Manoury-Schwartz B, Chiocchia G, Fournier C
INSERM U 283, Hôpital Cochin, Université René Descartes, Paris, France.
Eur J Immunol. 1995 Dec;25(12):3235-42. doi: 10.1002/eji.1830251206.
Native type II collagen (CII) is a high molecular-weight fibrillar molecule which induces a chronic polyarthritis in mice expressing the H-2q haplotype. The present study was initiated to analyze the processing and the presentation of this nonglobular protein by H-2q antigen-presenting cells (APC). Efficiency of presentation was assessed by the ability of antigen-pulsed APC to activate collagen-specific CD4+ T cell hybridomas. Fixation of APC or the presence of chloroquine completely blocked the reactivity of the T cell hybrids to native, denatured and cyanogen bromide (CB) degraded CII, thus indicating the requirement of intracellular processing for adequate presentation of CII peptides to T cells. In the presence of various processing inhibitors (brefeldin A, leupeptin and N-tosyl-L-phenylalanine chloromethylketone) stimulation of T hybrids by CII-pulsed APC was reduced, pointing to the need of newly synthesized class II molecules, the use of several intracellular compartments and the implications of different proteases in the generation of CII peptides. Peritoneal macrophages and, to a lesser extent, total spleen cells, presented native and denatured CII with higher efficiency than purified splenic dendritic cells, naive or even immune B cells from CII-primed mice. In contrast, these dendritic and B cells were fully competent to present intact ovalbumin to a specific T cell hybrid. The stimulation by dendritic cells and immune B cells was greater when CB peptides of CII were added instead of the native molecule. Similarly, the cleavage of CII was an absolute requirement for its presentation by epidermal cells and B cell lymphomas to the T cell hybridomas. Taken together, these findings emphasize the crucial role of intracellular processing for recognition of soluble CII, similar to most antigens. However, in contrast to ovalbumin, the size and fibrillar nature of the native CII molecule influences its capture by the APC, thus limiting the type of APC able to present this antigen.
天然II型胶原蛋白（CII）是一种高分子量的纤维状分子，可在表达H-2q单倍型的小鼠中诱发慢性多关节炎。本研究旨在分析这种非球状蛋白在H-2q抗原呈递细胞（APC）中的加工和呈递过程。通过抗原脉冲APC激活胶原蛋白特异性CD4+ T细胞杂交瘤的能力来评估呈递效率。APC的固定或氯喹的存在完全阻断了T细胞杂交瘤对天然、变性和溴化氰（CB）降解的CII的反应性，从而表明将CII肽充分呈递给T细胞需要细胞内加工。在存在各种加工抑制剂（布雷菲德菌素A、亮肽素和N-对甲苯磺酰-L-苯丙氨酸氯甲基酮）的情况下，CII脉冲APC对T杂交瘤的刺激减少，这表明需要新合成的II类分子、使用多个细胞内区室以及不同蛋白酶在CII肽生成中的作用。腹腔巨噬细胞以及程度较轻的全脾细胞，比纯化的脾树突状细胞、来自CII免疫小鼠的未致敏甚至免疫B细胞更有效地呈递天然和变性的CII。相反，这些树突状细胞和B细胞能够将完整的卵清蛋白充分呈递给特异性T细胞杂交瘤。当添加CII的CB肽而不是天然分子时，树突状细胞和免疫B细胞的刺激作用更大。同样，CII的裂解是其由表皮细胞和B细胞淋巴瘤呈递给T细胞杂交瘤的绝对必要条件。综上所述，这些发现强调了细胞内加工在识别可溶性CII中的关键作用，这与大多数抗原类似。然而，与卵清蛋白不同，天然CII分子的大小和纤维性质会影响其被APC捕获，从而限制了能够呈递这种抗原的APC类型。
