0000000001092665
AUTHOR
Tesfaye Sisay Tessema
Binding and activation of human and mouse complement by Cryptosporidium parvum (Apicomplexa) and susceptibility of C1q- and MBL-deficient mice to infection.
Cryptosporidium parvum is a protozoan parasite (Apicomplexa) that causes gastrointestinal disease in animals and humans. Whereas immunocompetent hosts can limit the infection within 1 or 2 weeks, immunocompromised individuals develop a chronic, life-threatening disease. The importance of the adaptive cellular immune response, with CD4+ T-lymphocytes being the major players, has been clearly demonstrated. Several non-adaptive immune mechanisms have been suggested to contribute to the host defence, such as interferon-gamma (IFN-gamma) from NK cells, certain chemokines, beta-defensins and pro-inflammatory cytokines, but the influence of the complement systems has been less well studied. We ana…
Host immune response to Cryptosporidium parvum infection
Species of the genus Cryptosporidium are protozoan parasites (Apicomplexa) that cause gastroenteritis in animals and humans. Of these Cryptosporidium parvum and Cryptosporidium hominis are the major causative agents of human cryptosporidiosis. Whereas infection is self-limiting in the immunocompetent hosts, immunocompromised individuals develop a chronic, life-threatening disease. As specific therapeutic or preventive interventions are not yet available, better understanding of the immune response to the parasite is required. This minireview briefly summarizes the factors involved in the innate and acquired immune response in this pathogen-host interaction with an emphasis on more recent da…
Adoptive transfer of protective immunity from Cryptosporidium parvum-infected interferon-gamma and interleukin-12-deficient mice to naive recipients.
We investigated the possibility of transfer immunity from Cryptosporidium parvum-infected interferon-gamma (GKO) and interleukin-12p40 (IL-12KO) deficient C57BL/6 mice to naive mice by transfer of intraepithelial lymphocytes (IELs) and CD4(+) T cells from spleen and mesenteric lymph nodes (MLNs). Three days after the transfer recipients were infected with C. parvum. IELs isolated from GKO donor mice after resolution of infection (day 15) but not at the peak of infection (day 8) significantly reduced the parasite load in recipient mice. In IL-12KO mice, IELs and also CD4(+) T cells isolated from the spleen and MLNs of donor mice at the peak of infection (day 5) and after resolution (day 15) …
Dynamics of gut mucosal and systemic Th1/Th2 cytokine responses in interferon-gamma and interleukin-12p40 knock out mice during primary and challenge Cryptosporidium parvum infection.
Cryptosporidium parvum is an intracellular parasite causing enteritis which can become life-threatening in the immunocompromised host. CD4+ T cells and interferon (IFN)-gamma play dominant roles in host immune response to infection. However, effector mechanisms that are responsible for recovery from infection are poorly understood. In the present study we analyzed mice deficient in IFN-gamma or interleukin (IL)-12 in parallel to C57BL/6 wild type mice as models for murine cryptosporidiosis. Our results identified IFN-gamma as the key cytokine in the innate as well as adaptive immunity during primary and also challenge C. parvum infection. Furthermore, both Th1 and Th2 cytokines appear to co…