Lymphoproliferative and Cytokine Responses to Cryptosporidium parvum in Patients Coinfected with C. parvum and Human Immunodeficiency Virus

We compared the lymphoproliferative and cytokine responses toCryptosporidium parvum in human immunodeficiency virus (HIV)-seropositive and -seronegative patients. The lymphoproliferative and cytokine responses (interleukin-2 [IL-2], IL-4, IL-5, IL-10, gamma interferon, and tumor necrosis factor alpha) were assessed for 11 HIV-seropositive,Cryptosporidium -positive (group I) patients; 20 HIV-seropositive,Cryptosporidium -negative (group II) patients; 10 HIV-seronegative,Cryptosporidium -positive (group III) patients, including four post-renal transplant (group IIIa) and 6 presumably immunocompetent (group IIIb) patients; and 20 HIV-seronegative,Cryptosporidium -negative healthy individuals (group IV). No significant difference was observed in the number of patients showing positive lymphoproliferative responses in group I compared to group III (post-renal transplant [group IIIa] or immunocompetent [group IIIb]) patients, while a comparison of the median stimulation indices shows that responses were significantly lower inCryptosporidium -infected, immunosuppressed (group I and IIIa) patients than in immunocompetent (group IIIb) patients. The number of patients showing positive responses and median stimulation indices was significantly higher forCryptosporidium -infected (HIV-seropositive and -seronegative) individuals than for uninfected individuals, suggesting thatCryptosporidium induces significant in vitro lymphoproliferative responses in infected individuals. Cytokine levels, except for that of IL-5, were significantly higher inCryptosporidium -infected (groups I and III) individuals than in uninfected (groups II and IV) individuals. There was no significant difference between the group I and III patients and betweenCryptosporidium -infected immunosuppressed (group I or IIIa) and immunocompetent (group IIIb) patients.