Proportions of CD4+ memory T cells are altered in individuals chronically infected with Schistosoma haematobium

• DOI: 10.1038/srep00472
• Publication Date: 2012-06-26T12:57:24Z
• Authors: Norman Nausch; Claire D. Bourke; Laura J. Appleby; Nadine Rujeni; Olivier Lantz; François Trottein; Nicholas Midzi; Takafira Mduluza; Francisca Mutapi
• Keywords: Adult; CD4-Positive T-Lymphocytes; Male; 0301 basic medicine; Adolescent; Antibodies, Helminth; Diseases; helminth acquired immunity; Article; 03 medical and health sciences; 0302 clinical medicine; adaptive immune system; /dk/atira/pure/subjectarea/asjc/1000; Animals; Humans; General; Child; Aged; Aged, 80 and over; Analysis of Variance; CD4+ memory T cell; Age Factors; Immunoglobulin E; Middle Aged; Cellular immunity; CD4 Lymphocyte Count; 3. Good health; Immunoglobulin G; Cytokines; Leukocyte Common Antigens; Parasitology; Female; Immunologic Memory

Characterisation of protective helminth acquired immunity in humans or experimental models has focused on effector responses with little work conducted on memory responses. Here we show for the first time, that human helminth infection is associated with altered proportions of the CD4+ memory T cells, with an associated alteration of T(H)1 responses. The reduced CD4+ memory T cell proportions are associated with a significantly lower ratio of schistosome-specific IgE/IgG4 (marker for resistance to infection/re-infection) in uninfected older people. Helminth infection does not affect the CD8+ memory T cell pool. Furthermore, we show for the first time in a helminth infection that the CD4+ memory T cell proportions decline following curative anti-helminthic treatment despite increased CD4+ memory cell replication. Reduced accumulation of the CD4+ memory T cells in schistosome-infected people has implications for the development of natural or vaccine induced schistosome-specific protective immunity as well as for unrelated pathogens.