Mendiratta S K, Singh N, Bal V, Rath S
National Institute of Immunology, New Delhi, India.
Immunology. 1996 Oct;89(2):238-44. doi: 10.1046/j.1365-2567.1996.d01-739.x.
We have characterized two unusual T-cell hybridomas, 1E3 and 3B8, from H-2k mice immunized with I-Ab-transfected L cells (H-2k), that are stimulated by L cells transfected with I-Ab, I-Ak or I-Eb, but not by non-transfected L cells. These hybridomas could not be stimulated by spleen cells from H-2i3, H-2k, H-2b or H-2d mice. Monoclonal anti-I-A antibodies did not block their responses, suggesting that mouse major histocompatibility complex (MHC) class II molecules may be peptide donors rather than restriction elements for them. The stimulation of these hybridomas by fibroblast targets was not blocked by an anti-H-2kk, Dk-specific monoclonal antibody. Lipopolysaccharide (LPS)-activated splenic and peritoneal exudate cells from H-2k, H-2d, H-2i3, H-2b as well as beta 2-microglobulin-deficient, TAP-1-deficient and I-A alpha-deficient H-2b mice stimulated these hybridomas. LPS could also activate a macrophage cell line, but not a B-cell line, to become stimulatory for 1E3. A rat antiserum against untransfected L cells specifically and significantly blocked the response of 1E3. Thus, 1E3 may recognize a conserved murine MHC class II peptide loaded in a TAP-1-independent fashion on a non-classical, monomorphic, beta 2-microglobulin-independent restriction element.
我们已对来自用I-Ab转染的L细胞（H-2k）免疫的H-2k小鼠的两种异常T细胞杂交瘤1E3和3B8进行了表征，它们受到用I-Ab、I-Ak或I-Eb转染的L细胞刺激，但不受未转染的L细胞刺激。这些杂交瘤不能被来自H-2i3、H-2k、H-2b或H-2d小鼠的脾细胞刺激。单克隆抗I-A抗体不能阻断它们的反应，这表明小鼠主要组织相容性复合体（MHC）II类分子可能是它们的肽供体而非限制元件。成纤维细胞靶标对这些杂交瘤的刺激未被抗H-2kk、Dk特异性单克隆抗体阻断。来自H-2k、H-2d、H-2i3、H-2b以及β2-微球蛋白缺陷、TAP-1缺陷和I-Aα缺陷的H-2b小鼠的脂多糖（LPS）激活的脾细胞和腹腔渗出细胞刺激了这些杂交瘤。LPS也能激活一种巨噬细胞系，但不能激活B细胞系，使其对1E3具有刺激作用。一种针对未转染L细胞的大鼠抗血清特异性且显著地阻断了1E3的反应。因此，1E3可能识别一种以不依赖TAP-1的方式加载在非经典、单态、不依赖β2-微球蛋白的限制元件上的保守小鼠MHC II类肽。
