Infection with Plasmodium chabaudi diminishes plasma immune complexes and ameliorates the histopathological alterations in different organs of female BWF1 lupus mice.

OBJECTIVE: To determine the effect of Plasmodium chabaudi infection on the plasma level of circulating immune complexes (CICs), haemoglobin (Hb) content, urine profile, and histological features of female BWF1 mice, the murine model of systemic lupus erythematosus (SLE).

MATERIALS AND METHODS: A total of 30 female BWF1 lupus mice were randomly divided into three groups as follows: group (I) control group (P. chabaudi uninfected); group (II) lupus mice infected with live P. chabaudi; group (III) lupus mice infected with irradiated P. chabaudi. Urine samples were daily collected from the second week-post infection. Mice from the three groups were killed at day 14 post-infection and heparinized blood was collected for further haemoglobin contents and plasma analysis. Paraffin-embedded kidney, liver, lung, heart, brain, ovary and skin tissues were stained with Hematoxylin and Eosin (H&E) and examined under light microscope.

RESULTS: Our results reveal that infection of lupus mice with live P. chabaudi was associated with an increase in urinary Hb and a decrease in plasma Hb and CIC levels. Interestingly, infection of lupus mice with live P. chabaudi ameliorates the histopathological alterations mediated by lupus disease in kidney tissues. Although no parasite sequestration was observed in any of the investigated organs, P. chabaudi pigment deposition was observed in the liver of both live and irradiated P. chabaudi infected groups.

CONCLUSIONS: This study in lupus prone BWF1 mice indicated that gamma-irradiated P. chabaudi infection has the desired lupus ameliorating effect without negative effects of malaria which assist the understanding of different responses to plasmodium sp. infection in human lupus patients.