A Novel COMP Mutated Allele Identified in a Chinese Family with Pseudoachondroplasia.

Pseudoachondroplasia (PSACH) is an autosomal dominant skeletal dysplasia with an estimated incidence of ~1/60000 that is characterized by disproportionate short stature, brachydactyly, joint laxity, and early-onset osteoarthritis. COMP encodes the cartilage oligomeric matrix protein, which is expressed predominantly in the extracellular matrix (ECM) surrounding the cells that make up cartilage, ligaments, and tendons. Mutations in COMP are known to give rise to PSACH. In this study, we identified a novel nucleotide mutation (NM_000095.2: c.1317C>G, p.D439E) in COMP responsible for PSACH in a Chinese family by employing whole-exome sequencing (WES) and built the structure model of the mutant protein to clarify its pathogenicity. The novel mutation cosegregated with the affected individuals. Our study expands the spectrum of COMP mutations and further provides additional genetic testing information for other PSACH patients.

Regulatory T cells as a new therapeutic target for atherosclerosis.

Atherosclerosis is an autoimmune disease caused by self- and non-self-antigens contributing to excessive activation of T and B cell immune responses. These responses further aggravate vascular infiammation and promote progression of atherosclerosis and vulnerability to plaques via releasing pro-infiammatory cytokines. Regulatory T cells (Tregs) as the major immunoregulatory cells, in particular, induce and maintain immune homeostasis and tolerance by suppressing the immune responses of various cells such as T and B cells, natural killer (NK) cells, monocytes, and dendritic cells (DCs), as well as by secreting inhibitory cytokines interleukin (IL)-10, IL-35 and transcription growth factor ß (TGF-ß) in both physiological and pathological states. Numerous evidence demonstrates that reduced numbers and dysfunction of Treg may be involveved in atherosclerosis pathogenesis. Increasing or restoring the numbers and improving the immunosuppressive capacity of Tregs may serve as a fundamental immunotherapy to treat atherosclerotic cardiovascular diseases. In this article, we briefiy present current knowledge of Treg subsets, summarize the relationship between Tregs and atherosclerosis development, and discuss the possibilities of regulating Tregs for prevention of atherosclerosis pathogenesis and enhancement of plaque stability. Although the exact molecular mechanisms of Treg-mediated protection against atherosclerosis remain to be elucidated, the strategies for targeting the regulation of Tregs may provide specific and significant approaches for the prevention and treatment of atherosclerotic cardiovascular diseases.

Oncogenic induction of cellular high CpG methylation by Epstein-Barr virus in malignant epithelial cells.

Epstein-Barr virus (EBV) is a well-known human herpesvirus associated with virtually all nasopharyngeal carcinoma (NPC) and approximately 10% of gastric cancer (GC) worldwide. Increasing evidence shows that acquired genetic and epigenetic alterations lead to the initiation and progression of NPC and GC. However, even deep whole exome sequencing studies showed a relatively low frequency of gene mutations in NPC and EBV-associated GC (EBVaGC), suggesting a predominant role of epigenetic abnormities, especially promoter CpG methylation, in the pathogenesis of NPC and EBVaGC. High frequencies of promoter methylation of tumor suppressor genes (TSGs) have been frequently reported in NPC and EBVaGC, with several EBV-induced methylated TSGs identified. Further characterization of the epigenomes (genome-wide CpG methylation profile--methylome) of NPC and EBVaGC shows that these EBV-associated tumors display a unique high CpG methylation epigenotype with more extensive gene methylation accumulation, indicating that EBV acts as a direct epigenetic driver for these cancers. Mechanistically, oncogenic modulation of cellular CpG methylation machinery, such as DNA methyltransferases (DNMTs), by EBV-encoded viral proteins accounts for the EBV-induced high CpG methylation epigenotype in NPC and EBVaGC. Thus, uncovering the EBV-associated unique epigenotype of NPC and EBVaGC would provide new insight into the molecular pathogenesis of these unique EBV-associated tumors and further help to develop pharmacologic strategies targeting cellular methylation machinery in these malignancies.

[Immunohistochemical study of tumor necrosis factor-alpha expression in the lungs and small intestines in hyperthermia-LPS co-stressed rats].

OBJECTIVE: To investigate the effects of co-exposure to hyperthermia and lipopolysaccharides (LPS) on tumor necrosis factor-alpha (TNF-alpha) expression in the lungs and small intestines of rats. METHODS: Male pathogen-free Wistar rats were randomly assigned into saline-injected normothermic control (C), saline heat exposure (H), LPS normothermic control (L), and LPS plus heat exposure (HL) groups. The rats in H and HL groups were exposed in a chamber at an ambient dry bulb temperature (Tdb) of 35.0-/+0.5 degrees celsius;, and those in C and L groups to 26-/+0.5 degrees celsius;. In L and HL groups, the rats were given an intravenous injection of LPS 10 mg/kg via the tail vein to induce endotoxemia, and those in C and H group received 10 ml/kg injection. The plasma levels of sTNFrI and sTNFrII were detected at different time points using ELISA. The expression of TNF-alpha in the lungs and small intestines was detected by immunohistochemical SABC method, and the damage of the lungs and small intestines evaluated histologically 120 min after the treatment. RESULTS: Co-exposure to hyperthermia and LPS caused significantly enhanced expressions of TNF-alpha and its receptor sTNFrI and sTNFrII in the plasma and tissues and obvious histopathological damage in the lung and small intestines. CONCLUSION: Co-stress of hyperthermia and LPS-induced toxicity is associated with the expression of TNF-alpha in the lung and small intestines.