The T follicular helper cells (TFH) are a subset of CD4+ T cells specialized to regulate antibody responses.
The production of these cells is associated with the dendritic cells (DCs) and B cells. TFH cells help B cells
form germinal centers (GC) differentiate into memory and plasma cells (antibody-secreting cells) as
humoral responses. In addition, there is strong evidence that TFH cells play a pivotal role in the
development of long-lived humoral immunity. Molecular factors such as transcription factors, surface
receptors, cytokine and micro RNAs are involved in the formation of TFH cells. Such TFH cells are
diagnosed by transcription factor (BCL-6), surface marker expression (including CXCR5, PD-1, ICOS and
CD40L) and a unique cytokine production pattern (such as IL-21 and IL-6). Memory TFH cells,
accompanied by memory B cells, are known to be formed during antibody responses. It is now clear that
the precise control of TFH cells is critically important for both inducing the optimal affinity maturation of
antibody responses and preventing self-reactivity. Exclusive controls of TFH cell function and production
are essential for human health. However, it is important to note that excessive activities may lead to
autoimmune diseases, while reduced activity often results in immunodeficiency. It has also been shown
that TFH cells are associated with cancers such as angioimmunoblastic T-cell lymphoma (AITL), follicular
T-cell lymphoma (FTCL) and nonspecific Peripheral T-cell lymphomas (PTCLs). The biology of TFH cells,
including their differentiation and transcriptional regulation will be described in the present review.
Some of The developments of these cells in immunodeficiency diseases, autoimmunity and cancer will
also be taken into account.