EXPRESSION OF OUTER SURFACE-PROTEIN-A AND SURFACE-PROTEIN-C OF BORRELIA-AFZELII IN IXODES-RICINUS TICKS AND IN THE SKIN OF MICE

Several studies have described changes in the expression of proteins, especially of OspA and OspC, of B. burgdorferi sensu stricto during ti ck feeding. In this study, the expression of OspA and OspC of B. afzel ii in unfed and feeding I. ricinus nymphs and in the subsequent adults was followed by means of the immunofluorescence test. Spirochaetes ex pressing OspA and OspC were observed in 70% and 80%, respectively of t he unfed nymphs. In feeding and in fully engorged ticks, spirochaetes expressed OspC, while OspA disappeared 24 hours after the beginning of the blood meal. Spirochaetes expressing OspC in salivary glands were observed in one engorged tick. After molting, in unfed adults spirocha etes again expressed OspA and OspC but did so less frequently (6% and 13%, respectively). The mouse strain (AKR/N or BALB/C) on which ticks had their infectious blood meal influenced OspC expression in the foll owing tick stage. In the skin of AKR/N mice, at the tick feeding site, B. afzelii expressed OspC only, as was shown by immunostaining.