Studies on Carcinoembryonic Antigen

In a previous communication, carcinoembryonic antigen (CEA) of rat, which is an analogue to human CEA, was demonstrated in gastrointestinal adenocarcinomas induced in inbred Fischer rats by injection of 1,2-dimethylhydrazine. Antibodies detectable by enzyme immunoassay were elicited in Fischer rats by immunization with a perchloric acid extract of the CEA-containing rat tumor, RCA-1, incorporated into Freund’s complete adjuvant. Specificity studies showed that activity of the rat antisera could be virtually abolished by inhibition with the tumor extract used at a concentration of 25 μg/ml. Inhibition by newborn rat tissues required extract at a concentration of 250 μg/ml. Extracts of normal adult tissues did not inhibit at these concentrations, but did inhibit at a concentration of 2,500 μg/ml. The results showed that rat CEA, though present in low concentration in normal adult rat tissue, is capable of eliciting an immune response in rats.

Section: Introductionmentioning

confidence: 99%

“…Preliminary data have been pre sented at national meetings [ 14,15]. The tumors were propagated by injecting weanling Fischer rats under the skin of the back with 108 viable tumor cells suspended in Medium 199 containing penicillin and streptomycin.…”

Section: Introductionmentioning

confidence: 99%

Induction of Antibodies in Rats to a Rat Carcinoembryonic Antigen

Sa¹,

Cj²,

Milgrom³

1985

“…For con trols, sera of 100 blood donors and 24 healthy staff members of this department were included; they too gave negative results. Perchloric acid extracts (PAE) [5] of 12 cancer tissues and saline extracts (SE) of 11 lymphoma-leukemia spleen specimens ob tained at 100 C were also examined. PAE of 3 cancer tissues and SE of 2 spleens gave positive results in agglutination-inhibition tests.…”

mentioning

confidence: 99%

Paul-Bunnell Antigen in Malignancies and Rheumatoid Arthritis

Nishimaki¹,

Kano²,

Milgrom³

1979

By means of agglutination inhibition test, Paul-Bunnell (P-B) antigen was demonstrated in sera of patients with cancer (5%), lymphomas or leukemias (12.5%) and rheumatoid arthritis (RA) (1.4%) as well as in synovial fluids from RA patients (27%). In contrast, none of 124 normal human sera gave positive results. P-B antigen was also demonstrated in 3 of 12 perchloric acid extracts of cancer tissues and 2 of 11 saline extracts obtained at 100°C from spleens of lymphoma-leukemia patients. Extracts of apparently normal tissues from 16 individuals gave negative results.

“…However, specificity for the diagnosis of tuberculosis should be solved [9], Classically, PCA was used for the extraction of glyco protein from samples. Carcinoembryonic antigen was de tected in PCA extracts of colonic tumors [24], Kim et al [13] found that after the extraction of biological specimens with PCA, the IgG or its fragments demonstrable by ELISA in the original preparations which might elicit pos itive reactions in control wells were not demonstrated in the extracts.…”

Section: Discussionmentioning

confidence: 99%

Analysis of Perchloric-Acid-Soluble <i>Mycobacterium bovi</i><i>s</i> Bacille bilié de Calmette-Guérin Antigen

Kim

1993

The perchloric-acid-soluble Bacille bilié de Calmette-Guérin (BCG) antigen (BCG-P) was investigated for the diagnosis of tuberculosis. Monoclonal antibodies against BCG-P were produced. After SDS-PAGE, silver staining and immunoblotting were done. Pathological specimens of pulmonary tuberculosis, BCG organism itself and atypical mycobacterium were stained using the indirect immunofluorescent technique with the strongest one among these monoclonal antibodies. Intradermal skin test and ELISA were also done with BCG-P. BCG-P was composed of a major 65-kD protein and a minor 61-kD protein. Fourteen monoclonal antibodies were produced which were all IgM. These antibodies reacted with the 65-kD protein which also showed cross-reactivity with Mycobacterium tuberculosis in pathologic tissues and atypical mycobacterium. BCG-P did not react with the sera of patients with active pulmonary tuberculosis. However, intradermal skin test with BCG-P showed positive reactions in the patients with a positive purified protein derivative of tuberculin skin test. This antigen could be a good antigen to evaluate the success of BCG vaccination.