The Effect ofBabesia divergensInfection on the Spleen of Mongolian Gerbils

Abstract

Babesiosis is caused by intraerythrocytic protozoan parasites transmitted by ticks and affects a wide range of domestic and wild animals and occasionally humans. The current study aimed to investigate the effect of B. divergens infected erythrocytes on spleen histopathology, cell cycle alteration, and the presence of oxidative stress. Mongolian gerbils were challenged with 5 × 106 Babesia divergens infected erythrocytes. Parasitemia reached approximately 77% at day 5 postinfection. Infection also induced injury of the spleen. This was evidenced with (i) increases in cellular damage of the spleen, (ii) decrease in antioxidant capacity as indicated by decreased glutathione, catalase, and superoxide dismutase levels, (iii) increased production of malondialdehyde and nitric oxide derived products (nitrite/nitrate), and (iv) increased lactic acid dehydrogenase activity and protein carbonyl content in the spleen. Infection interfered with normal cell cycle of the spleen cells at G0/G1, S, and G2/M phases. On the basis of the above results it can be hypothesized that B. divergens infected erythrocytes could alter the spleen histopathology and cause cell cycle alteration and induce oxidative stress in splenic tissue.

The pathology of the spleen in lethal canine babesiosis caused by Babesia rossi

“…The intermingling of these zones was not only observed in the spleens of Babesia divergens ‐infected Mongolian gerbils but also in the spleens of Babesia microti ‐infected mice and Plasmodium falciparum ‐infected humans . To the authors’ knowledge, this is the first evidence to support a similar observation in the spleen of Babesia rossi ‐infected dogs. Babesia divergen s in Mongolian gerbils induced a lethal outcome; all of the animals displayed signs of illness on day 5 and were anaesthetized and killed to allow for splenic examination .…”

“…Increased macrophage densities in the RP were also demonstrated in Plasmodium falciparum ‐infected humans . In B. divergens ‐infected Mongolian gerbils, flow cytometry attributed the observed splenomegaly to increased macrophage densities …”

“…Babesia divergen s in Mongolian gerbils induced a lethal outcome; all of the animals displayed signs of illness on day 5 and were anaesthetized and killed to allow for splenic examination . Microscopic examination revealed the loss of distinction between the WP and the RP . Similar to a study in humans with fatal natural P. falciparum infection, the dogs in the current study were only examined once they had died after severe and advanced disease .…”

“…Malaria has been extensively studied and although the information regarding its effect on the spleen is limited compared with other organs; there is nevertheless a body of published work describing splenic pathology. There is also some literature describing the splenic pathology associated with equine babesiosis, bovine babesiosis and murine babesia . There is nothing published about this aspect of the pathology caused by any babesia species infecting the dog.…”

“…There is also some literature describing the splenic pathology associated with equine babesiosis, bovine babesiosis and murine babesia. [14][15][16][17] There is nothing published about this aspect of the pathology caused by any babesia species infecting the dog. Maegraith et al (1957) noted prominent splenomegaly in a dog with babesiosis with limited information on the actual splenic histomorphology.…”