[Phagocytic activity in PMN leukocytes and macrophages of athymic nu/nu mice].

The athymic nu/nu mice represent a natural model for studying defense mechanisms. This study had the object of evaluating the phagocytic activity of polymorphonuclear leucocytes (PMN) and peritoneal macrophages (PM) in congenitally athymic homozygotic nu/nu mice. The results showed that the chemotaxis, random mobility, ingestion of latex particles and reduction of nitroblue tetrazolium were all normal.

Pulmonary toxicity of oxygen.

Prolonged exposure to hyperoxia in order to compensate for inefficient ventilation can lead to progressive pulmonary damage and death. Since pulmonary macrophages control bacterial and viral penetration, we studied the effect of hyperoxia on pulmonary alveolar macrophages from newborn and adult rats, kept in air or in a 95% normobaric oxygen atmosphere. The viability of pulmonary alveolar macrophages in bronchoalveolar lavages of newborn rats after 3 d in oxygen was significantly lower than that of newborn rats after 3 days in air.

[Evaluation of immune response in experimental sporotrichosis using T and B lymphocyte count].

The effector cells of the immune response are involved in the clinical course of bacterial, viral and mycotic infections. Previous publications have reported that some mycotic infections, including sporotrichosis, can produce a negative modulation of the immune response unfavorable for the host. In this work T and B lymphocytes capable to form direct and indirect rosettes respectively with sheep erythrocytes in gerbils with experimental sporotrichosis, were measured.

[Leukocyte phagocytic activity in gerbils with experimental sporotrichosis treated with potassium iodide].

One effective treatment against sporotrichosis is the oral administration of potassium iodide (KI). It is not known how it works, and also it is not known if this substance has some effect on the microbicidal activity of polymorphonuclear neutrophils (PMN) and macrophages. In this work the phagocytic activity of gerbils treated with KI was studied.