The Effect of Mycobacterium bovis (Bacillus Calmette-Guérin) on Macrophage Random Migration, Chemotaxis, and Pinocytosis

Macrophage random migration, chemotactic responsiveness, and pinocytosis were studied in the guinea pig after Bacillus Calmette-Guérin (BCG) administration. Oil-induced peritoneal exudate cells were evaluated for random migration and chemotaxis in modified Boyden chambers. Pinocytosis was measured by the in vitro uptake of colloidal¹⁹⁸Au. There was a parallel increase in random migration and chemotaxis after an i.p. dose of 1.0 x 10⁷ colony-forming units of BCG. This was seen as early as Day 4, sustained through Day 21, and absent by Day 44. A number of different strains and preparations of BCG vaccine exerted a similar augmentation of macrophage mobility. In parallel assays, aliquots of macrophages from BCG-treated animals showed increased pinocytosis, first noted at Day 14, peaking at Day 28, and no longer measurable at Day 44. These alterations in macrophage function following BCG administration may in part contribute to the antitumor effect of BCG adjuvant therapy.