Rabbit Anti-Human ITGA1 Polyclonal antibody

The purpose of this study was to identify the differences in angiogenesis gene expression between normal and diabetic keratocytes stimulated with interleukin-1 alpha (IL-1 alpha) and tumor necrosis factor-alpha (TNF-alpha). Primarily cultured normal and diabetic keratocytes were treated with 20 ng/mL of IL-1 alpha and TNF-alpha for 6 hr. cDNA was hybridized to an oligonucleotide microarray. Microarray analysis was used to identify differentially expressed genes that were further evaluated by real-time polymerase chain reaction (RT-PCR). Diabetes keratocytes overexpressed vital components of angiogenesis including Agtr1, and under-expressed components related to the blood vessel maturation, including Dcn. Cytokine-treated diabetic keratocytes differentially expressed components of angiogenesis. OLETF keratocytes after treatment with IL-1 alpha and TNF-alpha showed the newly expressed 15 and 14 genes, respectively. Newly and commonly under-expressed five genes followed by treatment with both IL-1 alpha and TNF-alpha were also evident. RT-PCR showed results similar to the microarray results. Agtr1 and Itga1 showed an increased expression in diabetic keratocytes compared with normal corneal keratocytes, especially after TNF-alpha treatment. Il6 appeared strong expression after interleukin-1 alpha treatment, but showed down expression after TNF-alpha treatment. Further studies to analyze and confirm the significance of the identified angiogenetic genes of diabetes are needed.

The integrin collagen receptor locus on human chromosome 5qll.2 includes the integrin genes ITGA1 and ITGA2 and the cell cycle regulation gene PELO, embedded within ITGA1 intron 1. ITGA1 contains a CArG box that is bound by serum response factor (SPF), while PELO contains two Sp1 binding elements. A comparison of mRNA levels in megakaryocytic (MK) and non-megakaryocytic (non-MK) cell lines and an analysis of the transcriptional activity of promoter-LUC reporter gene constructs in transfected cells revealed that ITGA1 is selectively suppressed in the MK lineage. Sodium bisulfite genomic sequencing established that a CpG-rich ITGA1 promoter region (-209/+115) is fully methylated at 19 CpG sites in MK cells that do not express alpha 1 beta 1, but completely demethylated in expressing cells. In vitro methylation of ITGA1 suppresses transcription; while treatment of megakaryocytic cells with 5-aza-2'-deoxycytidine, but not Trichostatin A, resulted in de novo expression of ITGA1. During thrombopoietin-induced in vitro differentiation of primary human cord blood mononuclear cells into megakaryocytes, we observed rapid, progressive CpG methylation of ITGA1, but not PELO or ITGA2. Thus, selective CpG methylation of the ITGA1 promoter is a specific feature of alpha 1 beta 1 regulation that coincides with the initiation of megakaryocyte differentiation. (c) 2007 Elsevier B.V. All rights reserved.