Rabbit Anti-Human PTPRE (internal) Polyclonal antibody

Rationale: Congenital heart disease (CHD) is among the most common birth defects. Most cases are of unknown pathogenesis. Objective: To determine the contribution of de novo copy number variants (CNVs) in the pathogenesis of sporadic CHD. Methods and Results: We studied 538 CHD trios using genome-wide dense single nucleotide polymorphism arrays and whole exome sequencing. Results were experimentally validated using digital droplet polymerase chain reaction. We compared validated CNVs in CHD cases with CNVs in 1301 healthy control trios. The 2 complementary high-resolution technologies identified 63 validated de novo CNVs in 51 CHD cases. A significant increase in CNV burden was observed when comparing CHD trios with healthy trios, using either single nucleotide polymorphism array (P=7x10(-5); odds ratio, 4.6) or whole exome sequencing data (P=6x10(-4); odds ratio, 3.5) and remained after removing 16% of de novo CNV loci previously reported as pathogenic (P=0.02; odds ratio, 2.7). We observed recurrent de novo CNVs on 15q11.2 encompassing CYFIP1, NIPA1, and NIPA2 and single de novo CNVs encompassing DUSP1, JUN, JUP, MED15, MED9, PTPRE SREBF1, TOP2A, and ZEB2, genes that interact with established CHD proteins NKX2-5 and GATA4. Integrating de novo variants in whole exome sequencing and CNV data suggests that ETS1 is the pathogenic gene altered by 11q24.2-q25 deletions in Jacobsen syndrome and that CTBP2 is the pathogenic gene in 10q subtelomeric deletions. Conclusions: We demonstrate a significantly increased frequency of rare de novo CNVs in CHD patients compared with healthy controls and suggest several novel genetic loci for CHD.

Modulation of mast-cell activation may provide novel ways to control allergic diseases. Here, we show that protein tyrosine phosphatase epsilon (PTP epsilon; Ptpre) plays key regulatory roles during mast-cell activation mediated by the high-affinity IgE receptor (Fc epsilon RI). Bone marrow-derived mast cells (BMMC) from Ptpre(-/-) mice exhibited enhanced Fc epsilon RI-induced Ca2+ mobilization and mitogen-activated protein kinase (MAPK) (JNK and p38) activation, and showed corresponding enhancement of evoked degranulation and cytokine production, but not leukotriene production. Examination of proteins linking tyrosine kinase activation and Ca2+ mobilization revealed that the absence of PTP epsilon leads to increased phosphorylation of the linker for activation of T cells and SH2 domain-containing leucocyte phosphoproteins of 76 kDa, but not Grb2-associated binder-2 (Gab2). Because Gab2 is considered to be situated downstream of Fyn kinase, we reasoned that Fyn may not be a target of PTP epsilon. In the event, Syk but not Lyn was hyperphosphorylated in PTP epsilon-deficient BMMC. Thus, PTP epsilon most likely exerts its effects at the level of Syk, inhibiting downstream events including phosphorylation of SLP-76 and linker of activated T cells and mobilization of Ca2+. Consistent with the in vitro data, antigen- and IgE-mediated passive systemic anaphylactic reactions were augmented in Ptpre(-/-) mice. Given that the number of mast cells is unchanged in these mice, this observation most likely reflects alterations of mast cell-autonomous signalling events. These data suggest that PTP epsilon negatively regulates Fc epsilon RI-mediated signalling pathways and thus constitutes a novel target for ameliorating allergic conditions.