Human neuroblastoma cells lack HLA-A,-B,-C molecules which can be induced in vitro by gamma interferon (gamma IFN). To test the hypothesis that the same induction would occur in vivo leading to tumor regression, a Phase I study was initiated. Seven patients with neuroblastoma were entered on a Phase I study of recombinant gamma IFN in children. Three received 0.05 mg/m2 intravenously (IV) three times a week, three received 0.1 mg/m2 for 4 weeks, and one patient withdrew from study before receiving adequate treatment for evaluation. No significant clinical response was seen. The side effects were fever and chills, and no serious toxicity occurred. Natural killer (NK) and lymphocyte activated killer (LAK) precursor activity of peripheral blood mononuclear cells was determined before and during treatment, and expression of HLA-A,B,C molecules was looked for on the tumor cells in the bone marrow of five patients. The NK activity initially low, reached control levels in six patients, but the increase was transient. The LAK precursor activity remained normal. Expression of HLA-A,B,C, initially absent, was induced on the neuroblastoma cells in four of six patients.

Antigens, Neoplasm↗

PubMed1989

Expression of HLA-DR mRNA in T cells following activation is early and can precede DNA synthesis.

The stimulation of T cells is accompanied by the appearance of a number of activation antigens not found on resting T cells. We have studied the expression of one group of such antigens, the HLA class II antigens (DR, DQ and DP), following stimulation with PHA and PMA. Immunofluorescence studies using monoclonal antibodies indicated that cell surface class II determinants were detectable as little as 30 minutes following stimulation, and that their levels remained constant for about 24 hours, after which they began to increase. Studies on the molecule level demonstrated an increase in the steady state levels of mRNA for DR beta by 15 minutes. Immunoblot analysis of resting T cell lysates using a monoclonal antibody reactive with DR detected a polypeptide of approximately 28 KDa, which agrees with the known molecular mass of the light chain of class II molecules on SDS-PAGE, suggesting that the rapid surface expression might have been due to the presence of pre-formed class II polypeptides. These results demonstrate 1) that T cells defined as resting by conventional criteria contain class II polypeptides and 2) that increases in steady state levels of class II mRNA is a very early event which precedes the initiation of DNA synthesis.

DNA Replication↗

PubMed1988

Creating the archives.

Explore the source record for details and available documents.

Archives↗

PubMed1984

Biosynthesis of the glycocinnamoylspermidine antibiotic, cinodine.

The biosynthesis of cinodine from a combination of 14C- and 13C-labeled precursors has been investigated. Tyrosine was shown to be incorporated efficiently into the cinnamoyl moiety and glucosamine was found to be the origin of the three carbohydrate moieties. The relationship between the substrate dose and the enrichment of the labeled antibiotic has been elucidated so that it is possible to predict both the specific activity and the yield of the antibiotic obtained from the labeled substrates.

Aminoglycosides↗

PubMed1980

Pokeweed mitogen inhibition of protein synthesis in cultured lymphoblastoid lines.

Pokeweed mitogen (PWM) and ricin are both lectins derived from plant seeds. They are glycoproteins and share the ability to agglutinate a variety of animal cells including erythrocytes. The effect of these two lectins on protein synthesis was studied in four long-term lymphoblastoid lines (8866 and GM1531, which are B cell lines; and CCRF/CEM and MOLT 4, which are T-cell lines). Ricin (50 micrograms/ml) completely inhibited protein synthesis by 2 hr in both B-cell and T-cell lines as measured by the uptake to [3H]leucine. The PWM appeared more specific and at a concentration of 500 micrograms/ml inhibited protein synthesis only in B-cell lines (8866 and GM1531). This effect was maximal at 5 hr. To investigate the reason for the differential effect of PWM on T and B cells, 125I-labeled PWM was incubated with 8866, MOLT 4, and CCRF/CEM to see if a significant difference in binding to B cells and T cells could be demonstrated. It does not appear that differential effect on T and B cells is due to a difference in the amount of PWM bound. On the other hand it is possible that the B cells may bind some toxic subcomponent of the PWM preparation that the T cells do no bind because of a difference in composition or arrangement of cell surface glycoproteins.

Acetylgalactosamine↗

PubMed1980

Use of monoclonal antibodies in an enzyme-linked inhibition assay for rapid detection of streptococcal antigen.

We have developed an enzyme-linked monoclonal antibody inhibition assay to detect bacterial antigens in cerebrospinal fluid. The monoclonal antibody used in this immunodiagnostic test was produced by continuous cultures of hybrid myeloma cell lines. Using this assay, type III GBS antigen was detected in CSF specimens from 11 culture-proven cases of GBS meningitis and in the knee aspirate from an infant with GBS septic arthritis. Five spinal fluid specimens from meningitis due to other bacterial pathogens and ten other control samples were negative. The ELMIA detected streptococcal antigen at a concentration of 10 ng/ml, and is more sensitive and specific than currently used immunodiagnostic tests.

Animals↗

PubMed1980

Use of monoclonal antibodies in an enzyme immunoassay for rapid identification of group B Streptococcus types II and III.

Streptococci belonging to Lancefield group B are frequently recognized as the etiological agents of sepsis and meningitis in young children. Current methods of identifying these organisms have not been universally accepted because of the time and complexity in performing the studies and a lack of reference antisera. We have developed hybrid myeloma (hybridoma) cell lines which secrete large amounts of antibody against types II and III group B streptococci. Antibodies harvested from supernatants react only with the bacterial strain that was used initially to immunize the animals. We have used the hybridoma antibodies in an enzyme immunoassay and have shown it to be a sensitive and reliable technique for typing group B streptococci. The use of hybridoma antibodies in the enzyme immunoassay may permit early detection of group B streptococcal antigen before cultures are visibly positive.

Animals↗