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Biomedical subjects

A Calogero

Publications and source records attributed to A Calogero.

45 records · Page 3Linked to original sources

The transcriptional factor Egr-1 is synthesized by baculovirus-infected insect cells in an active, DNA-binding form.

The Egr-1 (zfp-6) gene encodes a zinc-finger-containing nuclear protein that is rapidly and transiently induced in quiescent cells treated with mitogens. We have constructed baculovirus vectors that synthesize mouse Egr-1 protein initiating at two putative ATG start sites. The ATG site producing the larger protein (Mr, 80,000) is similar, if not identical, to Egr-1 synthesized by serum-stimulated quiescent mouse fibroblasts, thus identifying the likely site for translation. The protein synthesized by the insect cells is active as assayed by its ability to bind to a specific DNA sequence that has been identified as an Egr-1 binding site. The insect cell system will allow further studies of the structure and function of the Egr-1 product, a protein that appears to be an important "master switch" for other genes.

Animals↗

Recombinant T-cell receptors: an immunologic link to cancer therapy.

Cytotoxic T cells can specifically kill target cells that express antigens recognized by the T-cell receptor. These are membrane-bound proteins that are not ubiquitous and thus are difficult to purify and study at the protein level. The advent of recombinant DNA technology has facilitated these objectives, thereby enabling researchers to gain valuable information about major T-cell receptor characteristics. Genetic manipulation of T-cell receptors has also been used to exploit specificity of killing by cytotoxic T lymphocytes, which represents an attractive feature for therapeutic purposes. The objective of this review was to provide an overview of the major strategies adopted to genetically manipulate T-cell receptors.

Animals↗

Retargeting of a T cell line by anti MAGE-3/HLA-A2 alpha beta TCR gene transfer.

BACKGROUND: The T cell receptor (TCR) is an heterodimeric protein on the cell membrane of cytotoxic T cells (CTLs). In CTLs TCRs mediate the recognition of target cells through interaction with specific, MHC class I presented peptides. MATERIALS AND METHODS: As a model system to show proof of principle we chose the Jurkat/MA cell line and the HLA-A2.1 binding MAGE-3 derived peptide 271-279, as target specificity. RESULTS: We show that this cell line can be successfully transduced with the dicistronic retroviral vector (LZRS) containing cDNAs encoding for the complete alpha and beta chains of the selected TCR. Following retroviral transduction, Jurkat/MA cells do express the anti-MAGE-3 TCR on their membrane. The transduced TCR is functional as travoductants are successfully triggered, upon stimulation with T2 cells or MAGE-3+ melanoma cells loaded with the MAGE-3 peptide. CONCLUSION: We conclude that TCR gene transfer is possible and it represents a powerful therapeutic tool for the genetical modification of T calls of patients sullering from cancer.

Antigens, Neoplasm↗

Effect of specific or random c-DNA priming on sensitivity of tyrosinase nested RT-PCR: potential clinical relevance.

The reverse transcriptase polymerase chain reaction (RT-PCR) can be of clinical relevance in identifying malignant melanoma cells in blood or tissues of patients at risk for disseminated melanoma. The diagnostic value of this marker however, is still controversial. The objective of this study was to compare and quantify the difference in sensitivity of the nested RT-PCR for tyrosinase, with respect to the method utilized to produce the template c-DNA. We found a difference of a factor 10 in favor of a specific priming versus a random one. We concluded that this difference can be exploited in the analysis of blood samples. However, in the analysis of lymph node specimens, where the chance of positivity due to tyrosinase positive non-melanoma cells is much higher, the choice of a highly sensitive assay should be made with caution.

Biomarkers, Tumor↗