Biomedical subjects

He Wang

Publications and source records attributed to He Wang.

At least 19 recordsLinked to original sources

PubMed2026

The transcription factor SbWRKY6 confers cadmium tolerance via activating SbPLAC8-17 expression in sorghum.

Cadmium (Cd) is a widespread environmental pollutant that severely threatens crop productivity and food safety. However, the regulatory mechanisms underlying Cd detoxification and tolerance in sorghum remain largely elusive. Herein, we functionally characterized SbWRKY6, a Cd‑induced WRKY transcription factor that localizes to the nucleus and functions as a transcriptional activator. Stable overexpression of SbWRKY6 significantly enhanced Cd tolerance in sorghum, as evidenced by improved growth performance, mitigated oxidative damage, and decreased Cd concentration in plant tissues, whereas silencing of SbWRKY6 resulted in a Cd-hypersensitive phenotype with exacerbated toxicity symptoms. Mechanistically, we identified SbPLAC8-17, a member of the Plant Cadmium Resistance (PCR)/PLAC8 family, as a critical downstream target of SbWRKY6. Heterologous expression of SbPLAC8-17 functionally complemented the Cd‑sensitive phenotype of the yeast mutant ∆ycf1 and reduced intracellular Cd accumulation. Further yeast one-hybrid (Y1H), electrophoretic mobility shift assay (EMSA), and dual-luciferase reporter (Dual-LUC) assays confirmed that SbWRKY6 directly binds to the SbPLAC8-17 promoter and transcriptionally activates its expression. In vivo silencing of SbPLAC8-17 significantly impaired cellular Cd²⁺ efflux and aggravated Cd toxicity in sorghum. Additionally, the rapid Cd-induced transcriptional upregulation of SbMPK3 and its direct physical interaction with SbWRKY6 suggest a potential upstream regulatory module that remains to be functionally validated. Collectively, this study elucidates a novel SbWRKY6‑SbPLAC8-17 transcriptional cascade that positively regulates Cd tolerance by facilitating Cd²⁺ efflux, providing promising genetic targets for phytoremediation and molecular breeding of safe sorghum cultivars for Cd-contaminated fields.

Sorghum↗

PubMed2006

Inhibition of CD147 expression reduces tumor cell invasion in human prostate cancer cell line via RNA interference.

CD147, also named extracelluar matrix metalloproteinase inducer (EMMPRIN), has been proved to be involved in the invasion and metastasis processes of tumor cells in many types of cancers. To determine the role of CD147 in the invasiveness properties of prostate cancer, we successfully downregulated CD147 by RNA interference (RNAi) technology, in PC-3 cell line at high level of CD147 expression. PC-3 cells were transfected with a pSilencer 4.1-CMV neo Vector coding for an RNA composed of two identical 19-nucleotide sequence motifs in an inverted orientation, separated by a 9-bp spacer to form a hairpin dsRNA capable of mediating target CD147 inhibition. Gelatin zymography was employed to determine the effect on reducing secretions of MMP-2 and MMP-9 of the transfected cells. Matrigel invasion assay was performed to evaluate the invasion ability of PC-3 cells in vitro. Our results showed that CD147 expression was significantly inhibited by small interfering RNAs (siRNA) transfectants in PC-3 cells at mRNA and protein levels, which resulted in dramatic reduction of invasion ability in tumor cells. Moreover, downregulation of CD147 resulted in reducing secretions of MMP-2, MMP-9. Taken together, CD147 downregulation by RNAi technology decreases the invasive capability of prostate cancer cells, demonstrating that stable expression of siRNA CD147 could potentially be an experimental approach for prostate cancer gene therapy.

Antigens, CD↗

PubMed2006

Low expression of glycoprotein subunit 130 in ejaculated spermatozoa from asthenozoospermic men.

Previous studies showed that interleukin-6 (IL-6) was expressed in human Leydig and Sertoli cells and that it inhibited sperm motility. The aim of this study was to compare the expression of IL-6, IL-6R, and GP130 in ejaculated spermatozoa between normozoospermic and asthenozoospermic men. Human spermatozoa in the semen were purified by Percoll gradient technique to separate the seminal plasma and other round cells. RT-PCR, immunocytochemistry, and Western blot were used to detect the expression of IL-6, IL-6R, and GP130 in spermatozoa. With RT-PCR, only GP130 mRNA but not IL-6 and IL-6R mRNA was expressed in human ejaculated spermatozoa. The expression of GP130 mRNA was significantly lower in asthenozoospermic men than in normozoospermic men. The protein expression of GP130 was further confirmed by both immunocytochemistry and Western blot. Again, GP130 protein levels were significantly lower in asthenozoospermic men than in normozoospermic men. The results suggested that the decreased expression of GP130 in ejaculated spermatozoa could be associated with low sperm motility in asthenozoospermic men.

Blotting, Western↗

PubMed2006

The influence of gestation and mechanical ventilation on serum clara cell secretory protein (CC10) concentrations in ventilated and nonventilated newborn infants.

Clara cell secretory protein (CC10) is an important anti-inflammatory mediator in the adult lung, but its role in newborn pulmonary protection is uncertain. We examined the early postnatal behavior of CC10 in newborn serum and tracheal fluid and hypothesized that CC10 production is positively influenced by gestation. Blood from 165 infants from the first, third/fourth, and seventh days of life (gestational ages: 23-29 wk, 30-36 wk, >36 wk) and tracheal fluid (TF) from the first day of life from 32 ventilated infants were analyzed for CC10. Surfactant proteins A (SPA) and B (SPB) were also analyzed from the blood of a subgroup of infants. Serum CC10 on day 1 was highest in term infants (69.4 ng/mL), followed by moderately preterm (55.8 ng/mL), and then extremely preterm infants (median 42.1 ng/mL). Term infants also had higher tracheal fluid CC10 than preterm infants. (20.152 ng/mL versus 882 ng/mL). Mechanical ventilation increased serum CC10 only in moderately preterm infants, and only on d 1 [68.4 ng/mL versus 42.1 ng/mL (nonventilated moderately preterm infants)]. Serum CC10 decreased progressively by the end of the first week in all infants, in contrast to SPA and SPB, which increased. Our results show that CC10 is detectable in the blood of newborn infants and that a production surge occurs at birth. This surge is more pronounced in term infants and may confer them with superior extrauterine pulmonary protection compared with preterm infants.

Aging↗

PubMed2006

Regulation of the human ADAMTS-4 promoter by transcription factors and cytokines.

ADAMTS-4 (aggrecanase-1) is a metalloprotease that plays a role in aggrecan degradation in the cartilage extracellular matrix. In order to understand the regulation of ADAMTS-4 gene expression we have cloned and characterized a functional 4.5kb human ADAMTS-4 promoter. Sequence analysis of the promoter revealed the presence of putative binding sites for nuclear factor of activated T cells (NFAT) and Runx family of transcription factors that are known to regulate chondrocyte maturation and differentiation. Using promoter-reporter assays and mRNA analysis we have analyzed the role of chondrocyte-expressed transcription factors NFATp and Runx2 and have shown that ADAMTS-4 is a potential downstream target of these two factors. Our results suggest that inhibition of the expression/function of NFATp and/or Runx2 may enable us to modulate aggrecan degradation in normal physiology and/or in degenerative joint diseases. The ADAMTS-4 promoter would serve as a valuable mechanistic tool to better understand the regulation of ADAMTS-4 expression by signaling pathways that modulate cartilage matrix breakdown.

ADAM Proteins↗

PubMed2006

A unique role of the DNA fragmentation factor in maintaining genomic stability.

DNA fragmentation is a hallmark of apoptosis (programmed cell death). However, the biological function of apoptotic DNA fragmentation remains unclear. Here, we show that DNA fragmentation factor plays an important role for maintaining genomic stability. Inhibition or loss of the DNA fragmentation factor (DFF)/caspase-activated DNase (CAD), whose nuclease activity is responsible for digesting genomic DNA during apoptosis, led to significant increases in spontaneous or induced gene mutations, gene amplifications, and chromosomal instability in primary mouse cells and transformed human cell lines. The mechanism underlying genetic instability in DFF/CAD-deficient cells, at least in part, involves a small but significant elevation in the survival of cells exposed to ionizing radiation, suggesting that apoptotic DNA fragmentation factor contributes to genomic stability by ensuring the removal of cells that have suffered DNA damage. In support of this hypothesis are the observations of increased cellular transformation of mouse embryonic cells from the DFF/CAD-null mice and significantly enhanced susceptibility to radiation-induced carcinogenesis in these mice. These data, in combination with published reports on the existence of tumor-specific gene mutations/deletions in the DFF/CAD genes in human cancer samples, suggest that apoptotic DNA fragmentation factor is required for the maintenance of genetic stability and may play a role in tumor suppression.

Animals↗

PubMed2006

A novel diagnostic strategy for trisomy 21 using short tandem repeats.

Molecular technique with STRs can rapidly diagnose aneuploidy. In order to improve its fidelity, we developed a novel STR-based strategy for fast diagnosis of trisomy 21 and constructed a multimarker diagnostic system according to it. The system is based on nine STRs, of which two were previously known and seven were newly identified from the genomic sequence of the long arm of chromosome 21. They were confirmed to be highly polymorphic in the Chinese population by PCR amplification and gel electrophoresis. The combination of nine STR markers, when applied to DNA from 102 Chinese individuals with normal karyotype, did not yield any false-positives, and clearly revealed three different alleles in DNA from 15 out of 18 trisomy 21 patients. The results show that our new strategy can provide an alternative molecular technique for the rapid detection of aneuploidy.

Alleles↗

PubMed2006

Effects of rate, volume, and dose of intratumoral infusion on virus dissemination in local gene delivery.

Recent studies have shown that up to 90% of viral vectors could disseminate to normal organs following intratumoral infusion. The amount of dissemination might be dependent on the infusion conditions. Therefore, we investigated the effects of infusion rate, volume, and dose on transgene expression in liver and tumor tissues after intratumoral infusion of an adenoviral vector encoding luciferase. Luciferase expression was determined through bioluminescence intensity measurement. We observed that the luciferase expression in the liver was independent of the infusion rate but increased with the infusion dose, whereas the luciferase expression in the tumor was a bell-shaped function of the infusion rate. The latter observation was consistent with the distribution pattern of Evans blue-labeled albumin after its solution was infused into tumors at the same infusion rates. We also observed that the infusion volume could affect luciferase expression in the tumor but not in the liver. These observations implied that virus dissemination was determined mainly by the infusion dose, whereas the amount of transgene expression in the tumor depended on the distribution volume of viral vectors in the tumor as well as the infusion dose.

Adenoviridae↗

PubMed2006

Transient reduction of PTI-1 expression by short interfering RNAs inhibits the growth of human prostate cancer cell lines.

The prostate tumor-inducing gene 1 (PTI-1) was originally identified by differential ribonucleic acid (RNA) display in human prostate carcinoma. PTI-1 is expressed in human prostate carcinoma but not in benign prostate hypertrophy or normal prostate tissue. PTI-1 may be a member of oncogenes that could affect protein translation and contribute to carcinoma development in human prostate. To investigate the role of PTI-1 in human prostate carcinoma, we constructed three different short interfering RNA (siRNA) vectors (pSilencer3.1-neo-Yu Lei [YL]1-2, -YL3-4 and -YL5-6), each of which was transfected into DU145 and PC3 human prostate cancer cell lines. Among these siRNAs, only pSilencer3.1-neo-YL1-2 could almost completely block the expression of PTI-1 in these two cell lines. The growth of the cell lines was then evaluated after transfection. The proliferation rate was retarded in DU145 and PC3 cells transfected with pSilencer3.1-neo-YL1-2, compared with the cells transfected with a control vector; namely, about 88.6% of DU145 and 80.2% of PC3 cancer cells were blocked at the G1 phase when transfected with pSilencer3.1-neo-YL1-2, compared to 62.0% in DU145 cells and 51.7% in PC3 cells, transfected with the control vector. Moreover, 68.3% of DU145 cells and 72.3% of PC3 cells were induced into apoptosis, while in control transfection, the population was 26.6% in DU145 cells and 28.4% in PC3 cells. These results indicate that blocking PTI-1 expression can inhibit the growth of certain prostate cancer cell lines. We suggest that PTI-1 may serve as a target for the gene-based therapy of human prostate carcinoma.

Adenocarcinoma↗

PubMed2006

[Inhibition of HPV16 E6 oncogene in cervical cancer by RNA interference].

OBJECTIVE: The efficiency of HPV16 E6 gene silenced by RNA interference in vitro and in vivo was assessed. METHODS: The specific siRNA of HPV16 E6 was designed and transfected into CaSki cells by liposome. Cell apoptotic rates and the changes in HPV16 E6 mRNA and protein before and after transfection were measured. Cervical cancer nude mice models were set up, siRNA was injected directly into subcutaneous tumor. The function of siRNA was evaluated by the changes in tumor volume, HPV16 E6 protein expression and apoptosis of tumor cells. RESULTS: In vitro research, the cell apoptotic rates were 7.7%, 11.8%, 37.4% and 12.6% respectively at 24 h, 48 h, 5th day and 9th day after transfection. The HPV16 E6 mRNA was reduced by 77%, 83%, 59% and 41% at 24 h, 48 h, 5th day and 9th day after transfection. The inhibition rates of E6 protein measured by Flow cytometry were 79.7%, 80.4%, 71.3% and 57.4% at 24 h, 48 h, 5th day and 9th day after transfection, which were confirmed by the results of Western blot. In vivo research, E6 siRNA administration groups had great power in inhibiting tumor growth, restraining E6 protein expression, increasing tumor necrosis and apoptosis. The result of repeated injections of siRNA was better than that of single injection. CONCLUSION: RNA interference with HPV16 E6 is specific and highly efficient in vitro and in vivo.

Animals↗

PubMed2006

[Expression of matrix metalloproteinase and tissue inhibitor of metalloproteinase in adenomyosis].

OBJECTIVE: To investigate the expressions of matrix metalloproteinase -2, -3 (MMP-2,-3) and tissue inhibitor of metalloproteinase-2 (TIMP-2) in internal uterine endometriosis tissue and endometrium from women with and without endometriosis throughout the menstrual cycle. METHODS: Immunohistochemical staining of tissues was performed to study the expressions and locations of MMP-2, MMP-3, TIMP-2 between women with and without endometriosis. The real-time PCR technique was applied to detected the mRNA expressions of MMP-2, MMP-3 and TIMP-2. RESULTS: We found that ectopic endometrium from patients with endometriosis expressed higher levels of MMP-2 and MMP-3 and lower levers of TIMP-2 than normal controls did (P < 0.05). MMP-2 and MMP-3 were detected strongly in both stromal and epithelial cells of ectopic endometrium from patients with endometriosis, when mostly detected in the epithelial cells in the control group. All eutopic and ectopic endometrium samples from women with and without endometriosis throughout the menstrual cycle showed similar expressions of MMP-2, MMP-3 and TIMP-2. Quantitative expressions of MMP-2 mRNA, MMP-3 mRNA and TIMP-2 mRNA were significantly lower in eutopic endometrium from controls compared with ectopic endometrium from patients with endometriosis (P < 0.05). Eutopic endometrium from controls in the proliferative phase showed significantly increased expressions of MMP-2 mRNA compared with that in the secretory phase (P < 0.05). CONCLUSION: The results suggest that ectopic endometrium with adenomyosis has more invasiveness and is prone to peritoneal implantation maybe to involved in the high expressions of MMP-2 and MMP-3 and the less expressions of TIMP-2 than endometrium from women without adenomyosis does.

Adult↗

PubMed2006

[Detection of physical status of human papillomavirus 16 in cervical cancer tissue and SiHa cell line by multiplex real-time polymerase chain reaction].

BACKGROUND & OBJECTIVE: The integration of high-risk human papillomavirus (HPV) into host cell genome is one of the major contributing factors to cervical malignant transformation. The detection of HPV integration is helpful for understanding its role in cervical carcinogenesis and tumor progression. However, there is no ideal detection method of HPV physical status for clinical use. The study was to explore an ideal method of detecting the physical status of HPV-16. METHODS: Setting HPV-16 plasmid as standard, multiplex real-time polymerase chain reaction (PCR) using 2 different fluorescent report radicals was used to quantify the copy numbers of E2 and E6 genes for analysis of the physical status of HPV-16 according to E2/E6. Multiplex real-time PCR test and Southern blot results of cervical cancer cell line SiHa and 27 specimens of HPV-16-positive cervical squamous cell carcinoma were compared. RESULTS: There was a linear relationship between the threshold cycle values and the copy numbers of E2 and E6 in both standard curves, with the correlation coefficients of 1.00 and the amplification efficiencies of above 95%. The 95% reference range of plasmid E2/E6 ratio, in which the amount of E2 DNA was equal to that of E6 DNA, was 0.81-1.29. The cut-off value of E2/E6, which was used to distinguish the pure episomal form from a mixed form of episomal and integrated HPV-16, was 0.81 in the multiplex real-time PCR test. HPV-16 was observed to be integrated into the host genome of SiHa cells by multiplex real-time PCR and Southern blot. The coincidence rate of multiplex real-time PCR and Southern blot was 81.5% (22/27) in the cervical squamous cell cancer tissues (kappa=0.844, P<0.001). CONCLUSION: Multiplex real-time PCR test is a rapid, sensitive and reliable method for detecting the physical status of HPV-16 DNA, and is convenient to be applied in paraffin-embedded tissue and small preneoplastic or early neoplastic cervical lesions, even in cervical scrapes which contain a small amount of DNA.

Adult↗

PubMed2006

[Functional expression of adenylyl cyclase and phosphodiesterase in ejaculated human spermatozoa].

OBJECTIVE: To compare the differences of expressions of adenylyl cyclase (AC) and phosphodiesterase (PDE) in ejaculated spermatozoa between healthy volunteers and the patients with asthenospermia. METHODS: Ejaculated spermatozoa were collected from healthy volunteers and the patients with asthenospermia. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect mRNA expression of AC and PDE subtypes in human spermatozoa. The concentrations of cAMP and cGMP in the samples were detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: Compared with healthy volunteers, expression of sAC mRNA and concentration of cAMP were significantly decreased in the patients with asthenospermia (P < 0.01) , while the expression of PDE4C mRNA was significantly increased at the same time (P <0.01). There were no marked differences in the expression of ACIII mRNA and concentration of cGMP between the two groups. CONCLUSION: The sAC down-regulation and PDE4C up-regulation are possible reasons for asthenospermia.

Adenylyl Cyclases↗

PubMed2006

[Biologic activity of bispecific single chain antibody against human gamma-seminoprotein and CD3 molecule].

AIM: To construct a recombinant vector which expresses bispecific single chain antibody (BsscFv) against human gamma-seminoprotein and CD3 molecule and evaluate its biologic activity. METHODS: The BsscFv gene was constructed by the splicing overlap extensive (SOE) PCR and then a flexible peptide linker was inserted between anti-human gamma-seminoprotein single chain Fv gene and anti-CD3 single chain Fv gene. The fusion gene was subcloned into the pSectag2-B plasmid and was expressed in HeLa cell lines. After being analyzed by SDS-PAGE and Western blot, the expressed product was purified through a Ni(2+)-NTA superflow affinity chromatography column. Flow cytometry (FCM) was used to detect the binding activity of BsscFv to CD3(+) cell line Jurkat cells and prostate carcinoma cells LNCaP. In vitro killing effect on target cells (LNCaP) mediated by BsscFv was determined by chromium(51)-release test. The effect of CTLs mediated by BsscFv on inhibiting tumor growth was observed by utilizing nude mice bearing prostate cancer cells. RESULTS: DNA sequencing indicated that BsscFv gene consisted of 1,500 bp, encoding 500 amino acids. SDS-PAGE and Western blot analysis showed that the expressed product with relative molecular mass of 61,000 existed in culture supernatant of Hela cells. Flow cytometry analysis demonstrated that the binding rate of BsscFv to LNCaP cells and Jurkat cells was 54.1% and 53.7%, respectively. In vitro, BsscFv mediated cytotoxicity of CTLs to LNCaP cells as confirmed by chromium(51)-release assay. In prostate cancer nude mouse model, BsscFv inhibited tumor's growth as compared with control group. CONCLUSION: The BsscFv against human gamma-seminoprotein and CD3 molecule possesses certain biologic activity, and in vitro and in vivo it can mediate cytotoxicity of CTLs to prostate cancer cells.

Animals↗

PubMed2005

Enhancement of cancer radiation therapy by use of adenovirus-mediated secretable glucose-regulated protein 94/gp96 expression.

Tumor-derived glucose-regulated protein 94 (GRP94/gp96) has shown great promise as a tumor vaccine. However, current protein-based approaches require the availability of large quantities of tumor tissue, which are often not possible. In addition, the efficacy of immunotherapy is often not ideal when used alone. In this study, we explored the therapeutic efficacy of a combined GRP94/gp96-based genetic immunotherapy and radiation therapy strategy in the weakly immunogenic and highly metastatic 4T1 murine mammary cancer model. An adenovirus encoding a modified, secretable form of GRP94 gene (AdsGRP94) was constructed and evaluated in various antitumor experiments. Lethally irradiated, virus-infected cells were used as vaccines. Adenoviral vectors were also injected directly into tumors in conjunction with tumor irradiation. Vaccination with lethally irradiated, AdsGRP94-infected 4T1 cells completely prevented subsequent tumor growth from challenge inoculations of as many as 10(7) cells per mouse. In established tumor models, vaccinations alone had minimal effect on local and metastatic tumor growth. However, when vaccination was combined with radiation therapy and i.t. AdsGRP94 injections, local tumor growth and pulmonary metastasis were markedly inhibited. In some cases, complete tumor regression was observed. In these cases, the mice were resistant to subsequent tumor challenge and remain tumor free up to 10 months after initial therapy. Our results indicate that combined AdsGRP94-based immunotherapy and radiation therapy may be a potentially effective strategy for cancer treatment.

Adenoviridae↗

PubMed2005

Reversible membrane association of dinitrogenase reductase activating glycohydrolase in the regulation of nitrogenase activity in Rhodospirillum rubrum; dependence on GlnJ and AmtB1.

In the photosynthetic bacterium Rhodospirillum rubrum nitrogenase activity is regulated by reversible ADP-ribosylation of dinitrogenase reductase in response to external so called "switch-off" effectors. Activation of the modified, inactive form is catalyzed by dinitrogenase reductase activating glycohydrolase (DRAG) which removes the ADP-ribose moiety. This study addresses the signal transduction between external effectors and DRAG. R. rubrum, wild-type and P(II) mutant strains, were studied with respect to DRAG localization. We conclude that GlnJ clearly has an effect on the association of DRAG to the membrane in agreement with the effect on regulation of nitrogenase activity. Furthermore, we have generated a R. rubrum mutant lacking the putative ammonium transporter AmtB1 which was shown not to respond to "switch-off" effectors; no loss of nitrogenase activity and no ADP-ribosylation. Interestingly, DRAG was mainly localized to the cytosol in this mutant. Overall the results support our model in which association to the membrane is part of the mechanism regulating DRAG activity.

Bacterial Proteins↗

PubMed2005

Niacin mediates lipolysis in adipose tissue through its G-protein coupled receptor HM74A.

A G-protein coupled receptor to niacin (nicotinic acid) was identified recently but the physiological/pharmacological role of the receptor remains poorly defined. We present our studies to demonstrate that HM74A, but not HM74, binds niacin at high affinities and effectively mediates Gi signaling events in human embryonic kidney HEK293 cells as well as in 3T3L1 adipocytes expressing HM74A. Furthermore, HM74A, but not HM74, expressed in differentiated 3T3L1 adipocytes effectively mediated inhibition of lipolysis by niacin. Our results provided direct evidence indicating that HM74A, but not HM74, was sufficient to mediate anti-lipolytic effect of niacin in adipose tissue.

3T3-L1 Cells↗

PubMed2005

Cloning and functional characterization of the rabbit C-C chemokine receptor 2.

BACKGROUND: CC-family chemokine receptor 2 (CCR2) is implicated in the trafficking of blood-borne monocytes to sites of inflammation and is implicated in the pathogenesis of several inflammatory diseases such as rheumatoid arthritis, multiple sclerosis and atherosclerosis. The major challenge in the development of small molecule chemokine receptor antagonists is the lack of cross-species activity to the receptor in the preclinical species. Rabbit models have been widely used to study the role of various inflammatory molecules in the development of inflammatory processes. Therefore, in this study, we report the cloning and characterization of rabbit CCR2. Data regarding the activity of the CCR2 antagonist will provide valuable tools to perform toxicology and efficacy studies in the rabbit model. RESULTS: Sequence alignment indicated that rabbit CCR2 shares 80 % identity to human CCR2b. Tissue distribution indicated that rabbit CCR2 is abundantly expressed in spleen and lung. Recombinant rabbit CCR2 expressed as stable transfectants in U-937 cells binds radiolabeled 125I-mouse JE (murine MCP-1) with a calculated Kd of 0.1 nM. In competition binding assays, binding of radiolabeled mouse JE to rabbit CCR2 is differentially competed by human MCP-1, -2, -3 and -4, but not by RANTES, MIP-1alpha or MIP-1beta. U-937/rabbit CCR2 stable transfectants undergo chemotaxis in response to both human MCP-1 and mouse JE with potencies comparable to those reported for human CCR2b. Finally, TAK-779, a dual CCR2/CCR5 antagonist effectively inhibits the binding of 125I-mouse JE (IC50 = 2.3 nM) to rabbit CCR2 and effectively blocks CCR2-mediated chemotaxis. CONCLUSION: In this study, we report the cloning of rabbit CCR2 and demonstrate that this receptor is a functional chemotactic receptor for MCP-1.

Amino Acid Sequence↗