CELLULAR AND HUMORAL IMMUNE-RESPONSE OF FOALS TO VACCINATION WITH CORYNEBACTERIUM-EQUI

  • 1 January 1979
    • journal article
    • research article
    • Vol. 43  (4) , 356-364
Abstract
Transformation of peripheral blood lymphocytes from pony foals vaccinated and subsequently infected with C. equi was studied. Three foals were vaccinated on 2 occasions using a formalinized C. equi vaccine with Al(OH)3 as an adjuvant. Three non-vaccinated foals served as controls. Foals were challenged intratracheally with 9 .times. 109 C. equi 6 wk after the initial vaccination. Foals survived this infection for 1-2 wk. Significant lymphocyte transformation in response to C. equi antigens was detected in 2 vaccinated foals at the 3rd wk after initial vaccination and in all vaccinated animals at the 5th wk. No statistically significant transformation was seen in non-vaccinated foals before infection. Vaccinated and non-vaccinated foals showed responsive lymphocytes following challenge. Vaccination offered no obvious protection against experimental challenge but this failure was probably due to an excessive infective dose of organisms. Low levels of humoral antibodies were detected in some challenged foals. The pathological changes in the lungs of infected animals were comparable with, but more fulminating than, changes observed in the natural disease.