Activated CD8+ T cells contribute to clearance of gastric Cryptosporidium muris infections

Abstract

The role of CD4+ and CD8+ T lymphocytes in the development of a protective immune response against Cryptosporidium muris infection was studied by the reconstitution of severe combined immunodeficient (SCID) mice with well-defined populations of either naive or immune CD8+ or CD4+ T lymphocytes. Adoptive transfer of both naive and immune CD4+ T lymphocyte subpopulations protects SCID mice against cryptosporidiosis. Moreover, a significant biological impact of activated CD8+ T cells against gastric cryptosporidiosis was observed. The significant difference in the course and intensity of the infection in reconstituted SCID mice was found to be dependent on the protective function of both the CD4+ and CD8+ T-cell populations transferred. While SCID mice reconstituted with either immune or naive CD4+ or immune CD8+ T-cell subpopulations resolved the infection within 29, 37 and 51 days post-infection, respectively, those reconstituted with naive CD8+ T cells suffered from chronic infection similar to control SCID mice. Reconstitution with CD4+ T cells resulted in suppression of oocyst excretion and shortening of patent period in comparison with SCID mice reconstituted with CD8+ T cells. Thus, although CD4+ T cells are considered important in protective immunity, our results are the first to demonstrate the involvement of activated CD8+ T lymphocytes in the protection of mice against gastric cryptosporidiosis.

Cryptosporidium proliferans n. sp. (Apicomplexa: Cryptosporidiidae): Molecular and Biological Evidence of Cryptic Species within Gastric Cryptosporidium of Mammals

“…The prepatent period for C . proliferans infection in SCID mice, which lack T- and B-cell immunity, ranged from 12–18 DPI with a mean of 14 DPI [ 20 ]. This is similar to the prepatent period for C .…”

Cryptosporidium Priming Is More Effective than Vaccine for Protection against Cryptosporidiosis in a Murine Protein Malnutrition Model

“…Sensitized CD8 + T-cells have a direct role in clearing Cryptosporidium from human epithelial cells [ 51 ] as well as in experimental models of C . muris infection [ 52 , 53 ] and have been shown to accumulate after infection in neonatal mice [ 54 , 55 ]. Preceding the influx CD3 + CD8 + T-cells in this model was an increase in Th1-type chemoattractants CXCL9, CXCL10, CCL3 and CCL5 at peak primary infection.…”

Life cycle ofCryptosporidium murisin two rodents with different responses to parasitization

“…Cryptosporidium muris strain TS03 originating from an East African mole rat (Tachyoryctes splendens) previously characterized by Kváč et al (2008Kváč et al ( , 2011 was used for all experiments in this study. Over 10 years the C. muris TS03 has been passaged through susceptible laboratory hosts, M. coucha and SCID mice, in the Institute of Parasitology Biology Centre, ASCR, v.v.i.…”