PubMed Health⌕ Search

Biomedical subjects

S Carrel

Publications and source records attributed to S Carrel.

At least 145 records · Page 8Linked to original sources

Use of limitations of radiolabeled anti-CEA antibodies and their fragments for photoscanning detection of human colorectal carcinomas.

Fifty-three patients with histologically proven carcinoma were injected with highly purified [131I]-labeled goat antibodies or fragments of antibodies against carcinoembryonic antigen (CEA). Each patient was tested by external photoscanning 4, 24, 36 and 48 h after injection. In 22 patients (16 of 38 injected with intact antibodies, 5 of 13 with F(ab')2 fragments and 1 of 2 with Fab' fragments), an increased concentration of 131I radioactivity corresponding to the previously known tumor location was detected by photoscanning 36-48 h after injection. Blood pool and secreted radioactivity was determined in all patients by injecting 15 min before scanning, [99mTc]-labeled normal serum albumin and free 99mTc04-. The computerized subtraction of 99mTc from 131I radioactivity enhanced the definition of tumor localization in the 22 positive patients. However, in spite of the computerized subtraction, interpretation of the scans remained doubtful for 12 patients and was entirely negative for 19 additional patients. In order to provide a more objective evaluation for the specificity of the tumor localization of antibodies, 14 patients scheduled for tumor resection were injected simultaneously with [131I]-labeled antibodies or fragments and with [125I]-labeled normal goat IgG or fragments. After surgery, the radioactivity of the two isotopes present either in tumor or adjacent normal tissues was measured in a dual channel scintillation counter. The results showed that the antibodies or their fragments were 2-4 times more concentrated in the tumor than in the normal tissues. In addition, it was shown that the injected antibodies formed immune complexes with circulating CEA and that the amount of immune complexes detectable in serum was roughly proportional to the level of circulating CEA.

Animals↗

[Anti-tumor antibodies in the blood of patients with gliomas].

Anti-tumor antibodies have been searched for with an antibody-dependent cell-mediated cytotoxicity assay in the sera of patients with glioma. Sera from 60 patients and from 25 normal individuals have been tested against cells from 8 human glioblastoma lines. 10 patients (17%) and 5 controls (20%) were found to have antibodies against one or more tumor lines. There were extensive cross-reaction between the positive sera against the different glioma cells, but the reactivity of each serum was different. The specificity of the antibodies thus detected has been investigated. The positive patients' sera were found to have a similar cytotoxic activity against unrelated tumor and normal cells. Moreover, their activity was absorbed by cells from unrelated tumors and normal platelets. These results do not support the concept of a specific humoral response of glioma patients to a possible common tumor-associated antigen.

Antibodies, Neoplasm↗

Rabbit antiserum against Daudi-cell membrane fractions detects cell surface antigens present on subpopulations of human lymphocytes.

An antiserum was produced by immunization of rabbits with membrane preparations of a human lymphoblastoid B cell line, Daudi. After absorption with a human endometrial carcinoma cell line, this antiserum appeared to be specific for antigen(s) present on adult and fetal thymocytes as well as on tonsillar lymphocytes but absent, or present in very small amounts, on normal or phytohemagglutinin- (PHA) stimulated peripheral blood lymphocytes (PBL). When T and B cell-enriched fractions from tonsillar lymphocytes were tested with the anti-Daudi serum, the reactivity was equally distributed in each population. Among 13 human lymphoblastoid cell lines tested, reactivity was demonstrated on three out of four T cell lines, and on four out of nine B cell lines. The positive reacting B cell lines were derived from two African and two American Burkitt lymphomas. The antigen(s) described does not seem to be related either to human Ia-type antigens or to Epstein-Barr virus-associated antigens because these antigens are not present on fetal or adult thymocytes. Reciprocal absorption experiments indicate that this anti-Daudi serum detects the same antigenic structures present on certain subpopulations of T and B lymphocytes.

Absorption↗

Antibody-dependent cell-mediated cytolysis of human colon carcinoma cells induced by specific antisera against carcinoembryonic antigen.

Antibody-dependent lymphocyte cytotoxicity against human colon carcinoma cells grown in vitro was demonstrated with rabbit anti-carcinoembryonic antigen (CEA) antisera and normal human lymphocytes. The same antisera produced no tumor cell lysis in a complement-dependent cytotoxicity test. The specificity of the reaction was demonstrated by the inhibition of antibody-dependent lymphocyte cytotoxicity after the addition of increasing amounts of purified CEA to the antiserum and by the fact that only tumor cell lines expressing CEA on their surface were lysed. Antibody-dependent lymphocyte cytotoxicity was also observed against two colon carcinoma cell lines that expressed Blood Group A antigen, using a human serum containing anti-Blood Group A antibodies of the immunoglobulin G class. This reaction was specifically inhibited by absorption with Blood Group A red cells, whereas the anti-CEA-dependent cytotoxicity was not inhibited by absorption with red cells of different blood groups.

ABO Blood-Group System↗

Establishment of a cell line (Co-115) from a human colon carcinoma transplanted into nude mice.

A human colon carcinoma cell line, Co-115, has been established in vitro from solid xenografts maintained in nude mice and subcultured for 95 passages. Co-115 cells grow in vitro as tightly packed, epithelial-like colonies, have a doubling time of about 36 hr, have a relatively low plating efficiency in agar, and release significant amounts of carcinoembryonic antigen to the culture medium. Their epithelial nature has been confirmed by ultrastructural examination. The injection of Co-115 cells into nude mice reinduced the formation of solid tumor masses that could be retransplanted and showed a morphology comparable of that of the original xenograft.

Adenocarcinoma↗

Human endometrial carcinomas serially transplanted in nude mice and established in continuous cell lines.

Three out of five human endometrial carcinomas were successfully grafted into nude mice (BALB/c/nu/nu). Two of these tumors could be maintained by serial transplantation. The morphological characteristics displayed by the grafted tumors were comparable to those of the original carcinomas. Permanent cell lines were established from these two tumors. Reinjection of cells grown in vitro into nude mice produced nodules of identical histology as compared to original solid transplants. The influence of medroxyprogesterone acetate on tumor growth in vivo and cell proliferation in vitro was studied. This hormonal treatment did not produce any significant effect on tumor cells, either in vitro or in vivo, for the two endometrial carcinomas. After medroxyprogesterone administration, a slight but non-significant growth inhibition of the tumor cells in vitro was observed and the tumor transplants in vivo did not appear to be influenced. The experiments illustrate the possible use of this model for testing potential anti-cancer agents.

Adenocarcinoma↗

Isolation of normal immunoglobulin E by means of an immunoadsorbent.

An improved method for the isolation of normal immunoglobulin E is described. The method is based on the use of an immunoadsorbent formed by the mechanical entrapment of antibodies against a myeloma immunoglobulin E into a lattice of a highly cross-linked macroporous polyacrylamide gel. Normal immunoglobulin E was isolated from an immunoglobulin E-rich serum pool as well as from an individual healthy donor. The isolated immunoglobulin E was contaminated with about 20% of immunoglobulin G. An antiserum against normal immunoglobulin E was prepared by immunizing rabbits with the isolated immunoglobulin E.

Acrylamides↗