Cutting edge: histamine receptor H4 activation positively regulates in vivo IL-4 and IFN-gamma production by invariant NKT cells.

Cutting Edge: Histamine Receptor H4 Activation Positively Regulates In Vivo IL-4 and IFN- Production by Invariant NKT Cells

Cutting edge: activation by innate cytokines or microbial antigens can cause arrest of natural killer T cell patrolling of liver sinusoids.

Natural killer T (NKT) cells are innate-like lymphocytes that rapidly secrete large amounts of effector cytokines upon activation. Recognition of alpha-linked glycolipids presented by CD1d leads to the production of IL-4, IFN-gamma, or both, while direct activation by the synergistic action of IL-12 and IL-18 leads to IFN-gamma production only. We previously reported that in vitro cultured dend...

Histamine regulates relevant murine dendritic cell functions via H4 receptor.

Histamine, produced by dendritic cells (DCs) or by other cells of the immune system, may have significant impact on DC activities. We investigated the influence of histamine and histamine H4 receptor (H4R) on some relevant functions of DCs. Histamine significantly decreased the antigen presentation capacity of splenic DCs, and this effect was reversed by a H4R antagonist. Furthermore, enhanced ...

Differential regulation of Th1 and Th2 functions of NKT cells by CD28 and CD40 costimulatory pathways.

Valpha14 NKT cells produce large amounts of IFN-gamma and IL-4 upon recognition of their specific ligand alpha-galactosylceramide (alpha-GalCer) by their invariant TCR. We show here that NKT cells constitutively express CD28, and that blockade of CD28-CD80/CD86 interactions by anti-CD80 and anti-CD86 mAbs inhibits the alpha-GalCer-induced IFN-gamma and IL-4 production by splenic Valpha14 NKT ce...

A key role for Itk in both IFN gamma and IL-4 production by NKT cells.

NKT cells rapidly secrete cytokines upon TCR stimulation and thus may modulate the acquired immune response. Recent studies suggest that signaling for development and effector function in NKT cells may differ from conventional T cells. The tyrosine kinase Itk is activated downstream of the TCR, and its absence in CD4(+) T cells results in impaired Th2, but not Th1 responses. In this study, we i...