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Biomedical subjects

J Gruber

Publications and source records attributed to J Gruber.

At least 91 records · Page 5Linked to original sources
PubMed1971

Immunogenicity of purified venezuelan equine encephalitis virus inactivated by ionizing radiation.

Purified and concentrated Venezuelan equine encephalitis (VEE) virus derived from tissue cultures, rendered noninfectious by ionizing radiation with retention of in vitro serological activity, also retained a high level of immunogenicity. In mice, fluid vaccines afforded excellent protection against lethal challenge with homologous Trinidad strain VEE virus. A direct relationship was observed between concentration of vaccine or number of injections and survival. One intraperitoneal inoculation of undiluted vaccine protected essentially all mice challenged 21 days later with 100,000 mouse intraperitoneal LD(50) of virus. Similarly, mice receiving three injections of vaccines diluted 1:100 were completely protected. Noninfectious VEE virus preparations combined with adjuvant 65, a nontoxic metabolizable vehicle, were likewise very effective in protecting mice immunized intraperitoneally or subcutaneously against lethal challenge. Guinea pigs immunized subcutaneously with adjuvant-combined vaccine survived lethal challenge of 1,000,000 guinea pig intraperitoneal LD(50).

Journal Article↗
PubMed1970

Purification, concentration, and inactivation of Venezuelan equine encephalitis virus.

Venezuelan equine encephalitis (VEE) virus was purified and concentrated by chromatography of tissue culture supernatant fluids on diethylaminoethyl-cellulose columns. Stepwise gradient elution studies indicated a broad elution pattern for the virus, with recovery occurring from 0.05 to 0.7 m NaCl. Optical density, infectivity, hemagglutination (HA), and complement fixation (CF) assays indicated that complete recovery of input virus in highly purified form was possible. Single-step elution with 0.7 m tris(hydroxymethyl)aminomethane-succinate-salt buffer resulted in a virus volume decrease of 85% with a concomitant increase in infectivity and antigenicity. Recoveries consistently equaled or exceeded 100% of the input preparations. Additional purification of column-recovered virus was obtained by sedimentation of pooled virus eluates on 50% sucrose cushions. Exposure of borate saline and 0.5% histidine suspensions of purified VEE virus preparations to 6 x 10(6) r of gamma radiation resulted in a loss of infectivity for tissue culture and a loss of lethality for weanling and suckling mice. Inactivation was an exponential function of the dosage. In contrast to infectivity, antigencity (HA and CF) of both saline and histidine preparations was retained after irradiation with doses as high as 6 x 10(6) r. Purified and irradiated VEE virus preparations have been successfully used for routine serological tests and are being evaluated as vaccines.

Agglutination Tests↗
PubMed1969

Ammonium sulfate coprecipitation antibody determination with purified staphylococcal enterotoxins.

The ammonium sulfate coprecipitation technique of Farr was applied in a study of the purified enterotoxins of Staphylococcus aureus. Ammonium sulfate coprecipitation of iodine-131-labeled enterotoxins A, B, and C, with the use of a 1.6 m concentration of (NH(4))(2)SO(4), revealed differences in the antigen-binding capacity of normal and immune rabbit sera for the enterotoxins. The coprecipitation technique provided a quantitative test for detecting antibody to enterotoxin that was more sensitive than agar-gel diffusion methods. Antigen-binding tests suggested the presence of similar antigenic determinant groups in all three toxins. Measurable antigenbinding capacities for enterotoxins A, B, and C were detected in sera of normal human subjects and became elevated in several subjects accidently exposed to enterotoxin.

Animals↗