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M R Price

Publications and source records attributed to M R Price.

At least 181 records · Page 10Linked to original sources

Tumor-associated and embryonic antigens in soluble fractions of a chemically-induced rat colon carcinoma.

Soluble intracytoplasmic protein fractions and solubilized tumor membrane preparations produced by 3 M KC1 or papain treatment were isolated from a 1,2 dimethylhydrazine-HC1 (DMH)-induced rat colon carcinoma, DHM-BU 1. Solubilized preparations were fractionated by DEAE cellulose and Sephadex G200 column Chromatography. Crude extracts and fractionated materials were tested for their ability to inhibit the cytotoxicyt of lymph-node cells (LNC) from rats bearing isografts of an N-methyl-N-nitro-N-nirosoguanidine (NG)-induced colon carcinoma, ng-W1...

Adenocarcinoma↗

Detection of hepatoma associated embryonic antigen in tumour-bearer serum.

Embryonic antigen associated with an aminoazo dye-induced rat hepatoma was identified in the serum from rats bearing progressively growing tumours. Antigenic activity in serum samples was detected by their capacity to neutralize multiparous rat serum antibody reacting with surface embryonic antigens expressed upon viable hepatoma cells as assessed with use of the indirect membrane immunofluorescence test. Serum taken at various states of tumour growth from hepatoma-bearing rats was separated by Sephadex G-150 gel filtration column chromatography at pH 7.3 and pH 2.8 with use of procedures designed to identify free circulating antigen and antigen derived from immune complexes. Hepatoma-associated embryonic antigen was demonstrable in tumour-bearer serum in a free form most markedly in the later stages after implantation of tumour cells (from the end of the 2nd week to the 5th week of tumour growth). Antigenic activity in fractions derived from immune complexes was detected earlier during tumour development (from day 8 after tumour induction), and this was present in all serum samples taken up to the 5th week after tumour cell inoculation.

Animals↗

Preparation of aminoazo dye induced rat hepatoma membrane fractions retaining tumour specific antigen.

Membrane fractions were isolated from homogenates of an aminoazo dye induced rat hepatoma (hepatoma D23) by sucrose density gradient centrifugation in zonal rotors. The membrane fractions retained tumour specific antigenic determinants and exhibited an increased antigenic activity over other subcellular membrane fractions, as defined by their capacity to quantitatively neutralize the membrane immunofluorescence staining of viable hepatoma D23 cells by antibody in tumour immune serum. In contrast, no antigenic activity was found to be associated with purified hepatoma D23 nuclei or nuclear membranes as evaluated by the in vitro antigen assay.The two methods described for the isolation of hepatoma D23 membranes have been developed for the large scale fractionation of tumour homogenates in order that further studies upon the nature and immunogenicity of membrane associated tumour specific antigens may be resolved using defined membrane preparations of increased antigenic activity.

Animals↗

Immunogenic properties of rat hepatoma subcellular fractions.

Subcellular fractions from an aminoazo dye induced rat hepatoma (D23) were examined for their ability to evoke rejection responses in syngeneic hosts to transplanted tumour cells and to induce the production of humoral antibody. Membrane fractions isolated by zonal centrifugation and displaying an increased activity of tumour specific antigen (Price and Baldwin, 1974), as well as crude membrane fractions and purified tumour cell ghosts, all elicited tumour specific antibody demonstrable by membrane immunofluorescence staining of viable hepatoma D23 cells. Tumour cell nuclei or soluble cytoplasmic protein were, however, lacking in this capacity. Resistance to tumour cell challenge was not observed in rats treated with any of the hepatoma D23 subcellular fractions administered by various routes either alone or in admixture with bacterial adjuvants. These findings are relevant to current views that tumour immunity may be more optimally achieved by inoculation of intact (viable or attenuated) tumour cells.

Animals↗

Inhibition of leucocyte migration in patients with large intestinal cancer by extracts prepared from large intestinal tumours and from normal colonic mucosa.

The degree of migration inhibition in response to tissue extracts has been examined in leucocyte preparations obtained from patients with large intestinal cancer and from age and sex matched control individuals. A greater degree of migration inhibition was observed in response to a colorectal tumour extract in cells obtained from the cancer patients. Inhibition also tended to be more marked in response to the tumour extract than in response to a normal colonic mucosal extract in these patients. These results suggest that altered cellular immune reactivity is demonstrable by this simple in vitro technique in patients with large intestinal cancer.

Aged↗