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Biomedical subjects

H J Rapp

Publications and source records attributed to H J Rapp.

At least 91 records · Page 5Linked to original sources
PubMed1976

Development of an assay for aryl hydrocarbon (benzo(a)pyrene) hydroxylase in human peripheral blood monocytes.

An assay has been developed and measurements of aryl hydrocarbon [benzo(a)pyrene] hydroxylase have been made in peripheral blood monocytes from a human population. Treatment with benz(a)anthracene in cell culture increased aryl hydrocarbon hydroxylase activity from 6.5 to 37-fold in monocytes from each of 25 apparently healthy donors. A weak correlation (r = 0.38) was observed between the induction ratios obtained with monocytes and lymphocytes from the same donors. Reproducibilities of the monocyte and lymphocyte assays were comparable. In monocytes, the measurement of basal and induced aryl hydrocarbon hydroxylases activity does not require pretreatment with mitogens as is the case with lymphocytes. Monocytes also exhibit a much wider range of induction ratios than do lymphocytes.

Adult↗
PubMed1975

Protective tumor immunity induced by potassium chloride extracts of guinea pig hepatomas.

Tumor-specific antigens of cells of the diethylnitrosamine-induced hepatomas in strain-2 guinea pigs were extracted with 3 M KCl. Immunization of normal animals with the extracted tumor antigens in adjuvant protected them against a subsequent challenge with viable tumor cells. Extracted tumor-specific antigens were less effective immunogens than viable tumor cells for both of two antigenically distinct lines.

Animals↗
PubMed1975

Extraction of tumor-specific antigen from cells and plasma membranes of line-10 hepatoma.

Tumor-specific antigen was extracted with 3 M KCl from line-10 guinea pig hepatoma cells. The yield of antigenic activity, estimated by production of delayed cutaneous hypersensitivity reactions in line-10 immune guinea pigs, was 10-30% of the antigen present in intact cells. By ultracentrifugation criteria, the extracted antigen was soluble. Gel filtration, ion exchange chromatography, and salting-out studies showed that the antigen was heterogeneous in size and net charge. The possibility that 3 M KCl extracted a homogeneous population of molecules associating into polymers of various sizes at low ionic strength was ruled out by heterogeneity on Sephadex G-200 chromatography at high ionic strength. After osmotic lysis of sucrose-loaded line-10 cells, whole plasma membranes or large membrane fragments were obtained in a yield of about 20%. The isolation procedure did not cause detectable loss of membrane antigenic activity. The membranes had 33 skin test U/mg membrane protein, compared to the intact cell value of 1.7 skin test U/mg cell protein. Extracts of plasma membranes had 10-20% of the antigenic activity of the starting membrane material. In contrast to the wide variety of proteins liberated from intact cells, much of the protein extracted from the membranes was in the molecular weight range above 250,000.

Animals↗
PubMed1975

Local antitumor activity of a primary and an anamnestic response to a syngeneic guinea pig hepatoma.

After intradermal (id) injection, the line-10 hepatoma grew progressively in nonimmune guinea pigs, whereas the line-1 hepatoma grew for approximately 2 weeks, developed central necrosis, ulcerated, and regressed. Growth of the line-10 hepatoma was suppressed when line-10 hepatoma cells were mixed with antigenically distinct line-1 hepatoma cells before id injection into syngeneic strain-2 guinea pigs. Mixture of line-10 with irradiated line-1 or viable strain-2 embryo cells did not inhibit tumor growth. Preimmunization of recipients to line-1 cells abrogated the suppression of tumor growth from mixtures of line-1 and line-10.

Animals↗
PubMed1975

Eradication of microscopic lymph nodes metastases after injection of living BCG adjacent to the primary tumor.

Guinea pigs with established intradermal tumors and microscopic axillary lymph node metastases were treated with a combination of surgery and BCG. The tumors were excised and BCG was given in attempts to eliminate residual malignant disease. Injection of BCG into established intradermal tumors 7 days before local excision successfully eradicated microscopic axillary lymph node metastases and cured significant numbers of animals. Injection of BCG into dermal tumors 20 minutes or 1 day before excision prolonged survival but did not cure a significant number of animals. Injection of BCG into the skin adjacent to the dermal tumor 7 days before local excision eradicated microscopic axillary lymph node metastases. However, such injection 1 day before local excision did not eradicate metastases. BCG administered by intravenous, intra-arterial, or intranodal injection did not eliminate reidual malignant disease. Several factors were evaluated as possible correlates of successful immunotherapy. The development of tuberculin hypersensitivity, the magnitude of regional adenopathy, and the number of BCG organisms in axillary nodes were not useful correlates. Histologically, the presence of tumor cells, multiple focal granuloma, or histiocytosis in axillary nodes faiiled to correlate with results of therapy. The development of tumor-specific transplantation immunity provided the best correlate of successful immunotherapy.

Adjuvants, Immunologic↗
PubMed1975

Quantitative comparison of techniques used to measure complement-mediated cytotoxicity of nucleated cells.

?The cytotoxicity of nucleated cells by specific antibody and complement can be guantitated in vitro by several methods. Trypan blue exclusion, 51-Cr release, inhibition of uptake of 3-H-thymidine, and inhibition of colony formation are the four assays that we used to guantitatively compare the C-mediated cytotoxicity of Chinese hamster lung (CHL) cells. CHL cells were sensitized with either guinea pig or rabbit anti-CHL antisera, and exposed to guinea pig, human, or rabbit C. We found that the relative activities of the antibodies and the complements were not dependent on the method of measurement of cytotoxicity, i.e., a given pair of antiserum-complement were not dependent on the method of measurement of cytotoxicity, i.e., a given antiserum-complement titer, regardless of the assay used to measure cytotoxicity. However, the titers of the different antibody-complement pairs differed from each other.

Animals↗
PubMed1975

Antitumor activity of bacterial infection. II. effect of Listeria monocytogenes on growth of a guinea pig hepatoma.

Growth of a guinea pig hepatoma was suppressed when tumor cells were mixed with viable Listeria monocytogenes (LM) before intradermal (id) injection into syngeneic recipients. Heat-killed LM were less effective than viable organisms in suppressing tumor growth. A vaccine containing oil droplets and LM cell walls lacked antitumor activity. Intratumor injection of viable LM on the 7th day after id injection of tumor cells prolonged survival of guinea pigs that did not succumb to LM infection. After intratumor injection of 0.6 times 10-8-1.0 times 10-8 LM, 5 of 22 guinea pigs died from acute infection (23 percent). In the 17 survivors, 3 tumors regressed completely (18 percent). Animals surviving injections of LM and tumor cells were immune to a second challenge with tumor cells. Immunization ofguinea pigs with an intravenous injection of LM decreased the mortality from intratumor injection of LM, but the intratumor injection of LM failed to cure a significant fraction of LM-immune animals bearing 7-day hepatoma transplants. BCG was more effective than LM in producing tumor regression. Synergism between LM and BCG was not observed, and simultaneous intratumor injection of BCG and LM was no more effective than intratumor injection of BCG alone in the treatment of 12-day tumor transplants.

Animals↗
PubMed1975

Suppression and regression of a transplanted tumor in the guinea pig colon mediated by Mycobacterium bovis, strain BCG.

The growth in the colon wall of a diethylnitrosamine-induced hepatocarcinoma was suppressed by BCG. Injection of BCG into established colon-wall tumors caused tumor regression. Successful therapy required a limited tumor burden. Guinea pigs in which growth of the neoplasm was suppressed at the site of BCG infection developed systemic tumor transplantation immunity.

Animals↗
PubMed1975

Antitumor activity of bacterial infection. I. Effect of Listeria monocytogenes on growth of a murine fibrosarcoma.

Growth of a murine fibrosarcoma was suppressed when tumor cells were mixed with viable Listeria monocytogenes (LM) before intradermal injection into nonimmune syngeneic recepients. Immunization of recipients, by intravenous injection of LM 11 days before transplantation of LM-tumor cell mixtures, eliminated the mortality associated with large doses of LM but did not alter the antitumor activity of the microorganisms. Simultaneous injection of LM and tumor cells at separate sites failed to affect tumor growth, which suggested that contact between LM and tumor cells was required for tumor suppression. Tumor-specific immunity was not observed; mice surviving injection of LM and tumor cells did not resist a second tumor-cell challenge. At least 100 times more heat-killed LM was required to produce the antitumor effect of viable organisms. The ability of heat-killed LM to suppress tumor growth was abolished by treatment of recipients with rabbit antiserum to mouse thymocytes, which was consistent with a requirement for a host response to the LM. Regression of established fibrosarcoma transplants was produced by the intratumor injection of viable LM 5 days after injection of tumor cells. Intratumor injection of BCG at this interval was not effective. The incidence of tumor regression was not increased by multiple intratumor injections of LM, by intratumor injection of a combination of LM and BCG, or by preimmunization with LM prior to the intratumor injection of the same organism.

Animals↗
PubMed1974

BCG and cancer.

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Anaphylaxis↗