Corbeil L B, Blau K, Prieur D J, Ward A C
J Clin Microbiol. 1985 Aug;22(2):192-8. doi: 10.1128/jcm.22.2.192-198.1985.
The serum susceptibility of 64 isolates of Haemophilus somnus from cattle was determined in a bactericidal assay with undiluted fresh or inactivated bovine serum with serial dilutions of bacterial suspension in RPMI 1640 medium. A total of 27 strains isolated from cattle with clinical disease (4 with thromboembolic meningoencephalitis, 13 with pneumonia, and 10 with reproductive failure) were compared with 35 strains from asymptomatic carriers (11 from the vagina and 24 from the prepuce). Essentially, all clinical isolates were serum resistant, whereas approximately 25% of preputial isolates were serum susceptible, as judged after 1 h of incubation in serum; a majority of vaginal isolates showed delayed serum susceptibility. Lysozyme played no role in serum killing, and the alternative complement pathway played only a minor role. Iron saturation, however, appeared to impart greater serum resistance to serum-susceptible strains from the vagina and prepuce. Perhaps the serum-susceptible strains from carriers would be useful vaccine candidates, but resistant strains from carriers may be pathogenic.
采用杀菌试验，以未稀释的新鲜或灭活牛血清，在RPMI 1640培养基中对细菌悬液进行系列稀释，测定了64株来自牛的睡眠嗜血杆菌的血清敏感性。将从患有临床疾病的牛身上分离出的27株菌株（4株患有血栓栓塞性脑膜脑炎，13株患有肺炎，10株患有生殖衰竭）与35株来自无症状携带者的菌株（11株来自阴道，24株来自包皮）进行了比较。基本上，所有临床分离株均对血清耐药，而在血清中孵育1小时后判断，约25%的包皮分离株对血清敏感；大多数阴道分离株表现出延迟的血清敏感性。溶菌酶在血清杀菌中不起作用，替代补体途径仅起次要作用。然而，铁饱和度似乎赋予来自阴道和包皮的血清敏感菌株更大的血清耐药性。也许来自携带者的血清敏感菌株将是有用的疫苗候选物，但来自携带者的耐药菌株可能具有致病性。
