Search PubMed⌕ Search

Biomedical subjects

Sam Hanash

Publications and source records attributed to Sam Hanash.

10 recordsLinked to original sources

Computational Proteomics Analysis System (CPAS): an extensible, open-source analytic system for evaluating and publishing proteomic data and high throughput biological experiments.

The open-source Computational Proteomics Analysis System (CPAS) contains an entire data analysis and management pipeline for Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS) proteomics, including experiment annotation, protein database searching and sequence management, and mining LC-MS/MS peptide and protein identifications. CPAS architecture and features, such as a general experiment annotation component, installation software, and data security management, make it useful for collaborative projects across geographical locations and for proteomics laboratories without substantial computational support.

Computational Biology↗

Global and distinct targets of IRF-5 and IRF-7 during innate response to viral infection.

The interferon regulatory factors (IRF) are transcriptional mediators of cellular response to viral invasion that play a critical role in the innate antiviral defense. Two of these factors, IRF-5 and IRF-7, play a critical role in the induction of interferon (IFNA) genes in infected cells; they are expressed constitutively in monocytes, B cells, and precursors of dendritic cells (pDC2) that are high producers of interferon alpha, and their expression can be further stimulated by type I interferon. The goal of the present study was to identify and analyze expression of cellular genes that are modulated by IRF-5 and IRF-7 during the innate response to viral infection. The transcription profiles of infected BJAB cells overexpressing IRF-5 or IRF-7 were determined by using oligonucleotide arrays with probe sets representing about 6800 human genes. This analysis shows that IRF-5 and IRF-7 activate a broad profile of heterologous genes encoding not only antiviral, inflammatory, and pro-apoptotic proteins but also proteins of other functional categories. The number of IRF-5- and IRF-7-modulated genes was significantly higher in infected than in uninfected cells, and the transcription signature was predominantly positive. Although IRF-5 and IRF-7 stimulated a large number of common genes, a distinct functional profile was associated with each of these IRFs. The noted difference was a broad antiviral and early inflammatory transcriptional profile in infected BJAB/IRF-5 cells, whereas the IRF-7-induced transcripts were enriched for the group of mitochondrial genes and genes affecting the DNA structure. Taken together, these data indicate that IRF-5 and IRF-7 act primarily as transcriptional activators and that IRF-5-and IRF-7-induced innate antiviral response results in a broad alteration of the transcriptional profile of cellular genes.

Blotting, Western↗

HUPO initiatives relevant to clinical proteomics.

The past few years have seen a tremendous interest in the potential of proteomics to address unmet needs in biomedicine. Such unmet needs include more effective strategies for early disease detection and monitoring and more effective therapies, in addition to developing a better understanding of disease pathogenesis. Proteomics is particularly suited for investigating biological fluids to identify disease-related alterations and to develop molecular signatures for disease processes. However, much of the effort undertaken in clinical proteomics to date represents either demonstrations of principles or relatively small-scale studies when compared with genomics effort and accomplishments or more pertinently when contrasted with the tremendous untapped potential of clinical proteomics. Clearly, we are in the early stages. What seems to be urgently needed is an organized effort to build a solid foundation for proteomics that includes developing a much needed infrastructure with adequate resources. The Human Proteome Organization (HUPO) is fostering an organized international effort in proteomics that includes initiatives around organ systems and biological fluids that have disease relevance as well as development of proteomics resources.

Humans↗

Disease proteomics.

The sequencing of the human genome and that of numerous pathogens has opened the door for proteomics by providing a sequence-based framework for mining proteomes. As a result, there is intense interest in applying proteomics to foster a better understanding of disease processes, develop new biomarkers for diagnosis and early detection of disease, and accelerate drug development. This interest creates numerous opportunities as well as challenges to meet the needs for high sensitivity and high throughput required for disease-related investigations.

Disease↗

Intact-protein based sample preparation strategies for proteome analysis in combination with mass spectrometry.

The complexity of tissue and cell proteomes and the vast dynamic range of protein abundance present a formidable challenge for analysis that no one analytical technique can overcome. As a result, there is a need to integrate technologies to achieve the high-resolution and high-sensitivity analysis of complex biological samples. The combined technologies of separation science and biological mass spectrometry (Bio-MS) are the current workhorse in proteomics, and are continuing to evolve to meet the needs for high sensitivity and high throughput. They are relied upon for protein quantification, identification, and analysis of post-translational modifications (PTMs). The standard technique of two dimensional poly-acrylamide gel electrophoresis (2D PAGE) offers relatively limited resolution and sensitivity for the simultaneous analysis of all cellular proteins, with only the most highly abundant proteins detectable in whole cell or tissue-derived samples. Hence, many alternative strategies are being explored. Numerous sample preparation procedures are currently available to reduce sample complexity and to increase the detectability of low-abundance proteins. Maintaining proteins intact during sample preparation has important advantages compared with strategies that digest proteins at an early step. These strategies include the ability to quantitate and recover proteins, and the assessment of PTMs. A review of current intact protein-based strategies for protein sample preparation prior to mass spectrometry (MS) is presented in the context of biomedically driven applications.

Animals↗

Building a foundation for the human proteome: the role of the Human Proteome Organization.

Proteomics holds both substantial promise and substantial challenges. For proteomics to bear fruit on a large scale from a disease investigation point of view, it is essential to build a solid foundation for the field. Given the magnitude of the challenges, it is necessary to build a foundation by bringing together the private and public sectors. The Human Proteome organization is promoting the field of proteomics by engaging in such an effort and is developing several major initiatives.

Antibodies↗

Development of natural protein microarrays for diagnosing cancer based on an antibody response to tumor antigens.

The detection of autoantibodies to tumor antigens has potential utility for the early diagnosis of cancers. In previous studies, we have identified tumor antigens based on Western blot analysis of tumor cell lysates that were incubated with subject sera to identify proteins that elicit specific reactivity in sera from patients with the corresponding tumor type. More recently, we have explored the use of microarrays spotted with tumor proteins as an alternative to Western blots. Microarrays provide a high throughput, high sensitivity alternative to the use of Western blots for tumor antigen profiling. In this study, we have assessed the reproducibility of natural protein microarrays and their ability to distinguish between lung cancer sera and controls. Protein lysates from the A549 human lung adenocarcinoma cell line were separated into 1840 fractions that were spotted in duplicate, along with various controls, on nitrocellulose coated slides. Sera from 18 newly diagnosed patients with lung cancer and from 15 healthy controls were each hybridized to an individual microarray. The reactivity of arrayed proteins with Ig was determined by incubation with biotinylated goat-anti-human-Ig followed by phycoerythrin-conjugated streptavidin. The intensity measures of duplicate spots (within-slide) and duplicate slides (between-slides) were highly reproducible, exhibiting correlation values >0.9. A total of 63 of the 1840 arrayed fractions demonstrated increased reactivity in cancer patients relative to controls as measured by a rank-based statistic (p < 0.008). Microarrays of tumor-derived proteins provide the means for uncovering a repertoire of tumor antigens that have induced an antibody response in patients with specific cancers.

Adenocarcinoma↗