Immunohistochemical detection of co-localizing cytokine and antibody producing cells in the extrafollicular area of human palatine tonsils

Abstract

SUMMARYIn r(7rf> experiments have documented the role of cytokines in the regulation of ihc human humoral immune response. Which cytokines are operative in vivo and in which lymphoid compartment interactions between cytokinc-producing T cells and antibody-forming B cells occur is still unclear. For that reason we studied human tonsils using immunohislochemical techniques. In tissue sections from tonsils in a resting stage after recurrent tonsillitis we observed cells producing IL-1 a and tumour neerosis factor-alpha (TNF-a) whieh were exclusively localized in the mantle zone of the follicle and in the exlrafollicular area. Furthermore, a high frequency oi' interferon-gamma (IFN--/)-producing cells was delected in the extrafollicular area, but nol inside the follicles. Occasional IL-2-and IL-4-producing cells were found in ihc exirafollieular area, Immunohistochemieal detection of antibody isoiypes revealed that B cells, IgM-membrane-positive. were localized inside the follicles and manlle zones, whereas igD-membrane-positive cells were mainly found in the mantle zones of secondary follicles-In contrast, plasma cells producing IgG I 4 and IgA 1-2 were found in the extrafollicular area. No IgD and IgE antibody-forming cells were delected in tonsils, whereas IgM antibodyforming eells were detected in the extrafollicular area. The co-localization of cytokine-producing cells and antibody-forming cells in human tonsil suggests thai T B ceil interactions, required for B cell differentiation and isotype switching, take place in the extrafollicular area.Keywords cytokine-producing cells antibody-forming cells palatine tonsils isotype switching in situ human histochemistry

Specific strains of Streptococcus mutans, a pathogen of dental caries, in the tonsils, are associated with IgA nephropathy

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Yak (Bos grunniens) Tonsils: Morphological Description and Expression of IgA and IgG

“…In this study, the comparative expression levels of IgA and IgG mRNA and protein in yak tonsils showed that the expression levels of IgG was very significantly higher than that of IgA in the same tonsil. These results were consistent with the distribution of two ASCs in the palatine tonsils of pigs (Horter et al, ; Li et al, ), horses (Kumar and Timoney, ) and humans (Hoefakker et al, ; Boyaka et al, ; Nave et al, ) but were significantly different from the results in Bactrian camels (Jia et al, ). Furthermore, as a secondary lymphoid organ, the tonsils mainly secreted large numbers of IgG and a few IgA to promote mucosal immunity.…”

Clinical and immunological implications of increase in CD208+ dendritic cells in tonsils of patients with immunoglobulin A nephropathy

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