Farstad I N, Carlsen H, Morton H C, Brandtzaeg P
Laboratory for Immunhistochemistry and Immunopathology (LIIPAT), Institute of Pathology, University of Oslo, Rikshospitalet, Oslo, Norway.
Immunology. 2000 Nov;101(3):354-63. doi: 10.1046/j.1365-2567.2000.00118.x.
We compared B-cell phenotypes in Peyer's patches and solitary lymphoid follicles (organized gut-associated lymphoid tissue, GALT) with those in jejunal or ileal lamina propria. In situ, immunostaining showed that small B cells of naive [surface immunoglobulin D-positive (sIgD+) CD27-] and memory (sIgD+/- CD27+) phenotypes occurred almost exclusively in GALT, whereas the lamina propria contained only scattered sIgA+ CD27+ memory cells. In contrast, B-cell blasts and plasma cells negative for CD20 and often also for CD19 but with strong expression of CD38, CD27 and cytoplasmic IgA (cIgA), dominated in the lamina propria but were scarce in GALT. By flow cytometry, the proportion of dispersed CD19+ B lymphocytes varied from 4 to 42% among jejunal mucosal samples; between 5 and 50% of these were sIgD+, suggesting a variable contamination with GALT cells. B-cell blasts and plasma cells, identified by their large size and strong expression of CD38, were regularly found (25-35% of the total mononuclear cell population). Distinction between B-cell blasts and mature plasma cells was made by the presence or absence of human leucocyte antigen (HLA) class II molecules, CD45RA, CD19 and surface immunoglobulin. No CD19+ B cells outside GALT expressed CD5, but a very small portion of the lamina propria B-cell blasts were positive for CD28. Dispersed sIgA+ lamina propria cells expressed low levels of CD40, proliferated on CD40 ligation and constitutively secreted IgA in vitro. We concluded that the lamina propria B-cell compartment consists mainly of B-cell blasts and plasma cells but also has scattered, small sIgA+ cells that can proliferate in response to CD40 ligation and may therefore function as local memory cells for recall antigens.
我们比较了派尔集合淋巴结和孤立淋巴滤泡（有组织的肠道相关淋巴组织，GALT）中的B细胞表型与空肠或回肠固有层中的B细胞表型。原位免疫染色显示，幼稚型[表面免疫球蛋白D阳性（sIgD +）CD27 -]和记忆型（sIgD + / - CD27 +）表型的小B细胞几乎仅存在于GALT中，而固有层中仅含有散在的sIgA + CD27 +记忆细胞。相反，CD20阴性且通常CD19也阴性但CD38、CD27和细胞质IgA（cIgA）表达强烈的B细胞母细胞和浆细胞在固有层中占主导地位，而在GALT中则很少见。通过流式细胞术，空肠黏膜样本中分散的CD19 + B淋巴细胞比例在4%至42%之间；其中5%至50%为sIgD +，提示存在不同程度的GALT细胞污染。通过其大尺寸和CD38的强表达鉴定的B细胞母细胞和浆细胞经常被发现（占总单核细胞群体的25% - 35%）。通过人类白细胞抗原（HLA）II类分子、CD45RA、CD19和表面免疫球蛋白的存在与否来区分B细胞母细胞和成熟浆细胞。GALT外的CD19 + B细胞不表达CD5，但固有层中的一小部分B细胞母细胞CD28呈阳性。分散的固有层sIgA +细胞表达低水平的CD40，在CD40连接后增殖并在体外组成性分泌IgA。我们得出结论，固有层B细胞区室主要由B细胞母细胞和浆细胞组成，但也有散在的小sIgA +细胞，它们可响应CD40连接而增殖，因此可能作为回忆抗原的局部记忆细胞发挥作用。
