[Immunocompetent cells in periapical granuloma III--quantitative relations of B-lymphocyte sub-population].

Our previous studies established that T lymphocytes predominated in diffuse mononuclear infiltrates, whereas B cells were found more frequently in focal infiltrates. In the present study we analysed B cell subpopulation ratios in different types of periapical granuloma mononuclear infiltrates. We used fluorochrome conjugated polyclonal antibodies, specific for human immunoglobulin G, A and M. Quantitative studies showed the presence of B cells with all immunoglobulin classes. The results were as follows: a) the quantitative analysis of cells with different classes of immunoglobulins in diffuse mononuclear infiltrates showed the predominance of IgG (60.65%) in comparison to IgA (24.76%) and IgM (14.59%) positive cells. b) in focal mononuclear infiltrates the prevalence of IgG positive cells was more pronounced (77.15%) comparing to IgA (14.06%) and IgM (8.79%) positive cells (p less than 0.001). Differences in the number of IgA and IgM positive cells did not reach the level of statistical significance. c) the finding of substantial number of B cells, especially of IgG positive cells, suggested that focal infiltrate could be the consequence of exarcerbation of granuloma process caused by delayed action of the agent.