Antigen-specific memory and naïve CD4+ T cells following secondary Chlamydia trachomatis infection

• DOI: 10.1371/journal.pone.0240670
• Publication Date: 2020-10-22T17:47:38Z
• Authors: Jennifer D. Helble; Alexander O. Mann; Michael N. Starnbach
• Keywords: CD4-Positive T-Lymphocytes; 0301 basic medicine; 0303 health sciences; Coinfection; Science; Q; R; Chlamydia trachomatis; Mice, Transgenic; Chlamydia Infections; 3. Good health; Mice, Inbred C57BL; Mice; 03 medical and health sciences; T-Lymphocyte Subsets; Medicine; Animals; Female; Research Article

Memory antigen-specific CD4+ T cells against Chlamydia trachomatis are necessary for protection against secondary genital tract infection. While it is known that naïve antigen-specific CD4+ T cells can traffic to the genital tract in an antigen-specific manner, these T cells are not protective during primary infection. Here, we sought to compare the differences between memory and naïve antigen-specific CD4+ T cells in the same mouse following secondary infection using transgenic CD4+ T cells (NR1 T cells). Using RNA sequencing, we found that there were subtle but distinct differences between these two T cell populations. Naïve NR1 T cells significantly upregulated cell cycle genes and were more proliferative than memory NR1 T cells in the draining lymph node. In contrast, memory NR1 T cells were more activated than naïve NR1 T cells and were enriched in the genital tract. Together, our data provide insight into the differences between memory and naïve antigen-specific CD4+ T cells during C. trachomatis infection.