Search PubMed⌕ Search

Biomedical subjects

C E Pedersen

Publications and source records attributed to C E Pedersen.

47 records · Page 3Linked to original sources
PubMed1974

Effects of antigen-antibody complexes on the primary immune response in Rhesus monkeys.

A model for the enhancement of the primary humoral immune response of rhesus monkeys to marginal or weakly antigenic vaccines is presented. Our procedure used the complexing of formalin-inactivated Venezuelan equine encephalomyelitis (VEE) virus vaccine with specific, homologous, immune gamma globulin (IgG) at equivalence. Equivalence was determined by combining the concentrated, isotopically labeled ((3)H) virus with various concentrations of specific Sephadex-fractionated IgG. Enhancement of VEE virus antibody response in monkeys was obtained from preparations containing a marginal concentration of antigen that was complexed at equivalence with homologous IgG as compared with antigen alone. Protection in Swiss mice closely paralleled the antibody response pattern observed in monkeys, since complexes at equivalence provided 30 to 50% greater protection against challenge than antigen alone.

Animals↗
PubMed1974

Separation, isolation, and immunological studies of the structural proteins of Venezuelan equine encephalomyelitis virus.

Three viral proteins were separated from the TC-83 strain of Venezuelan equine encephalomyelitis virus by discontinuous polyacrylamide gel electrophoresis after disruption with sodium dodecyl sulfate and beta-2-mercaptoethanol. These proteins were inoculated into rabbits and the resultant antisera were tested for immunological activity by gel precipitation, plaque reduction neutralization, hemagglutination inhibition (HI), complement fixation, fluorescence microscopy, and mouse protection studies. All proteins were capable of stimulating precipitating antibody in rabbits, but the largest protein (VP 1), which is contained in the envelope, stimulated the production of detectable neutralizing and HI antibody against the intact virion. The other two proteins yielded little or no neutralizing or HI antibody.

Animals↗
PubMed1972

Chromatography of Venezuelan equine encephalomyelitis virus strains on calcium phosphate.

Column chromatography of selected Venezuelan equine encephalomyelitis (VEE) viruses on calcium phosphate gel offered a simple and reproducible method for examination of biochemical characteristics and relatedness of strains within the VEE complex. Members of antigenic subgroup I demonstrated a series of elution profiles within a narrow range of 0.22 to 0.25 M phosphate buffer. Members of antigenic subgroups II, III, and IV differed substantially among themselves and viruses of antigenic subgroup I. These differences in elution behavior may contribute to understanding of observed differences in biological behavior and antigenic variation among VEE viruses.

Calcium Phosphates↗
PubMed1972

Early protection in hamsters immunized with attenuated Venezuelan equine encephalomyelitis vaccine.

The rapid onset and persistence of homologous and heterologous protection induced by attenuated Venezuelan equine encephalomyelitis (VEE) vaccine (TC-83) were studied in the hamster, by using challenge response as the index of protection. At 8 hr postvaccination with 10(3) median immunizing doses of TC-83 vaccine, 15 to 20% of animals were protected against challenge with VEE virus as well as Eastern and Western equine encephalomyelitis viruses. The percentage of protection increased with time postvaccination until 80 to 90% homologous and heterologous protection was achieved by 18 hr postvaccination. Temporal studies indicated that early protection (days 1 to 6) correlated with vaccine viremia, and that the percentage of protection against heterologous challenge decreased with the cessation of viremia. Data are presented to indicate that the early protection phenomenon is one of interference, since little or no replication of a challenge virus occurred when it was administered during the vaccine viremia stage.

Animals↗
PubMed1972

Comparative studies of plaque variantes derived from a Florida strain of Venezuelan equine encephlomyelitis virus.

Small- and large-plaque variants of a Florida strain (Fe 3-7c) of Venezuelan equine encephalomyelitis virus were studied in vivo and in vitro. The small-plaque variant was less virulent in mice, hamsters, and guinea pigs than the large-plaque variant. The variants could be distinguished by calcium phosphate chromatography. The implications of plaque variants within a mixed virus population are discussed.

Animals↗