Increased eosinophil activity in acute Plasmodium falciparum infection - association with cerebral malaria

TY - JOUR

T1 - Increased eosinophil activity in acute Plasmodium falciparum infection - association with cerebral malaria

AU - Kurtzhals, J A

AU - Reimert, C M

AU - Tette, E

AU - Dunyo, S K

AU - Koram, K A

AU - Akanmori, B D

AU - Nkrumah, F K

AU - Hviid, L

N1 - Keywords: Animals; Biological Markers; Blood Proteins; Child; Cohort Studies; Enzyme-Linked Immunosorbent Assay; Eosinophil Granule Proteins; Eosinophil-Derived Neurotoxin; Eosinophils; Humans; Inflammation Mediators; Interleukin-5; Longitudinal Studies; Malaria, Cerebral; Plasmodium falciparum; Ribonucleases

PY - 1998

Y1 - 1998

N2 - To assess the eosinophil response to Plasmodium falciparum infection a cohort of initially parasite-free Ghanaian children was followed for 3 months. Seven of nine children who acquired an asymptomatic P. falciparum infection showed increase in eosinophil counts, while a decrease was found in seven of nine children with symptomatic malaria, and no change was observed in 14 children who remained parasite-free. In a hospital-based study, paediatric patients with cerebral malaria (CM), severe anaemia (SA), or uncomplicated malaria (UM) had uniformly low eosinophil counts during the acute illness followed by eosinophilia 30 days after cure. Plasma levels of eosinophil cationic protein (ECP) and eosinophil protein X (EPX) were measured as indicators of eosinophil activation. In spite of the low eosinophil counts, ECP levels were increased on day 0 and significantly higher in patients with CM (geometric mean (95% confidence interval) 8.5 ng/ml (6.8-10.7 ng/ml)) than in SA (4.7 ng/ml (3.0-7.5 ng/ml)) and UM patients (4.3 ng/ml (3.6-5.3 ng/ml), P < 0.001). A similar pattern was found for EPX. It thus appears that the low eosinophil counts may be due to tissue sequestration and destruction rather than decreased production. The plasma levels of the granule proteins correlated with levels of tumour necrosis factor and soluble IL-2 receptor, implicating inflammatory responses and T cell activation as causes of the eosinophil activation. By contrast, the eosinophil induction did not appear to be part of a Th2-like response. Eosinophil granule proteins may be important in both control of malaria infection and the pathogenesis of severe malaria.

AB - To assess the eosinophil response to Plasmodium falciparum infection a cohort of initially parasite-free Ghanaian children was followed for 3 months. Seven of nine children who acquired an asymptomatic P. falciparum infection showed increase in eosinophil counts, while a decrease was found in seven of nine children with symptomatic malaria, and no change was observed in 14 children who remained parasite-free. In a hospital-based study, paediatric patients with cerebral malaria (CM), severe anaemia (SA), or uncomplicated malaria (UM) had uniformly low eosinophil counts during the acute illness followed by eosinophilia 30 days after cure. Plasma levels of eosinophil cationic protein (ECP) and eosinophil protein X (EPX) were measured as indicators of eosinophil activation. In spite of the low eosinophil counts, ECP levels were increased on day 0 and significantly higher in patients with CM (geometric mean (95% confidence interval) 8.5 ng/ml (6.8-10.7 ng/ml)) than in SA (4.7 ng/ml (3.0-7.5 ng/ml)) and UM patients (4.3 ng/ml (3.6-5.3 ng/ml), P < 0.001). A similar pattern was found for EPX. It thus appears that the low eosinophil counts may be due to tissue sequestration and destruction rather than decreased production. The plasma levels of the granule proteins correlated with levels of tumour necrosis factor and soluble IL-2 receptor, implicating inflammatory responses and T cell activation as causes of the eosinophil activation. By contrast, the eosinophil induction did not appear to be part of a Th2-like response. Eosinophil granule proteins may be important in both control of malaria infection and the pathogenesis of severe malaria.

U2 - 10.1046/j.1365-2249.1998.00586.x

DO - 10.1046/j.1365-2249.1998.00586.x

M3 - Journal article

C2 - 9649195

SN - 0964-2536

VL - 112

SP - 303

EP - 307

JO - Clinical and Experimental Immunology, Supplement

JF - Clinical and Experimental Immunology, Supplement

IS - 2

ER -