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Biology subjects

Vats, B.

Publications and source records attributed to Vats, B..

2 recordsLinked to original sources

MAP hydrogel promotes revascularization of human ovarian graft and integration with the hypothalamic-pituitary axis in a mouse model of primary ovarian insufficiency

Ovarian tissue cryopreservation and autotransplantation (OTCT) is a crucial fertility preservation strategy for patients facing gonadotoxic cancer treatments, but its clinical success is hampered by ischemic injury and follicle loss following transplantation. This study aimed to enhance OTCT outcomes by employing microporous annealed particle (MAP) hydrogels to promote human ovarian graft revascularization. Unlike non-encapsulated tissue grafts, which exhibited early but transient and disorganized host vascular infiltration followed by regression, tissue grafts encapsulated in MAP hydrogels (OvaMAPs) demonstrated delayed yet organized and stable, long-term revascularization. OvaMAPs had significantly greater mouse CD31+ tissue area and vessel length after 3 and 6 weeks post-transplantation in ovariectomized immunodeficient mice compared to non-encapsulated grafts. By 20 weeks, both groups restored physiological estradiol levels (with OvaMAPs reaching 158 pg/mL) and suppressed follicle-stimulating hormone, confirming integration of the grafts with the hosts hypothalamic-pituitary axes. Notably, OvaMAPs achieved comparable endocrine function restoration with reduced estradiol variability, indicating more consistent graft function. In conclusion, MAP hydrogel encapsulation promoted long-term graft revascularization and vascular stability after OTCT, ultimately supporting consistent endocrine integration with host physiology.

bioengineering↗

Toxicity impacts on human adipose MSCs acutely exposed to Aroclor and non-Aroclor mixtures of PCBs.

PCBs accumulate in adipose where they may impact the growth and function of cells within the tissue. This is particularly concerning during adolescence when adipocytes expand rapidly. Herein we sought to understand how exposure to PCB mixtures found in U.S. schools affects human adipose mesenchymal stem/stromal cell (MSC) health and function. We investigated how exposure to Aroclor 1016 and Aroclor 1254, as well as a newly characterized non-Aroclor mixture that resembles the PCB profile found in cabinets, Cabinet Mixture, affects adipose MSC growth, viability, and function in vitro. We found that exposure to all three mixtures resulted in two distinct types of toxicity. At PCB concentrations >20 M, the majority of MSCs die, while at 1-10 M MSCs remained viable but display numerous alterations to their phenotype. At these sublethal concentrations, MSC rate of expansion slowed, and morphology changed. Further assessment revealed PCB-exposed MSCs had impaired adipogenesis and a modest decrease in immunosuppressive capabilities. Thus, exposure to PCB mixtures found in schools negatively impacts the health and function of adipose MSCs. This work has implications for human health due to MSCs role in supporting the growth and maintenance of adipose tissue. SYNOPSISPCB mixtures found in schools are toxic to human adipose mesenchymal stem/stromal cells, stunting their growth and altering their function in ways that could contribute to metabolic diseases.

pharmacology and toxicology↗