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Biomedical subjects

H Tsiang

Publications and source records attributed to H Tsiang.

At least 73 records · Page 4Linked to original sources
PubMed1979

Kinetics of different specific immunological parameters after rabies vaccination in mice.

A significant protection to an intracerebral challenge of 70 mean lethal doses of a standard live rabies virus strain was obtained in BCG-pretreated mice or in normal mice which had been immunized with a single subcutaneous injection of a beta-propiolactone-inactivated rabies vaccine. Concomitantly, levels of delayed-type hypersensitivity (measured in vivo by the footpad test) and serum-neutralizing activity were evaluated at various times after immunization. All immune criteria were significantly augmented in the BCG-pretreated, rabies-immune mice as compared to normal, rabies-immune mice. However, peak levels of protection, delayed-type hypersensitivity, and serum-neutralizing activity did not occur at the same times. For instance, in the BCG-pretreated, rabies-immune mice, delayed-type hypersensitivity peaked on day 7, protection peaked on day 21, and serum-neutralizing activity peaked on day 60. In BCG-pretreated mice, which did not receive the rabies vaccine, positive delayed-type hypersensitivity, some protection, and serum neutralizing activity were observed 4 to 5 weeks after BCG pretreatment. The possible relationships between specific and nonspecific immunity provoked by rabies virus antigens, tissue culture cell-associated antigens (derived from the bovine fetal kidney cells in which the rabies virus was grown, and BCG are discussed.

Animals↗
PubMed1978

Inhibition of rabies virus in vitro by the ammonium-5-tungsto-2-antimoniate.

In vitro multiplication of rabies virus was inhibited by a condensed mineral ion, ammonium-5-tungsto-2-antimoniate (HPA 23). The inhibitory effect was evaluated by two different methods, plaque reduction and one step virus growth. Plaquing showed 50% inhibition with 4.5 microgram/ml of HPA 23 and complete inhibition with 12.5 microgram/ml. A reduction of two logs in virus yield was obtained in BHK21C13S cells in suspension treated with 50 microgram/ml of HPA 23. Inhibition also occurred when treatment with HPA 23 was started 18 to 24 h after infection in the plaque assay but no effect was seen when HPA 23 was added 48 h after virus inoculation. All these inhibitory effects of HPA 23 on rabies virus multiplication were observed at non cytotoxic doses. Therefore HPA 23 contrasts with other antiviral drugs which do not inhibit rabies virus multiplication without affecting the viability of cells.

Antimony↗
PubMed1978

Delayed-type hypersensitivity to rabies virus in mice: assay of active or passive sensitization by the footpad test.

With a purified beta-propiolactone-inactivated rabies virus, a significant increase in footpad swelling was elicited in normal or in BCG-pretreated mice after immunization with varying doses of rabies vaccine. These footpad reactions were shown to peak at 24 h and to be associated with an infiltration of newly formed blood monocytes demonstrated by histology and [125I]deoxyuridine labeling. A relationship between the lymphoproliferation and the degree of sensitization is described, and the susceptibility to cyclophosphamide treatment is also examined. Adoptive transfer of specific reactivity to normal recipient mice with immune lymphoid cells, but not with immune serum, was demonstrated, and the results represent another argument for a cell-mediated immunological mechanism.

Animals↗
PubMed1978

Zonal centrifuge purification of human rabies vaccine obtained on bovine fetal kidney cells. Biological results.

An inactivated human rabies vaccine prepared on bovine fetal kidney cells is concentrated and purified by zonal centrifugation. The peak of rabies particles is monitored by hemagglutination. Immunogenicity of the purified particles was evaluated by titration of specific antibodies from vaccinated animals. Protective activity of the vaccine was assayed on guinea pigs challenged with street rabies. Biological results were compared with those obtained with other tissue culture vaccines.

Animals↗
PubMed1978

Delayed type hypersensitivity in mice immunized with inactivated rabies virus.

Evidence of the DTH reaction is in agreement with in vitro observation done with the lymphoblast transformation test in rabbits (5,8) or with the cytotoxicity test in mice (7). The footpad test (FPT) fulfilled all criteria of DTH. A maximum swelling at the injection site was observed 24 h after challenge. FPT could not be transferred by immune serum. But both local and systemic transfer of dissociated spleen cells or lymph node cells sensitized recipient mice to the FPT. A lymphoproliferative response in the draining lymph node was observed after injection of RV, coinciding with the appearance of circulating cells mediating DTH and this response is not dependent upon a B-cell regulatoring mechanism (3). Evaluation of vaccines in vivo by specific DTH reaction is of interest for testing the cell-mediated immunity of these vaccines.

Adjuvants, Immunologic↗
PubMed1976

[Rabies glycoprotein purification by isoelectric focusing (author's transl)].

A glycoprotein was extracted with Triton X100 from rabies virus grown in primary foetal bovine kidney cells. This glycoprotein was further purified by iso electro focusing and showed a major peak at pH 7,0 and a smaller peak at pH 4,6. Purified fractions were migrated on polyacrylamide gels and assayed for immunogenicity.

Glycoproteins↗