Publication:

Diversity of regulatory T cells in various immuno-physiological conditions

Background Regulatory T cells (Tregs) play an active role in abrogating immune responses during microbial infections and are thus essential to maintain immune homeostasis and self-tolerance. Aberrant expression of Tregs can lead to spectrum of manifestations from allergy, chronic infections to immunopathological conditions such as autoimmunity and cancer. It is critical to have a clear understanding about the Tregs biology before attempting any possible interventions in humans. This study was undertaken to analyze the differential expression of Tregs in various physiological conditions.

Methods Peripheral blood mononuclear cells (PBMCs) were extracted from normal human subjects (n=30), pregnant females (n=10), cord blood (n=10) and patients with various immunopathological conditions such as cancer (newly diagnosed non-Hodgkin’s lymphoma, n=10), autoimmune conditions such as (type 1 diabetes mellitus-T1DM, Hashimoto’s disorder, and other autoimmune disorders, n=10 each) and in donor grafts (n=10) following allogeneic hematopoietic stem cell transplant. Flow cytometry was performed to detect CD4+CD25+FOXP3+Tregs and CD4+CD25+CD127dim/-Tregs.

Results The levels of Tregs was found to be were significantly higher in cord blood from newborn infants, patients with T1DM and Hashimoto’s disorder. In addition, the difference in Tregs level in pregnant females, patients with stem cell transplants, non-Hodgkin’s lymphoma and other autoimmune disorders were not significant.

Conclusions Till date, no comparative study was available about the status of Tregs population in normal and different physiological conditions from India. This is the first preliminary quantitative analysis of association of Tregs with different disorders. A clear cognizance of Tregs biology among various physiological conditions will be vital for targeting of these cells for any possible therapeutic modalities.