Ja. Lenzi et al., EFFECTS OF SCHISTOSOMAL MANSONI INFECTION ON CALOMYS CALLOSUS COELOM-ASSOCIATED LYMPHOMYELOID TISSUE (MILKY SPOTS), Memorias do Instituto Oswaldo Cruz, 93, 1998, pp. 13-23
Calomys callosus Rengger, 1830 (Rodentia: Cricetidae) is a mouse-like
South American wild rodent, which is permissive to Schistosoma mansoni
infection. In this paper we studied the effect of schistosomal infect
ion in C. callosus mesenteric and omental milky spots (MS), subsidiary
foci of coelom-associated lymphomyeloid tissue (CALT), during the acu
te, transitional (acute to chronic), and chronic phases of the infecti
on. MS were morphologically analyzed by histological methods, using br
igthfield and confocal laser scanning microscopies. The MS of infected
animals were mainly of lymphomyelocytic (42 to 90 days) and lymphopla
smacytic (160 days of infection) types and showed frequent presence of
lymphoid follicles with germinal centers, plasmacytogenesis and plasm
acytosis, mastocytosis, megakaryopoiesis, erythropoiesis and less pron
ounced eosinopoiesis. These results indicate that MS are a pl preferen
tial site of germinal-center-dependent and independent plasmacytogenes
is, and a bone marrow-like organ, committed with various cellular line
ages. The consequence of C. callosus MS reactivity for schistosomal in
fection is still unknown and is under investigation.