Detection of specific antibody responses to vaccination in variable flying foxes (Pteropus hypomelanus)

Abstract

Megachiropteran bats are biologically important both as endangered species and reservoirs for emerging human pathogens. Reliable detection of antibodies to specific pathogens in bats is thus epidemiologically critical. Eight variable flying foxes (Pteropus hypomelanus) were immunized with 2,4-dinitrophenylated bovine serum albumin (DNP-BSA). Each bat received monthly inoculations for 2 months. Affinity-purified IgG was used for production of polyclonal and monoclonal anti-variable flying fox IgG antibodies. ELISA and western blot analysis were used to monitor immune responses and for assessment of polyclonal and monoclonal antibody species cross-reactivity. Protein G, polyclonal antibodies, and monoclonal antibodies detected specific anti-DNP antibody responses in immunized variable flying foxes, with protein G being the most sensitive, followed by monoclonal antibodies and then polyclonal antibodies. While the polyclonal antibody was found to cross-react well against IgG of all bat species tested, some non-specific background was observed. The monoclonal antibody was found to cross-react well against IgG of six other species in the genus Pteropus and to cross-react less strongly against IgG from Eidolon helvum or Phyllostomus hastatus. Protein G distinguished best between vaccinated and unvaccinated bats, and these results validate the use of protein G for detection of bat IgG. Monoclonal antibodies developed in this study recognized immunoglobulins from other members of the genus Pteropus well, and may be useful in applications where specific detection of Pteropus IgG is needed.

Identification of secreted and membrane-bound bat immunoglobulin using a Microchiropteran-specific mouse monoclonal antibody

“…Since the immunogen used to raise the commercial antisera contained E. fuscus IgG, among 11 different bat species, it is not clear whether the binding is due to cross-reactive Abs or due to a mixture of megabat-and microbat-specific Abs in the antisera. It should be noted that Wellehan et al have produced a mAb reactive with megabat IgG by immunization of mice with Pteropus hypomelanus IgG (Wellehan et al, 2009). By western blot analyses, that mAb bound to a number of different Pteropus species and had some cross-reactivity with the one microbat tested (Phyllostomus hastatus).…”

Antiviral Immune Responses of Bats: A Review

“…Early studies of antibody responses in bats were consistent with differences in both the kinetics and magnitude of antibody responses compared with other mammals. Several studies have used model antigens such as sheep red blood cells (SRBCs), φX174 bacteriphage and 2,4‐dinitrophenylated bovine serum albumin (DNP‐BSA) to compare the nature of the antibody response of bats with that of conventional laboratory animals (Hatten et al., 1968, 1970; Chakraborty and Chakravarty, 1984; Wellehan et al., 2009). Hatten et al.…”

Immunoglobulin heavy chain diversity in Pteropid bats: evidence for a diverse and highly specific antigen binding repertoire

“…How bats remain asymptomatic is not known, and few studies have examined the immune response of any bat species. Evidence that antibody responses in bats are both qualitatively and quantitatively lower than other mammals has been reported by a number of investigators (Hatten et al 1968;Wellehan et al 2009;Chakraborty and Chakravarty 1984). In addition, experimental virus infections have demonstrated the simultaneous presence of virus and antibody in bat blood.…”