Quantitative and morphological changes in BAL-isolated cells after the administration of TNF-alpha into Morris hepatoma.

The aim of this study was to explore the effect of intratumor TNF-alpha administration upon the composition and adherence degree of cells isolated from the lungs through multiple bronchoalveolar lavages (BAL). Ultrastructural evaluation of BAL-isolated cells was performed in the scanning electron microscope (SEM). The experiment used Buffalo rats. A suspension of 3 x 10(6) cells of Morris hepatoma (5123 series) was injected to the right hind leg of the animals. After fourteen days, TNF-alpha was administered into the tumor in a dose of 1.5 x 10(4) U in 0.5 ml PBS solution. The animals of group I were given 4 doses of TNF-alpha and group II-8 doses of TNF-alpha every 24 hours. Control groups consisted of rats with injected Morris hepatoma which were given PBS solution instead of TNF-alpha (group III A, B) and animals without the hepatoma, given intramuscullary 4 or 8 TNF-alpha, respectively (groups IV A, B). No statistically significant differences were noticed between groups I and II with regard to the number of macrophages and neutrophils isolated from the rat lungs compared with control group IV. However, such differences were observed compared with group III. In group II and IV B, an increase in the adherence of isolated cells was found compared with group III, as well as arise in the number of macrophages with the largest diameters. We found a correlation between the increase in cell adherence and ultrastructural changes (in SEM) suggesting an increased activity of BAL-isolated cells.