T Cell Help to B Cells in Germinal Centers: Putting the Jigsaw Together

Abstract

The germinal center (GC) reaction supports the processes of affinity maturation and class switching in B cells that result in long-lasting humoral immunity. CD4⁺ T follicular helper cells (Tfh) participate in the GC reaction to help B cells. However, recent studies highlight the heterogeneity of CD4⁺ T cells in GCs, which confounds the understanding of Tfh cells. Based on many recent studies, we have tried to form a working model on the niche of Tfh cells in GCs. We have also addressed whether Tfh cells are a distinct lineage and how they may be generated to help B cells.

Keywords :

• follicular T helper cells
• B cells
• germinal centers
• T cell subsets

ACKNOWLEDGMENTS

We profusely thank Dr. Shiv Pillai, Harvard Medical School, Boston, for discussions and comments. UG and SBC are recipients of fellowships from the Department of Biotechnology (DBT) and Council of Scientific and Industrial Research (CSIR), New Delhi, respectively. We also thank CSIR for financial support.