Memory T-Cell Responses to Vibrio cholerae O1 Infection

• Published in: Infection and Immunity 2009-11, Vol.77 (11), p.5090-5096
• Main Authors: Weil, Ana A, Arifuzzaman, Mohammad, Bhuiyan, Taufiqur R, LaRocque, Regina C, Harris, Aaron M, Kendall, Emily A, Hossain, Azim, Tarique, Abdullah A, Sheikh, Alaullah, Chowdhury, Fahima, Khan, Ashraful I, Murshed, Farhan, Parker, Kenneth C, Banerjee, Kalyan K, Ryan, Edward T, Harris, Jason B, Qadri, Firdausi, Calderwood, Stephen B
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Antibodies, Bacterial - blood; Antibodies, Bacterial - immunology; Antigens, Bacterial - immunology; B-Lymphocytes - immunology; Bacteriology; Biological and medical sciences; Cholera - blood; Cholera - immunology; Enzyme-Linked Immunosorbent Assay; Female; Flow Cytometry; Fundamental and applied biological sciences. Psychology; Humans; Immunity, Cellular - immunology; Immunologic Memory - immunology; Male; Microbial Immunity and Vaccines; Microbiology; Middle Aged; Miscellaneous; T-Lymphocyte Subsets - immunology; Vibrio cholerae; Vibrio cholerae O1 - immunology; Young Adult
• ISSN: 0019-9567; 1098-5522
• DOI: 10.1128/IAI.00793-09

Vibrio cholerae O1 can cause diarrheal disease that may be life-threatening without treatment. Natural infection results in long-lasting protective immunity, but the role of T cells in this immune response has not been well characterized. In contrast, robust B-cell responses to V. cholerae infection have been observed. In particular, memory B-cell responses to T-cell-dependent antigens persist for at least 1 year, whereas responses to lipopolysaccharide, a T-cell-independent antigen, wane more rapidly after infection. We hypothesize that protective immunity is mediated by anamnestic responses of memory B cells in the gut-associated lymphoid tissue, and T-cell responses may be required to generate and maintain durable memory B-cell responses. In this study, we examined B- and T-cell responses in patients with severe V. cholerae infection. Using the flow cytometric assay of the specific cell-mediated immune response in activated whole blood, we measured antigen-specific T-cell responses using V. cholerae antigens, including the toxin-coregulated pilus (TcpA), a V. cholerae membrane preparation, and the V. cholerae cytolysin/hemolysin (VCC) protein. Our results show that memory T-cell responses develop by day 7 after infection, a time prior to and concurrent with the development of B-cell responses. This suggests that T-cell responses to V. cholerae antigens may be important for the generation and stability of memory B-cell responses. The T-cell proliferative response to VCC was of a higher magnitude than responses observed to other V. cholerae antigens.