicles constitute ubiquitous nanoscale communication systems within biological fluids such as bile, milk, saliva, urine, and blood, with their diagnostic and therapeutic exploitation leveraging the inherent accessibility of these liquid biopsy sources.72 Serum-derived exosomes (serum-Exos), the most prevalent and quantitatively dominant exosomal population in circulation, have demonstrated therapeutic efficacy in enhancing wound healing outcomes in diabetic patients. To elucidate the specific mechanistic contributions of serum-Exos to diabetic wound repair, researchers isolated substantial quantities of these nanovesicles from murine serum and administered them in vivo, revealing accelerated wound closure kinetics in diabetic murine models.73 Post-treatment analyses confirmed that serum-Exos upregulated CD31 expression, augmented fibronectin and collagen-α synthesis, and stimulated granulation tissue formation. Further mechanistic investigations identified enhanced serine-threonine kinase Akt phosphorylation in burn-injured dermal tissues following serum-Exos administration, suggesting activation of pro-regenerative signaling pathways.74 Emerging evidence posits that exercise-induced systemic adaptations involve the generation of “exercise factors” packaged into exosomes and released into circulation,75 with preclinical studies achieving successful therapeutic outcomes in cutaneous wound models through exercise-modulated exosomal delivery.76 Salivary exosomes (saliva-Exos) have garnered attention as optimal candidates for tissue regeneration due to their rich proteomic profile and growth factor content,77 with experimental validation confirming their pro-angiogenic capacity and wound-healing acceleration.78 Mammalian milk, a nutritionally complex biological fluid containing developmentally critical biomolecules,79 has been shown to promote fibroblast proliferation and collagen biosynthesis during dermal repair.80,81 Notably, milk-derived exosomes (mi-Exos) exhibit multifunctional regulatory properties encompassing immunomodulation, metabolic regulation, and neurodevelopmental support,82 establishing their potential as engineered therapeutic carriers for trauma management.83 Preclinical validation studies have consistently documented mi-Exos’ therapeutic efficacy in wound healing applications, further enhanced by their high yield and accessibility.84,85 Mechanistic evaluations revealed mi-Exos’ antioxidant capacity through free radical scavenging assays and modulation of key inflammatory mediators, while their scarless healing potential was attributed to selective upregulation of TGF-β3/TGF-β1 ratio in regenerating tissues.86 Fluid-derived biological vesicles face two predominant clinical translation barriers: heterogeneity control and isolation/purification technical constraints. The substantial heterogeneity of biological vesicles derived from bodily fluids manifests in dimensional variability (30–1000 nm), membrane protein compositional differences (eg, coexistence of exosomes and apoptotic bodies in plasma), and biomolecular cargo diversity, resulting in ambiguous functional definitions and inter-batch quality fluctuations (coefficient of variation >35% in critical biomarkers). Current isolation technologies are challenged by complex biological matrices containing serum protein aggregates and lipoprotein particles, with conventional ultracentrifugation methods causing structural damage to vesicle membranes while achieving suboptimal recovery rates of 5–25% as quantified by nanoparticle tracking analysis.87
Plant-Derived VesiclesBiomedical research has increasingly focused on plant-derived exosome-like nanovesicles (PENs) as natural intercellular communicators enriched with bioactive compounds, with systematic investigations now identifying key botanical sources including Triticum aestivum (wheat), Panax ginseng, Aloe barbadensis, Citrus paradisi (grapefruit), Vitis vinifera (grape), Citrus limon (lemon), Brassica oleracea (broccoli), Daucus carota (carrot), Malus domestica (apple), Zingiber officinale (ginger), Coffea arabica, and Citrus species through standardized multi-omics characterization.88–93 Functional validation studies demonstrate species-specific therapeutic advantages: Grapefruit-derived vesicles (GEVs) enhance HaCaT keratinocyte migration rates by 2.3-fold through coordinated upregulation of wound-associated genes (COL1A1, MMP9), proteins (fibronectin, laminin-5), and cytokines (IL-6, TGF-β1), as quantified via transcriptomic and proteomic profiling.94 Comparative analyses reveal PENs’ superior anti-inflammatory capacity and scalable production yields, positioning them as cost-effective alternatives for translational applications.95 Current research prioritizes systematic screening of plant species using high-content wound healing assays, with Triticum aestivum emerging as a lead candidate through multi-parametric evaluation—wheat PENs induce 2.1-fold fibroblast proliferation, accelerate angiogenesis (1.8-fold CD31+ vessel density increase), and upregulate 17 core healing-related genes (FGF2, VEGF-A, TIMP1) in full-thickness wound models.96 Parallel investigations of Panax ginseng demonstrate pleiotropic benefits beyond wound repair, including metabolic regulation and neurological protection,97 while ginseng-derived nanoparticles (GDNPs) exhibit dual therapeutic action—2.4-fold collagen deposition enhancement coupled with 57% IL-1β/IL-6 suppression in senescent skin models.98 These findings collectively establish PENs as a pharmacologically versatile platform offering enhanced biosafety, cost efficiency, and therapeutic multifunctionality for next-generation wound management strategies.
Other Sources of VesiclesThe natural world harbors diverse biological resources with vesicle-producing potential, among which Periplaneta americana L. (PA)—an environmentally resilient insect with historical medicinal applications—has demonstrated therapeutic relevance.99 PA-derived glycoproteins accelerate diabetic wound healing by modulating macrophage polarization dynamics, while exosome-like nanoparticles isolated from PA (PA-ELNs) exhibit tripartite therapeutic efficacy: enhanced re-epithelialization rates, autophagy pathway regulation, and anti-inflammatory activity, collectively contributing to improved diabetic wound closure.100 These findings underscore the broad phylogenetic distribution of vesicle sources and suggest that species-specific exosomal components may harbor unique therapeutic properties warranting systematic investigation.
Isolation of VesiclesVesicles are nowadays heavily used for direct treatment of diseases or delivery of multiple drugs.101 It is crucial to understand how to produce vesicles with high purity and throughput for later clinical applications.102 Numerous methods, including size exclusion chromatography, differential ultracentrifugation, ultrafiltration, immunoaffinity capture, polymer precipitation, and microfluidics, have been used to isolate vesicles—particularly exosomes—to date (Table 1).72,103 To choose the best separation techniques for future uses, a thorough analysis of factors including speed, efficiency, purity, dependability, automation level, and flexibility must be made. The benefits and drawbacks of widely used separation techniques are outlined in this section (Figure 7).
Figure 7 Methods for isolating biological vesicles (exosomes as an example). Numbers 1–6 in sequence are ultracentrifugation, ultrafiltration, immunoaffinity separation, volume exclusion chromatography, polymer precipitation, and microfluidics. The figure was created with https://app.biorender.com/.
Table 1 Overview of Isolation of Vesicles
UltracentrifugationUltracentrifugation (including differential centrifugation and density gradient ultracentrifugation) is one of the most widely used exosome separation methods, which is called the “gold standard” for vesicles separation.101 Because ultracentrifugation does not need expensive or complicated sample preparation, it is commonly utilized in exocrine processing.104 Regretfully, the ultracentrifugation technique yields only moderately pure samples and is time-consuming.105 Furthermore, exosomes may sustain mechanical damage as a result of repeated ultracentrifugation procedures. Apoptotic fragments, protein aggregates, and other non-exosomal contaminants are often eliminated using a number of purification processes used in differential ultracentrifugation.105,106 The purification process includes a low-speed centrifugation phase (300 to 400×g) to remove cell and apoptotic debris, a high-speed centrifugation phase (2000×g) to eliminate larger vesicles, and an ultra-fast centrifugation phase to harvest exosomes. Exosomes with a modest yield and purity have been produced via differential ultracentrifugation, as demonstrated by numerous tests. Although the above complex centrifugation process can ensure higher purity exosomes, it is difficult to avoid the loss of exosomes during this period.
A gradient medium, such as sucrose, is needed for density gradient ultracentrifugation in order to enrich vesicles in density-specific layers. Density gradient technique can extract exosomes in a given size range with higher purity but lesser yield when compared to differential ultrafast centrifugation. Nevertheless, density gradient ultracentrifugation is costly and unsuitable for the large-scale separation of exosomes because of the intricate structure of gradient media.
UltrafiltrationUsing commercial membrane filters with predetermined pore sizes, the ultrafiltration technique isolates biological fluids from vesicles.107 As a result, the separation is accomplished using the molecular weight and size. When compared to other methods, ultrafiltration is more straightforward and has a higher output.108 However, poor vesicle production will arise from vesicle buildup and pore blockage caused by vesicle retention in the pore canal.109 Damage may result from shear tension between the filter membrane and the vesicles brought on by the pressure of separation. To address these issues, techniques like membrane cleaning have been developed.
Direct current filtration (DFF) and tangential flow filtration (TFF) are the two categories into which the current vesicles ultrafiltration techniques can be separated. DFF has several drawbacks, including contaminated membranes and poor particle separation. DFF is also limited to the separation of small volume samples. The technique of tangentially moving sample fluid to filter the membrane and prevent cake formation or clogging is called TFF. TFF transfers the sample tangentially to the membrane as opposed to applying orthogonal pressure, as the aforementioned methods do. This technique prevents the buildup of particles on the membrane that causes blockage. TFF is gentler on the sample and can manage higher sample volumes than DFF. TFF will take longer to process, though, in order to obtain more pure exosomes.
Polymer Precipitation MethodVesicles and other tiny particles are precipitated from biological fluids through polymer precipitation, which modifies the solubility or dispersity of hydrophilic polymers.110 One of the most often used polymers for polymer precipitation is polyethylene glycol (PEG). After centrifugation, vesicles made of hydrophilic PEG with a certain molecular weight were separated from the incubated cell culture medium or bodily fluid.111 The researchers came up with an ideal plan by modifying the precipitation, salt, and polymer levels. Certain exosome extraction kits sold commercially have also used this technique.112 However, exosomes produced with this technique contain some protein impurities.113
Immunoaffinity SeparationThrough the interaction of vesicles’ surface proteins—such as CD9, CD63, and CD81—with particular antibodies, immunoaffinity isolation is able to collect vesicles.114 To facilitate separation, antibodies can be attached to a variety of support surfaces, such as magnetic beads, chromatographic substrates, plates, and microfluidic devices.115 To eliminate protein aggregates and other big particles, immunoaffinity capture is therefore frequently employed in conjunction with pretreatment techniques like volumetric exclusion chromatography or centrifugation. It goes without saying that immunoaffinity separation is a gentle and highly specialized technique that can keep vesicles’ biological activity mostly intact after separation. However, this technique is limited by the antibodies that can be supported, the application scope is limited, and the processing volume is small.116 Additionally, a longer incubation period is needed for immunoaffinity isolation. For instance, when used for separation, each magnetic Dynabead from Thermo Fisher needs to be incubated for 12 hours. Longer incubation times are caused by the magnetic beads’ large size (1.0–4.5 µm), limited mobility in solution, and low surface area to volume ratio. Using pH-or temperature-responsive magnetic nanoparticles can speed up this process. Because the nanoparticles have a larger surface-area-to-volume ratio and higher magneto electrophoretic mobility, after aggregation caused by changes in temperature or pH to allow for rapid magnetic separation. It is possible to shorten the periods of incubation and separation to a few minutes. Magnetism is also used in immunoaffinity techniques based on Raman scattering to separate and analyze vesicles. Molecules can be recognized by Raman scattering due to their distinctive chemical fingerprints. High sensitivity and specificity have been achieved in the detection of breast cancer in patient samples using magnetic surface-enhanced Raman scattering. The integration of characterisation and sample processing is essential in streamlining the therapeutic and diagnostic applications of exosomes and sets them apart from alternative immunoaffinity methodologies.
Volume Exclusion ChromatographyVesicles can be separated using a size-based technique called volumetric exclusion chromatography.117 This easy-to-use, low-cost vesicle separation technique prevents shear stress damage and does not require any specialized equipment. In general, this technique does a good job of preserving the integrity and structure of vesicles. It is frequently employed as a crucial stage in the purification of small EVs so that plasma impurities may be removed from them.118 To achieve high resolution particle size, processing parameters such as resin type, flow rate, column size, microbead loading, and system volume must be taken into account. To get a sample free of lipoprotein and protein contaminants, the material must first undergo ultracentrifugation or ultrafiltration. Size-exclusion chromatography, like other size-based separation methods, is not a practical way to separate exosomes from other particles of the same size.119 This issue might be resolved by combining immunoaffinity capture and separation techniques.120
Microfluidic TechnologyMicrofluidic technology is a high-throughput method, which can be compatible with a variety of vesicles separation methods.121 A high-throughput technique that can work with a range of vesicles separation techniques is microfluidic technology.122 Microfluidic devices offer a number of benefits.123 First, quicker separation times and reduced sample losses are made possible by microfluidic technology. Second, it can boost productivity and purity in a synergistic way when used in conjunction with other vesicle separation techniques. Furthermore, microfluidic devices can be expanded in accordance with actual needs and have a more compact structure than conventional separation devices. Microfluidic instruments are ideal for vesicle identification due to their small sample size and portability.
Nevertheless, there are certain issues with using microfluidic devices.124 First, samples may obstruct the path during examination, lengthening the time needed for identification and separation. Second, the method’s large-scale application is limited by the need for sophisticated equipment. In order to produce quick, effective, and high-purity vesicles separation procedures, researchers are attempting to integrate microfluidic devices with a variety of external pressures. These forces can be broadly classified into two categories: passive isolation techniques (membrane-based, column-based, and fluid dynamics) and active isolation techniques (electrical, centrifugal, and dynamical). Using acoustic dynamics as an example, it is widely accepted that larger particles in the sound field would experience stronger acoustic forces, causing them to separate from one another.125 Researchers combined acoustic flow and droplet rotation techniques to separate and identify exosomes.126 Experiments conducted later indicate that the gadget can handle data in less than a minute and achieve a high separation efficiency of 80–86%.
Vesicles have significantly advanced the fields of medication administration and non-invasive illness diagnostics and therapy because of their therapeutic potential and distinct biological activities. One of the main obstacles to vesicles’ therapeutic evolution in the last few decades has been their isolation.127 Currently, there are many established methods for separating vesicles that make use of cutting-edge technology like electricity, centrifugal force, microfluidics, and acoustics.128 Ultracentrifugation (UC), the most widely utilized separation technique, exhibits recovery rates significantly influenced by sample types and operational parameters. A systematic comparative study demonstrates that UC achieves exosome recovery rates below 30% from plasma, with high centrifugal forces potentially causing partial degradation of vesicular membrane proteins such as CD63.118 Immunoaffinity methods (eg, antibody-conjugated magnetic bead capture) achieve high-purity isolation (>90%) but incur substantial reagent costs (antibody consumption reaching hundreds of dollars per experiment) and risk compromising vesicle integrity during elution.129 Microfluidic platforms, despite their high-throughput processing capabilities and low shear stress characteristics, face clinical-scale implementation challenges: studies on inertial focusing chips reveal mandatory pre-filtration requirements for complex biological samples like serum to remove large particulate contaminants, accompanied by progressively increasing channel clogging rates during prolonged operation.130 Regarding scalability, UC maintains dominance due to equipment accessibility but struggles to meet therapeutic-grade dosage demands, while parallelized microfluidic designs (eg, multi-channel chips) theoretically enhance processing capacity yet require optimization of standardization protocols and cost-effectiveness in manufacturing.131 Hybrid strategies combining UC pre-concentration with microfluidic sorting have demonstrated improved recovery rates and purity profiles, though clinical translation necessitates rigorous GMP certification and large-scale validation.132
Design and Development of Biological VesiclesBioinspired vesicles demonstrate optimized biomedical application potential through the integration of biomimetic principles and engineering technologies,133 while preserving core functionalities of natural biological vesicles (eg, extracellular vesicles, exosomes).134 First, enhanced stability and controllability: Whereas natural vesicles exhibit fragile membrane structures susceptible to enzymatic degradation or oxidative damage with short in vivo circulation half-lives, bioinspired counterparts achieve extended circulation durations through synthetic lipid incorporation (eg, DSPC), polymer modification (eg, polyethylene glycol), or crosslinking strategies, coupled with environment-responsive materials (eg, pH-sensitive lipids, thermosensitive polymers) for targeted drug release at lesion sites.135 Second, breakthroughs in drug-loading efficiency and functional programmability: Natural vesicles typically exhibit drug-loading capacities below 10% due to endogenous content limitations and membrane permeability constraints, whereas bioinspired systems achieve 30%-50% loading efficiencies for small-molecule drugs, nucleic acids (eg, siRNA, mRNA), and proteins through electroporation, microfluidic manipulation, or membrane reconstitution techniques, enabling multi-drug co-loading and sequential release.136 Third, reduced immunogenicity and allogeneic risks: While natural vesicles (particularly xenogeneic sources) may carry donor-specific antigens or pro-inflammatory factors triggering immune clearance or toxicity, bioinspired variants minimize immunogenicity through purified membrane components (eg, non-target protein removal), surface ligand engineering (eg, CD47 overexpression for immune evasion), or fully synthetic material construction, thereby improving biocompatibility.137 Fourth, scalable manufacturing and standardization feasibility: Contrasting with natural vesicle production limited by cell culture conditions and batch-to-batch variability, bioinspired systems enable standardized large-scale manufacturing via microfluidic assembly, liposome extrusion, or membrane protein reconstitution technologies, meeting clinical-grade quality control requirements (eg, size uniformity, drug-loading consistency).15 Overall, it is anticipated that synthetic vesicles mimics would increase the effectiveness of bioactive compounds’ distribution to therapeutic targets while producing scalable preparation methods and desired results.138 The field of oncology medicines has extensively investigated this synthetic technique.139 The blood-brain barrier’s (BBB) poor drug penetration significantly reduces the effectiveness of treatment for glioblastoma multiforme (GBM). Bionic nanoparticles (NPs) embedded in GBM cell membranes have been used by researchers to successfully transport medications to GBM cells across the blood-brain barrier. In the meanwhile, a number of investigations have demonstrated that, in contrast to biological vesicles, synthetic vesicles offer larger yields, consistent efficacy, and possible therapeutic uses.140 Currently, there are three types of synthetic strategies: top-down, bottom-up, and biohybrid (Figure 8). We also provided a summary of the artificial vesicles here (Table 2).
Figure 8 Strategies for artificial synthesis of bionic vesicles. Number 1–3 in sequence are bottom-up, top-down, and biohybridisation strategies. A bottom-up approach would include developing larger, more complicated structures gradually by beginning with the assembly of smaller, simpler elements. Top-down procedures begin with larger biological structures, which are subsequently broken down into smaller pieces using different techniques to create smaller vesicles. Through the process of biohybridization, natural and synthetic vesicles can be combined to create vesicles. The figure was created with https://app.biorender.com/.
Table 2 Summarization of the Synthetic Vesicles
Bottom-UpA bottom-up approach would include developing larger, more complicated structures gradually by beginning with the assembly of smaller, simpler elements.148 This is comparable to the architectural construction process.149 Therefore, it is evident that bottom-up approaches necessitate a thorough comprehension of the essential elements of natural exosomes. Liposomes are believed to have exceptional biocompatibility because of their ability to replicate the membrane shape of exosomes or natural cells.150 These days, the focus of research is on adding lipids with certain compositions to exosome-like nanoparticles. Then, the necessary surface proteins are added to the manufactured lipid bilayers utilizing methods such as chemical biocoupling, simple incubation, and cell-free protein synt
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