Effect of modulation of polymorphonuclear leukocyte migration with anti-CD18 antibody on pathogenesis of experimental otitis media in guinea pigs

Guinea pigs were treated with anti-CD18 antibody (M8), and subsequently middle ears (ME) were infected with nontypeable Haemophilus influenzae. Forty-eight hours after infection, the ME washes of these animals had significantly lower polymorphonuclear leukocyte numbers but higher bacterial counts compared with washes of animals treated with control antibody (M11) or saline. The edema and epithelial damage of ME tissues correlated directly with polymorphonuclear leukocyte numbers and not bacterial counts.