使用 HtsA（一种链球菌血红素转运蛋白）进行主动和被动免疫可保护小鼠免受皮下 A 组链球菌感染。

Active and passive immunizations with HtsA, a streptococcal heme transporter protein, protect mice from subcutaneous group A Streptococcus infection.

机构信息

Department of Physiology, College of Basic Medical Science, Harbin Medical University, China.

出版信息

J Microbiol Immunol Infect. 2020 Feb;53(1):87-93. doi: 10.1016/j.jmii.2018.03.002. Epub 2018 May 17.

DOI:10.1016/j.jmii.2018.03.002

Abstract

BACKGROUND/PURPOSE: HtsA (Streptococcus heme transporter A) is the lipoprotein component of the streptococcal heme ABC transporter (HtsABC). The aim of this study is to investigate whether the HtsA protein has immunoprotective effect against group A Streptococcus (GAS) infection in mice.

METHODS

The HtsA protein was purified by sequential chromatography on Ni-sepharose, DEAE-sepharose and Phenyl-sepharose, CD-1 mice were actively immunized with ALUM (control) or HtsA/ALUM, and passively immunized with control or anti-HtsA serum. Mice were challenged with GAS after immunization, and the survival rate, skin lesion size and systemic GAS dissemination were determined.

RESULTS

The HtsA gene was cloned, and the recombinant protein HtsA was successfully purified. HtsA has a strong antigenicity, and active immunization with the HtsA protein significantly protected mice against lethal subcutaneous GAS infection, inhibited invasion of the skin by GAS, and reduced GAS systemic dissemination in blood and organs. In addition, passive immunization with anti-HtsA serum also significantly protected mice against subcutaneous GAS infection, and inhibited invasion of the skin by GAS.

CONCLUSION

The results showed that both active and passive immunization with the HtsA protein protected mice against subcutaneous GAS infection, suggesting that HtsA may be a candidate of GAS vaccine to protect against GAS infection.

摘要

背景/目的：HtsA（血红素转运蛋白 A）是链球菌血红素 ABC 转运体（HtsABC）的脂蛋白成分。本研究旨在探讨 HtsA 蛋白是否对 A 组链球菌（GAS）感染具有免疫保护作用。

方法

通过 Ni-琼脂糖、DEAE-琼脂糖和 Phenyl-琼脂糖的顺序色谱法纯化 HtsA 蛋白，用 ALUM（对照）或 HtsA/ALUM 对 CD-1 小鼠进行主动免疫，用对照或抗 HtsA 血清进行被动免疫。免疫后用 GAS 对小鼠进行攻击，测定生存率、皮肤损伤大小和全身 GAS 传播情况。

结果

克隆了 HtsA 基因，成功纯化了重组蛋白 HtsA。HtsA 具有很强的抗原性，用 HtsA 蛋白进行主动免疫可显著保护小鼠免受致死性皮下 GAS 感染，抑制 GAS 对皮肤的侵袭，并减少血液和器官中 GAS 的全身传播。此外，用抗 HtsA 血清进行被动免疫也显著保护小鼠免受皮下 GAS 感染，抑制 GAS 对皮肤的侵袭。