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D W Weiss

Publications and source records attributed to D W Weiss.

101 records · Page 6Linked to original sources
PubMed1965

High Susceptibility of Strain A Mice to Endotoxin and Endotoxin-Red Blood Cell Mixtures.

Heppner, Gloria (University of California, Berkeley), and David W. Weiss. High susceptibility of strain A mice to endotoxin and endotoxin-red blood cell mixtures. J. Bacteriol. 90:696-703. 1965.-Strain A mice were shown to be considerably more susceptible to lethal effects of endotoxin lipopolysaccharide (LPS) than mice of several other strains. Complexes of sublethal quantities of LPS and sheep red blood cells were synergistically toxic for strain A mice. Separate administration of sheep red blood cells and heat-killed salmonellae, in either order and as long as 24 hr apart, also proved to be synergistically lethal for strain A mice, but not for R(III) animals studied comparatively. Sheep red blood cell lysates possessed the ability of the intact cells in forming lethal combinations for strain A mice with killed salmonellae. Strain A red blood cell-killed salmonellae complexes were also lethal for strain A mice, but less so then complexes made with sheep red blood cells. A x R(III) F(1) hybrid animals showed the same resistance characteristics as the resistant R(III) parental strain. Possible explanations for these findings are suggested, and their relevance to an immunological mode of action of endotoxin lethality is discussed.

Journal Article↗
PubMedDate not supplied

Restraint stress-induced changes in lymphocyte subsets and the expression of adhesion molecules.

The effect of restraint stress on the distribution of lymphocyte subsets were studied in young BALB/c male mice. Loss of whole body weight, a reduction in the weights of spleen and lymph nodes, and higher levels of serum corticosterone were evident after a single continuous restraint period of 16-18 h. Tissue sections of spleens from restrained animals revealed erythrocyte depletion in the contracted red pulp. Furthermore, there was a significantly higher proportion of CD4+, but not of CD8+, lymphocytes in the spleen. The proportion of the CD4+ subset was markedly diminished in peripheral blood, whereas no changes were detected in lymph nodes. Restraint resulted in enhanced allogeneic mixed lymphocyte reactivity and in altered expression of some CD4+, but not CD8+, splenocyte adhesion molecules (CD44, LFA-1 and VLA-4). Removal of circulating corticosteroids by surgical adrenalectomy abolished the restraint-induced changes in lymphocyte adhesion molecule expression. The findings suggest that the observed differences in lymphocytes subset distribution of lymphoid organs may be due to changes in the pattern of adhesion molecule expression.

Adrenalectomy↗
PubMedDate not supplied

Immunological reactivity to a mycobacterial fraction is associated with nonspecific suppression of immunological responsiveness in vivo.

Previously reported studies revealed that spleen cells from BALB/c mice immunized against a methanol extraction residue (MER) fraction of tubercle bacilli are defective in the in vitro generation of antibodies to SRBC and in allogeneic responsiveness against C57BL spleen cells. We now show that mice repeatedly immunized with MER also exhibit a depressed capacity to respond to antigenic stimulation in vivo. Thus mice repeatedly injected with MER were impaired in their ability to react to antigenic stimulation by SRBC and by C57BL spleen cells. Impairment in the response to SRBC immunization was expressed at the level of delayed-type hypersensitivity (DTH) as well as of antibody production. The response of MER hyperimmunized mice to contact sensitization with dinitrofluorobenzene (DNFB) was not impaired, but the lymph node cells of DNFB-sensitized animals had a depressed ability to respond to in vitro stimulation by the monovalent hapten dinitrobenzene sulfonate (DNBS). The present findings indicate that extensive exposure to an immunogenic immunomodulating mycobacterial fraction can lead to a depressed responsiveness to unrelated antigenic stimulation.

Animals↗
PubMedDate not supplied

Classification of cancer chemotherapeutic drugs according to their ability to potentiate contact sensitivity to dinitrofluorobenzene.

The anticancer chemotherapeutic drugs cyclophosphamide (CY), melphalan (L-phenylalanine mustard; L-PAM), 5-fluorouracil (5-FU), methotrexate (MTX), and daunorubicin (DAU) were tested for ability to potentiate contact sensitization (CS) to dinitrofluorobenzene (DNFB) in mice and to inhibit induction of unresponsiveness to such sensitization by preceding exposure to dinitrobenzenesulfonate (DNBS). Administration of CY and L-PAM but not of 5-FU, MTX, and DAU, after DNBS treatment (and before DNFB sensitization) reduced the degree of unresponsiveness effected by DNBS. It is suggested that the test system of CS might be utilized for screening the ability of cancer chemotherapeutic agents to act as nonspecific immuno-modulators.

Animals↗
PubMedDate not supplied

Animal models of cancer immunotherapy: questions of relevance.

Further progress toward the development of more effective clinical immunotherapy depends on a reasoned formulation of the nature, usages, implications--and pitfalls--of test models in animals and in the test tube; these must be made relevant to themselves and to the conditions of neoplasia in man which they are intended to represent.

Animals↗
PubMedDate not supplied

Effect of treatment with the methanol extraction residue fraction of killed tubercle bacilli (MER) on the development of spontaneous pulmonary metastases from syngeneic implants of tumor 3LL in C57B1 mice.

Treatment of C57B1 mice with the methanol extraction residue fraction of killed tubercle bacilli (MER) shortly before or after surgical removal of a syngeneic implant of lung carcinoma 3LL reduced the incidence of spontaneous, fatally progressing pulmonary metastases in a large number of instances. Under certain conditions, the protective action of MER was pronounced and statistically significant. Small quantities of MER (0.2 mg) were optimally effective, when administered i.p. two days before or one day after excision of the initial implant.

Animals↗