Senpuku H, Iizima T, Koga T, Nisizawa T
Department of Oral Science, National Institute of Health, Tokyo, Japan.
Oral Microbiol Immunol. 1996 Oct;11(5):343-9. doi: 10.1111/j.1399-302x.1996.tb00192.x.
A 190-kDa surface protein antigen (PAc) of Streptococcus mutans is considered to play an important role in dental caries. To identify antigenic epitopes of the PAc in humans, we immunized severe combined immunodeficient (SCID) mice with recombinant PAc that was transplanted with human peripheral blood mononuclear cells (PBMC). The reactivities of the sera from the immunized hu-PBL-SCID mice to the recombinant PAc and 24 19-mer synthetic peptides covering the alanine-rich repeating region (A-region) presented in the PAc molecule were then examined. The results showed that the immunized mice produced a significant recombinant PAc-specific human antibody, and among 24 19-mer peptides, 6 19-mer peptides showed a strong reaction with the antibodies. In addition, 4 19-mer peptides containing human antigenic epitope in a donor were identified with enzyme-linked immunosorbent assay (ELISA) inhibition assays using the recombinant PAc protein. In this study, the SCID mouse was useful in identifying human antigenic epitopes.
变形链球菌的一种190 kDa表面蛋白抗原（PAc）被认为在龋齿形成中起重要作用。为了鉴定人类体内PAc的抗原表位，我们用移植了人外周血单核细胞（PBMC）的重组PAc免疫重症联合免疫缺陷（SCID）小鼠。然后检测免疫后的人-PBL-SCID小鼠血清对重组PAc以及覆盖PAc分子中富含丙氨酸重复区域（A区）的24种19肽合成肽的反应性。结果显示，免疫小鼠产生了显著的重组PAc特异性人抗体，在24种19肽中，6种19肽与抗体呈现强烈反应。此外，使用重组PAc蛋白通过酶联免疫吸附测定（ELISA）抑制试验鉴定出供体中4种含有人抗原表位的19肽。在本研究中，SCID小鼠有助于鉴定人抗原表位。
