Biomedical subjects

Xiao Yang

Publications and source records attributed to Xiao Yang.

At least 37 records · Page 2Linked to original sources

PubMed2005

Smad4 is required for the normal organization of the cartilage growth plate.

Smad4 is the central intracellular mediator of transforming growth factor-beta (TGF-beta) signals. To study the role of Smad4 in skeletal development, we introduced a conditional mutation of the gene in chondrocytes using Cre--loxP system. We showed that Smad4 was expressed strongly in prehypertrophic and hypertrophic chondrocytes. The abrogation of Smad4 in chondrocytes resulted in dwarfism with a severely disorganized growth plate characterized by expanded resting zone of chondrocytes, reduced chondrocyte proliferation, accelerated hypertrophic differentiation, increased apoptosis and ectopic bone collars in perichondrium. Meanwhile, Smad4 mutant mice exhibited decreased expression of molecules in Indian hedgehog/parathyroid hormone-related protein (Ihh/PTHrP) signaling. The cultured mutant metatarsal bones failed to response to TGF-beta1, while the hypertrophic differentiation was largely inhibited by Sonic hedgehog (Shh). This indicated that Ihh/PTHrP inhibited the hypertrophic differentiation of chondrocytes independent of the Smad4-mediated TGF-beta signals. All these data provided the first genetic evidence demonstrating that Smad4-mediated TGF-beta signals inhibit the chondrocyte hypertrophic differentiation, and are required for maintaining the normal organization of chondrocytes in the growth plate.

Animals↗

PubMed2005

Disruption of Smad5 gene induces mitochondria-dependent apoptosis in cardiomyocytes.

Our previous studies have shown that SMAD5, an important intracellular mediator of transforming growth factor beta (TGF-beta) family, is required for normal development of the cardiovascular system in vivo. In the current study, we reported that the lack of the Smad5 gene resulted in apoptosis of cardiac myocytes in vivo. To further investigate the mechanism of the Smad5 gene in cardiomyocyte apoptosis, the embryonic stem (ES) cell differentiation system was employed. We found that the myotubes that differentiated from the homozygous Smad5ex6/ex6 mutant ES cells underwent collapse and degeneration during the late stages of in vitro differentiation, mimicking the in vivo observation. By electron microscopy, abnormal swollen mitochondria were observed in cardiomyocytes both from Smad5-deficient embryos and from ES-differentiated cells. There was also a significant reduction in mitochondrial membrane potential (Deltapsi m) and a leakage of cytochrome c from mitochondria into the cytosol of myocytes differentiated from Smad5 mutant ES cells. The expression of p53 and p21 was found to be elevated in the differentiated Smad5 mutant myocytes, and this was accompanied by an up-regulation in caspase 3 expression. These results suggest that the Smad5-mediated TGF-beta signals may protect cardiomyocytes from apoptosis by maintaining the integrity of the mitochondria, probably through suppression of p53 mediated pathways.

Animals↗

PubMed2005

Transgenic mice that express Cre recombinase in hypertrophic chondrocytes.

In order to investigate the physiological control of hypertrophic chondrocytes which present the terminally differentiated form of chondrocytes, we generated a mouse line expressing the Cre recombinase under the control of the mouse type X collagen (Col10a1) promoter. In situ hybridization analysis demonstrated the expression of Col10a1-Cre transgene in hypertrophic chondrocytes of femur at postnatal day 2 (P2). In order to test the excision activity of the Cre recombinase, the Col10a1-Cre transgenic line was crossed with the mouse strain carrying the Smad4 conditional alleles (Smad4co/co) and the reporter line ROSA26. Multiple tissue PCR of Col10a1-Cre;Smad4co/+ mice revealed the restricted Cre activity in tissues containing hypertrophic chondrocytes. LacZ staining revealed that the Cre activity was observed in the cartilage primordia of ribs at E14.5 and only detected in the lower hypertrophic region of ribs at P1. These data suggest that the Col10a1-Cre mouse line described here could be used to achieve conditional gene targeting in hypertrophic chondrocytes.

Animals↗

PubMed2005

Expression of connective tissue growth factor in renal tubulointerstitial fibrosis in rats and its pathogenic role.

In order to explore the role of connective tissue growth factor (CTGF) in the pathogenesis of renal tubulointerstitial fibrosis, 48 Wistar rats were randomly divided into sham-operated and unilateral ureteral obstruction (UUO) group. On the postoperative day 1, 3, 7 and 14, the rats were killed and the kidneys were removed. The renal tubulointerstitial injury index was evaluated according to the MASSON staining. The mRNA levels of CTGF, transforming growth factor-beta1 (TGF-beta1), collagen I (col I), and plasminogen activator inhibitor-1 (PAI-1) were detected using reverse transcriptional-polymerase chain reaction (RT-PCR). Immunohistochemistry was performed to evaluate the protein expression of the above factors, and the relations among them were analyzed. Quantitative expression of CTGF protein in the kidneys was also assessed using Western blot. The results showed that TGF-beta1 mRNA level was increased at first day after UUO, followed by a marked elevation of CTGF mRNA level, which began to increase 3 days after UUO (P < 0.01). With the progression of the disease, the mRNA expression of CTGF, col I and PAI-1 was increased progressively. Immunohistochemistry revealed that the CTGF protein expression was significantly increased in fibrotic areas and tubular epithelial cells 3 days after UUO. On the post-UUO day 7, the protein level of CTGF was positively related to the renal tubulointerstitial injury index (r = 0.62, P < 0.01), the expression of TGF-beta1 (r = 0.85, P < 0.01), col I (r = 0.78, P < 0.01), and PAI-1 (r = 0.76, P < 0.01). Upon Western blot analysis, CTGF protein expression began to increase 3 days after UUO, and appeared progressively throughout the time course (P < 0.01, as compared with sham-operated group). It is concluded that CTGF can be induced by TGF-beta and mediate various profibrotic actions of this cytokine, such as increasing extracellular matrix (ECM) synthesis and decreasing ECM degradation. The increased expression of CTGF may play a crucial role in the development and progression of tubulointerstitial fibrosis.

Animals↗

PubMed2005

Human pescadillo induces large-scale chromatin unfolding.

The human pescadillo gene encodes a protein with a BRCT domain. Pescadillo plays an important role in DNA synthesis, cell proliferation and transformation. Since BRCT domains have been shown to induce chromatin large-scale unfolding, we tested the role of Pescadillo in regulation of large-scale chromatin unfolding. To this end, we isolated the coding region of Pescadillo from human mammary MCF10A cells. Compared with the reported sequence, the isolated Pescadillo contains in-frame deletion from amino acid 580 to 582. Targeting the Pescadillo to an amplified, lac operator-containing chromosome region in the mammalian genome results in large-scale chromatin decondensation. This unfolding activity maps to the BRCT domain of Pescadillo. These data provide a new clue to understanding the vital role of Pescadillo.

Amino Acid Sequence↗

PubMed2005

[SMAD3 inhibits the expression of MMP-2 in mouse embryonic fibroblasts].

SMAD3 is one of the receptor-activated SMADs which are important in TGF-beta signal transduction. Smad3-null mice show accelerated cutaneous wound healing compared with wild-type mice. In this work, we investigated the functions and the mechanism of Smad3-mediated TGF-beta signal on matrix metaloproteinase-2 (MMP-2) in mouse fibroblast. We found that MMP-2 at wound bed was expressed earlier in Smad3-null mice than that in wild type and heterozygotes. In the sera of wounding mice, the activity of MMP-2 was also remarkably higher in Smad3-null mice than that in the other two. The embryonic fibroblasts were separated from Smad3 knockout mice to test the function of Smad3 in modulating the expression of MMP-2. The results showed that the expression and activity of MMP-2 in Smad3-null fibroblasts were higher than those in wild type cells. TGF-beta1 could increase the MMP-2 activities in both Smad3 mutant and wild type fibroblasts. The expression and activity of MMP-2 were inhibited by over expression of SMAD3 in Smad3-null fibroblasts, while the expression and activity of MMP-2 were increased by over expression of anti-sense Smad3 in wild type cells. All these results showed that SMAD3 inhibited the expression of MMP-2 in mouse embryonic fibroblasts.

Animals↗

PubMed2005

Endothelial cell-specific expression of Cre recombinase in transgenic mice.

Endothelial cells participate in angiogenesis, vascular homeostasis, thrombosis, inflammation and vascular wall remodeling. To study the function of genes in endothelial cells using Cre-loxP system, we generated Tie2-Cre transgenic mice, in which expression of Cre recombinase is driven by Tie2 promoter. Total six founder mice carrying the Tie2-Cre transgene were identified by genomic PCR and Southern blot. The integration efficiency is 11%. In order to test the excision activity and tissue distribution of the Cre recombinase, the Tie2-Cre transgenic line was crossed with the mouse strain carrying the Smad4 conditional alleles (Smad4(Co/Co)) or the reporter line ROSA26. PCR of multiple tissue DNA from Tie2-Cre; Smad4(Co/+) mice revealed the Cre activity in all tissues containing endothelial cells. We detected pan-endothelial expression of the Cre transgene in Tie2-Cre; ROSA26 double transgenic embryos by lacZ staining. Therefore, this mouse line may serve as a valuable tool for endothelial cell lineage analyses and conditional gene ablation in endothelial cells.

Animals↗

PubMed2005

[Relationships of Aulacophora beetles feeding behavior with cucurbitacin types in host crops].

Aulacophora fermoralis chinensis and Aulacophora cattigarensis are the two related Aulacophora beetles, but their host selectivity and feeding behavior are significantly different. A. fernzoralis chinensis usually feeds upon Cucumis sativus and Cucurbita moschata, but never upon Luffa acutangula, Momordica charantia and Citrullas lanatus. Its feeding behavior on hosts is to snip a circular trench on their leaves, and then, to feed the leaf tissues isolated by the trench. On the contrary, A. cattigarensis only feeds L. acutangula, and its trenching behavior rarely occurs. This study showed that the host selectivity and feeding behavior of the two beetles were significantly correlated with the types of cucurbitacin biosynthesized by host melon crops. C. sativus and C. moschata might be induced to produce cucurbitacin I by A. fermoralis chinensis feeding, and this compound was responsible for feeding deterrent on A. fermoralis chinensis. Therefore, the feeding behavior of A. fermoralis chinensis was to block the translocation of cucurbitacin I to feeding sites. M. charantia and C. lanatus contained deterrent cucurbitacin D, and thus, both beetles never fed upon them, while L. acutangula contained stimulants cucurbitacin B and E, and made A. cattigarensis directly feed upon it without trenching. The results suggested that the taste responses of insects on specific allelochemicals from plants may play an important role in host selectivity and feeding behavior.

Animals↗

PubMed2005

[Expression of peroxisome proliferators-activated receptor gamma and alpha-smooth muscle actin in unilateral ureteral obstruction in rats].

OBJECTIVE: To evaluate the expression of peroxisome proliferators-activated receptor gamma (PPAR gamma) and alpha-smooth muscle actin (alpha-SMA) in unilateral ureteral obstruction (UUO) in rats and the relationship between them and the extent of tubulointerstitial injury. METHODS: Male SD rats were randomly subjected to either left ureteral ligation (n=30) or sham operation (n=6), and they were sacrificed on 3, 7, 14, 21 or 28 days after UUO. Sections of renal tissue were stained with hematoxylin and eosin (HE), Masson, or periodic acid-silver methenamine (PASM). The extent of tubulointerstitial injury was determined by Banff classification. Immunohistochemical staining was performed to investigate the expression of PPAR gamma and alpha-SMA in the renal tissue. RESULTS: Swelling of tubular epithelia cells, infiltration of inflammatory cells and proliferation of fibroblasts were not so obvious on days 3 and 7 after UUO. A diffuse inflammatory cells infiltration, and massive fibrous hyperplasia were detectable on days 14 and 21 after UUO. Most tubules showed serious damage and replaced by proliferative fibrous tissue on day 28. The expression of PPAR gamma was almost undetectable in sham operation group. However, it was upregulated on day 3 and peaking on day 14, and then it was slightly decreased on days 21 and 28. The expression of alpha-SMA was only found in vascular smooth muscle cells in sham operation group. It was upregulated mainly in some interstitial cells on day 3 and increased with the progression of tubulointerstitial fibrosis. CONCLUSION: PPAR gamma expression increases in rat renal tissue after UUO, but does not always correlate with the extent of the alpha-SMA expression and tubulointerstitial injury. These data suggest that increase in PPAR gamma in renal tissue may play an important role in response to inflammation and fibrosis.

Actins↗

PubMed2005

[Research advance of ligament injury and ligament healing].

OBJECTIVE: To introduce the research advance of the ligament injury and ligament healing. METHODS: Recent original articles related to such aspects of ligament were reviewed extensively. RESULTS: The ligament properties would be influenced when the situations of the biochemistry and biomechanics had changed. Injuries to ligaments induce a healing response that is characterized by scar formation. Graft could not recovery the ultrastructure, anatomy and biomechanics of the normal ligament. CONCLUSION: The healing ligament is weaker than normal one, and the graft could not reconstruct normal ligament at present.

Animals↗

PubMed2005

Topographical evaluation of the decentration of orthokeratology lenses.

PURPOSE: To evaluate the amount of lens decentration and various factors affecting decentration after orthokeratology lens wear and to observe the effect of decentration on the visual functions. METHODS: Two kinds of orthokeratology lenses were fitted to 270 eyes of 135 patients [initial mean refractive error: (-3.98+/-1.51)D]. Humphery Instruments ATLAS 990 was used for the computer-assisted analysis of corneal topographical maps. The examination of corneal topography was performed on patients before and after 6 months of wearing orthokeratology lenses. The amount of decentration of orthokeratology lenses was measured by finding the distance between center of optic zone and the pupil center. The factors influencing the amount of decentration were analyzed, including the initial refraction error, astigmatism, keratometry values, corneal eccentricity, and the diameter of lens. Visual symptoms including monocular diplopia, glare around lights were recorded to evaluate the effects of decentration on visual functions. RESULTS: The mean amount of decentration was (0.49+/-0.34) mm after one night's wear. The mean amount of decentration after 1 month, 3 months and 6 months was (0.57+/-0.41) mm, (0.55+/-0.48) mm and (0.59+/-0.39) mm, respectively. After one month, the amount of decentration was less than 0.50 mm in 51.1% eyes, 0.50-1.0 mm in 35.6% eyes and more than 1.00 mm in 13.3% eyes. The direction of decentration of more than 0.50 mm was mainly in the temporal quadrant (48.5%). Patients with greater initial astigmatism and smaller lenses showed greater decentration (P<0.05). There was no statistically significant difference in decentration between the two groups with different corneal eccentricities and keratometry values (P>0.05). The amount of decentration was greater in patients who complained of monocular diplopia and glare. CONCLUSIONS: The amount of decentration of orthokeratology depends on the initial refractive error, astigmatism and the design of orthokeratology lenses. Improvement in fitting technology and lens design can lead to reduced incidence of decentration and visual symptoms.

Adolescent↗

PubMed2005

[The study of the therapeutic application of PV contact lens].

PURPOSE: To evaluate the indications and effects of continuously wearing the Bausch & Lomb Pure-Vision (PV)Contact Lens. METHOD: Twenty-nine patients (31 eyes) who required therapeutic contact lens wear were selected non-randomly from Zhongshan Ophthalmic Center for wearing (Pure Vision, PV) contact lens. Therapeutic indications included pain and irritation relief, corneal protection, and enhancement of corneal wound healing. Simultaneously antibiotics and artificial tears were used according to the ocular diseases. And then, the effect of treatment, anterior segment of eyes, contact lens fitting characteristics, lens deposits and the presence of contact lens-relative complications were evaluated. RESULTS: The duration of PV contact lens wear on 31 eyes were 3-57 days, averagely 20.9 days. Patients included bullous keratopathy (6 cases, 6 eyes), keratitis incorporated with descemetocele (5 cases, 5 eyes), chemical burns with epithelial abrasions (6 cases, 7 eyes), post-keratoplasty (3 cases, 3 eyes), filamentary keratitis (3 cases, 3 eyes), corneal epithelial erosion syndrome (2 cases, 3 eyes), repetitive corneal epithelial stripping syndrome (1 case, 1 eye), corneal lamellar laceration and epithelial coloboma (1 case, 1 eye), post-extraction of traumatic cataract with durative corneal ulcer (1 case, 1 eye), post-limbal & amnia transplantation (1 case, 1 eye). For the treatment of pain and irritation relief (21 patients, 22 eyes), all patients had complete or partial relief. For corneal healing (20 patients, 22 eyes), full healing was noted in 15 patients (16 eyes) (72.7%), partial healing occurred in 4 patients (5 eyes) (22.7%). For corneal protection (21 patients, 23 eyes), lens wear was fully protective in all cases, except one case of loosely fitting. Our result shows that PV Contact Lens exhibits prominent efficiency in CONCLUSION: treating corneal diseases and ocular surface diseases, as well as corneal protection, corneal healing and pain relief. The lens has increased oxygen transmissibility and good anti-deposit quality, reducing the risk of ocular complications. As a result of these, PV Contact Lens is the ideal bandage therapeutic lens.

Adolescent↗

PubMed2004

Identification of differentially expressed genes in individual bovine preimplantation embryos produced by nuclear transfer: improper reprogramming of genes required for development.

Using an interwoven-loop experimental design in conjunction with highly conservative linear mixed model methodology using estimated variance components, 18 genes differentially expressed between nuclear transfer (NT)- and in vitro fertilization (IVF)-produced embryos were identified. The set is comprised of three intermediate-filament protein genes (cytokeratin 8, cytokeratin 19, and vimentin), three metabolic genes (phosphoribosyl pyrophosphate synthetase 1, mitochondrial acetoacetyl-coenzyme A thiolase, and alpha-glucosidase), two lysosomal-related genes (prosaposin and lysosomal-associated membrane protein 2), and a gene associated with stress responses (heat shock protein 27) along with major histocompatibility complex class I, nidogen 2, a putative transport protein, heterogeneous nuclear ribonuclear protein K, mitochondrial 16S rRNA, and ES1 (a zebrafish orthologue of unknown function). The three remaining genes are novel. To our knowledge, this is the first report comparing individual embryos produced by NT and IVF using cDNA microarray technology for any species, and it uses a rigorous experimental design that emphasizes statistical significance to identify differentially expressed genes between NT and IVF embryos in cattle.

Animals↗

PubMed2004

XBP-1 increases ERalpha transcriptional activity through regulation of large-scale chromatin unfolding.

Human X box binding protein 1 (XBP-1) is a transcription factor essential for hepatocyte growth, the differentiation of plasma cells, and the unfolded protein response. Recently, we have demonstrated that two forms of XBP-1, XBP-1S, and XBP-1U, enhance estrogen receptor alpha (ERalpha)-dependent transcriptional activity in a ligand-independent manner. However, how XBP-1S and XBP-1U regulate ERalpha transcriptional activity remains unknown. Here, we report that XBP-1S and XBP-1U induce large-scale chromatin unfolding by targeting the XBP-1 proteins to an amplified, lac operator-containing chromosome region in mammalian cells. This unfolding activity maps to the transactivation domains of XBP-1S and XBP-1U. Wild-type XBP-1S and XBP-1U, but not the mutants that completely abolished the ERalpha transcriptional activation, increased the chromatin unfolding activity of ERalpha. These data identify a novel function of XBP-1 and suggest that regulation of large-scale chromatin unfolding by XBP-1 may be responsible for the enhancement of ERalpha transcriptional activity.

Cell Differentiation↗

PubMed2004

Highly efficient selection of the stable clones expressing antibody-IL-2 fusion protein by a dicistronic expression vector containing a mutant neo gene.

To increase the selection efficiency and productivity of stable clones expressing recombinant antibody-IL-2 fusion protein, a dicistronic expression vector containing the anti-erbB2 scFv-Fc-IL-2 fusion gene followed by a weakened neo gene, was constructed to allow for the concurrent translation of the recombinant protein and mutated neomycin phosphotransferase from a single mRNA. The presence of the mutant enzyme in the transfectomas resulted in a decreased resistance of cells in the presence of an elevated level of G418 and retarded cell growth. The transfectomas containing the mutant enzyme expressed considerably higher levels of the fusion protein than those containing the normal enzyme. Furthermore, these positive clones had an almost identical level of recombinant gene expression, which was very stable even when the concentration of G418 was significantly increased. Thus, the selection efficiency of strongly positive producers was remarkably increased. Our results demonstrate that the dicistronic expression vector is useful for the selection of highly expressing clones. Combined with an amplification system, this vector may have potential usage for the expression of recombinant antibody and the yield may be further improved by this expression system.

Animals↗

PubMed2004

[Obstruction of TGF-beta1 signal transduction can decrease the process of hepatocellular carcinoma in mice induced by CCl4/ethanol].

OBJECTIVE: To study obstruction of the TGF-beta(1) signal transduction by antisense RNA of Smad(4) and its effects on experimental hepatic carcinoma of mice. METHODS: We used the mouse model of primary hepatic carcinoma induced by CCl(4)/ethanol, and transferred antisense Smad(4)cDNA with retrovirus-mediated via portal vein infusion into liver. Southern Blot confirmed that the antisense Smad(4)cDNA had been integrated into the liver. The antisense Smad(4) gene could down-regulate the expression of Smad(4) in fibrotic liver observed by Northern and Western Blot. RESULTS: In the non-therapeutic cirrhotic liver, the expression of Smad(4) mRNA was significantly increased than normal liver. After antisense Smad(4) gene was transferred, the expression of Smad(4) mRNA in the therapeutic liver was significantly decreased compared with non-therapeutic cirrhotic liver. The fibrotic degree of therapeutic liver was alleviated compared with the non-therapeutic fibrotic liver. No significant difference was found between the rates of carcinogenesis of non-therapeutic cirrhotic liver and that of therapeutic cirrhotic liver. But the diameters and numbers of the liver cancers in the therapeutic cirrhotic group were less than that in the non-therapeutic cirrhotic group. CONCLUSION: These results indicate that the antisense Smad(4) gene not only can obstruct the progression of liver fibrosis, but also can inhibit the progression of liver cancer, by obstructing the signal transduction of TGF-beta1.

Adenoviridae↗

PubMed2004

Role of connective tissue growth factor in renal tubular epithelial-myofibroblast transdifferentiation and extracellular matrix accumulation in vitro.

Connective tissue growth factor (CTGF) has been reported to play an important role in mediating the profibrotic effects of transforming growth factor-beta (TGF-beta) in the pathogenesis of renal fibrosis. To further elucidate the role of CTGF in renal tubular transdifferentiation and extracellular matrix (ECM) metabolism, we examined the time-course of CTGF, alpha-smooth muscle actin (alpha-SMA), fibronectin and plasminogen activator inhibitor-1(PAI-1) gene expression upon the stimulation of TGF-beta1 (5 microg/L) in cultured human proximal tubular epithelial cell line (HKC), and further investigated the effects of endogenous CTGF blockade. On reverse transcriptional-polymerase chain reaction (RT-PCR) analysis, TGF-beta1 upregulated CTGF gene expression, preceding that of alpha-SMA, fibronectin and PAI-1. The alpha-SMA, fibronectin and PAI-1 mRNA expression induced by TGF-beta1 were significantly inhibited by CTGF antisense oligodeoxynucleotide (ODN) transfection. With prolonged incubation time, CTGF antisense ODN also inhibited intracellular alpha-SMA and PAI-1 protein synthesis, lowered the level of fibronectin and PAI-1 protein secreted into the media, as confirmed by indirect immuno-fluorescence, flow cytometry, enzyme-linked immunosorbent assay (ELISA) and Western blot methods respectively. These results suggested that CTGF may play a crucial role in the renal tubular epithelial-transdifferentiation and the following deposition/degradation process of ECM during tubulointerstitial fibrosis.

Actins↗

PubMed2004

CD40 is expressed on rat peritoneal mesothelial cells and upregulates ICAM-1 production.

BACKGROUND: CD40 has been identified on a variety of cell types, and it plays an important role in adaptive immunity and inflammation. Peritoneal mesothelial cells (PMCs) are the main cell layer that line the peritoneal membrane. Previously we found that CD40 ligand (CD154) is functionally expressed on peritoneal macrophages during continuous ambulatory peritoneal dialysis peritonitis. However, there are few studies that have examined both CD40 expression on PMCs and the function of CD40 signalling in peritoneal local defence. The purpose of this study was to determine whether PMCs express CD40 and to investigate potential mechanisms of CD40-CD154 interactions that may be involved in the inflammation of the peritoneal membrane. METHODS: Rat PMCs were harvested from the peritoneal cavity and maintained under defined in vitro conditions. We examined expression of CD40 on PMCs under normal culture or stimulation with interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha) or interleukin (IL)-1 by reverse transcription-polymerase chain reaction and fluorescence-activated cell sorting (FACS) analysis. After activation with CD40 monoclonal antibody (mAb), the expression of intercellular adhesion molecule-1 (ICAM-1) on PMCs was analysed by FACS. RESULTS: A portion of rat PMCs cultured in vitro expressed CD40 constitutively. The expression of CD40 mRNA and protein was upregulated markedly following stimulation with IFN-gamma, but not following IL-1 or TNF-alpha. The expression of ICAM-1 on PMCs was significantly increased after activation of CD40 with IFN-gamma and with CD40 mAb. CONCLUSION: PMCs functionally express CD40. The interaction between CD40 on PMCs and CD154-positive cells in the peritoneal cavity may play an important role in peritoneal local defence and may be involved in the inflammation process of the peritoneum.

Animals↗