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M Walencka

Publications and source records attributed to M Walencka.

10 recordsLinked to original sources
PubMed2001

Influence of dendritic cells on the in vitro allogeneic cytotoxic reaction of lymphoid cells derived from normal or Listeria innocua-infected BALB/c mice.

The role of lymphoid dendritic cells (DCs) in the development of an allogeneic cytotoxic reaction in vitro was examined. The T+B and T cell subsets originating from the spleens or lymph nodes of normal and Listeria innocua-infected BALB/c mice were used as the effector cells. Their cytotoxicity to 51Cr-labeled C3H fibroblasts was determined after removal of DCs and replacing them again. Moreover, the influence of exogenous mrIL-12 on the potency of DCs in the allogeneic reaction developed in vitro was checked. It was found that the DC-deprived T+B or T subsets of splenocytes, regardless of their origin, exhibited 27-38% lower cytotoxicity than those accompanied by natural DCs. The cytotoxicity of these subsets from normal lymph nodes decreased by 22%, while the activity of bacteria-primed cells dropped by 38%. Replenishing effector cells with isolated DCs restored their cytotoxicity. Pulsation of normal DCs with IL-12 had no effect on the recovery of normal cell cytotoxicity. However, the IL-12-pulsed DCs were able to intensify the cytotoxicity of T+B subsets derived from the spleens or lymph nodes of L. innocua-infected mice. The results suggest that the alloantigen presentation by DCs to cytotoxic lymphocytes also takes place in the reaction developed in vitro, regardless of effector cell origin.

Animals↗
PubMed1997

Interleukin 12 and direct cytotoxicity of spleen lymphocytes to Listeria innocua-phagocyting syngeneic macrophages in C57BL/6 and BALB/c mice.

Production of interleukin 12 (IL-12) during cytotoxic reaction of C57BL/6 and BALB/c spleen lymphocytes or their subpopulations: T+B, T, CD4+ and CD8+ cells to L. innocua-phagocyting syngeneic macrophages was examined. The effector cell donors were untreated or L. innocua-infected. The number of surviving bacteria in phagocytes was tested and IL-12 level in culture supernatants of reacting cells was determined. C57BL/6 mice, resistant to Listeria infection, were found to develop stronger cell cytotoxicity to bacteria-phagocyting syngeneic macrophages than BALB/c mice. The lymphocytes responsible for that phenomenon were of CD8+ phenotype. IL-12 was produced only during nonspecific cytotoxic reaction of CD4+ and CD8+ T cells. It is suggested that the innate resistance of mice to Listeria is dependent on their ability to develop a specific cytotoxic reaction and IL-12 production.

Animals↗
PubMed1995

Participation of IL-2 and direct cell cytotoxicity in the modulation of GvH reaction in mice infected with Listeria innocua.

Listeria innocua can intensify the development of local GvH reaction in a semiallogeneic system in mice. This phenomenon is observed in (BALB/c x AKR)F1 mice intraperitoneally injected with the live bacteria on the 7th day before the transfer of BALB/c spleen cells. The local GvH reaction develops as strongly as in normal hybrid recipients given the parental cell graft in the presence of exogenous interleukin 2 (IL-2). The development of the reaction is associated with an intensive increase of the direct cytotoxicity of lymph node cells which is also markedly enhanced after the bacteria injection itself. IL-2 seems to play a relevant role in the development of local GvH reaction in L. innocua-injected mice.

Animals↗
PubMed1994

Effect of cyclosporine A (CsA), cyclophosphamide (Cy) and azathioprine (Aza) on the survival of Listeria innocua in mice.

Immunosuppressors reducing the defensive mechanisms of the organism make favourable conditions for the development of different infections, particularly for intracellular facultative bacteria such as Listeria. In this paper, the effects of different doses of cyclosporine A (CsA), cyclophosphamide (Cy) and azathioprine (Aza) on the survival of Listeria innocua, a nonpathogenic strain, in the peritoneal cavity and spleen of BALB/c mice, were investigated. It was found that CsA and Aza, applied on total doses: 50-250 micrograms/g or 20-100 micrograms/g respectively, before or on the day of bacteria injection, prolong their longer survival as a result of reduced elimination. In CsA treated animals the number of survived Listeria is higher in the spleen while in Aza treated animals--in the peritoneal cavity. The Cy effect appeared to be the weakest because only the immunosuppressive (300 micrograms/g) dose was able to significantly enhance the survival of L. innocua both in the peritoneal cavity and the spleen. The results are a warning for clinicians applying the immunosuppressor treatment.

Animals↗
PubMed1986

Immunomodulatory effect of Listeria monocytogenes infection. I. Allotransplantation reaction in infected mice.

The rejection reaction of skin graft in Listeria monocytogenes infected mice was examined in the allogeneic system: recipient Balb/c mice (haplotype H-2d) and donor G3H mice (haplotype H-2k). It was observed that this reaction was significantly potentiated when skin allograft was transplanted in the period of the highest monocytosis and the strongest delayed type hypersensitivity to Listeria monocytogenes antigen in the infected recipients. This finding suggests that the allotransplantation reaction in Listeria monocytogenes infected organism may be intensified by the activated monocyte-macrophage lineage cells cooperating with the lymphocytes sensitized to Listeria antigen.

Animals↗
PubMed1986

Immunomodulatory effect of Listeria monocytogenes infection. II. Natural cell cytotoxicity in infected mice.

The natural cell cytotoxicity of blood leukocytes, splenocytes and peritoneal cells derived from Balb/c mice being on day 1, 3, 5, 7, 9 of listeriosis to allogeneic fibroblast L 929 was examined. The intensity of cytotoxic reaction was assessed by the per cent of specific 51Cr release from target cells. To check if this reaction correlates with the level of monocyte-macrophage lineage cells present in the effector cells of if it depends on the development of delayed type hypersensitivity to Listeria antigen, Balb/c mice were infected with Listeria monocytogenes and simultaneously treated with ATS. It was found that Listeria monocytogenes infection in mice enhanced the natural cell cytotoxicity of tested effectors cells, particularly of peritoneal cells in animals being on the 5th-7th day of listeriosis. The treatment of mice with ATS which is known to inhibit the development of delayed type hypersensitivity to Listeria antigen, completely suppressed the stimulatory effect of this infection on the natural cell cytotoxicity to allogeneic fibroblasts. This finding suggests that the enhancement of natural cytotoxic activity of tested effector cells results from the action of activated macrophages cooperating with Listeria sensitized T lymphocytes.

Animals↗
PubMed1986

Immunomodulatory effect of Listeria monocytogenes infection. III. Expression of Fc receptor and antibody-mediated cytotoxicity in infected mice.

The level of cells expressing Fc receptor and their ability to antibody mediated cytotoxicity was determined in this study. The adherent cells fraction isolated from blood leukocytes, splenocytes and peritoneal cells of Listeria monocytogenes infected Balb/c mice were rosetted with Ab-SRBC or SRBC. Moreover, blood leukocytes, splenocytes and peritoneal cells were incubated with Ab-51Cr SRBC and 51Cr SRBC as target cells and their cytotoxic activity was assessed by the per cent of specific 51Cr release. The results indicate that in the Listeria infected organisms the level of cells rosetting with Ab-SRBC is greatly increased particularly in peritoneal cells between the 3rd and 7th day of infection i.e. in the period of intensive production of macrophages. Only peritoneal cells exhibit the antibody dependent cytotoxicity. However, the intensity of this cytotoxicity does not correlate with the level of cells expressing Fc receptor.

Animals↗
PubMed1983

Antimonocyte serum. Preparation and characterization.

Cell suspensions enriched with monocytes were obtained from the blood of Vietnam normal pig and rabbits injected with avirulent Welshimer strain of L. monocytogenes by velocity sedimentation on BSA gradient and separation on Ficoll-Triosil gradient. They were used for immunization of rabbits and a sheep, respectively. The antisera specific for monocytes (RAMS and SAMS) were obtained by scrupulous absorption with lymphocytes and granulocytes.

Animals↗
PubMed1983

Antimonocyte serum. The effect on blast transformation, RFC and PFC formation.

The paper is a continuation of the previous experiments. The results show that the rabbit and sheep antisera specific for monocytes after absorption with leukocytes deprived of phagocytosing cells do not affect E-rosetting cells and do not impair the blast transformation of normal leukocytes stimulated by PHA in vitro. However, they reduce the number of EAC rosettes formed by leukocytes and they decrease the ability of leukocytes to produce antibodies for SRBC.

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