Table 6 Potential therapeutic applications of AF-EVs and AF stem cell/MSC derived EVs for various organs/tissues

Lungs

 Bronchopulmonary dysplasia [39]

AF-EVs

Neonatal rat model

Treatment reduced pro-inflammatory cytokine production and free-radical quenching, conserving alveolar growth

 Severe acute respiratory syndrome due to COVID-19 infection [41, 42, 122]

“Zofin” an FDA-approved AF-EVs therapeutic

Pilot clinical trials in severely ill COVID-19 patients

Treatment improved clinical status of participants and prevented disease progression

 Fetal lung underdevelopment (pulmonary hypoplasia) [117]

AFSC-EVs

Fetal rabbit model of pulmonary hypoplasia, ex-vivo fetal rat lungs grown for 72 h

Treatment altered gene expression in hypoplastic lungs and restored branching morphogenesis and alveolarization, promoting tissue maturation and cellular homeostasis

 Fetal pulmonary hypoplasia [65]

AFSC-EVs

Fetal rat pulmonary hypoplasia model

Treatment restored autophagy hypoplastic lungs by transferring EV-borne miRNA cluster miR-17∼92

 Fetal pulmonary hypoplasia [116]

AFSC-EVs

Lung explants from fetal rat pulmonary hypoplasia model

Treatment rescued airspace density and branching morphogenesis promoting differentiation of lung cells during both canalicular and saccular stages of fetal lung development

Brain/neuroinflammation

 Neonatal hypoxic encephalopathy [124]

AF-EVs

Neonatal hypoxic mouse model

Treatment eased hypoxic encephalopathy and enhanced angiogenesis, improved performance of the spatial memory

 Autism [125]

AF-EVs

Induced chick embryo autistic model

AF-EVs are effective drug delivery vehicles; successful unloading of sulforaphane resulted in gene expression regulation

 Ischemic stroke [49]

AFSC-EVs

Ischemia/reperfusion in-vitro model

Treatment activated pro-survival and anti-apoptotic pathways

 Alzheimer’s disease [50]

AFSC-EVs

Alzheimer’s disease neuron primary culture (murine)

Treatment reduced the progression of Amyloid-β-induced neuronal death and Alzheimer’s disease by improving neuron morphology and viability

 Alzheimer’s disease [58]

AFSC-EVs

In-vitro neuroinflammation model

Treatment reduced neuroinflammation, significantly recovering cells from neurotoxicity

 Neuromuscular junction integrity during muscle atrophy [103]

AFSC-EVs

Inducible in-vitro model of muscle atrophy

Treatment reduced disease progression, by protecting motor neurons from atrophic muscle cells-induced oxidative stress

Intestinal tissues

 Necrotizing enterocolitis [52]

AFSC-EVs

Inducible neonatal rat model

Treatment attenuated the bowel condition by activating Wnt/β-catenin signalling pathway

 Necrotizing enterocolitis [51]

AFSC-EVs

Premature rat pup model

Treatment reduced the incidence and disease severity of experimental necrotizing enterocolitis

 Necrotizing enterocolitis [100]

AFSC-EVs

Postnatal inducible mouse pup model

Treatment reduced intestinal injury and inflammation improving intestinal cell proliferation

 Necrotizing enterocolitis [101]

AFSC-EVs

Postnatal inducible mouse pup model

Treatment reduced intestinal injury, NEC score, systemic and ileal inflammation, and NEC-associated brain injury

 Inflammatory bowel disease [102]

AFSC-exosomes

Inducible in-vitro model of intestinal inflammation

Treatment reduced the severity of inflammation by downregulating inflammatory cytokines

Heart

 Cardiac muscle injury [47]

AFSC-EVs

Cardiotoxin injury mouse model

Treatment promoted tissue regeneration

 Cardiac fibrosis [129]

AFSC-EVs

Induced-cardiac fibrosis in vitro model

Treatment improved angiogenesis

 Cardiac injury [48]

AFSC-EVs

myocardial infarction rodent model

Treatment maintained the myocardial renewal with significant improvement of cardiac function

 Ischemia–reperfusion injury [60]

AFSC-EVs

Non‑recovery ischaemia–reperfusion injury rat model

Treatment showed significant benefits in cardio-protection and angiogenesis

 Myocardial infarction [64]

AFSC-EVs

Neonatal myocardial infarction mouse model

Developmentally immature AFSC-EVs are more effective in cardiomyocyte renewal and cell cycle re-entry

Skin

 Wound healing [104]

AFSC-EVs

Full-thickness skin-wounded rat model

Treatment accelerated the wound healing rate, enhancing regeneration of hair follicles, blood vessels and nerves. It also promoted cutaneous cell proliferation and collagen distribution

 Wound healing [105]

AFSC-EVs

Full-thickness skin-wounded rat model

Treatment significantly attenuated the scar formation and fibrosis

Ovaries

 Ovarian failure due to chemotherapy [46]

AFSC-EVs

Mice subjected to chemotherapy

miR-146a and miR-10a in murine AFSC-EVs showed a dominant effect on reducing the apoptosis in ovarian cells

 Ovarian failure due to chemotherapy [128]

AFSC-EVs

Inducible premature ovarian dysfunction rat model

Treatment restored total follicular counts, anti-Müllerian hormone levels, regular estrous cycles and conception; EV borne miRNA-21 acts by regulating PTEN and caspase 3 apoptotic pathways

 Ovarian failure due to chemotherapy [59]

AFSC-EVs

Mice subjected to chemotherapy

AFSC-EV borne miR-369-3p down-regulated apoptosis of ovarian granulosa cells

Skeleton

 Osteoarthritis [56]

AFSC-EVs

Inducible osteoarthritis rat model

Treatment produced near complete restoration of cartilage (positively correlated to TGFβ content in EVs) and polarized macrophages into EV-treated knee joints

 Osteoporosis [57]

AFSC-EVs

dexamethasone treated human pre-osteoblast cell line

Treatment maintained the precursor cell potential and viability of cells, delaying bone loss in steroid-related osteoporosis

Kidneys

 Alport Syndrome [127]

AFSC-EVs

Alport mice

Treatment reduced cellular damage, demonstrating glomerulus-targeted disease intervention

Testis

 Azoospermia [40]

AF-EVs

Non-obstructive azoospermia rat model

Treatment improved spermatogenesis and sperm quality, restoring testicular function in azoospermia rats

Organ damage

 Cystinosis [115]

AFSC-EVs

Ctns knockout mice

Treatment reduced lysosomal cystine accumulation in target cells