Trudeau Institute, Saranac Lake, New York, USA.
Nat Immunol. 2011 Nov 27;13(1):44-50. doi: 10.1038/ni.2172.
Mouse invariant natural killer T cells (iNKT cells) provide cognate and noncognate help for lipid and protein-specific B cells, respectively. However, the long-term outcome for B cells after cognate help is provided by iNKT cells is unknown at present. Here we found that cognate iNKT cell help resulted in a B cell differentiation program characterized by extrafollicular plasmablasts, germinal-center formation, affinity maturation and a robust primary immunoglobulin G (IgG) antibody response that was uniquely dependent on iNKT cell-derived interleukin 21 (IL-21). However, cognate help from iNKT cells did not generate an enhanced humoral memory response. Thus, cognate iNKT cell help for lipid-specific B cells induces a unique signature that is a hybrid of classic T cell-dependent and T cell-independent type 2 B cell responses.
小鼠天然不变型自然杀伤 T 细胞(iNKT 细胞)分别为脂质和蛋白质特异性 B 细胞提供同源性和非同源性帮助。然而,目前尚不清楚 iNKT 细胞提供同源性帮助后 B 细胞的长期结果。在这里,我们发现同源性 iNKT 细胞帮助导致了 B 细胞分化程序,其特征是滤泡外浆母细胞、生发中心形成、亲和力成熟和强烈的初级免疫球蛋白 G(IgG)抗体反应,该反应独特地依赖于 iNKT 细胞衍生的白细胞介素 21(IL-21)。然而,iNKT 细胞的同源性帮助并没有产生增强的体液记忆反应。因此,脂质特异性 B 细胞的同源性 iNKT 细胞帮助诱导了一种独特的特征,是经典 T 细胞依赖性和 T 细胞非依赖性 2 型 B 细胞反应的混合体。