Immunization of virgin cows with surface antigen TF1.17 of Tritrichomonas foetus

Abstract

Protection by surface antigen TF1.17 of Tritrichomonas foetus was investigated because it reacted with a monoclonal antibody which immobilized and mediated complement killing of the organism and prevented adherence to vaginal epithelial cells. This monoclonal antibody was used to demonstrate conservation of the antigen in most strains and to immunoaffinity purify the 50- to 70-kDa glycoprotein antigen. In preparation for immunization studies, the appropriate challenge dose of parasites was determined by intravaginal inoculation of 23 virgin cows (heifers) with 10(2), 10(4), or 10(6) live organisms at the time of estrus. More animals became infected and vaginal infection was maintained at a higher rate (P < 0.005) over 10 weeks for the group that received 10(6) organisms than in the other two groups. Therefore, this dose was used for challenge of immunized animals. Animals immunized with immunoaffinity-purified TF1.17 antigen in incomplete Freund's adjuvant or incomplete Freund's adjuvant plus dextran sulfate cleared the infection more quickly than adjuvant controls (P < 0.005). Isotype-specific enzyme-linked immunosorbent assay with T. foetus antigen showed that serum immunoglobulin G1 (IgG1) and IgG2 antibody responses as well as cervicovaginal mucus IgG1 and IgA antibodies peaked at about the time of clearance of infection in vaccinated animals. Controls developed later cervicovaginal mucus IgA antibody responses as would be expected in a primary local immune response to infection. These results indicate that vaccination with this immunoaffinity-purified surface antigen of T. foetus enhances antibody responses as well as clearance of the parasite from the female reproductive tract.

Bovine Trichomoniasis as a Model for Development of Vaccines against Sexually‐transmitted Disease

“…Cows and heifers with no previous T. foetus contact can be infected with as low as 100-200 motile cells in the anterior vagina. 11,13,15 Vaginitis, endometritis and reproductive failure result. 15,16 The fetus is typically lost between 9 and 20 weeks of the 40-week gestation period, 11,17,18 but sometimes third trimester losses occur.…”

“…30 The mAbs also reacted strongly with T. foetus LPG. 29 Therefore, Mab TF1.17 was used to immunoaffinity purify a highly glycosylated surface antigen, referred to as TF1.17 antigen, 13 with similar lipid and monosaccharide composition to T. foetus LPG. 31…”

Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): Trichomonosis

“…In a more recent study from Argentina, several heifers remained infected up to 300 days after breeding (Mancebo et al, 1995). Parsonson et al (1976), Skirrow and BonDurant (1990), BonDurant et al (1993), Anderson et al (1996)…”

Mucosal Veterinary Vaccines

“…This glycosylated surface antigen was later shown to be a lipophosphoglycan (LPG)/protein complex. Systemic immunization with the immunoaffinity-purified LPG-containing surface antigen, followed by intravaginal challenge with T. foetus, resulted in significantly earlier clearance of the parasite from vaccinated animals than from controls (BonDurant et al, 1993;Corbeil et al, 2001). More importantly, clearance of immunized animals most often occurred before 7 weeks of infection.…”

“…Older bulls have deeper epithelial crypts, which may have lower oxygen tension. In order to understand protective acquired immune responses, monoclonal antibodies (mAbs) with putative protective functions were chosen for immunoaffinity purification of a highly glycosylated surface antigen (BonDurant et al, 1993;Corbeil et al, 2001). Analysis of many isolates of T. foetus indicated that two mAbs recognized different epitopes of the same antigen, which was conserved in all isolates tested.…”