B. V. Siegel

Vitamin C and the immune response.

The inclusion of vitamin C in the drinking water of BALB/c mice was without effect on the humoral antibody response to sheep red blood cells and bacterial lipopolysaccharide. However, there was a significantly increased cell-mediated immune response as determined by increased T-lymphocyte responses to concanavalin A. This might suggest a mechanism, along with interferon enhancement, for the possible protection by vitamin C against some viral infections.

Suppression of graft-versus-host reaction by phytohemagglutinin

Mit Phytohämagglutinin behandelte Milzzellen erwachsener Mäuse, übertragen auf neugeborene Balb/c-Mäuse, lösen die erwartete « Runt-disease » nicht aus. Versuche mit Milzzellsuspensionen werden diskutiert.

Hematological changes in mice following freund's adjuvant administration.

A single intraperitoneal injection of mice with complete Freunds adjuvant, with and without bovine serum albumin, resulted in transient involution of the thymus and spleen, a wasting syndrome, and an altered peripheral blood picture characterized by lymphopenia and neutrophil granulocytosis. Interestingly, an increased production of antibody was observed during a period of reduced lymphocyte numbers. An analogy has been drawn here to the wasting disease observed in neonatally thymectomized mice.

Reticuloendothelial activity of new zealand black mice.

Summary Carbon clearance rates were observed to be significantly increased in autoimmune NZB mice with enlarged spleens. Similar acceleration could be induced in young NZB mice by intraperitoneal injection of phenylhydrazine 5 days prior to assay. Marked anemia and splenomegaly were also noted to develop following such phenylhydrazine treatment. Splenectomy of 1-year-old NZB mice was observed to result in delayed clearance of carbon particles. There was little effect on the rate of carbon clearance in young NZB mice injected intraperitoneally with a serum pool obtained from old Coombs positive animals. Assessment of spleen and liver radioactivity following intravenous injection of technetium-99m sulfur colloid indicated a somewhat reduced efficiency of colloid uptake by the enlarged spleen on a per milligram weight basis; however, this reduced efficiency was not sufficient, generally, to counteract the increased clearance capacity of the whole organ. The present findings would suggest that the increased rate of carbon clearance observed in overtly autoimmune NZB mice may be a result of the hepatosplenomegaly associated with the disease state. We are grateful to Dr. E. L. Dobson, Donner Laboratory, University of California, Berkeley, for supplying the Pelikan carbon and for his helpful discussions regarding these studies.

Retardation of murine viral leukemogenesis by prolonged antigenic stimulation.

Die Mortalität an Leukämie bei BALB/c-Mäusen wurde durch wöchentliche i.p. Injektionen mit menschlichen Erythrozyten herabgesetzt, wenn sie während 8 Monaten vor der Impfung mitRauscher-Leukämievirus vorbehandelt waren. 7 Monate nach der Virusinfektion zeigten 20% dieser Mäuse keine Zeichen von Leukämie. Kontrollversuche mit der gleichen Serie von Injektionen von Ochsenserumalbumin zeigten keinen Schutz.

Influence of Cytoxan and Poly I·C on Early Antinuclear Antibody Responses in New Zealand Black Mice

Summary Early manifestation of antinuclear antibodies (ANA) in the plasma of NZB mice was significantly depressed by twice weekly injection of 20 mg/kg body weight cytoxan from the age of 9 days. Single injection of 75 mg/kg at 6 or at 13 days of age was ineffective in this regard. Similarly, ongoing ANA responses in 4-month-old NZB mice were undiminished by single injection of 180 or 300 mg/kg of cytoxan. A course of administration of 160 μg of poly I·C followed 24 hr later by 75 mg of cytoxan was repeated three times during a period of 56 days in an attempt to induce tolerance in 2-month-old ANA positive mice. Attenuation of ANA response was demonstrable 2 weeks after initiation of treatment, but was not observed at later times during the study, conceivably a consequence of the anti-DNA activity of the antinuclear antibody assayed. We thank Mrs. Sherrie Fitzgerald for her technical assistance.

Circulating hemagglutinins of new zealand black strain mice immunized with sheep erythrocytes.

Es wird gezeigt, dass der Gehalt an Serumantikörpern nach Immunisation mit Schaferythrozyten in jungen NZB-Mäusen im Vergleich zu BALB/c-Stämmen grösser ist. Diese Unterschiede wurden nach der zweiten und dritten Antigeninjektion geringer. Bei alten Coombs-positiven NZB-Mäusen wird eine Verzögerung der Reaktion nach der ersten, jedoch eine normale Reaktionszeit nach der nun folgenden Injektion gefunden. Die Ergebnisse entsprechen den Resultaten mitJernes Technik bei Reaktionsuntersuchungen antikörperbildender Zellen.

Potentiation of the immunosuppressive effects of cytoxan by hyperbaric oxygen

Die intermittierende Anwendung hyperbarischen Sauerstoffs erhöht die die Antikörper unterdrückende Wirkung von Cytoxan bei Mäusen, die vorher mit Ochsenserum-Albumin und Freunds Adjuvans immunisiert worden waren. Der Wirkungsmechanismus des Sauerstoffs wird als Verhinderung der Transformation von kleinen Lymphocyten in immunbiologisch aktive Stammzellen gedeutet.

Role of heavy water as solvent in the Antigen-Antibody precipitin reaction

Wenn die Lösung zu 50% aus schwerem Wasser bestand, blieb die Bildung von Antigen-Antikörperpräcipitat im Bereich des Antikörperüberschusses unverändert. Dies zeigt, dass die Substitution mit Deuterium die spezifischen Bindungseigenschaften nicht verändert. Dagegen fand sich eine erhöhte Niederschlagsmenge im Bereich des Antigenüberschusses, was auf eine Herabsetzung der Löslichkeit des normalerweise löslichen Antigen-Antikörperkomplexes hinweist.