Herzog M, Lafage M, Montaño-Hirose J A, Fritzell C, Scott-Algara D, Lafon M
Unité de la Rage, Hôpital Pasteur, Paris, France.
Virus Res. 1992 Jun;24(1):77-89. doi: 10.1016/0168-1702(92)90032-5.
The importance of the immune response directed to the internal component of the rabies virus, the nucleocapsid (NC), was evaluated in humans after rabies vaccination. T cell activation was measured with a bulk proliferative assay and relative frequencies of circulating NC-specific PBL were calculated with the limiting dilution technique. Vaccinees were classified into two groups: NC responders and NC non-responders. In NC responders, the frequency of NC-specific circulating lymphocytes was up to 6 times higher than the frequency of virus-specific lymphocytes. In non-responders, NC-specific lymphocytes were up to 25 times less common than virus-specific ones. The NC capacity to induce a secondary antibody response was tested in vitro. After a stimulation with complete virus, lymphocytes originating from donors vaccinated with tissue culture vaccine produced a secondary antibody-response composed mainly of glycoprotein-specific neutralizing antibodies, whereas lymphocytes from suckling mouse brain vaccines produced essentially NC-specific antibodies. This result confirmed the serological status of suckling mouse brain vaccinees, who usually developed high titres of NC-specific antibodies. After an in vitro NC stimulation, lymphocytes collected from NC responders produced not only NC-specific antibodies, provided they have NC-specific B cells at the time of blood sampling, but most surprisingly, they also produce glycoprotein-specific neutralizing antibodies. This finding indicates that NC free of glycoprotein is capable, in some individuals, of boosting an heterologous glycoprotein response.
