High levels of circulating IL-10 in human malaria.
IL-10 is a monocyte/lymphocyte derived cytokine which has been shown to inhibit certain cellular immune responses such as delayed hypersensitivity. In particular, the production of tumour necrosis factor (TNF), IL-1 and IL-6, which are involved in malaria pathology, are strongly inhibited by IL-10. Accordingly, we examined whether IL-10 could be involved in a human acute parasitic infection such as Plasmodium falciparum malaria. Human IL-10 levels in plasma were determined by two-site ELISA method, taking care to avoid non-specific reactions due to autoantibodies. Fourteen cerebral, 11 severe, and 20 mild malaria cases had mean IL-10 levels of 2812, 2882 and 913 pg/ml, respectively, while 98% of healthy individuals had undetectable (less than 100 pg/ml) circulating IL-10. Thirteen of the 25 cerebral/severe cases had > 2000 pg/ml. In 11 hospitalized patients, circulating IL-10 levels were found to return to virtually normal levels 7 days after antimalarial chemotherapy when biological and clinical malaria features had disappeared (mean levels fell from 3880 to 333 pg/ml). Further studies are required to determine whether these elevated levels of IL-10 play a beneficial role by reducing the parasite-induced inflammatory response, or a detrimental one by decreasing the cellular immune responses.
Peyron
F
F
Service de Parasitologie, Hôpital de La Croix Rousse, France.
Burdin
N
N
Ringwald
P
P
Vuillez
J P
JP
Rousset
F
F
Banchereau
J
J
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D006801:Humans; D016753:Interleukin-10 / Q000097:blood*; D016778:Malaria, Falciparum / Q000097:blood* / Q000276:immunology; D008875:Middle Aged; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10