A pro-inflammatory effect of foot and mouth disease vírus on immune and non immune guinea pigs

Abstract

The O_1Campos strain of foot and mouth disease virus (FMDV) used as inducing agent in the pleurisy model was able to trigger a pro-inflammatory effect on normal and immune guinea pigs. The proinflammatory activity which was detected at two times of the pleurisy (24 and 48 hours) on normal guinea pigs was characterized only by mononuclear (MN) cell influx, during the first interval of the reaction and by edematogenic effect, MN and polimorphonuclcar (PMN) leucocyte migration, at the last time of the reaction. The inflammatory reaction profiles recorded on immune guinea pigs (vaccinated with anti-O_1Campos oil adjuvanted vaccine), both after 7 and 30 days post vaccination (pv) have showed, in both interval, lower intensities than that observed in normal guinea pigs, although in the 7 days PV guinea pigs the accumulations of total leucocytes and PMN were similar to that displayed by normal animals, after 48 hours of the reaction. Besides, on thirty days PV guinea pigs the FMDV induced a significant increase in volume of exudate and MN cell infiltration, after 24 hours, and all of the inflammatory parameters values dropped to normal levels, during the second interval of the reaction. It was found a negative association between the increase in serum neutralizing antibody titer, from 7 to 30 days PV and the intensities of pleural inflammatory parameters on the immune guinea pigs. The pleurisy test revealed itself feasible to evaluate the pro-inflammatory activity of FMDV.