Phagocyte accumulation on the surfaces of PET disks implanted in volunteers with and without the treatment of H1 and H2 histamine receptor antagonists. (A) Myeloperoxidase and non-specific esterase activities were measured to reflect the degree of accumulation of PMN and MØ, respectively. (B) The estimated numbers of adherent PMN, MØ, and total phagocytes (PMN+ MØ) are calculated. Vertical lines denote ± 1 Standard Deviation. Significance vs. control volunteers (without antagonists): * p < 0.05.