Scoring and summarising gene product clusters using the Gene Ontology.

We propose an approach for quantifying the biological relatedness between gene products, based on their properties, and measure their similarities using exclusively statistical NLP techniques and Gene Ontology (GO) annotations. We also present a novel similarity figure of merit, based on the vector space model, which assesses gene expression analysis results and scores gene product clusters' biological coherency, making sole use of their annotation terms and textual descriptions. We define query profiles which rapidly detect a gene product cluster's dominant biological properties. Experimental results validate our approach, and illustrate a strong correlation between our coherency score and gene expression patterns.

Evaluation of soluble CD30 as an immunologic marker in heart transplant recipients.

CD30 is an immunologic molecule that belongs to the TNF-R superfamily. CD30 serves as a T-cell signal transducing molecule that is expressed by a subset of activated T lymphocytes, CD45RO+ memory T cells. Augmentation of soluble CD30 during kidney transplant rejection has been reported. Our study sought to determine whether the level of sCD30 prior to heart transplant could categorize patients into high versus low immunologic risk for a poor outcome. A significant correlation was observed between high levels of soluble CD30 and a reduced incidence of infection. None of the 35 patients with high pretransplant levels of sCD30 level (>90 U/mL) developed infections posttransplantation. However, 9 of 65 patients who had low levels of sCD30 (<90 U/mL) developed infections posttransplantation (P < .02). No remarkable differences were noted among the other clinical parameters. The results also showed that the high-definition flow-bead (HDB) assay detected both weak and strong class I and class II HLA antibodies, some of which (weak class II HLA Abs) were undetectable by the anti-human globulin cytotoxicity method. In addition, more antibody specificities were detected by HDB. In conclusion, we have observed that high levels of sCD30 prior to heart transplant may be associated with greater immunologic ability and therefore produce a protective effect on the development of infection post heart transplant. We have also shown that the HDB assay is superior to the visual cytotoxicity method to detect HLA antibodies, especially those to class II HLA antigens.