Molecular forms of IgA produced by various lymphoid tissues--analysis using high speed liquid chromatography.

Molecular forms of immunoglobulin A (IgA) produced by cultured cells from various human lymphoid tissues were analyzed using high speed liquid chromatography (HLC). IgA secreted into culture media was easily separated into polymeric and monomeric forms by HLC. HLC has the advantages of high resolution, reproducibility, rapidity and technical simplicity in the separation of polymeric and monomeric IgA. Peripheral blood lymphocytes and cells from gut-associated lymphoid tissues, such as mesenteric lymph nodes or large bowel mucosa, secreted predominantly polymeric IgA, whereas lymphoid cells from bone marrow produced mainly monomeric IgA. Spleen cells and tonsillar cells produced nearly equal proportions of polymeric and monomeric IgA. These results suggest that with regard to IgA in serum, the polymer may originate from the gut-associated lymphoid tissues and the monomer may mostly derive from the bone marrow.