1. T antigens of group A hemolytic streptococci have been obtained in soluble form by digestion of the bacterial cells with pepsin or trypsin. Large quantities of this antigen were readily extracted from type 1 strains, whereas only small amounts could be obtained from strains of other types. 2. The T antigen, prepared in this way from a type 1 strain, was partially purified by chemical precipi...

Currently, there are three Hib conjugate vaccines licensed in Canada for use in infants 2 months of age and older. The Bureau of Biologics recently approved two new vaccine products that allow single-needle administration of (a) polyribose ribitol phosphate-tetanus toxoid (PRP-T) with diphtheria toxoid-pertussis vaccine-tetanus toxoid-inactivated poliovirus vaccine (DPT-IPV), and (b) oligosacch...

Inactivated bovine virus diarrhoea virus, strain 11249nc, inoculated subcutaneously three times with Quil-A into calves protected against intranasal challenge with the same strain. Virus was isolated from nasopharyngeal swabs taken 4 to 8 days post challenge and blood taken 4 to 6 days post challenge from control calves but not from vaccinated calves. A second strain of virus, Ky1203nc, was sel...

An open study was performed to compare the reactogenicity and immunogenicity of an inactivated hepatitis A vaccine administered in two different doses and schedules to 460 healthy volunteers aged 3-18 years. Participants were randomized to two groups to receive either two doses of 720 ELISA Units (EL.U) inactivated hepatitis A per 0.5 ml dose according to a 0, 6-month schedule, or three doses o...

The recommended dosage schedule and type of influenza vaccine are presented in Table 2. Influenza vaccines available in Canada are available as split-virus or inactivated subunit preparations. Two products (Vaxigrip, Fluviral S/F) are split-virus vaccines that are treated with an organic solvent to remove surface glycoproteins, producing a split virus resulting in reduced vaccine reactogenicity...

The protective efficacy of a subunit avian influenza virus H5 vaccine based on recombinant baculovirus expressed H5 haemagglutinin antigen and an inactivated H5N2 avian influenza vaccine combined with a marker antigen (tetanus toxoid) was compared with commercially available inactivated H5N2 avian influenza vaccine in young ducks. Antibody responses, morbidity, mortality, and virus shedding wer...

RE cultures infected with a fixed rabies virus were studied. The virus can propagate itself in these cells for an indefinite period of time without interfering with cell growth. The present study characterizes this truly endosymbiotic relationship. Virus-specific antigen was detected in the cytoplasm of each cell by fluorescein-labeled antirabies serum but only 4 to 5 per cent of the cells rele...

We tested the ability of macaques vaccinated with inactivated whole simian immunodeficiency virus (SIV) to resist challenge with either homologous or heterologous cell-free uncloned SIV administered by the intravenous route. The vaccine virus was derived from a proviral DNA clone and thus was considered genetically homogeneous. Sixteen macaques received either hepatitis B surface antigen (n = 6...

Thirty-eight elderly female subjects (aged 80 +/- 7 years, mean +/- standard deviation) were randomized to immunization with trivalent inactivated influenza virus vaccine containing either purified surface antigen (n = 18) or whole virus (n = 20) components from A/Texas/36/91 (H1N1), A/Beijing/353/89 (H3N2), and B/Panama/45/90 strains. Humoral and cellular immune responses were assessed by meas...

A fluorescence immunoassay for detection of immune complexes bound to solid-phase C1q was developed. The method was standardized by using human aggregated immunoglobulin G (IgG) to simulate immune complexes. A linear relationship existed between the concentrations of the aggregated IgG standards and the resulting fluorescent intensity. The method was found to be reproducible and capable of dete...