Cellular regulation of lung granuloma formation and delayed- type hypersensitivity induced with BCG cell walls. Further evidence of involvement of cellular immunity in lung granuloma formation.

We have previously showed several evidences in which cellular immunity is involved in lung granuloma formation induced with oil-associated BCG cell wall (CW) vaccine. In the present study, we examined in mice the effects of thymectomy, splenectomy and the administration of cyclophosphamide on lung granuloma formation as well as BCG CW-induced footpad reactions to PPD, a prototype of delayed-type hypersensitivity (DTH). The results presented herein provide further evidence that cellular immunoregulatory mechanisms control the development of lung granuloma and DTH, and that lung granuloma formation is thymus- and spleen-dependent.