Serum IL-4, IL-12 and TNF-alpha in malaria: a comparative study associating cytokine responses with severity of disease from the Coastal Districts of Odisha

Abstract

We investigated the role of IL-4, IL-12 and TNF-alpha in clinically well-defined groups of Plasmodium falciparum and vivax (Pf & Pv) infected patients belonging to Group I (++), Group II (+++) and Group III (++++). On the basis of hematological parameters, hyperparasitaemia, and evidence of neurological involvement, three different levels of severity were selected attributing a score from Group I (++) to Group III (++++). In each group 16 patients each of P. falciparum and P. vivax malaria were studied. As a control group for cytokine determination 30 healthy volunteers were included in the study. Serum samples were analyzed for IL-12, IL-4 and TNF-alpha using (ELISA) obtained commercially (Ray Biotech). Hb levels of Pf and Pv patients were 8 ± 1.94, 7.6 ± 1.64 g/dl and 3.6 ± 1.23 and 10.1 ± 1.21, 9.4 ± 1.43 and 7.1 ± 0.98 g/dl. Serum iron levels of Pf and Pv patients were 85.86 ± 0.86, 81.10 ± 0.70 and 70.1 ± 0.73 and 99.47 ± 0.85, 96.67 ± 1.13 and 91.7 ± 2.65 mg/dl. TNF-alpha levels of Pf and Pv patients were 155 ± 23.66, 307.5 ± 111.87 and 955 ± 261.32 and 72 ± 9.93, 140.88 ± 23.11 and 469.37 ± 416.99 pg/ml. IL-12 levels of Pf and Pv patients were 117.5 ± 8.16, 160.63 ± 20.81 and 293.13 ± 94.64 and 75.7 ± 9.25, 112.9 ± 12.05 and 200 ± 53.78 pg/ml. IL-4 levels of Pf and Pv patients were 3.7 ± 0.11, 3.2 ± 0.13 and 2.3 ± 0.63 and 5.33 ± 1.08, 4.8 ± 0.16 and 3.9 ± 0.48 pg/ml. In the control group the values of TNF-alpha, IL-12 and IL-4 were 42.9 ± 13.5, 49.8 ± 11.59 and 6.06 ± 1.32 pg/ml respectively. Cytokines and poor oxygen delivery should not be viewed as alternative theories of malarial disease pathophysiology instead poor oxygen delivery is one of the consequences of excessive release of inflammatory cytokines which is further augmented by the present work.

Keywords: Clinical severity; Cytokines; IL-12; IL-4; Malaria; TNF-alpha.