摘要

生發(fā)中心(GC)是次級淋巴組織的濾泡內(nèi)形成的對某些類型的免疫物質(zhì)和外來病原體做出反應的瞬態(tài)微結(jié)構(gòu)。成熟的GC由兩個功能不同的微環(huán)境組成，即暗區(qū)(DZ)和亮區(qū)(LZ)。DZ B細胞經(jīng)過快速克隆擴增，表達活化誘導的胞嘧啶脫氨酶(AID)，能靶向抗體基因可變區(qū)(IgV)基因發(fā)生超突變，從而產(chǎn)生一系列對抗原具有不同親和力的抗體突變體。在其他免疫細胞如T濾泡輔助細胞(Tfh)和濾泡樹突狀細胞(FDC)等的協(xié)助下，親和力高的GC B細胞選擇性地大量擴增，最終分化為記憶B細胞(MBC)和產(chǎn)生抗體的漿細胞(PC)。此外，LZ的GC B細胞也可能經(jīng)歷了AID介導的類別轉(zhuǎn)換重組。生發(fā)中心反應涉及多種免疫細胞，并受到譜系特異性轉(zhuǎn)錄因子的嚴格調(diào)控。這一單元我們將從細胞和分子信號角度出發(fā)，了解轉(zhuǎn)錄因子等yin'xGC產(chǎn)生和維持以及GC B細胞選擇的關(guān)鍵因素。

關(guān)鍵詞

#Germinal center B #T follicular helper cells #Follicular dendritic cell #Somatic hypermutation #Class switch recombination #Affinity selection

#生發(fā)中心B細胞?#T濾泡輔助細胞?#濾泡樹突狀細胞 #體細胞超突變 #類別轉(zhuǎn)換重組 #親和力成熟（親和力選擇）

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