Biomedical subjects

Y P Sher

Publications and source records attributed to Y P Sher.

3 recordsLinked to original sources

PubMed1998

Treatment of B-cell lymphoma with chimeric IgG and single-chain Fv antibody-interleukin-2 fusion proteins.

Anti-idiotype (Id) antibodies (Abs) have been shown to be effective in treatment of B-cell lymphoma in animal models and in clinical trials. The combination of interleukin-2 (IL-2) can augment the therapeutic effect of anti-Id Abs. To further improve the power of the combined therapy, a monoclonal anti-Id Ab, S5A8, specifically recognizing a murine B-cell lymphoma 38C13, was genetically modified to contain the IL-2 domain and thus use the unique targeting ability of Abs to direct IL-2 to the tumor site. Two forms of the anti-Id-IL-2 fusion proteins were constructed: one configuration consisting of mouse-human chimeric IgG (chS5A8-IL-2) and the other containing only the variable light (VL) and variable heavy (VH) Ab domains covalently connected by a peptide linker (scFvS5A8-IL-2). Both forms of the anti-Id-IL-2 fusion proteins retained IL-2 biological activities and were equivalent in potentiating tumor cell lysis in vitro. In contrast, the antigen-binding ability of scFvS5A8-IL-2 was 30- to 40-fold lower than that of the bivalent chS5A8-IL-2. Pharmacokinetic analysis showed that scFvS5A8-IL-2 was eliminated about 20 times faster than chS5A8-IL-2. Finally, it was shown that chS5A8-IL-2 was very proficient in inhibiting 38C13 tumor growth in vivo, more effectively than a combined therapy with anti-Id Abs and IL-2, whereas scFvS5A8-IL-2 did not show any therapeutic effect. These results demonstrate that the anti-Id-IL-2 fusion protein represents a potent reagent for treatment for B-cell lymphoma and that the intact IgG fusion protein is far more effective than its single-chain counterpart.

Adjuvants, Immunologic↗

PubMed1998

Profiling expression patterns and isolating differentially expressed genes by cDNA microarray system with colorimetry detection.

A high-density cDNA microarray with colorimetry detection system to simultaneously monitor the expression of many genes on nylon membrane is described and characterized. To quantify the expression of genes and to isolate differentially expressed genes, the southern hybridization process on filter membranes was employed. The levels of gene expression were represented by color intensities generated by colorimetric reactions in place of hazardous radioisotopes or costly laser-induced fluorescence detection. The gene expression patterns on nylon membranes were digitized by devices such as an economical flatbed scanner or a digital camera. The quantitative information of gene expression was retrieved by image analysis software. Quantitative comparison of the northern dot-blotting method with the microarray system is described. Applications employing single-color detection as well as dual-color detection to isolate differentially expressed genes among thousands of genes are demonstrated.

Blotting, Northern↗

PubMed1998

Detection and quantitation of circulating cancer cells in the peripheral blood of lung cancer patients.

Detection and quantitation of circulating cancer cells in peripheral blood may improve cancer staging and monitoring. This study explored the feasibility of using circulating cancer cell detection in peripheral blood for the rapid assessment of chemotherapeutic response. Cytokeratin 19 mRNA was amplified by nested reverse transcriptase-PCR in the peripheral blood of 29 healthy volunteers, 33 pneumonia patients, and 86 lung cancer patients. Circulating cancer cells in the peripheral blood were semiquantitatively determined by taking the ratio of cytokeratin 19 band intensity from the second round of nested PCR to the glyceraldehyde-3-phosphate dehydrogenase band intensity from the first round of PCR amplification. The detection limit of the method was 1 cancer cell in 107 peripheral blood mononuclear cells. The positive detection rate was 40% for lung adenocarcinoma patients of all stages, 41% for squamous carcinoma patients of all stages, and 27% for small cell lung cancer patients. Only one control sample from a pneumonia patient showed a positive result (1.6%). The quantitative method reliably and sensitively estimated cancer cell numbers in the peripheral blood of lung cancer patients. Serial measurement of the relative number of circulating cancer cells correlated with the tumor burden and treatment response of patients. This method may help rapidly assess the efficacy of anticancer treatment, redefine cancer staging, and facilitate the design of better therapeutic strategies for the treatment of cancer patients.

Adult↗