Presence of β2-Microglobulin on B- and T-Cells and Lymphocytotoxicity of Anti-β2-Microglobulin Sera

Isolated normal lymphocytes and those of patients with chronic lymphocytic leukemia were shown by immunofluorescence to bear β₂-microglobulin in or on their membranes. Isolated thymocytes displayed similar membrane-associated fluorescence. These findings indicate that both B- and T—cells carry B₂-microglobulin in or on their membranes. Antisera against β₂-microglobulin were found to be cytotoxic in the presence of complement to normal and tissue culture lymphocytes. The presence of β₂-microglobulin found on cells other than B- and T-lymphocytes and the possible function(s) of β₂-microglobulin is discussed.     

Expression and purification of Ctomp2aa167-aa434 and preparation of its mAb

Chlamydia trachomatis outer membrane protein 2 (Ctomp2) is a major immunogen in chlamydial infections and a highly genus-conserved structural protein of all Chlamydia species . To purify the protein and to prepare monoclonal antibodies (mAbs) against it, the recombinant protein was induced by IPTG, which was confirmed by SDS-PAGE and purified by means of a Ni2 -charged resin column. The denatured protein was refolded in the GSH-GSSH buffer gradually and identified by Western blotting. Then the BALB/c mice were immunized with the recombinant protein to prepare the mAb against Ctomp2. The obtained mAbs were characterized. Genital specimens were tested with indirect ELISA mostly made of the mAb and cell culture in 84 patients with genital symptoms. The results showed that high-level expression of the recombinant protein was achieved, which existed as inclusion body and amounted to 38 % of total bacterium protein. A mAb against Ctomp2 was obtained. It belongs to IgG 2b. The titers were as high as 1:40 000. The Western blotting showed that the mAb only reacted with the recombinant protein. It had no crossing reactions against E. coli, N. gonorhoea, M. hominis, U. urealyticum and M. penetrans . It had high specifity. In comparison with gold standard test-cell culture, the sensitivities, specificities, positive predictive values and negative predictive values of indirect ELISA were 95.24%, 100%, 100% and 98.44%, respectively. The above-mentioned research work contributed not only to the further study of the structure and function of this protein , but also to the establishment of the method for its clinical application, for it had not been reported before.     

Distribution pattern of matrix metalloproteinases 1, 2, 3, and 9, tissue inhibitors of matrix metalloproteinases 1 and 2, and α2-macroglobulin in cases of generalized AA- and AL amyloidosis

Matrix metalloproteinases (MMPs) degrade basement membranes and connective tissue and play an essential role in the homeostasis of the extracellular matrix which is disrupted by the deposition of amyloid. This immunohistochemical study investigated the distribution pattern of matrix metalloproteinases (MMP-1, -2, -3, and -9) and their inhibitors [alpha 2-macroglobulin (alpha 2-M), tissue inhibitors of MMPs (TIMP)-1, and TIMP-2] in human AA- and AL amyloid deposits. Specimens of liver, kidney, and spleen from 22 autopsy cases were investigated. Nine patients had suffered from generalized AA amyloidosis, eight from generalized AL amyloidosis, and five from rheumatoid arthritis or tuberculosis with no histological evidence of amyloid. In all amyloidotic and non-amyloidotic patients, each protease and protease inhibitor was detected in almost every organ investigated. In the amyloidotic cases, there was no indication that a specific protease or protease inhibitor was absent or expressed, but a difference was observed in their spatial distribution patterns. The most noticeable difference was found in immunostaining of amyloid. Only MMP-1, -2, and -3, and alpha 2-M were present in AA amyloid deposits, and only TIMP-1 and TIMP-2 were found in deposits of AL amyloid. This is the first study to show that MMP-1, -2, and -3 are present in AA amyloid deposits. They may be involved in tissue remodeling or in proteolysis of the precursor and fibril proteins.     

Hepatic levels of prostaglandins F2α and I2 (prostacyclin) and of thromboxane A2 in dogs developing hemorrhagic shock

Professorial Department of Surgery, L'vov Medical Institute. L'vov Branch, Kiev Research Institute of Hematology and Blood Transfusion. (Presented by Academician of the Academy of Medical Sciences of the USSR V. S. Savel'ev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 2, pp. 134–135, February, 1992.     

Construction and expression of lentiviral vector of rat β-defensin-2 gene

Objective To construct a lentiviral expression vector of rat β-defensin-2(rBD2)gene, and examine its expression by transfected cultured cells,in order to lay the foundation for experiments in vivo.Methods The totaI RNA of rat epithelial ceils was extracted and rBD2 gene was got with PCR amplification.After double-digested and connected the PCR production and lentiviral vector Lentivirus [containing H1 promoter and green fluorescent protein(GFP)],the lentiviral expression vector of rBD2 gene LV-rBD2 was constructed and confirmed by sequencing.The virus-like particles of LV-rBD2 was packed with lentiviral packaging systems and viral titer was determinated by slow-gradient dilution.Expression of rBD2 was tests with RT-PCR and Western Blot after cultured cells had been infected by LV-rBD2.Results The results of gel electrophoresis and DNA sequencing showed that the rBD2 gene was cloned into the lentiviral vector,the sequence is correct.The lentiviral vector particle packaging was complete.the virus titer was adjusted to 1×105 ifu/μl.RT-PCR and Western-blot showed that rBD-2 gene was expressed.Conclusion The lentiviral expression vector of rBD2 gene LV-rBD2 was constructed successful,and could transfecte cells to express rBD2.     

Construction and expression of lentiviral vector of rat β-defensin-2 gene

Objective To construct a lentiviral expression vector of rat β-defensin-2(rBD2)gene, and examine its expression by transfected cultured cells,in order to lay the foundation for experiments in vivo.Methods The totaI RNA of rat epithelial ceils was extracted and rBD2 gene was got with PCR amplification.After double-digested and connected the PCR production and lentiviral vector Lentivirus [containing H1 promoter and green fluorescent protein(GFP)],the lentiviral expression vector of rBD2 gene LV-rBD2 was constructed and confirmed by sequencing.The virus-like particles of LV-rBD2 was packed with lentiviral packaging systems and viral titer was determinated by slow-gradient dilution.Expression of rBD2 was tests with RT-PCR and Western Blot after cultured cells had been infected by LV-rBD2.Results The results of gel electrophoresis and DNA sequencing showed that the rBD2 gene was cloned into the lentiviral vector,the sequence is correct.The lentiviral vector particle packaging was complete.the virus titer was adjusted to 1×105 ifu/μl.RT-PCR and Western-blot showed that rBD-2 gene was expressed.Conclusion The lentiviral expression vector of rBD2 gene LV-rBD2 was constructed successful,and could transfecte cells to express rBD2.     

Axenfeld�CRieger syndrome and spectrum of PITX2 and FOXC1 mutations

Axenfeld–Rieger syndrome (ARS) is a rare autosomal dominant disorder, which encompasses a range of congential malformations affecting the anterior segment of the eye. ARS shows genetic heterogeneity and mutations of the two genes, PITX2 and FOXC1, are known to be associated with the pathogenesis. There are several excellent reviews dealing with the complexity of the phenotype and genotype of ARS. In this study, we will attempt to give a brief review of the clinical features and the relevant diagnostic approaches, together with a detailed review of published PITX2 and FOXC1 mutations.     

Role of proteinase-activated receptor-2 in anti-bacterial and immunomodulatory effects of interferon-γ on human neutrophils and monocytes

Recent studies show that proteinase-activated receptor-2 (PAR(2)) contributes to the development of inflammatory responses. However, investigations into the precise role of PAR(2) activation in the anti-microbial defence of human leucocytes are just beginning. We therefore evaluated the contribution of PAR(2) to the anti-microbial response of isolated human innate immune cells. We found that PAR(2) agonist, acting alone, enhances phagocytosis of Staphylococcus aureus and killing of Escherichia coli by human leucocytes, and that the magnitude of the effect is similar to that of interferon-γ (IFN-γ). However, co-application of PAR(2) -cAP and IFN-γ did not enhance the phagocytic and bacteria-killing activity of leucocytes beyond that triggered by either agonist alone. On the other hand, IFN-γ enhances PAR(2) agonist-induced monocyte chemoattractant protein 1 (MCP-1) secretion by human neutrophils and monocytes. Furthermore, phosphoinositide-3 kinase and janus kinase molecules are involved in the synergistic effect of PAR(2) agonist and IFN-γ on MCP-1 secretion. Our findings suggest a potentially protective role of PAR(2) agonists in the anti-microbial defence established by human monocytes and neutrophils.     

Study of DNA damage induction and repair capacity of fresh and cryopreserved lymphocytes exposed to H2O2 and γ-irradiation with the alkaline comet assay

The alkaline SCGE assay was evaluated for use with cryopreserved lymphocytes in order to obtain results similar to the freshly isolated ones. The induction of DNA damage as well as the repair capacity of γ-rays and H₂O₂ exposed cryopreserved human lymphocytes was found to be the same to that of the freshly isolated. Human lymphocytes (fresh or cryopreserved) responded differently to the effects of γ-irradiation if compared to the H₂O₂ treatment. The distribution of DNA damage among γ-irradiated lymphocytes was more homogeneous compared to H₂O₂, both in freshly isolated and in cryopreserved cells. 2.4 μg/ml phytohemagglutinin at the start of a 2-h incubation in RPMI of cryopreserved samples gave similar DNA repair and distribution patterns to the 2-h post-exposure incubation of freshly isolated lymphocytes. H₂O₂-induced DNA damage was not repaired completely. However, the repair of γ-rays-induced DNA damage was more efficient. These findings confirm the different mode of action of the two agents on the induction of DNA damage, as well as, the different response of the lymphocytes' DNA repair system.     

Transmission heterogeneities,kinetics, and controllability of SARS-CoV-2

A long-standing question in infectious disease dynamics concerns the role of transmission heterogeneities,which are driven by demography,behavior,and interventions.On the basis of detailed patient and contact-tracing data in Hunan,China,we find that 80% of secondary infections traced back to 15% of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)primary infections,which indicates substantial transmission heterogeneities.Transmission risk scales positively with the duration of exposure and the closeness of social interactions and is modulated by demographic and clinical factors.     

Assessment of caspofungin susceptibility of Candida glabrata by the Etest®, CLSI,and EUCAST methods,and detection of FKS1 and FKS2 mutations

Candida glabrata has emerged as a major pathogen in invasive candidiasis in recent years. Currently, guidelines for invasive candidiasis treatment recommend fluconazole or an echinocandin as the first-line therapy. Nevertheless, the resistance of Candida glabrata to echinocandin is an emerging problem and has been partly associated with mutations in the FKS1 and FKS2 genes. The Etest® is an appropriate method for determining antifungal susceptibility in emergency routine diagnosis. In this work, we evaluated the reliability of the Etest® in comparison with the two reference broth microdilution methods, Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST), to assess the caspofungin resistance of 193 isolates of Candida glabrata. The interpretation of minimum inhibitory concentration (MIC) values was also discussed according to different breakpoints. Moreover, FKS1 and FKS2 mutations were investigated for isolates with high MICs. Our results showed that the MIC₅₀ value was similar to the MIC₉₀ value for each method. The Etest® method showed the lowest MIC values, whereas EUCAST presented the highest. Categorical agreement between the Etest® and CLSI methods was 100 % and 36 % using the breakpoints proposed by Arendrup et al. (Antimicrob Agents Chemother 56(7):3965–3968, 2012) and Pfaller et al. (Int J Antimicrob Agents 38(1):65–69, 2011), respectively. Two isolates showed high MIC values with the three methods and both presented FKS2 mutations. A novel FKS2 mutation was also reported for one isolate. Future epidemiological studies should also evaluate the reliability of the Etest® to detect echinocandin resistance, as it remains a routine method.     

Molecular cloning of genes flhA and flhB_2 for flagellar biosynthesis of Leptospira interrogans and functional prediction of the prokaryotic expressing products

Leptospirosis is a worldwide zooanthroponosis thatis common in waterlogging areas and rice paddies[1] .Chinais one of the widelyspreadarea of thisdisease.Leptospiraincludes two species :Lepto-spira interrogansandLeptospira biflexa. Theformer is pathogenic for humans and animals andthe latteris saprophytic which usually existsinthesurface of waters and soils .Sofar ,no anytypicalexotoxins ofLeptospira interroganshas beenfound,and the content and toxicity of lipopolys-sachride fromL.interrogan…     

Immunochemical identification and physicochemical characteristics of the specificα 2-globulin of human granulocytes

Research Institute of Transplantology and Artificial Organs, Ministry of Health of the USSR. Department of Biochemistry, N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR T. T. Berezov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 109, No. 4, pp. 353–355, April, 1990.     

Expression of FGF10 and FGFR2Ⅲb in development of mouse kindey

目的 观察FGF10及其受体FGFR2Ⅲb在小鼠肾脏发生发育中的表达和分布,探讨其在肾脏发生发育中的作用.方法 选取胚龄12、14、16及18 d和出生后1、7、14、21及42 d小鼠肾组织,用免疫组织化学和Western blot,检测FGF10和FGFR2Ⅲb的表达.结果 胚龄12 d组FGF10及FGFR2Ⅲb开始在输尿管芽微弱表达;随着肾脏发育成熟,FGF10及FGFR2Ⅲb主要表达于远端小管和集合管;FGF10在近曲小管表达,近直小管无表达;FGFR 2Ⅲb在近端小管无阳性表达;生后肾组织及发育各阶段肾小体未见FGF10及FGFR2Ⅲb表达.Western blot显示随着胚(日)龄的增加,FGF10及FGFR2Ⅲb在肾脏的表达量先增后减.结论 FGF10和FGFR2Ⅲb在肾脏发生发育过程中发挥重要作用.     

Co-segregation of MEN2 and Hirschsprung's disease: the same mutation of RET with both gain and loss-of-function?

Multiple endocrine neoplasia type 2 (MEN2) and Hirschsprung's disease (HSCR) are two dominantly inherited neurocristopathies ascribed to mutations in the RET gene [Chakravarti, 1996; Pasini et al., 1996; Eng and Mulligan, 1997]. MEN2 is a cancer syndrome comprising three related clinical subtypes: (1) MEN type 2A (MEN2A; MIM# 171400) characterized by the association of medullary thyroid carcinoma (MTC), pheochromocytoma (Pheo), and hyperparathyroidism; (2) MEN type 2B (MEN2B; MIM# 162300), which includes MTC, Pheo, mucosal neuromas, ganglioneuromatosis of the digestive tract, and skeletal abnormalities; and (3) familial MTC (FMTC; MIM# 155240), defined by the sole occurrence of MTC. HSCR (MIM# 142623) is a congenital malformation caused by the absence of enteric plexuses in the hindgut, leading to bowel obstruction in neonates. The RET gene (MIM# 164761) codes for a transmembrane tyrosine kinase, a component of a multimeric complex that also comprises one of four members of a novel family of glycosylphosphatidylinositol (GPI)-anchored receptor, GFRalpha((1-4) (e.g., GFRA1, MIM# 601496; references are detailed in Baloh et al. [1998]. Four structurally related soluble factors-glial cell line-derived neurotrophic factor (GDNF), neurturin, persephin, and artemin-are the ligands of these multimolecular receptors in which the nature of the GFRalpha determines the ligand specificity of the complex [see Baloh et al., 1998, for references]. It is well documented that RET/GFRalpha-1/GDNF delivers a signal critical for the survival of the early neural crest-derived precursors that colonize the intestine below the rostral foregut and give rise to the enteric nervous plexuses [Gershon, 1997; Cacalano et al., 1998; Enomoto et al., 1998].     

Sulforaphane Inhibits IL-1β-Induced Proliferation of Rheumatoid Arthritis Synovial Fibroblasts and the Production of MMPs,COX-2, and PGE2

This study was performed to define the effects of sulforaphane on interleukin-1β (IL-1β)-induced proliferation of rheumatoid arthritis synovial fibroblasts (RASFs), the expression of matrix metalloproteinases (MMPs) and cyclooxygenase (COX), and the production of prostaglandin E2 (PGE2) by RASFs. The proliferation of RASFs was evaluated with CCK-8 reagent in the presence of IL-1β with/without sulforaphane. The expression of MMPs, tissue inhibitor of metalloproteinase-1, COXs, intracellular mitogen-activated protein kinase signalings, including p-ERK, p-p38, p-JNK, and nuclear factor-kappaB (NF-kB), and the production of PGE2 were examined by Western blotting or semi-quantitative RT-PCR and ELISA. Sulforaphane inhibits unstimulated and IL-1β-induced proliferation of RASFs; the expression of MMP-1, MMP-3, and COX-2 mRNA and protein; and the PGE2 production induced by IL-1β. Sulforaphane also inhibits the phosphorylation of ERK-1/2, p-38, and JNK and activation of NF-kB by IL-1β. These results indicate that sulforaphane inhibits the proliferation of synovial fibroblasts, the expression of MMPs and COX-2, and the production of PGE2, which are involved in synovitis and destruction of RA, and suggest that sulforaphane might be a new therapeutic agent for RA.     

Syntheses of Prostaglandin E2 and E-Cadherin and Gene Expression of β-defensin-2 by Human Gingival Epithelial Cells in Response to Actinobacillus actinomycetemcomitans

The interaction between epithelial cells and microorganisms is the most important step in bacterial infections. Actinobacillus actinomycetemcomitans was suggested to play a significant role in the initiation of periodontitis because of its bacteriological characteristics. Prostaglandins (PG) mediate the inflammatory response. Human beta-defensin-2 (hBD-2) is an antimicrobial peptide and contributes to innate immunity. E-cadherin is responsible for an epithelial intercellular junction. In this study, we investigated the syntheses of PGE2 and E-cadherin and the expression of hBD-2 in human gingival epithelial cells (HGEC) following exposure to A. actinomycetemcomitans. The levels of PGE2 and cyclooxygenase-2, which are responsible for an increase in PGE2, were increased depending on bacteria exposure time. hBD-2 mRNA was induced by A. actinomycetemcomitans, while HGEC exposed to A. actinomycetemcomitans showed a decrease in E-cadherin levels. Etodolac, a selective cyclooxygenase-2 inhibitor reinforced the increase in hBD-2 mRNA levels by A. actinomycetemcomitans. Furthermore, the etodolac suppressed the decrease in E-cadherin levels. Thus, endogenous PGE2 is involved in the hBD-2 and E-cadherin responses of HGEC to A. actinomycetemcomitans. These findings suggest that the inflammatory and antimicrobial response of gingival epithelial cells to A. actinomycetemcomitans is involved in the initiation of periodontal inflammation. A. actinomycetemcomitans may destroy the mechanical epithelial barrier by destroying E-cadherin.     

Preparation of ChIL-2 and IBDV VP2 Fusion Protein by Baculovirus Expression System

This study aims to produce an effective subunit vaccine against infectious bursal disease virus (IBDV).The genes ofchicken interleukin-2 (ChIL-2) and IBDV viral protein 2 (VP2) were amplified and fused by splice overlapextension-polymerase chain reaction (SOE-PCR).The fusion gene was digested by EcoR I/Kpn I and inserted intopBacPAK8 vector,resulting in recombinant transfer plasmid pBacPakVP2-IL2.The recombinant plasmid wastransfected into Sf-9 cells accompanied with hybrid nuclear polyhedrosis virus (HyNPV) genome DNA andlipofectin.Plaque-purification indicated that we had got the recombinant Hy-VP2-IL2.Fusion protein VP2-IL2was expressed effectively both in insect cells and bombyx mori.The expression of fusion protein was confirmed byELISA,SDS-PAGE and Western blotting assay,respectively.This efficient system allows us to meet the need forinexpensive vaccines required by the poultry industry.Cellular & Molecular Immunology.2005;2(3):231-235.