Immunologic control of a retrovirus-associated murine adenocarcinoma. VI. Augmentation of antibody-dependent killing following quantitative and qualitative changes in host peritoneal cells.

Attempts were made to augment the antibody-dependent killing of the ascitic AD755a tumor in vivo to protect C57BL/6J mice against the outgrowth of larger tumor burdens. The lethal dose for this tumor is less than 100 cells, and antibodies contained in a hyperimmune antitumor serum (HIS) were found to suppress the outgrowth of a maximum of about 5 X 10(5) cells. Thioglycollate injected ip increased the number of peritoneal macrophages, potential effectors for antibody-dependent cell-mediated cytotoxicity (ADCC), by tenfold to fortyfold and raised the maximum treatable tumor challenge (MTTC) to about 4 X 10(6) cells.

[Initial polychemotherapy in the treatment of cancers of the head and neck. The efficacy and tolerance of 2 nonrandomized combinations in 48 patients].

Before loco regional treatment for head and neck cancer forty eight patients received one or the other of the following combined chemotherapy regimens: Regimen A (28 patients): high dosage methotrexate, bleomycin, cis-platin; regimen B (20 patients): common dosage methotrexate, bleomycin, hydroxyurea, vincristin. The effectiveness of regimen A seemed better than that of regimen B (46% responses versus 20%). This assessment must be accepted with caution, since, although the organization of treatment was strictly similar in the two groups, the study was not randomized, and there were noticeable differences between the two groups.

Immunologic control of the ascites form of murine adenocarcinoma 755. V. Antibody-directed macrophages mediate tumor cell destruction.

An in vitro assay has been developed that mimics the potent in vivo protective capacity of B6 anti-AD755a serum in a passive therapy protocol. In the presence of small volumes of hyperimmune serum or IgG2a antibody, thioglycollate-elicited B6 mouse peritoneal cells (PEC) inhibit the growth of AD755 Cl.10 target cells and other cells provided that they express FLV-related antigens.

Morphological and biochemical properties of a new human breast cancer cell line.

DU4475 is a new human breast cell line derived from a cutaneous metastatic nodule from a patient with advanced breast cancer. It has been in continuous culture for more than 1 year and has survived 140 subcultivations. The cells grow in suspension, displaying clusters and free-floating aggregates with serpentine-like outgrowths.

[Non resectable colonic cancer. Results from a test of chemotherapy with simultaneous prescription of VM26, methyl-CCNU and 5 fluoro-uracile (author's transl)].

Thirty nine patients with non resectable colonic carcinoma entered into a phase II combination chemotherapy trial. The patients were treated with a sequential cyclic combination of 3 drugs: VM 26 (60 mg/m2), methyl-C.C.

Virus-infected avian cell lines established in vitro.

Four virus-infected avian cell lines have been established in culture. Two of these lines, infected with BAI strain A virus, liberate only small quantities of virus in the culture fluid. The cells retain the ability to induce myeloblastic leukemia when inoculated i.

Isolation of two subgroup-specific leukemogenic viruses from standard avian myeloblastosis virus.

Two populations of virus having subgroup-specific homogeneity (A and B) were isolated from standard avian myeloblastosis virus stocks by passage in vivo through genetically defined chickens. Each possesses leukemogenic activity in vivo. Other properties and potential usefulness of these agents are discussed.

Component of strain MC29 avian leukosis virus with the property of defectiveness.

Three clones of morphologically altered cells (L(-)MC29) of singular properties were isolated from MC29 (subgroup A) leukosis virus-infected chick embryo cells. Supernatant fluids from cultures of the cloned cells produced no transforming or interfering activity on chick embryo cells susceptible to known avian leukosis-sarcoma viruses. No virus associated with the cells was demonstrable by fluorescent-antibody staining or by electron microscopy.

Reaction of chick embryo cells infected with leukosis strain MC29 virus with fluorescein-labeled antibody.

Immune serum was prepared in the rabbit with BAI strain A leukosis virus isolated by centrifugal fractionation from the plasma of chickens with myeloblastic leukemia and further purified on a potassium tartrate gradient. Antibody to group-specific antigen was demonstrated in the serum by immunoelectrophoresis and immunodiffusion. Fluorescein-conjugated serum was used unabsorbed and absorbed with chick cells for study of acetone-fixed chick embryo cells uninfected or infected with strain MC29 avian leukosis virus.