Biomedical subjects

B Hurtrel

Publications and source records attributed to B Hurtrel.

75 records · Page 5Linked to original sources

PubMedDate not supplied

Systemic candidiasis in mice. I.--Correlation between kidney infection and mortality rate.

After intravenous inoculation of mice with large doses of living Candida albicans, the kidneys are the only organs where multiplication of fungi occurs. After systemic challenge performed with varying doses of yeasts, kidney infection shows an identical pattern during the first 12 h, independently of the magnitude of the inoculum. Destruction of parasites occurs during the first 3 h and then C. albicans begins to multiply. Death occurs when the number of microorganisms in the kidneys exceed 10(5) viable units and the time of death is correlated with renal infection measured 12 h after challenge. An identical correlation is found when mice are pretreated with an immunosuppressor or immunostimulants. No statistical significance is observed in counts of C. albicans in right or left kidney, in males or females, but a slightly higher total count and a lower mean survival time are noted in female mice. These results show that counting C. albicans in kidneys 12 h after systemic infection provides a rapid screening test. In addition, this fact taken with the mortality may explain the nature of the pathological processes which occur during systemic candidiasis in mice.

Animals↗

PubMedDate not supplied

Delayed-type hypersensitivity to sheep red blood cells in selected lines of mice with high or low antibody responses.

Interline differences in DTH to SRBC which developed in high antibody producer (H/Ab) and low antibody producer (L/Ab) genetically selected lines of mice were observed after intravenous (IV) or subcutaneous (SC) sensitization. This interline difference was more marked in female that in male mice, and with the optimal dose for DTH sensitization. The kinetics of the local inflammatory reaction after local challenge, the development and decay of the 24-h DTH reaction tested at varying intervals after sensitization, were always statistically significantly higher in H/Ab than in L/Ab mice. This higher DTH was associated with a higher capacity of these mice to produce a secondary humoral response, and the more marked difference was observed for the production of 2-mercaptoethanol-resistant specific antibodies. Higher DTH reaction in H/Ab mice could not be explained by the participation of either B lymphocytes or humoral antibodies, since high dose (200 mg/kg) of CY injected before IV-SRBC, sensitization, in order to inhibit B-cell activation, did not alter the DTH-interline difference. Moreover, IV injection of specific antibodies from H/Ab immune mice did not enhance DTH in adoptively immunization L/Ab mice. Immune serum alone was not able to adoptively transfer DTH either in H/Ab or in L/Ab mice. Also, a low dose (40 mg/kg) known to inhibit T-cell suppression, injected before SC-SRBC sensitization, was not able to modify the DTH reaction in L/Ab mice. The persisting higher 48-h local inflammatory reaction in H/Ab mice after CY pretreatment was also related to a high blood monocyte rebound. When the afferent arc of the immune response to SRBC was studied in these mice, as tested by the lymphoproliferative response in draining popliteal node after footpad sensitization and by the evaluation of the ability of the T-activated cells located in these draining nodes to transfer locally an adoptively DTH reaction into naive recipients, it was shown that in immunized mice more specifically activated T cells were produced in H/Ab than in L/Ab mice. Moreover, the H/Ab recipients had a higher capacity to develop a local inflammatory reaction than the L/Ab recipients. The mechanisms of these observed interline differences are discussed.

Animals↗

PubMedDate not supplied

[Effect of protein additives in mouse food on immune response to sheep red blood cells in mice (author's transl)].

Protein additives used in mouse food (fish meal, bovine blood meal, milk powder) interfere with the specific immune response induced with sheep red blood cells. Bovine blood meal reduces delayed type hypersensitivity (DTH) reactions and delays IgG production. Blood derivatives suppress mostly the central induction and not the peripheral expression of DTH since depression can be shown after systemic and not after subcutaneous immunization. The suppression of DTH is specific, it did not appear when DTH was produced with antigens presenting no antigenic cross-reactivity with protein additives (chicken red blood cells, tuberculin). This depressive effect was related neither to the presence of inhibitory serum factor nor to the production after immunization of specific antigen-antibody-blocking factor. Blood derivatives seem to act on the afferent arc of immune response especially on the splenic immunogenicity of the injected antigen to produce DTH.

Animals↗