Expression of β-integrin family members in children with T-cell acute lymphoblastic leukemia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the expression of β-integrin family members in children with T-cell acute lymphoblastic leukemia (T-ALL) and their significance.</p><p><b>METHODS</b>Quantitative real-time PCR analyses were performed to assess the expression levels of β-integrin family members in bone marrow samples from 22 children with newly-diagnosed T-ALL and 21 controls (16 children with non-malignant hematologic disease and 5 healthy donors with bone marrow transplantation). Jurkat cells were treated with integrin inhibitor arginine-glycine-aspartate (Arg-Gly-Asp, RGD) peptide. The cell viability and apoptosis rate were determined by CCK8 assay and flow cytometry respectively.</p><p><b>RESULTS</b>The mRNA levels of integrins β, β, and βwere significantly lower in children with T-ALL than in controls (P<0.05). In T-ALL patients, high integrin βexpression was associated with lower white blood cell counts (<100×10/L), minimal residual disease (MRD) positivity, and day 33 bone marrow negative remission (P<0.05). In T-ALL patients, higher integrin βexpression was associated with relapse of T-ALL (P<0.05). Based on survival curve analysis, higher integrin βexpression was related to lower event-free survival and overall survival rates. RGD peptide treatment inhibited the proliferation of Jurkat cells and increased their apoptosis rate (P<0.05).</p><p><b>CONCLUSIONS</b>β-Integrin may play a role in the occurrence and development of T-ALL by affecting cell proliferation and apoptosis. The expression of integrin β5 is closely related to the risk of relapse of T-ALL. The expression of integrin β3 is closely related the treatment response and prognosis of T-ALL.</p>

Integrin-ß1, not integrin-ß5, mediates osteoblastic differentiation and ECM formation promoted by mechanical tensile strain

BACKGROUND: Mechanical strain plays a great role in growth and differentiation of osteoblast. A previous study indicated that integrin-ß (ß1, ß5) mediated osteoblast proliferation promoted by mechanical tensile strain. However, the involvement of integrin-ß; in osteoblastic differentiation and extracellular matrix (ECM) formation induced by mechanical tensile strain, remains unclear. RESULTS: After transfection with integrin-ß1 siRNA or integrin-ß5 siRNA, mouse MC3T3-E1 preosteoblasts were cultured in cell culture dishes and stimulated with mechanical tensile strain of 2500 microstrain (µÎµ) at 0.5 Hz applied once a day for 1 h over 3 or 5 consecutive days. The cyclic tensile strain promoted osteoblastic differentiation of MC3T3-E1 cells. Transfection with integrin-ß1 siRNA attenuated the osteoblastic diffenentiation induced by the tensile strain. By contrast, transfection with integrin-ß5 siRNA had little effect on the osteoblastic differentiation induced by thestrain. At thesametime, theresultofECM formation promoted by the strain, was similar to the osteoblastic differentiation. CONCLUSION: Integrin-ß1 mediates osteoblast differentiation and osteoblastic ECM formation promoted by cyclic tensile strain, and integrin-ß5 is not involved in the osteoblasts response to the tensile strain.

Effect of integrin β8 on TGF-β1 activation in astrocytes with oxygen glucose deprivation / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the effect of β8 expression on transforming growth factor β1(TGF-β1) activation in astrocytes with oxygen glucose deprivation (OGD).</p><p><b>METHODS</b>Astrocytes were cultured and then subjected to OGD to generate hypoxia-ischemia (HI) model in vitro. Immunocytochemistry was used to detect the expression and distribution of β8 in nomoxia cultured cells. β8 protein expression was quantified by Western blot at 12 hours, 1 day and 2 days after OGD. Astrocytes and luciferase reporter cells (TMLC) were co-cultured. β8 RNA interference system was established to specifically inhibit β8 expression in cultured astrocytes. TGF-β1 activation was then detected in the co-culture system.</p><p><b>RESULTS</b>β8 was mainly located in the cytoplasm and neurites of astrocytes. OGD resulted in increase of β8 protein expression at 12 hours after reoxygenation in astrocytes, which was peaked at 1 day after reoxygenation. TGF-β1 activation was in accordance with β8 expression in astrocyte-TMLC co-culture system after reoxygenation. After the inhibition of β8, TGF-β1 activation was significantly reduced in all time points.</p><p><b>CONCLUSIONS</b>The highly expressed β8 plays important roles in the regulation of TGF-β1 activation in neonatal rats with hypoxic-ischemic brain damage.</p>

Inhibition of Transfer Infection of Epstein-Barr Virus to Epithelial Cells by Integrin beta6 siRNA

Epstein-Barr virus (EBV) establishes a latent infection in greater than 90% of the world's adult population and associates with various tumors. EBV primarily infects epithelial cells and B cell in vivo. Mechanism of EBV infection in B cells is known to involve binding of EBV glycoprotein gp350 to CD21 on B cell surface. Epithelial cells are infected with EBV even though most of epithelial cells do not express CD21. Recently, integrin alphavbeta5, alphavbeta6 and alphavbeta8 on epithelial cells were reported to facilitate EBV infection by interacting with gHgL complex. We examined the expression profile of integrins known to be expressed on epithelial cells. Integrin alphavbeta5 and alphavbeta6, but not alphavbeta8 were detected in a gastric epithelial cell line, AGS. We then tested whether siRNAs specific to beta6 can inhibit EBV infection of epithelial cells. One among the four tested siRNAs significantly reduced beta6 expression and suppressed transfer infection of EBV to AGS cells. Our data suggest that siRNAs to integrins might be useful to control EBV infection to epithelial cells.

correlation between the endometrial integrins and osteopontin expression with pinopodes development in ovariectomized mice in response to exogenous steroids hormones

The ovariectomized animals are good models to evaluate the effect of different steroid hormone treatments on implantation events and the pattern of integrin expression. Therefore, this study was performed to compare the expression of integrins and osteopontin [OPN] in correlation with pinopode development in ovariectomized mice endometrium which was subjected to steroid hormones. Ovariectomized mice were subjected to estrogen, progesterone and estrogen-progesterone hormones. Their uterine horns were evaluated for integrin expression by immunohistochemistry and real-time RT-PCR and for pinopode development by transmission and scanning electron microscopic studies. No immunostaining for integrin and OPN molecules were detected in the endometrium of non-ovariectomized mice except in metestrus phase. The alpha4 and beta 1 integrin genes were expressed in all phases of estrous cycle. In ovariectomized mice, no reaction was detected in the endometrium of control, sham and estrogen-treated groups, but in both progesterone-treated groups, all examined genes were expressed. There was not any correlation between pinopodes and integrin expression in ovariectomized mice. The progesterone is more effective on endometrial integrin expression than estrogen and differences in the expression pattern of integrins reflect their important and different roles in embryo implantation. The pinopodes may have minor effect in mice implantation or have some delay in their expressions in ovariectomized mice which were subjected to exogenous hormones

Expression and significance of integrins subunits in laryngeal squamous cell carcinoma / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#This study was to investigate the expression and significance of Integrins subunits in laryngeal squamous cell carcinoma (LSCC).@*METHOD@#The expression of Integrins subunits was detected by cDNA microarray in 4 cases of primary LSCC tissues and corresponding adjacent normal tissues. Semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) were used to identify the different expression of Integrins subunits in 24 cases of primary LSCC tissues and corresponding adjacent normal tissues.@*RESULT@#A cDNA microarray analysis revealed significant changes in the expression of Integrins subunits, with IntegrinalphaV, Integrinbeta8 being up-regulated and Integrinalpha8 being down-regulated. The result of RT-PCR was consistent with that of cDNA microarray. The mRNA levels of IntegrinalphaV and Integrinbeta8 were significantly higher in LSCC tissues than that in corresponding adjacent normal tissues (1.0131 +/- 0.4780 vs 0.7591 +/- 0.4678 for IntegrinalphaV, P<0.05, 1.7362 +/- 1.3849 vs 1.2267 +/- 0.9363 for Integrinbeta8, P<0.05). The mRNA levels of Integrinalpha8 were significantly lower in LSCC tissues than that in corresponding adjacent normal tissues (0.2646 +/- 0.2622 vs 0.5457 +/- 0.3827, P<0.05).@*CONCLUSION@#The expression of IntegrinalphaV, Integrinbeta8, Integrinalpha8 were significantly up-regulated or down-regulated in laryngeal squamous cell carcinoma, which may relate to tumorigenesis and development of laryngeal squamous cell carcinoma.

[Leukocyte adhesion deficiency]

Leukocyte adhesion deficiency [LAD] is a rare functional leukocyte disorder, which is divided into two separate types: LAD-1 and LAD-2. LAD-1 results from lack of beta2 integrin molecules [CD 11 and CD 18] on the leukocyte cell surface. These molecules are essential for leukocyte adhesion to endothelial cells and chemotaxis. The present case report is about a 42-month-old girl with recurrent otitis, pneumonia and gingivitis. On physical examination, patient was pale and malnourished. Multiple desquamated erythematous plagues were found on her body and extremities. Blood investigations revealed persistent leukocytosis with normal serum Immunoglobulin profile and complement. The diagnosis of LAD1 was made based on Flow cytometry finding; showing decreased in GD11 and CD 18 markers of PMN-a. When a patient has persistent leukocytosis and recurrent infections, investigation for the primary immune deficiency, specially leukocyte adhesion deficiency must be considered

[ changes of alpha v, beta 3, alpha 4, beta 1 integrins expression and osteopontin their ligands in murine estrous cycle]

Considering the importance of integrin molecules in the implantation and lack of sufficient information in the expression pattern of these molecules in various phases of estrous cycle. It seemed to be necessary to investigate these molecules in mouse endometrial during the various phases of oestrous cycle. Female NMRI mice [n=15] aged 6-8 weeks were studied. Various phases of estrous cycle including: proestrus, estrus, metestrus and diestrus were determined by vaginal smear. The mice were sacrificed [at least 3 per each phase] by cervical dislocation and the tissues were obtained from the middle 1/3 part of their uterine horns at each phase then the cryosections at thicknesses between 8-10 micro were obtained. Then the immunohistochemistry were done for integrins of alpha4, beta1, alphav, beta3 and their ligand osteopontine. The integrins were expressed only in the metestrous phase of oestrous cycle in the different locations of mouse endometrium. The positive reactions were observed for alphav, alpha4 and beta3 in the apical and basal membrane of glandular epithelium. Also the positive reaction for beta1 was found in surface and glandular epithelium as well as stroma. The osteopontin expression was seen in the apical membranes of surface and glandular epithelium and was not seen in other locations. It seems that expression of integrins in endometrium is based on their role in the implantation, therefore the molecules alpha4, beta1 and OPN that are expressed on the surface epithelial may be involve in the adhesion of cell to cell and integrins of alphav, beta3 that are expressed in the glandular

Study on the overlapping growth of hepatoma cells in vitro / 生物医学工程学杂志

This study inquired into the formation of the "overlapping growth" of hepatoma cells through quantitative characterization on the growth of hepatoma cells in situ by means of morphological observation, Image Tool computer analytic system, statistical analysis as well as the experimental methods of cell mechanics and biochemistry. The results were as follows: (1) The ability of hepatoma cells to regulate cell morphological deformation was better than that of hepatic cells; (2) While we were using micropipette aspiration technique to suck the "overlapping growth plaque" of hepatoma cells, the "overlapping growth plaque" fell off from the substrate, leaving a blank area; (3) Integrin expression of hepatoma cells was more obvious than that of hepatic cells; (4) Fibronectin (Fn) down-regulated the integrin expression in the hepatoma cells cultured on the Fn coated surface, enhanced the cells' adhesion ability and morphological stability, but reduced the formation and aggregation of the round cells. These results indicated (1) The so-called overlapping growing area was actually formed by many closely arrayed and piled round cells; (2) The production of round cells may be caused by integrin abnormal expression and the effect on the hepatoma cells adhesion stability; (3) The formation of "overlapping growth plaque" in hepatoma cells is related to the round cells' congregation induced by the high frequency morphological transformation.

Molecular cloning and characteristics of cDNA encoding pig beta6 subunit for FMDV receptor / 生物工程学报

In order to study the roles of integrin beta6 in Foot-and-Mouth Disease Virus infection, pig integrin beta6 was firstly molecularly cloned from RNA of the tongue and lung of recovered pig infected experimentally with foot-and-mouth-disease virus (FMDV), and was compared with the beta6 gene of other animals available in GenBank at nucleotide and amino acid leves. GeneBank association number of the beta6 gene is EF432729. Pig integrin beta6 gene (2367bp) encodes a polypeptide of 788 amino acids consisting of 9 potential N-linked glycosylation sites, 3 Glycosaminoglycan attachment sites, a cGMP-dependent protein kinase phosphorylation site, 10 Protein kinase C phosphorylation sites, 2 EGF-like domains and 2 cysteine-rich regions. Pig integrin beta6 subunit has a 26-residue putative signal peptide, a 681-residue ectodomain, a 29-residue transmembrane domain, and a 52-residue cytoplasmic domain. 11 mutant nucleotides were found in beta6 gene coding region and 9 amino acids were changed. The nucleotide sequence similarity of integrin beta6 gene between rheses monkey, mouse, Norway rat, dog, guinea pig, human, bovine, sheep is 79.5%, 84.9%, 85.4%, 85.2%, 88.7%, 90.1%, 91.9% and 91.9%, and the amino acid sequence similarity is 93.5%, 88.2%, 88.5%, 88.3%, 91.0%, 92.8%, 93.3% and 93.4% respectively. This study will lay a foundation for understanding the interactions of FMDV with receptors.

Adesão de fagócitos monucleares ao conjuntivo na leishmaniose: papel de integrinas Beta sub 1, e receptores de quimiocinas / Monocuclear phagocyte-connective tissue adhesion in leishmaniasis: role of Beta sub 1-integrin and chemokine receptors

Parasitos do gênero Leishmania podem causar lesões na pele, mucosas ou vísceras. Os mecanismos que regulam o tropismo do parasito não estão bem esclarecidos, mas moléculas na superfície de fagócitos infectados podem ter um papel importante. Nosso grupo demonstrou anteriormente que a infecção por Leishmania reduz a adesão de fagócitos mononucleares ao tecido conjuntivo inflamado. Uma vez que a perda de adesão ao tecido conjuntivo é o primeiro passo para a migração celular, este fenômeno pode estar relacionado com a habilidade destas células em deixar o tecido inflamado em direção ao linfonodo drenante. Nesta dissertação, nós examinamos o papel de moléculas de adesão e de receptores de quimiocinas na perda de adesão de fagócitos mononucleares ao tecido conjuntivo inflamado. Para isso nós empregamos análises de citometria de fluxo de moléculas de adesão em fagócitos infectados com Leishmania marcada com fluorocromo. Além disso, realizamos ensaios de adesão celular e análise de expressão de RNAm para receptores de quimiocinas através de RT-PCR em tempo real. Nós observamos que a porcentagem de células infectadas (r=-0,826; P=0,003) e o número de parasitos por célula infectada (r=-0,917; P=0,028) se correlacionaram negativamente com a adesão ao tecido conjuntivo. A redução na adesão celular induzida pela infecção por Leishmania (58,7 à 75,0%; P=0,005) ocorreu tão cedo quanto duas horas após a infecção e foi mantida por pelo menos 24 horas. A infecção com apenas 0,6 parasito por célula reduziu a adesão em 27,9 a 44,6% (P<0,00l). O bloqueio na adesão celular foi mantido pela infecção por Leishmania, mas pela fagocitose de parasitos mortos (adesão celular variou de 15,2% abaixo a 24.0% acima do controle; P>0,05). A infecção por Leishmania também reduziu a adesão celular a fibronectina (54,1 a 96,2%, P<0,0l), colágeno (15,7 à 83,7%, P<0,05) ou laminina (59,1 à 82,2%, P<0,05). Não houve modulação da expressão de VLA4, VLA5, LFA-1, Mac-1, L-Selectina,...

Expressão imuno-histoquímica das integrinas a2B1, a3B1 e a5B1 em folículos pericoronários espessados e cistos dentígeros incipientes / Imuno-histoquímica expression of the integrinas a2B1, a3B1 and a5B1 in espessados pericoronários folículos and incipient dentigerous cysts

Uma das grandes controvérsias encontradas na literatura científica consiste no estabelecimento de critérios para distinção entre um folículo pericoronário espessado e um cisto dentígero incipiente. O objetivo do presente estudo consistiu em avaliar a expressãoimuno-histoquímica das integrinas

Molecular mechanism of the sensitivity of myocardial cell injury after severe hypoxia / 中华烧伤杂志

<p><b>OBJECTIVE</b>To explore the molecular mechanism of the sensitivity of myocardial cell injury after severe hypoxia.</p><p><b>METHODS</b>Differential expression of the genes in rat myocardium and skeletal muscles after severe hypoxia for 6 hours was determined by DNA chip containing 4096 mice genes.</p><p><b>RESULTS</b>There were high expressions of 125 genes in skeletal muscles and 111 genes in myocardial cells after 6 hours of severe hypoxia. Among them, high expression genes in myocardial cells included those encoding apoptosis activator Mtd, complement C3, vascular cell adhesion molecule-1, integrin beta subunit and lipopolysaccharide binding proteins (LBP).</p><p><b>CONCLUSION</b>Activation of apoptosis of myocardial cells and inflammatory mediators played important roles in myocardial cell injury after 6-hour severe hypoxia.</p>