Kinetics of mobilization and differentiation of lymphohematopoietic cells during experimental murine schistosomiasis in galectin-3(-/-) mice

Galectin-3 (gal-3), a beta-galactoside-binding animal lectin, plays a role in cell-cell and cell-extracellular matrix interactions. Extracellular gal-3 modulates cell migration and adhesion in several physiological and pathological processes. Gal-3 is highly expressed in activated macrophages. Schistosoma mansoni eggs display a large amount of gal-3 ligands on their surface and elicit a well-characterized, macrophage-dependent, granulomatous, inflammatory reaction. Here, we have investigated the acute and chronic phases of S. mansoni infection in wild-type and gal-3(-/-) mice. in the absence of gal-3, chronic-phase granulomas were smaller in diameter, displaying thinner collagen fibers with a loose orientation. Schistosoma-infected gal-3(-/-) mice had remarkable changes in the monocyte/ macrophage, eosinophil, and B lymphocyte subpopulations as compared with the infected wild- type mice. We observed a reduction of macrophage number, an increase in eosinophil absolute number, and a decrease in B lymphocyte subpopulation (B220(+/high) cells) in the periphery during the evolution of the disease in gal-3(-/-) mice. B lymphopenia was followed by an increase of plasma cell number in bone marrow, spleen, and mesenteric lymph nodes of the infected gal-3(-/-) mice. the plasma IgG and IgE levels also increased in these mice. Gal-3 plays a role in the organization, collagen distribution, and mobilization of inflammatory cells to chronic-phase granulomas, niches for extramedullary myelopoiesis, besides interfering with monocyte-to-macrophage and B cell-to-plasma cell differentiation.Univ Fed Rio de Janeiro, Dept Histol & Embriol, Rio de Janeiro, BrazilUniversidade Federal de São Paulo, Fac Med, Expt Oncol Lab, São Paulo, BrazilCEPID FAPESP, Ctr Cell Based Therapy, São Paulo, BrazilUniv Calif Davis, Sch Med, Dept Dermatol, Sacramento, CA 95817 USAUniversidade Federal de São Paulo, Fac Med, Expt Oncol Lab, São Paulo, BrazilWeb of Scienc