OBJECTIVETo investigate the effects of LPS and/or TNF-alpha on periodontal ligament cell (PDLC) proliferation and OPG secretion.

METHODSHealthy premolars extracted for orthodontic reasons from a 12 years old boy were obtained, and periodontal tissues were collected and cultured to obtain PDLCs. Cloned PDLCs were obtained by means of limited dilutions, and were characterized as follows: alkaline phosphatase activity, collagen III production and bone-like nodules formation. LPS and rhTNF-alpha were added into culture media and their effects on PDLC proliferation and OPG secretion were observed. The OPG concentrations in cell culture supernatants were detected by sandwich ELISA. Living cell numbers were demonstrated by MTT test. The average levels of OPG secretion by a single cell were calculated by dividing OPG concentration with MTT result.

RESULTSrhTNF-alpha above 10 micro g/L decreased the mtt and opg detecting results, but increased the opg/mtt values (P < 0.05). However, LPS had no effect on mtt, opg or opg/mtt values. Neither it had any interaction with rhTNF-alpha (P > 0.05).

CONCLUSIONSTNF-alpha prohibits the proliferation of PDLCs but enhances their OPG secretion. However, LPS has no effect on neither side. Our works support the hypothesis that there may be an inverse feedback regulation pattern of increasing periodontal OPG production against local bone resorption activity. PDLCs might not be the natural target cells of LPS' direct cytotoxic effect.

Child ; Glycoproteins ; biosynthesis ; drug effects ; Humans ; In Vitro Techniques ; Lipopolysaccharides ; pharmacology ; Male ; Osteoprotegerin ; Periodontal Ligament ; metabolism ; pathology ; Receptors, Cytoplasmic and Nuclear ; biosynthesis ; drug effects ; Receptors, Tumor Necrosis Factor ; biosynthesis ; drug effects ; Tumor Necrosis Factor-alpha ; pharmacology

OBJECTIVETo study the effects of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] on the expression of osteoprotegerin (OPG) and receptor activator of NF-kappaB ligand (RANKL) mRNA in mouse osteoblasts.

METHODSCalvariae derived from CD-1 neonatal mouse (after born 24 h). Bone samples were processed by the collagenase/trypsin digestion method. Mouse osteoblasts were cultured in vitro. After 48 hours of addition of 1,25(OH)2D3 (0, 10(-8), 10(-9), 10(-11) mol/L) to the culture medium of mouse osteoblasts, the content of the OPG protein in culture medium was estimated with enzyme linked immunosorbent assay. Total RNA was prepared from mouse osteoblasts. mRNA expression of OPG and RANKL were detected by reverse transcription-polymerase chain reaction.

RESULTSThe mRNA expression of OPG in osteoblasts added with 1,25(OH)2D3 significantly decreased compared with the controls, which was markedly dose-dependent. OPG protein production in the medium decreased after treatment with 1,25(OH)2D3. In contrast, RANKL mRNA expression levels in osteoblasts significantly increased after 48 h of culture with 1,25(OH)2D3.

CONCLUSION1,25 (OH)2D3 can stimulate RANKL mRNA expression, but decrease OPG mRNA levels in vitro in mouse osteoblasts.

Animals ; Animals, Newborn ; Calcitriol ; pharmacology ; Carrier Proteins ; biosynthesis ; genetics ; Glycoproteins ; biosynthesis ; genetics ; physiology ; Ligands ; Membrane Glycoproteins ; biosynthesis ; genetics ; Mice ; NF-kappa B ; biosynthesis ; genetics ; Osteoclasts ; metabolism ; physiology ; Osteoprotegerin ; RANK Ligand ; RNA, Messenger ; biosynthesis ; genetics ; Receptor Activator of Nuclear Factor-kappa B ; Receptors, Cytoplasmic and Nuclear ; analysis ; biosynthesis ; genetics ; physiology ; Receptors, Tumor Necrosis Factor ; biosynthesis ; genetics ; Tumor Necrosis Factor-alpha ; biosynthesis ; genetics

In this study we used two types of cell cultures, i.e., anchorage-dependent basket and full suspension batch cultures of sTNFRII-gAD-expressing CHO cells in the CelliGen 310 bioreactor (7.5 L) to compare their yields in order to optimize the culturing conditions for efficient expression of sTNFRII-gAD fusion protein consisting of soluble tumor necrosis factor receptor II and globular domain of adiponectin. The anchorage-dependent basket culture was performed in 4L 10% serum-containing medium with the final inoculating concentration of 3 x 10(5) to 4 x 10(5) cells/mL of sTNFRII-gAD-expressing CHO cells for 3 days, and then switched to 4 L serum-free LK021 medium to continue the culture for 4 days. The full suspension batch culture was carried out in the 4 L serum-free LK021 medium with the final inoculating concentration of 3 x 10(5) to 4 x 10(5) cells/mL of sTNFRII-gAD-expressing CHO cells for 7 days. The culturing conditions were monitored in real-time to maintain pH and dissolved oxygen stability through the whole process. The supernatants were collected by centrifuge, and the protein was concentrated through Pellicon flow ultrafiltration system and then purified by DEAE anion exchange. The results showed that the yields of sTNFRII-gAD fusion protein were 8.0 mg/L with 95% purity and 7.5 mg/L with 98% purity in the anchorage-dependent basket and the full suspension batch cultures, respectively. The study provided the framework for the pilot production of sTNFRII-gAD fusion protein.
Adiponectin ; biosynthesis ; genetics ; Animals ; Bioreactors ; CHO Cells ; Cell Culture Techniques ; methods ; Cricetinae ; Cricetulus ; Receptors, Tumor Necrosis Factor, Type II ; biosynthesis ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics

In order to get soluble TNF receptor (sTNFR) II with good neutralizing activity against TNFalpha, we constructed the fusion gene sTNFRII-gAD, which encoded human sTNFR II and the globular domain of adiponectin (gAD), and then expressed it in mammalian cells and analyzed its anti-TNFalpha activity. First, sTNFRII cDNA was obtained by RT-PCR from the total RNA of human peripheral blood lymphocytes, and fused in frame with gAD gene. Then, the fusion gene sTNFRII-gAD was cloned into the expression vector pAAV2neo to result in the plasmid pAAV2neo-sTNFRII-gAD. By immunofluorescent staining with monoclonal antibody either against TNFRII or against adiponectin, we demonstrated that the pAAV2neo-s7NFRII-gAD-transiently-transfected BHK-21S cells were positive. To obtain G418-resistant BHK-21S/pAAV2neo-sTNFRII-gAD cells, we cultured the transfected BHK-21S cells above in 10% FBS containing DMEM media with 800 microg/mL G418 for 15 days, and changed the serum-containing culture media to a serum-free chemically defined media so as to change the cells culturing style from adhesion to suspension. 24 hours later, we harvested the supernatant of the culture for sTNFRII-gAD fusion protein characterization and anti-TNFalpha activity analysis. With monoclonal antibody either against TNFRII or against adiponectin, the Western blotting analysis showed that the sTNFRII-gAD fusion protein was expressed and existed as monomer, trimer and multimer forms in the supernatant. The bioactivity assay demonstrated that the sTNFRII-gAD fusion protein had the ability to neutralize TNFalpha so as to inhibit the cytotoxicity of TNFalpha on L929 cells. Put together, this study has laid the groundwork for large-scale preparation of sTNFRII-gAD fusion protein.
Adiponectin ; biosynthesis ; genetics ; Animals ; Cells, Cultured ; Cricetinae ; Humans ; Protein Structure, Tertiary ; genetics ; Receptors, Tumor Necrosis Factor, Type II ; biosynthesis ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; pharmacology ; Solubility ; Tumor Necrosis Factor-alpha ; antagonists & inhibitors

OBJECTIVEThis study was carried out to investigate the effects of insulin-like growth factor-II (IGF-II) and basic fibroblast growth factor (bFGF) on osteoprotegerin (OPG) secretion of periodontal ligament cells (PDLCs).

METHODSHealthy human premolars extracted for orthodontic reasons from 12-14 years old donators were obtained, and periodontal tissues were collected and cultured to obtain PDL cells. Primary or first passage PDLCs were cloned by means of limited dilutions. PDLCs with osteoblastic phenotypes were characterized as follows: Alkaline phosphatase activity, collagen III production and bone-like nodules formation. IGF-II and bFGF were added into culture media and their effects on PDLCs proliferation and OPG secretion were observed. The OPG concentrations in cell culture supernatants were detected by sandwich ELISA. Living cell numbers were demonstrated by MTT test. The average levels of OPG secretion by a single cell were calculated by dividing OPG concentration with MTT-test result.

RESULTSBoth IGF-II and bFGF upregulated the mtt values (P < 0.05), but ICF-II downregulated the opg/mtt values (P < 0.05), whereas bFGF had no significant effect on opg/mtt values (P > 0.05).

CONCLUSIONIGF-II enhances the proliferation of PDL cells but prohibits OPG secretion. Although bFGF has the same effect on the proliferation of PDL cells, it has no effect on OPG secretion. Before cytokines were used to enhance periodontal regeneration, their effects on local bone balance should also be studied.

Adolescent ; Cells, Cultured ; Child ; Fibroblast Growth Factor 2 ; pharmacology ; Glycoproteins ; biosynthesis ; Humans ; Insulin-Like Growth Factor II ; pharmacology ; Osteoprotegerin ; Periodontal Ligament ; cytology ; drug effects ; metabolism ; Receptors, Cytoplasmic and Nuclear ; biosynthesis ; Receptors, Tumor Necrosis Factor ; biosynthesis

OBJECTIVETo express human osteoprotegerin (OPG) in E. Coli and analyze its bioactivity in vitro.

METHODSSynthetic oligonucleotides were used to amplify human OPG gene by RT-PCR from total RNA of human osteosarcoma cell line MG63. The OPG cDNA coding for 380 amino acid residues was inserted into prokaryotic expression vector pRSET-A, transformed into competent E. Coli BL21, and induced by 0.1 mmol/l IPTG. SDS-PAGE and Western blot were performed to identify OPG-6His fusion protein. After purified by affinity chromatography, 1,000 microg/L or 1,500 microg/L of OPG-6His were added into the mouse bone marrow cells culture medium. The number of tartrate-resistant acid phophatase (TRAP)-positive multinucleated cells and resorption pits were counted to assess the bioactivity of expression products.

RESULTSThe sequence of OPG mature peptide encoding cDNA obtained in this experiment was as same as reported. SDS-PAGE showed 24% of total bacterial protein was of OPG-6His fusion protein. Western blot assay demonstrated that the molecular weight of recombinant protein was about 46 KD and could react specifically with human anti-OPG antibody. The mouse bone marrow cells were induced by 1alpha, 25-dihydroxyvitaminD3 (10(-8) mol/L) and Dexamethasone (10(-7) mol/L) to form osteoclastic-like multinucleated cells. 1,500 microg/L of purified OPG-6His protein could decrease the number of resorption pits and TRAP-positive multinucleated cells in vitro (P < 0.05), but it didn't show the same effects when the concentration of OPG-6His fusion protein was of 1,000 microg/L.

CONCLUSIONSHuman OPG-6His fusion protein is expressed and purified in E. Coli. The expression products have moderate inhibitory effects on osteoclast differentiation and bone resorption in vitro only when excessive amount of proteins are added into the culture medium, indicating that prokaryotic expression of fuctionalal OPG protein awaits further investigation.

Cell Differentiation ; drug effects ; Cell Line, Tumor ; Cloning, Molecular ; Escherichia coli ; genetics ; Glycoproteins ; biosynthesis ; genetics ; Humans ; Osteoclasts ; drug effects ; physiology ; Osteoprotegerin ; Receptors, Cytoplasmic and Nuclear ; biosynthesis ; genetics ; Receptors, Tumor Necrosis Factor ; Recombinant Fusion Proteins ; biosynthesis ; pharmacology

AIMTo study the effects of TNF receptor blocking peptide on adjuvant arthritis in rats.

METHODSThe model of rat adjuvant arthritis was induced by injection of complete Freund's adjuvant. The TNF receptor blocking peptide was injected locally in the ankle. The ankle swelling, the pathologic changes in the ankle joint and the expression of IL-1 beta mRNA and TNF-alpha mRNA by peritoneal macrophages (RT-PCR) were observed.

RESULTSThe model of rat adjuvant arthritis induced by injection of complete Freund's adjuvant was similar to human rheumatoid arthritis. The treatment with TNF receptor blocking peptide for 10 days resulted in complete inhibition of joint swelling, a decrease in infiltration of inflammatory cell into joint tissue, an obvious alleviation of inflammatory pathological damages and an apparent decline of TNF-alpha mRNA and IL-1 beta mRNA of peritoneal macrophages of rats.

CONCLUSIONThe TNF receptor blocking peptide can protect the joint from inflammatory damage induced by adjuvant arthritis by suppression of TNF-alpha and IL-1 production, thereby alleviating the pathological injury of joint and controlling effectively the clinic course of arthritis.

Animals ; Ankle Joint ; pathology ; Arthritis, Experimental ; immunology ; pathology ; Interleukin-1 ; biosynthesis ; genetics ; Macrophages, Peritoneal ; metabolism ; Male ; Peptides ; pharmacology ; RNA, Messenger ; genetics ; Rats ; Rats, Wistar ; Receptors, Tumor Necrosis Factor ; antagonists & inhibitors ; Tumor Necrosis Factor-alpha ; biosynthesis ; genetics

Recent studies indicate that several Toll-like receptors (TLRs) are implicated in recognizing viral structures and instigating immune responses against viral infections. The aim of this study is to examine the expression of TLRs and proinflammatory cytokines in viral skin diseases such as verruca vulgaris (VV) and molluscum contagiosum (MC). Reverse transcription-polymerase chain reaction and immunostaining of skin samples were performed to determine the expression of specific antiviral and proinflammatory cytokines as well as 5 TLRs (TLR2, 3, 4, 7, and 9). In normal human skin, TLR2, 4, and 7 mRNA was constitutively expressed, whereas little TLR3 and 9 mRNA was detected. Compared to normal skin (NS), TLR3 and 9 mRNA was clearly expressed in VV and MC specimens. Likewise, immunohistochemistry indicated that keratinocytes in NS constitutively expressed TLR2, 4, and 7; however, TLR3 was rarely detected and TLR9 was only weakly expressed, whereas 5 TLRs were all strongly expressed on the epidermal keratinocytes of VV and MC lesions. In addition, the mRNA expression of IFN-beta and TNF-alpha was upregulated in the VV and MC samples. Immunohistochemistry indicated that IFN-beta and TNF-alpha were predominately localized in the granular layer in the VV lesions and adjacent to the MC bodies. Our results indicated that VV and MC skin lesions expressed TLR3 and 9 in addition to IFN-beta and TNF-alpha. These viral-induced proinflammatory cytokines may play a pivotal role in cutaneous innate immune responses.
Cytokines/metabolism ; *Gene Expression Regulation ; Humans ; Immunohistochemistry/methods ; Inflammation ; Interferon-beta/biosynthesis ; Keratinocytes/cytology ; Models, Biological ; Molluscum Contagiosum/*metabolism ; Toll-Like Receptor 3/biosynthesis ; Toll-Like Receptor 9/biosynthesis ; Toll-Like Receptors/*biosynthesis ; Tumor Necrosis Factor-alpha/biosynthesis ; Warts/*metabolism

OBJECTIVETo detect the expression of recombinant plasmid PcDNA3.1-sTNFRI in vitro and evaluate the bioactivity of expressed sTNFRI.

METHODSCHO cells were transfected with recombinant plasmid PcDNA3.1-sTNFRI by liposome. sTNFRI in cell culture supernatant was detected by ELISA and sTNFRI blockage of TNF-alpha cytotoxicity in L929 cells evaluated by MTT assay.

RESULTSThe expression of sTNFRI in transfected cell culture supernatant was higher than control groups (P < 0.001). The expressed sTNFRI could significantly neutralize TNF-alpha cytotoxicity in L929 cells.

CONCLUSIONSThese results showed that the recombinant plasmid PcDNA3.1-sTNFRI can be expressed in mammalian cells and the recombinant sTNFRI has biological function.

Animals ; Antigens, Surface ; biosynthesis ; CHO Cells ; Cloning, Molecular ; Cricetinae ; DNA, Complementary ; biosynthesis ; genetics ; Eukaryotic Cells ; metabolism ; Genetic Vectors ; drug effects ; Humans ; Plasmids ; biosynthesis ; genetics ; Receptors, Tumor Necrosis Factor, Type I ; biosynthesis ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; pharmacology ; Transfection

AIMTo establish methods and requirements for quality control of recombinant human tumor necrosis factor receptor Fc fusion protein (rhTNFR-Fc).

METHODSBiological potency of rhTNFR-Fc was determined by neutralizing the bioactivity of TNF-alpha. rhTNFR-Fc samples were reduced by beta-mercaptoethanol and the peptide map was performed by tryptic digestion. Residual protein A and the host cell protein content were detected by ELISA. Anti-TNFR and anti-Fc antibodies were used in ELISA for detection of the rhTNFR-Fc content.

RESULTSThe quality control methods, such as bioassay, peptide map, residual protein A detection, were established and used for quality control of rhTNFR-Fc. The unit of rhTNFR-Fc (AU) was defined according to the international unit of TNF-alpha. The specific activity was up to 8 x 10(4) AU.mg-1. The requirements for quality control of rhTNFR-Fc were established.

CONCLUSIONThe methods and requirement were used for quality control of rhTNFR-Fc products.

Animals ; Biotechnology ; methods ; Cell Division ; drug effects ; Etanercept ; Immunoglobulin G ; biosynthesis ; chemistry ; pharmacology ; Mice ; Peptide Mapping ; Quality Control ; Receptors, Tumor Necrosis Factor ; biosynthesis ; chemistry ; Recombinant Fusion Proteins ; biosynthesis ; chemistry ; pharmacology ; Technology, Pharmaceutical ; standards ; Tumor Cells, Cultured