Optimization of biologic therapy in Crohn's disease.

INTRODUCTION: Crohn's disease (CD) is a manifestation of inflammatory bowel disease (IBD), which can result in significant morbidity. Biologic therapy with anti-TNF medication has been effective in treating inflammation and reducing complications in CD. It is important for clinicians to have better knowledge of the various biologic therapies including mechanisms of action and optimization strategies. AREAS COVERED: The review describes optimization of biologic therapy in CD including different mechanisms of loss of response, therapeutic drug monitoring in CD, clinical implications and management strategies which utilize drug monitoring, and areas of future development and research in optimization of biologic therapy. EXPERT OPINION: Achieving adequate levels of the drug (antibody unbound) is one of the most important determinants of attaining clinical remission and mucosal healing. Drug level is also critical in determining if a patient requires combination therapy with an immunomodulator. Certain populations, including those with active perianal disease, may require higher serum levels to achieve healing or closure. Treat to target level is an algorithm that is not universally accepted and more data is need. Additionally, there are numerous assays that don't always correlate, especially regarding measuring anti-drug antibodies.

Hypergastrinemia.

Gastrin is an important hormone of the digestive system, which assists gastric acid secretion. It may be pathologically elevated in conditions such as Zollinger-Ellison syndrome, or due to common medications such as proton pump inhibitors. In this review we provide an overview of the pathophysiology and medical causes of hypergastrinemia, diagnostic testing and clinical consequences of chronic hypergastrinemia.

Evolution and comparative genomics of subcellular specializations: EST sequencing of Torpedo electric organ.

Uncharacterized open reading frames (ORFs) in human genomic sequence often show a high degree of evolutionary conservation, yet have little or no tissue EST or protein data suggestive of protein product function. The encoded proteins may have highly restricted expression in specialized cells, subcellular specializations, and/or narrow windows during development. One such highly specialized and minute subcellular compartment is the neuromuscular junction (NMJ), where motorneurons contact muscle fibers. The electric Torpedo ray has evolved to expand the NMJ structure to the size of a large organ (electroplax organ), and we hypothesized that Torpedo electroplax proteins would be candidates for human ESTs expressed at the human NMJ. A total of 9719 primary electroplax cDNA clones were sequenced. We identified 44 human ORFs showing high (>63%) amino acid identity to Torpedo electroplax transcripts with enrichment for mRNA splicing motifs (SH2 and pre-mRNA splicing domains), an observation potentially important for the strict nuclear domains maintained by myonuclei underlying the NMJ. We generated antibodies against two uncharacterized human genes (C19orf29 [Drosophila cactin] and C15orf24) and showed that these were indeed expressed at the murine NMJ. Cactin, a member of the Rel transcription factor family in Drosophila, localized to the postsynaptic cytosol of the NMJ and nuclear membrane. C15orf24 protein localized to the murine postsynaptic sarcolemma. We show a novel approach towards identifying proteins expressed at a subcellular specialization using evolutionary diversity of organ function and cross-species mapping.