DR*W201/P65 Tetramer Visualization of Epitope-Specific CD4 T-Cell during M. tuberculosis Infection and Its Resting Memory Pool after BCG Vaccination

作者：Wei Huiyong^*; Wang Richard; Yuan Zhuqing; Chen Crystal Y; Huang Dan; Halliday Lisa; Zhong Weihua; Zeng Gucheng; Shen Yun; Shen Ling; Wang Yunqi; Chen Zheng W

来源：PLos One, 2009, 4(9): e6905.

DOI：10.1371/journal.pone.0006905

Background: In vivo kinetics and frequencies of epitope-specific CD4 T cells in lymphoid compartments during M. tuberculosis infection and their resting memory pool after BCG vaccination remain unknown.
Methodology/Findings: Macaque DR*W201 tetramer loaded with Ag85B peptide 65 was developed to directly measure epitope-specific CD4 T cells in blood and tissues form macaques after M. tuberculosis infection or BCG vaccination via direct staining and tetramer-enriched approach. The tetramer-based enrichment approach showed that P65 epitope-specific CD4 T cells emerged at mean frequencies of similar to 500 and similar to 4500 per 10(7) PBL at days 28 and 42, respectively, and at day 63 increased further to similar to 22,000/10(7) PBL after M. tuberculosis infection. Direct tetramer staining showed that the tetramer-bound P65-specific T cells constituted about 0.2-0.3% of CD4 T cells in PBL, lymph nodes, spleens, and lungs at day 63 post-infection. 10-fold expansion of these tetramer-bound epitope-specific CD4 T cells was seen after the P65 peptide stimulation of PBL and tissue lymphocytes. The tetramer-based enrichment approach detected BCG-elicited resting memory P65-specific CD4 T cells at a mean frequency of 2,700 per 10(7) PBL.
Significance: Our work represents the first elucidation of in vivo kinetics and frequencies for tetramer-bound epitope-specific CD4 T cells in the blood, lymphoid tissues and lungs over times after M. tuberculosis infection, and BCG immunization.

• 出版日期2009-9-4