Functional human to mouse adipose tissue xenotransplantation

Area of Science:

• Metabolic research
• Immunology
• Tissue transplantation

Background:

• White adipose tissue (WAT) is a crucial endocrine organ producing metabolically active factors.
• Inborn errors of metabolism could potentially be treated by allogeneic WAT transplantation.
• The immunogenicity and metabolic compensation capacity of human WAT (HuWAT) require further investigation.

Purpose of the Study:

• To assess the potential of HuWAT transplantation to compensate for metabolic deficiencies.
• To evaluate the capacity of HuWAT to induce an allogeneic immune response in vivo.

Main Methods:

• Leptin-deficient, immunodeficient mice were transplanted with varying volumes (2.5 or 5 ml) of HuWAT.
• Metabolic parameters including body mass, hepatic steatosis, circulating leptin, food consumption, and plasma insulin were monitored.
• Immune response was assessed by co-transferring human mononuclear cells to evaluate WAT allograft rejection.

Main Results:

• HuWAT transplantation led to stable circulating human leptin levels and improved metabolic profiles, including reduced body mass gain and hepatic steatosis.
• Higher WAT volume (5 ml) correlated with significant reductions in food consumption and plasma insulin.
• Attempts to induce immune rejection via human mononuclear cells were ineffective, resulting in limited graft damage and transient leptin level reduction.

Conclusions:

• Human WAT transplantation effectively compensates for leptin deficiency and ameliorates metabolic dysfunction in vivo.
• HuWAT demonstrates low immunogenicity, as evidenced by the lack of significant allograft rejection.
• These findings support the therapeutic potential of HuWAT transplantation for metabolic disorders.