In the previous study, we found that the levels of IL-21 in nasal polyps (NPs) were significantly increased and associated with polyp size and recurrence. However, it is unclear that the cell source of IL-21 and the regulation of IL-21 in NP tissues. In the present study, we isolated the lymphocytes from NP tissues, uncinate tissues and peripheral blood of patients with NPs. The cells were anal...

Upon encounter with antigen, CD4(+) T cells differentiate into effector T(h) subsets with distinctive functions that are related to their unique cytokine profiles and anatomical locations. One of the most important T(h) functions is to provide signals to developing B cells that induce specific and appropriate antibody responses. The major CD4(+) T cell subset that helps B cells is the T follicu...

BACKGROUND Ultraviolet B (UVB) induces multiple inflammatory and carcinogenic reactions. In skin, UVB induces to secrete several kinds of inflammatory cytokines from keratinocytes and also increases angiogenic process via the modulation of vascular endothelial growth factor (VEGF) production. Interleukin-21 (IL-21) is an inflammatory cytokine and produced by activated T cells. The biologic func...

B-cell responses are guided by the integration of signals through the B-cell receptor (BCR), CD40, and cytokine receptors. The common γ chain (γc)-binding cytokine interleukin (IL)-21 drives humoral immune responses via STAT3-dependent induction of transcription factors required for plasma cell generation. We investigated additional mechanisms by which IL-21/STAT3 signaling modulates human B-ce...

OBJECTIVE Interleukin-21 (IL-21) is a proinflammatory cytokine that has been shown to affect Treg/Teff balance. However, the mechanism by which IL-21 orchestrates alloimmune response and interplays with Tregs is still unclear. RESEARCH DESIGN AND METHODS The interplay between IL-21/IL-21R signaling, FoxP3 expression, and Treg survival and function was evaluated in vitro in immunologically rel...

Produced by CD4(+) helper T cells and natural killer T (NKT) cells, interleukin-21 (IL-21) performs broad regulatory functions on B cells, CD4(+) T cells, CD8(+) T cells, NK cells and NKT cells. Targeting IL-21 to enhance the immune system has attracted great interests in the development of vaccination, anti-infection and anti-tumor therapies. Administration of IL-21 in pre-clinical models is h...

T follicular helper (Tfh) cells help development of antibody responses via interleukin-21 (IL-21). Here we show that activated human dendritic cells (DCs) induced naive CD4(+) T cells to become IL-21-producing Tfh-like cells through IL-12. CD4(+) T cells primed with IL-12 induced B cells to produce immunoglobulins in a fashion dependent on IL-21 and inducible costimulator (ICOS), thus sharing f...