Vitamin B1 is an essential survival factor for naïve B cells but not IgA-secreting plasma cells (120.9)

Abstract

Abstract It is generally accepted that dietary factors contribute in the regulation of various immunological functions. Among different kinds of dietary materials, vitamin families such as vitamin A, B6, B9, and D3 play critical regulatory roles for immune responses, but the immunological functions of the other vitamins remain largely unknown. Here, we demonstrate that vitamin B1, also known as thiamine, is an essential factor to keep naïve B cells but not IgA-secreting plasma cells. When mice were maintained with vitamin B1-deficient diet, IgM+ B220+ naïve B cells were significantly decreased in the spleen, mesenteric lymph nodes, and Peyer’s patches, while B220- CD138+ plasma cells secreting IgA antibodies were normally present in the small intestine. In agreement with this finding, despite the reduction of naïve B cells, levels of antigen-specific intestinal IgA responses were unchanged in mice receiving vitamin B1(-) diet after oral immunization with Choleratoxin. Similarly, IgA-secreting cells normally produced IgA even in the absence of vitamin B1 in vitro. These findings demonstrate a new immunological function of vitamin B1 at the different B cell stages.