Dendritic cell TLR4 induces Th1-type immune response against Cryptosporidium parvum infection

@#The objective of this study was to investigate the mechanism of Toll-like receptor (TLR4)- mediated dendritic cell (DC) immune against Cryptosporidium parvum infection. C. parvum sporozoites were labeled with 5,6-carboxyfluorescein diacetate succinimidyl ester. Murine bone marrow-derived DCs were isolated, and divided into TLR4 antibody blocking (TAB; infected with 2 × 105 labeled sporozoites and 0.5 μg TLR4 blocking antibody), TLR4 antibody unblocking (TAU; infected with 2 × 105 labeled sporozoites), and blank control (BC; with 1.5 mL Roswell Park Memorial Institute 1640 medium) groups. The adhesion of Cryptosporidium sporozoites to DCs and CD11c+ levels were examined by fluorescence microscopy and flow cytometry. Male KM mice were orally injected with C. parvum. The proliferation of T lymphocytes in spleen, expression of cytokines in peripheral blood, and TLR4 distribution features in different organs were further determined by immunohistochemistry. A significantly higher expression of CD11c+ and higher C. parvum sporozoite adhesion were found in the TAU group compared with other groups. The expression of CD4+CD8- /CD8+CD4- in the spleen were obviously differences between the TAB and TAU groups. The expression of TLR4, interleukin IL-4, IL-12, IL-18 and IFN-γ improved in the TAU group compared with TAB group. Higher expression of TLR4 was detected in the lymph nodes of mice in the TAU group, with pathological changes in the small intestine. Hence, TLR4 could mediate DCs to recognize C. parvum, inducing Th1 immune reaction to control C. parvum infection.

Essai de mise au point d'un colorant cellulaire : le NEO-FME

Les auteurs proposent un colorant cytologique polychrome a base de fichsine; bleu de methylene et d'eosine. De realisation rapide selon un protocole simple; cette coloration permet une bonne differenciation des structures nucleaires et cytoplasmiques. Le NEO-FME est indique pour la recherche et l'identification des plasmodiums sp dans le sang et pour la realisation de la formule leucocytaire. La rapidite de sa mise en oeuvre (3 a 4 mn) permet un gain de temps inestimable entre examen du patient et decision therapeutique; d'ou son importance dans l'amelioration du pronostic vital

Potency control of live, attenuated vaccines against measles used in children vaccinations in the State of Sao Paulo, Brazil (1976-1980).

Pela inoculacao de diluicoes seriadas da vacina viva, atenuada, contra o sarampo,em culturas de celulas Vero, foram titulados para controle de potencia, 161 lotes de vacinas importadas da Inglaterra, Franca e Belgica, destinadas a vacinacao da populacao infantil do Estado de Sao Paulo. Nas condicoes do teste, 20,0, 11,5 e 25,0% dos lotes de vacina testadas, importadas da Inglaterra, Franca e Belgica respectivamente, nao apresentaram o titulo minimo exigido; dentre os 72 lotes importados da Franca e liofilizados no Brasil, nao ocorreram impugnacoes devidas a insuficiencia de titulo