Suppressor cells in the effector phase of autologous cytotoxic reactions in cancer patients

Summary Cytotoxicity was induced in lymphocytes (CL) from 10 out of 15 patients by autologous mixed lymphocyte tumor cell culture and further cultivation with recombinant interleukin-2. In cells from 3 of the 10 patients, cytotoxicity was suppressed by more than 50% when autologous peripheral blood mononuclear cells (PBMC) from the patients with large tumors were added to the autologous killing system. The cells responsible for suppressing the cytotoxicity in the effector phase were adherent or nonadherent to plastic depending on the patient examined. The T cell fraction from 1 patient significantly suppressed the cytotoxic activity, and this suppression was seen only in the autologous system. On the other hand, plastic adherent cells but not T cells from PBMC of 2 subjects suppressed the cytotoxic activity of CL. The reason why the main cell population suppressing the CL activity differed among the patients is unclear. However, the findings that the suppression was mostly abrogated following resection of the tumor mass suggested that suppressor cells, either of macrophage lineage or T cells, are induced in patients with a large tumor mass. This speculation is supported by the finding that the PBMC from a patient with tumor recurrence regained the suppressive activity.     

Relationship between susceptibility and immune response to staphylococcal exfoliative toxin A in mammalian species

Staphylococcal exfoliative toxin A (ETA) had a splitting effect at the granular layer of skin in humans and neonatal mice, but not in rabbits, guinea pigs, golden hamsters, or rats. Besides its splitting effect, ETA could stimulate productions of neutralizing antibody to ETA in rabbits, rats and B10D2 mice, but not in golden hamsters, guinea pigs, or ICR, HRS/J, and C57BL/10 mice. In our epidemiological investigation of human sera, the percentage of antibody to ETA in sera obtained from patients with impetigo (8%) was lower than those in sera of healthy males (23%) and females (29%). The relationship between susceptibility and immune response to ETA in these mammalians could be divided into three groups: the possession of resistant skin and high production of antibody to ETA; the possession of resistant skin and low production of antibody to ETA; the possession of sensitive skin and various titers of antibody to ETA.     

Killer cells induced by stimulation with allogeneic tumor cells and subsequent culture with recombinant interleukin-2

Summary Peripheral blood lymphocytes were cultured for 5 days with allogeneic tumor cells (allogeneic mixed lymphocyte/tumor cell culture), and subsequently cultured with recombinant interleukin-2 for 12 days. These cultured cells were found to be cytotoxic to autologous tumor cells. Results of two-color analysis using monoclonal antibodies to cell markers showed that more than 80% of their cultured cells were CD3⁺ cells, and CD4⁺ cells showed a higher distribution than CD8⁺ cells. However, CD8⁺ cells had a much higher killing activity with autologous tumor than did CD4⁺ cells, when estimated by an elimination study using monoclonal antibodies to T cell phenotypes and complement. The cold-target inhibition test showed that the cytotoxicity of these cells for autologous tumor cells was inhibited by unlabeled autologous tumor cells but not by unlabeled stimulator cells. Furthermore, about 40% of the cytotoxicity was suppressed by blocking of HLA class I antigen with a monoclonal antibody on autologous tumor cells. Thus, cytotoxic activity of lymphocytes to autologous tumor restricted by target cell HLA class I antigen is possibly induced by allogeneic tumor-stimulation.     

Cell wall constituents of Leuconostoc citrovorum and Leuconostoc mesenteroides

The cell wall constituents of Leuconostoc citrovorum 8082, L. mesenteroides 10830a, and L. mesenteroides 11449 have been ascertained. All three strains contained glycerol. Glucose and rhamnose were the major reducing sugar constituents. Alanine, glutamic acid, lysine, glucosamine, and muramic acid were the principal amino acids and amino sugars in all three strains. In addition, strain 10830a contained l-serine as a major cell wall component. Quantitative amino acid analyses indicate that glutamic acid, lysine, glucosamine, muramic acid, and serine may be present in the cell walls in equimolar amounts and that alanine is present in three to four times these quantities. The similarities and differences between the cell wall constituents of the leuconostocs and those of the lactobacilli and streptococci are discussed.     

Paper chromatographic system for the identification of glycerol in bacterial cell walls

Ikawa, Miyoshi (University of New Hampshire, Durham), James W. Morrow, and Sheila J. Harney. Paper chromatographic system for the identification of glycerol in bacterial cell walls. J. Bacteriol. 92:812-814. 1966.-The solvent system consisting of isopropanol-5% boric acid (7:1, v/v) separates glycerol from the other carbohydrate constituents which are found in hydrolysates of bacterial cell walls. This system is useful for the identification of glycerol even when anhydroribitol and rhamnose are both present, and has been found to be applicable on cell wall hydrolysates as well as on synthetic mixtures.