Hickman C J, Stover C K, Joseph S W, Oaks E V
Department of Rickettsial Diseases, Walter Reed Army Institute of Research, Washington, D.C. 20307.
Infect Immun. 1993 May;61(5):1674-81. doi: 10.1128/iai.61.5.1674-1681.1993.
A polyclonal T-cell line with TH1 characteristics was used to assess the murine cellular immune response to native and recombinant Rickettsia tsutsugamushi antigens. Proliferation of this T-cell line was observed in response to numerous native antigen fractions, which indicates that the murine T-helper-cell response is directed at multiple scrub typhus antigens with no apparent antigenic immunodominance. Subsequent analysis of recombinant R. tsutsugamushi antigens made it possible to identify a 47-kDa scrub typhus antigen (Sta47) that was stimulatory for the polyclonal T-cell line. Recombinant clones encoding 56-, 58-, and 110-kDa antigens (Sta56, Sta58, and Sta110, respectively) were unable to induce proliferation of this T-cell line. DNA sequence analysis of the cloned rickettsial insert encoding the Sta47 protein revealed the presence of four open reading frames potentially encoding proteins of 47, 30, 18, and 13 kDa. Analysis of sodium dodecyl sulfate-polyacrylamide gel electrophoresis-separated and eluted fractions of lysates from the recombinant HB101(pRTS47B4.3) demonstrated that the fractions containing the 47-kDa protein as well as those containing proteins less than 18 kDa were stimulatory. Selected synthetic amphipathic peptides derived from the Sta47 antigen sequence identified a 20-amino-acid peptide that gave a 10-fold increase in T-cell proliferation over a control malarial peptide of similar length. Recognition of the 47-kDa antigen by a T-cell line with TH1 characteristics implicates this protein as one of potential importance in protection studies and future vaccine development.
使用具有TH1特性的多克隆T细胞系来评估小鼠对天然和重组恙虫病东方体抗原的细胞免疫反应。观察到该T细胞系对多种天然抗原组分有增殖反应，这表明小鼠T辅助细胞反应针对多种恙虫病抗原，且无明显的抗原免疫优势。随后对重组恙虫病东方体抗原的分析使得鉴定出一种对多克隆T细胞系有刺激作用的47 kDa恙虫病抗原（Sta47）成为可能。编码56 kDa、58 kDa和110 kDa抗原（分别为Sta56、Sta58和Sta110）的重组克隆无法诱导该T细胞系增殖。对编码Sta47蛋白的克隆立克次氏体插入片段进行DNA序列分析，发现存在四个开放阅读框，可能编码47 kDa、30 kDa、18 kDa和13 kDa的蛋白质。对重组HB101(pRTS47B4.3)裂解物经十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分离并洗脱的组分分析表明，含有47 kDa蛋白的组分以及含有小于18 kDa蛋白的组分具有刺激作用。从Sta47抗原序列衍生的选定合成两亲性肽鉴定出一种20个氨基酸的肽，其在T细胞增殖方面比类似长度的对照疟疾肽增加了10倍。具有TH1特性的T细胞系对47 kDa抗原的识别表明该蛋白在保护研究和未来疫苗开发中具有潜在重要性。
