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J Bubeník

Publications and source records attributed to J Bubeník.

At least 127 records · Page 7Linked to original sources
PubMed1979

Inhibition of cell-mediated cytotoxicity against tumor-associated antigens by suppressor lymph node cells from mice bearing methylcholanthrene-induced sarcomas.

Suppression of cell-mediated cytotoxicity directed against tumor-associated membrane antigens of methylcholanthrene (MC)-induced sarcomas by lymph node cells (LNC) from tumor-bearing mice was examined by inhibition of the 3H-thymidine incorporation assay. Normal LNC from B10 mice had been sensitized in vitro by 6-day cultivation on layers of irradiated syngeneic sarcoma cells and the effect of the generated cytotoxic lymphocytes was then inhibited by the admixture of suppressor cells present in lymph nodes of tumor-bearing mice. Suppressor cells were detected in lymph nodes from 7 of 16 (44 per cent) individually examined tumor bearers when LNC were added to cytotoxic lymphocytes which had been presensitized in vitro. When the experimental schedule was reverted and the tumor bearers' LNC were admixed to the normal LNC prior to the in vitro sensitization so that they were present in the population of the effector cells throughout the period of sensitization, the suppressor effect was detected in only 1 of 9 (11 per cent) tumor-bearers. The suppressive effect of tumor bearers' LNC was found to be nonspecific, being elicited not only by LNC derived from bearers of the sensitizing tumor, but also by LNC from bearers of an unrelated, immunologically noncross-reacting MC-induced sarcoma.

Animals↗
PubMed1979

Technical aspects of the macrophage electrophoretic mobility test in transplantation immunity.

Transplantation immunity against a product of the D-region of mouse H-2 gene complex was examined by the macrophage electrophoretic mobility assay. The results obtained with the MEM assay depended upon selection of the guinea pig peritoneal exudate macrophages used for measurements. The macrophages 16--20 micrometers in diameter and containing liquid paraffin droplets were best suited for electrophoretic mobility measurements. The cells, containing liquid paraffin droplets but smaller than 16 micrometers in diameter, were affected by lymphocyte-antigen interaction product(s) much less. The increasing antigen concentration resulted in a sharp rise of macrophage percentage slowing from zero but reached a plateau value. The critical number of lymph node cells for a significant response was not less than 10(5) cells and there was a direct relationship between the number of lymphocytes and the magnitude of the response.

Animals↗
PubMed1979

Cell-mediated immune reactions directed against syngeneic methylcholanthrene-induced mouse sarcomas: low reproducibility of the results obtained with the tube modification of leukocyte adherence inhibition assay.

The value of the tube modification of leukocyte adherence inhibition (LAI) assay for assessment of cell-mediated reactions directed against tumor-associated antigens of transplantable MC-induced murine sarcomas was examined. It was established that the adherence of leukocytes isolated from spleens of tumor-bearing mice is specifically inhibited with 3 M KCl extracts of corresponding tumor cells. However, the reproducibility of the results obtained with the tube modification of LAI assay was found to be rather low. Using the same experimental protocol and the same 3 M KCl extracts of the sarcoma and control tissues, significant differences between adherence in tumor specific and control samples were only found in approximately 50% of the experiments.

Animals↗
PubMed1979

Cell-mediated cytotoxicity of adherent and non-adherent mouse lymph node cells sensitized in vitro against tumour-associated antigens of syngenetic methylcholanthrene-induced sarcomas.

Cell-mediated cytotoxicity of adherent and non-adherent subpopulations of mouse lymph node cells sensitized in vitro on monolayers of syngeneic, methylcholanthrene-induced sarcoma cells was examined by inhibition of 3H-thymidine incorporation. The cell-mediated cytotoxicity of nylon wood-adherent, non-adherent and unfractionated lymph node cells was found to be equally efficient.

Animals↗
PubMed1979

Cell surface adhesiveness of mouse sarcoma lines evaluated by latex particle adherence assay: correlation with growth behavior and electrophoretic mobility.

Using the latex particle adherence assay and five mouse sarcoma cell lines of the identical origin, etiology and genotype but differing in malignancy we attempted to correlate the degree of cell surface adhesiveness with growth behavior and electrophoretic mobility of cells. Higher tumorigenicity of four of the cell lines (Mc11--Mc14) was associated with lower cell surface adhesiveness and, conversely, lower malignancy of the fifth line (Mc15) with higher cell surface adhesiveness. No simple correlation or causal relationship was found among the electrophoretic mobility of the lines and other cellular characteristics.

Animals↗
PubMed1978

In vitro immunization against tumour-associated antigen of methylcholanthrene-induced sarcoma.

Lymph node cells obtained from B10 mice were sensitized in vitro on monolayers of syngeneic methylcholanthrene-induced sarcoma cells. The in vitro sensitized LNC displayed specific cytotoxic and inhibitory effects on sarcoma cells used for sensitization. The effects were detectable by visual counting and inhibition of 3H-thymidine incorporation. The inhibition observed after admixture of in vitro sensitized LNC was more effective than inhibition produced by LNC from mice immunized with the same syngeneic sarcoma in vivo. Solubilization of sarcoma cells with 3M KCl gave rise to antigenic preparation which was unable to sensitize syngeneic LNC under experimental conditions used.

Animals↗
PubMed1978

Influence of heparin and defibrase on transplantability of syngeneic tumors in mice.

It had been previously demonstrated that fibrin clot might have an important role in the growth of malignant tumors and in metastasis formation. For this reason an attempt had been made to find out whether inhibition of fibrin formation by heparin or fibrinolysis induced by defibrase could limit tumor growth. Male mice of inbred strain were challenged with suspension of tumor cells. For anticoagulation and/or fibrinolytic therapy two different schedules were used. The treatment was started either simultaneously with the tumor transplantation, or one week prior to the injection of tumor cells. The size of tumors was bigger in the group of treated animals, when compared with the controls. However, the difference was not statistically significant. On the other hand, frequency of implanted tumors was significantly higher in animals with heparin and defibrase treatment or pretreatment.

Animals↗
PubMed1978

Human urinary bladder carcinoma cell line (T24): immunological studies and search for oncornavirus in T24 cell population and derived clones.

Cytotoxicity of mononuclear cell (MNC) preparations isolated from peripheral blood of patients with urinary bladder carcinomas of a transitional (BTCC) or squamous (BSCC) type and from blood of control subjects was examined on the target cells of T24 cell line. In pilot experiments the percentage of cytotoxic MNC preparations was found to be similar in patients with tumors of BTCC (European, 56%;African, 60%) and BSCC (54%) type. Cytotoxicity of MNC prepared from control subjects was detected in 10% of cases or less. These data suggest an antigenic cross-reactivity between urinary bladder carcinomas of transitional and squamous cell type. The cytotoxic MNC from peripheral blood of patients with BTCC and control subjects were fractionated by adherence in nylon wool columns, and the cytotoxicity of adherent and nonadherent MNC subpopulations was examined. In the majority of cytotoxic MNC preparations from both donors with and without BTCC, the cytotoxic activity was associated with nonadherent MNC. Comparison of immunosensitivity of T24 cell population with the cloned T24 subpopulations indicated that clones with various digrees of immunosensitivity are present in the T24 cell population. However, immunosensitivity of the clones was never higher than the immunosensitivity of the T24 cell population. A search for oncornavirus particles produced spontaneously or after treatment with virus production activators performed with regard to the possible association of oncornaviruses and antigens responsible for cell-mediated cytotoxicity gave thus far negative results.

Adult↗
PubMed1977

Immunological response of patients with tumors of the urogenital tract: a follow-up of cell-mediated antitumor immunity by the LAI test.

Antigen-induced inhibition of leukocyte adherence is a suitable method providing information on immunological response of the tumor bearers. Leukocytes from patients' blood were tested by an in vitro method to detect cell-mediated antitumor immunity. Positive reactions of leukocytes to the specific antigen were found in carcinoma of the uterine cervix, vulva and ovary in 13 patients. The modified LAI test evaluated on the basis of free cells in Eagle's medium using the specific antigen is a simplified reversed method which, however, keeps the specificity.

Female↗
PubMed1976

Cell surface antigens detected in cell lines established from lymphomatous Papio hamadryas and Macaca arctoides monkeys.

Cell surface antigens associated with bone marrow cell cultures from leukemic monkeys of species Papio hamadryas and Macacus arctoides were visualized by means of an indirect immunofluorescence method with sera from leukemic baboons. The same immune serum gave two types of immunofluorescence, depending on the origin of the target cells. Fluorescence of the ring-reaction type was seen with Papio hamadryas bone marrow cell cultures growing in suspension and containing the baboon herpesvirus, whereas the patchy type of fluorescence was noted with monolayer bone marrow cell cultures from Macaca arctoides origin, containing type-C oncornavirus but not the herpesvirus particles. Absorption experiments showed that antibodies responsible for the patchy type of immunofluorescence could be absorbed with a disintegrated type-C baboon oncornavirus, and not with baboon lymphoblastoid cell lines containing the herpesvirus nor with human lymphoblastoid cell lines containing the Epstein-Barr virus.

Animals↗
PubMed1975

Cell-mediated tumour immunity in patients with transitional cell carcinoma of the urinary bladder.

Some recent data on problems of cell-mediated immune reaction directed against tumour-associated antigens (TAA) of transitional cell carcinomas of the urinary bladder (BTCC) are reviewed. All of the 13 samples of BTCC examined in our laboratory using a lymphocytotoxicity microassay contained the characteristic TAA of urinary bladder carcinomas. TAA were absent in 14 control tissue samples. Forty-seven out of 70 (67%) patients with BTCC developed cytotoxic lymphocytes reacting with BTCC cells. However, cytotoxic lymphocytes were also found in the blood of 8 out of 165 (4.8%) control lymphocyte donors.

Antigen-Antibody Reactions↗
PubMed1975

Tumour cell destruction by macrophages from conventional animals.

Peritoneal exudate cells (PEC) from conventional donors displayed in vitro the cytotocix effects on the rat sarcoma cell lines LWI3K2, LW13K3, LW13K4 and RSL but they were not cytotoxic to fibroblasts derived from normal rats of the same strains. PEC were also cytotoxic to human urinary bladder carcinoma cells (T-24) grown in vitro. Cytotoxicity was detectable already at the effector to target cell ratio of 1 : 1, and the effector cells from syngeneic, allogeneic and xenogeneic donors were equally effective. The cytotoxic effect was apparently exerted by macrophages because the addition of lymphocytes from PEC donors did not change the target cells. The addition of serum from PEC donors to a mixture of target and effector cells protected the tumour cells from the destruction by macrophages. Cytotoxicity was blocked by serum from all PEC donors tested (syngeneic, allogeneic and xenogeneic with regard to the target cells) but not by foetal calf serum.

Animals↗
PubMed1975

Effect of prophylactic and therapeutic administration of BCG vaccine on growth of experimental sarcoma.

The effect of prophylactic and therapeutic administration of BCG vaccine on growth of transplantable sarcomas induced by MSV-Harvey (MSVT1) and 3-methylcholanthrene (MC 11 and MC 12) in C57BL/10Sn mice was studied. Growth of MSVT1 sarcomas was not inhibited by oral or intratumoral BCG therapy. Nor was prophylactic oral administration of BCG followed by therapeutic oral BCG treatment effective. On the other hand, intradermal administration of an adequate dose of BCG vaccine preceding the tumour transplantation inhibited tumour growth. The low (0.05-0.2 mg.) doses of BCG induced resistance comparable to the effect of subcutaneous immunization with tumour cells, whereas the higher (0.5-1.0 mg) doses had no effect. Growth of MC 11 and MC 12 tumours was not affected by prophylactic intradermal BCG administration.

Administration, Oral↗