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Liu J.,Jishuitan Hospital | Xia M.,Peking University | Wang P.,Key Laboratory of Medical Immunology | Wang C.,Peking University | And 5 more authors.
Gene | Year: 2016

Recently, immunoglobulin (Ig) expression was reported in a variety of non-B lineage cells, including myeloid cells. We assessed whether hematopoietic stem/progenitor cells (HSC/HPCs) can express Ig. With Gene Expression Omnibus (GEO) microarray database analysis, we found that IGHM was expressed with the highest frequency and level in umbilical cord blood CD34+ HSC/HPCs, followed by IGK at, IGHE, IGHD, IGHG1, and IGHA1, while IGL at was nearly not expressed. Ig expression was further confirmed by molecular experiments and immunofluorescence. Moreover, HSC/HPCs-derived Ig displayed restricted/biased usages and VHDJH rearrangement patterns. These results suggest that Igs, especially IgM, may have a role in CD34+ HSC/HPCs function. © 2015 Elsevier B.V..

Jiang D.,Peking University | Jiang D.,Key Laboratory of Medical Immunology | Ge J.,Peking University | Liao Q.,Peking University | And 10 more authors.
International Journal of Molecular Sciences | Year: 2015

The innate immune system of the skin is thought to depend largely on a multi-layered mechanical barrier supplemented by epidermis-derived antimicrobial peptides. To date, there are no reports of antimicrobial antibody secretion by the epidermis. In this study, we report the expression of functional immunoglobulin G (IgG) and immunoglobulin A (IgA), previously thought to be only produced by B cells, in normal human epidermal cells and the human keratinocyte line HaCaT. While B cells express a fully diverse Ig, epidermal cell-expressed IgG or IgA showed one or two conservative VHDJH rearrangements in each individual. These unique VDJ rearrangements in epidermal cells were found neither in the B cell-derived Ig VDJ databases published by others nor in our positive controls. IgG and IgA from epidermal cells of the same individual had different VDJ rearrangement patterns. IgG was found primarily in prickle cells, and IgA was mainly detected in basal cells. Both epidermal cell-derived IgG and IgA showed potential antibody activity by binding pathogens like Staphylococcus aureus, the most common pathogenic skin bacteria, but the microbial-binding profile was different. Our data indicates that normal human epidermal cells spontaneously express IgG and IgA, and we speculate that these Igs participate in skin innate immunity. © 2015 by the authors; licensee MDPI, Basel, Switzerland.

Xu D.,Key Laboratory of Medical Immunology | Xu D.,Peking University | Yang F.,Peking University | He H.,Peking University | And 7 more authors.
Applied Immunohistochemistry and Molecular Morphology | Year: 2013

Transmembrane protein 166 (TMEM166) is a novel human regulator involved in both autophagy and apoptosis. In this study, we generated a specific rabbit polyclonal antibody against human TMEM166 and assessed the expression of this protein in various human normal and tumor tissue samples by tissue microarray-based immunohistochemical analysis. Varying TMEM166 protein levels were expressed in a cell-type and tissue- Type-specific manner in detected tissues or organs. Strong TMEM166 expression was shown in the glomerular zona of the adrenal cortex, chromophil cells of the pituitary gland, islet cells, squamous epithelium of the esophagus mucosa, the fundic gland, and hepatocytes. Moderate or weak TMEM166 staining was identified in the parathyroid gland, the testis, vaginal stratified squamous cells, lung macrophages, hematopoietic cells, renal tubular epithelial cells, macrophages in the spleen red pulp, and neuronal cells in the cerebral cortex. Some tissues failed to stain for TMEM166, such as adipose tissue, colon, cerebellum, lymph node, mammary gland, ovary, prostate, rectum, skin, small intestine, thyroid gland, tonsil, and thymus. In comparing human normal and tumor tissues, TMEM166 expression was widely downregulated in the cancer tissues. Our studies provide the basis for future investigations into cell-type- specific functions of this protein in human normal and tumor tissues.©2013 by Lippincott Williams& Wilkins.

Gong H.,Jilin University | Gong H.,Beijing Institute of Pharmacology and Toxicology | Qi H.,Key Laboratory of Medical Immunology | Sun W.,Jilin University | And 6 more authors.
Molecules | Year: 2012

A series of pyrido[2,3-d]pyrimidine derivatives were designed and synthesized based on known CC chemokine receptor 4 (CCR4) antagonists. The activities of all the newly synthesized compounds were evaluated using a chemotaxis inhibition assay. Compound 6b was proven to be a potent CCR4 antagonist that can block cell chemotaxis induced by macrophage-derived chemokine (MDC), thymus and activation regulated chemokine (TARC), and CKLF1, the natural ligands of CCR4. In addition, compound 6b is more effective than budesonide in the murine rhinitis model. The intravenous injection LD 50 of compound 6b is 175 mg/kg and the oral LD 50 is greater than 2,000 mg/kg.

Su Y.,Peking University | Su Y.,Key Laboratory of Medical Immunology | Lin Y.,Peking University | Lin Y.,Capital Medical University | And 28 more authors.
Cancer Science | Year: 2014

The CKLF-like MARVEL transmembrane domain containing 3 (CMTM3) gene is a novel tumor suppressor with frequent epigenetic inactivation. In this study, we showed the role played by CMTM3 in gastric cancer cells as a tumor suppressor gene, and examined the correlation between CMTM3 expression and clinicopathological parameters using immunohistochemistry in gastric cancer patients with different pathological stages (n = 350). We found that CMTM3 expression was reduced or silenced by epigenetic regulation in gastric cell lines, and dramatically downregulated in primary gastric cancer tissues. Restoration of CMTM3 significantly affected migration and invasion of AGS and SGC-7901 cells (P < 0.001). In vivo experiments showed that peritoneal disseminated metastases were significantly suppressed by CMTM3 (P < 0.001). We further showed that the expression of MMP2 and the phosphorylation of Erk1/2 were decreased when CMTM3 was restored. In addition, by immunohistochemical staining, we found that the expression of CMTM3 was remarkably weaker in gastric cancer tissues than in normal mucosae (P = 0.008), and was significantly correlated with gender (P = 0.033), tumor depth (P = 0.049), stage (P = 0.021), and histological grade (P = 0.022). More importantly, CMTM3 expression was associated with prognosis in gastric cancer patients (P = 0.041), and was a significant independent prognostic indicator (hazard ratio = 0.704, 95% confidence interval, 0.498-0.994; P = 0.046). Our findings indicate that CMTM3 regulates migration and invasion of gastric cancer cells. Moreover, CMTM3 is a candidate marker for prognosis of gastric cancer in the clinic. © 2013 The Authors.

Shao W.,Peking University | Hu F.,Peking University | Ma J.,Key Laboratory of Medical Immunology | Zhang C.,Peking University | And 5 more authors.
International Journal of Biochemistry and Cell Biology | Year: 2016

Currently, natural IgM antibodies are considered to be the constitutively secreted products of B-1 cells in mice and humans. In this study, we found that mouse epithelial cells, including liver epithelial cells and small intestinal epithelial cells (IECs), could express IgM that also showed natural antibody activity. Moreover, similar to the B-1 cell-derived natural IgM that can be upregulated by TLR9 agonists (mimicking bacterial infection), the expression of epithelial cell-derived natural IgM could also be significantly increased by TLR9 signaling. More importantly, the epithelial cell-derived IgM was polyreactive, and it could recognize single-stranded DNA (ssDNA), double-stranded DNA (dsDNA), lipopolysaccharide (LPS), and insulin with low affinity; additionally, TLR9 agonists could enhance it in a MyD88-dependent manner. Furthermore, epithelial cell-derived IgM could bind various bacteria; therefore, it could be involved in anti-infection responses. Together, these results highlight the fact that epithelial cells are an important source of natural IgM, in addition to that produced by B-1 cells, and IgM contributes to the innate immune responses in local tissues, further demonstrating that the epithelium is a first line of defense in the protection against invading microbes. © 2016 Elsevier Ltd. All rights reserved.

Li T.,Peking University | Li T.,Key Laboratory of Medical Immunology | Guo X.,Peking University | Guo X.,Key Laboratory of Medical Immunology | And 7 more authors.
Molecular Medicine Reports | Year: 2015

Numerous leukocyte differentiation antigens act as important markers for research, diagnosis, triage and eventually treatment targets for hematopoietic malignancies. Vset and transmembrane domaincontaining 1 (VSTM1) was identified by immunogenomic analysis as a potential leukocyte differentiation antigen gene. VSTM1 is located at 19q13.4 on human chromosomes, an important genomic region prone to genetic and epigenetic modifications in numerous hematopoietic malignancies. VSTM1v1, a primary splicing form encoded by VSTM1, is a type I transmembrane molecule with an extracellular immunoglobulin Vlike domain and two cytoplasmic immunoreceptor tyrosine-based inhibitory motifs. In the present study, VSTM1 expression was examined in normal human peripheral leukocytes and hematopoietic tumor cell lines; in addition, the aberrant methylation of the VSTM1 gene was evaluated using methylationspecific polymerase chain reaction (MSP). The results of the present study demonstrated that VSTM1 was widely expressed in normal human peripheral blood leukocytes, including granulocytes and monocytes, in concurrence with previous studies, as well as lymphocytes; in addition, the molecular size and expression levels of VSTM1 varied considerably between leukocytes. However, VSTM1 was undetectable in numerous hematopoietic tumor cell lines following promoter hypermethylation. The effects of pharmacologicallyinduced demethylation of the VSTM1 gene and promoter region were analyzed using MSP and biosulfite genomic sequencing, and the results revealed that VSTM1 expression was restored in methylationsilenced Jurkat cells. In addition, CKK8 assays revealed that VSTM1v1 overexpression in Jurkat cells resulted in growth suppression. Furthermore, the inhibitory effect on cell growth was enhanced following antibodyinduced crosslinking of VSTM1v1. In conclusion, the results of the present study indicated that promoter methylation silenced VSTM1 and negatively regulated cell growth in human hematopoietic malignancy cell lines.

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