Regulatory T-cells (T-reg cells) play a crucial role in maintaining the peripheral tolerance through active suppression of cytotoxic T-cells. T-regs have become an emerging field of interest as their altered numbers and dysfunction can lead to devastating human diseases including various autoimmune diseases and various types of cancers. Dysfunction or deficiency of T-regs has been reported in several autoimmune diseases including type 1 diabetes, multiple sclerosis, systemic lupus erythematosus, myasthenia gravis, rheumatoid arthritis, vitiligo etc.

However, the generation of T-regs is considered as one of the major hurdles in eliciting potent antitumor immune responses in several cancers including cervical, ovarian, gastric, lung cancer, colorectal carcinoma and non-small cell lung cancer and cutaneous T-cell lymphoma etc. In addition, their role in infectious diseases (bacterial and viral infections) has been attributed. The link of T-regs with COVID-19 infection is an emerging topic to provide more insights on the role of T-regs in acute viral infections.

This Special Issue will address recent findings concerning the role of T-regs in the pathogenesis of autoimmune diseases, cancers, bacterial, and viral infections. Additionally, the issue will also include the current findings and animal model studies carried out for T-reg based therapeutic approaches for autoimmune diseases and cancers. Any specific COVID-19 disease and T-reg based original studies and review articles and other bacterial and viral infections will also be encouraged. Moreover, vaccine-induced effects on Tregs and probiotic interventions for inducing T-regs in autoimmune diseases will also be welcomed.

Potential topics include but are not limited to the following:

• Mechanisms of regulatory T-cells’ function
• Role of regulatory T-cells in the pathogenesis of autoimmune diseases
• Regulatory T-cell based therapeutics in autoimmune diseases
• Role of regulatory T-cells in the pathogenesis of cancer
• Regulatory T-cell based therapeutics in cancer
• Regulatory T-cells and viral infections (e.g., SARS-CoV-2, retroviral infections, etc.)
• Regulatory T-cells and bacterial infections (e.g., Mycobacteria, Listeria monocytogenes, and Bordetella pertussis, etc.)
• Animal model studies for the role of regulatory T-cells in autoimmune diseases, cancer, bacterial and viral infections
• Vaccine induced effects on the functioning of regulatory T-cells
• Probiotic interventions for T-reg induction in autoimmune diseases