bluuebunny/crossref_metadata_2025 huggingface dataset:
The quantity of naturally processed peptides stably bound by HLA‐A*0201 is significantly reduced in the absence of tapasin
Authors: Barber L.D. , Howarth M. , Bowness P. , Elliott T.
Published: March 2003

Abstract: Tapasin plays a critical role in promoting peptide binding by major histocompatibility complex (MHC) class I molecules in the endoplasmic reticulum. In its absence, cell surface expression of most allotypes is significantly reduced. Two exceptions are HLA‐A*0201 and HLA‐B*2705. In this study, the repertoire of peptides bound endogenously by these allotypes in the absence of tapasin was examined and stability of the HLA class I/peptide complexes assessed. Similar quantities of peptides were recovered from B*2705 complexes expressed in the absence and presence of tapasin and the composition of the peptide pools were not radically different. However, the stability of B*2705 molecules expressed at the surface of tapasin‐deficient cells was found to be reduced which suggests there are subtle changes to the peptide repertoire. The impact of the absence of tapasin was more dramatic for A*0201. Although equivalent levels of cell surface A*0201 are expressed in the presence and absence of tapasin, very little A*0201 glycoprotein was recovered from tapasin‐deficient cells suggesting the complexes readily dissociate. Consistent with reduced stability, A*0201 complexes were found to be rapidly lost from the surface of tapasin‐deficient cells. Analysis of the small quantity of endogenously bound peptides recovered from A*0201 expressed in the absence of tapasin revealed a complex mixture typical of A*0201 molecules expressed in normal cells. Therefore these molecules are unable to exploit the alternative supply of TAP‐independent A*0201‐binding peptides present in the endoplasmic reticulum. Loading of A*0201 with peptides from both TAP‐dependent and TAP‐independent sources is significantly compromised without tapasin.
ANGIOTENSINOGEN AND PLASMINOGEN ACTIVATOR INHIBITOR‐1 GENE POLYMORPHISM IN RELATION TO CHRONIC ALLOGRAFT DYSFUNCTION
Authors: Reis K , Arinsoy T , Derici U , Gonen S , Bicik Z , Soylemezoglu O , Yasavul U , Hasanoglu E , Sindel S
Published: March 2003

Chronic allograft dysfunction (CAD) is the most common cause of allograft failure in the long‐term, and current immunologic strategies have little effect on this condition. The renin‐angiotensin system (RAS) plays important roles in hypertension and progression of chronic renal disease. It is thought that plasminogen activator inhibitor‐1 (PAI‐1) functions in the RAS, in addition to involvement in thrombotic risk and fibrosis. This study investigated possible links between angiotensinogen (AGT) genotypes (M235T/MM, MT, TT) and PAI‐1 genotypes (4G4G, 4G5G, 5G5G) and CAD assessments of both types of polymorphism were performed in 82 renal allograft recipients (47 males and 35 females; mean age 34.87±11.22 years). One hundred healthy subjects (54 males and 46 females; mean age 35.54±10.26 years) were also investigated for AGT polymorphism, and 80 healthy subjects (45 males and 35 females; mean age 36.54±12.41) for PAI‐1 polymorphism. Genotypes were determined using polymerase chain reaction sequence‐specific primers, and polymerase chain reaction followed by restriction fragment length polymorphism analysis.

Kidney recipients with CAD had significantly lower frequencies of the MM genotype and the M allele than those without CAD. (P<0.05 and P<0.001, respectively) Presence of the MT genotype was significantly associated with CAD, and this genotype introduced a 3.5‐fold risk of CAD compared with the MM genotype (P<0.05; 95% confidence interval: 1.21–10.20). The transplant recipients with CAD also had significantly lower frequencies of the 5G/5G genotype and the 5G allele than those without CAD (P<0.001 and P<0.05, respectively). Presence of the 4G allele introduced a 1.94‐fold risk of CAD compared with the 5G allele (95% confidence interval: 1.05–3.66). Determination of AGT M235T and PAI‐1 genotypes before transplantation may help identify patients who are at risk for chronic renal transplant dysfunction.
INFLUENCE OF PARATHYROID HORMONE LEVEL ON RENAL ALLOGRAFT OUTCOME, AND CORRELATION WITH HISTOPATHOLOGICAL FINDINGS
Authors: Özdemir FN , Sezer S , Özdemir BH , Arat Z , Yakupoğlu Ü , Turan M , Haberal M
Published: March 2003

Elevated levels of intact parathyroid hormone (iPTH) are not uncommon after renal transplantation, and this disturbance may affect renal allograft function. This study investigated whether iPTH levels were related to histopathological findings of acute rejection in kidney graft biopsies. Thirty‐eight renal transplant recipients (29 males, nine females; mean age 29.5±10.3years) were studied. Renal allograft biopsy was performed in each case to investigate increased creatinine levels. Lymphocyte and macrophage infiltration of the interstitium was evaluated immunohistochemically with monoclonal antibodies to CD3 and CD68. Expression of HLA‐DR and fibronectin were also studied. The proportion of interstitial cell staining was graded semiquantitatively. Serum calcium, phosphorus and iPTH levels before and after the renal transplantation were compared. Patients were grouped according to their stabilized iPTH levels at 3 months post‐transplantation. Group I (n=13) exhibited persistently elevated iPTH levels (levels elevated since surgery), and Group II (n=25) showed persistently low‐normal iPTH levels. The mean age of the Group I patients was significantly lower, and their serum calcium levels post‐transplantation were significantly higher than those in Group II (P=0.02 and P=0.03, respectively). Persistent elevation of iPTH was strongly associated with interstitial T‐cell density, macrophage density, and glomerular fibronectin expression in the renal allograft biopsies (P<0.05). Also, the time to fibrosis was significantly shorter in Group I (P=0.02). The study revealed that PTH has a potent immunomodulatory effect, and that persistent hyperparathyroidism has a significant impact on renal allograft outcome. The data indicate that the serum iPTH level is a valuable indicator of immune response, and that regular monitoring of serum iPTH levels is essential after renal transplantation.
EFFECT OF BASILIXIMAB ON ACUTE REJECTION IN PEDIATRIC RENAL TRANSPLANTATION: RESULTS FROM TWO CENTERS
Authors: Duzova A , Bakkaloglu M , Dalgic A , Buyan N , Soylemezoglu O , Bakkaloglu A
Published: March 2003

Acute rejection is a major determinant of chronic allograft dysfunction and graft survival. This study evaluated the effect of basiliximab (Simulect®), a 156‐kDa chimeric monoclonal antibody (human and murine) directed against the alpha chain of the interleukin (IL)‐2 receptor of human lymphocytes, on acute rejection in pediatric renal transplantation. Data were collected from two pediatric renal transplantation centers. Forty transplantations (22 males and 18 females; mean age 14.8±3.6 years) were performed between 1996 and 2001. Twelve of the grafts came from cadaveric donors and 28 from living‐related donors. Twenty‐four of the patients were on hemodialysis, 15 were on peritoneal dialysis, and one case was a pre‐emptive transplantation. All patients were placed on triple‐drug immunosuppression [prednisolone + (azathioprine or mycophenolate mofetil) +(cyclosporine or tacrolimus)]. Basiliximab was also administered in 17 cases. The respective rates of biopsy‐proven acute rejection in the basiliximab group and the standard‐regimen group were 0% vs. 17.4% (P>0.05) at 1 month post‐transplantation; 0% vs. 26.1% (P<0.05) at 3 months; and 0% vs. 26.1% (P<0.05) at 6 months. Thirty and 16 patients had completed 1‐ and 3‐year follow ups, respectively, at the time of writing; the 1‐ and 3‐year graft survival rates were 96% (29/30) and 81% (13/16), respectively.

Basiliximab significantly reduced the rates of acute rejection at 3‐ and 6 months post‐pediatric renal transplantation. It was well tolerated by all patients, and caused no significant adverse effects. The effect of basiliximab on long‐term graft survival and chronic allograft dysfunction deserves further investigation.
RELATIONSHIP BETWEEN ANGIOTENSIN‐CONVERTING ENZYME GENE POLYMORPHISM AND CHRONIC RENAL TRANSPLANT DYSFUNCTION
Authors: Akçay A , Sezer S , Özdemir FN , Ataç FB , Verdi H , Terzioğlu M , Arat Z , Çolak T , Haberal M
Published: March 2003

Chronic allograft dysfunction (CAD) is a complex phenomenon caused by underlying kidney disease and superimposed environmental and genetic factors. We investigated the relationship between polymorphism in the gene encoding for angiotensin‐converting enzyme (ACE) and CAD in renal transplant recipients. The study included 125 patients who underwent transplantation over a 5‐year period. The following information was collected for each case: date of transplantation, age and sex of donor and recipient, donor type, cold ischemia time, number of HLA mismatches, number of acute‐rejection episodes, and laboratory findings at discharge from hospital and annual rechecks. Blood pressure was measured at yearly intervals throughout the follow up. DNA isolated from mononuclear cells in peripheral blood was used as a template for amplification of insertion/deletion (I/D) polymorphism in the ACE gene by polymerase chain reaction. The proportions of patients with the different genotypes were DD=54.4%, ID=33.6%, and II=12%. Chronic allograft dysfunction was detected in 36 (52.9%) of the recipients with DD genotype and 15 (26.3%) of those with ID or II genotypes (P<0.003). Analysis of the major risk factors for CAD showed that the serum creatinine level at the time of hospital discharge, the cadaveric donor type, the ACE DD genotype, and the level of proteinuria at 1 year post‐transplantation were associated with poorer renal function (P<0.05). These findings suggest that the DD variant of ACE I/D gene polymorphism is associated with an increased risk of developing CAD.
EFFECT OF HLA MATCHING AND DONOR‐RECIPIENT BODY WEIGHT RATIO WITH TRANSPLANTS FROM SPOUSES
Authors: Emiroğlu R , Yağmurdur MC , Karakayalı H , Moray G , Arslan G , Bilgin N , Haberal M
Published: March 2003

Our transplantation team performed 1061 kidney transplantations from October 1985 to November 2001. Sixty‐nine of these were interspousal transplantations. In 61 cases the wife donated her kidney to the husband, and in the remaining eight cases the husbands were the donors. The average number of HLA‐A, ‐B, and ‐DR mismatches were 3.5, despite the fact that the HLA matching was better for the transplants performed from the first‐degree relatives (average number of HLA‐A, ‐B, and ‐DR mismatches was 2.1). Ten‐year graft survival rates were 55% for the former and 60% for the latter. HLA ‐A, ‐B, and ‐DR typing showed one antigen mismatch in one patient, two mismatches in nine, three mismatches in 17, four mismatches in 33, and more than four mismatches in eight patients. The mean recipient follow‐up period was 90 months (range: 5–170 months). Mean ratio of donor body weight (DBW) to recipient body weight (RBW) was 0.9±0.1 (0.7–1.2). Median serum creatinin levels and creatinin clearance values were 1.9 mg/dl (1.1–3.6 mg/dl), 58.1 ml/min (25–106 ml/min), respectively. Statistically significant relationship between the DBW/RBW ratio and both the creatinin levels and the creatinin clearance values was observed. Eighteen rejection episodes were observed in the wife‐to‐husband transplantations and two in the husband‐to‐wife group. Ten recipients died in the follow‐up period; the DBW/RBW ratio may have an important role for post‐transplant graft functions. We conclude that although HLA matching is not ideal in these cases, graft spouses offer a good alternative to cadaveric kidneys, which are in critically short supply in Turkey.
INFLUENCE OF SIMVASTATIN IN THE TREATMENT OF HIGHLY SENSITIZED DIALYSIS PATIENTS: LONG‐TERM PRE‐ AND POST‐RENAL TRANSPLANTATION OUTCOMES
Authors: Özdemir FN , Akçay A , Çolak T , Turan M , Gülmüş A , Haberal M
Published: March 2003

The graft survival rates of sensitized kidney recipients have been shown to be lower than those of nonsensitized patients. Therefore, panel reactive antibody (PRA) and cross‐match determination is accepted as mandatory screening for renal transplantation candidates. Our recent previous study showed that simvastatin has a significant immunosuppressive effect in PRA‐positive and/or crossmatch‐positive patients. We present the long‐term pre and post‐transplantation outcomes of simvastatin treatment in highly sensitized dialysis patients. Thirty patients were followed for a mean period of 22 months. The PRA and flow cytometric measurements were performed at monthly intervals. Ten patients underwent successful kidney transplantation (eight living‐related and two cadaveric). None of the patients developed hyperacute or acute rejection, and there was no graft loss during the 16.1±8.2 months of post‐transplantation follow up. Of the 18 patients who stayed on dialysis throughout the study with PRA‐positivity, six were lost to follow up and three spontaneously stopped taking the simvastatin. In the latter three cases, the PRA levels rose significantly after the drug was discontinued. Eight of the remaining nine PRA‐positive patients showed significant drops in mean PRA level over the study period, and entered the range considered acceptable for transplantation. Only one patient showed persistently high PRA levels throughout the study. In one patient, the drug had to be discontinued because of acute toxic hepatitis. In conclusion, the results indicate that long‐term continuous simvastatin therapy is effective in immunized and highly sensitized dialysis patients. Meanwhile, it has a beneficial effect on 1‐year graft survival rates in sensitized renal transplantation patients.
CHRONIC REJECTION: PROSPECTS FOR THERAPEUTIC INTERVENTION IN FIBROPROLIFERATIVE VASCULAR DISEASE
Authors: Häyry P , Aavik E , Sarwal M , Du Toit D , Vamvakopoulos J
Published: March 2003

Vascular disease, manifesting as either transplant arteriopathy or native atherosclerosis, is currently the main obstacle to successful transplant outcome. In addition, vascular restenosis following balloon angioplasty or stenting continues to limit the long‐term efficacy of these procedures. Neointimal hyperplasia is refractory to conventional immunosuppression although newer agents, such as rapamycin, have shown considerable promise in its control. By allowing a large‐scale study of gene expression during vascular remodelling, the emerging field of genomics is poised to revolutionise the drug‐discovery process. Here we summarise our initial experience using genomic methods to identify new targets for therapeutic intervention in vascular disease.
HLA profile of three ethnic groups living in the North‐Western region of Russia
Authors: Evseeva I. , Spurkland A. , Thorsby E. , Smerdel A. , Tranebjaerg L. , Boldyreva M. , Groudakova E. , Gouskova I. , Alexeev L. L.
Published: March 2003

Abstract: HLA class II alleles were determined by PCR‐SSO and PCR‐SSP typing of DNA samples from 55 Nentsy, 81 Saami and 73 Pomor individuals from the North‐European part of Russia. The results were compared with similar data from Russians. A high frequency of the DRB1*04‐DQA1*0301‐DQB1*0302 haplotype and a low frequency of the DRB1*11‐DQA1*0501‐DQB1*0301 haplotype, observed in all three ethnic groups, may indicate a common aboriginal component in their ancestry. Saami and Pomors displayed a similar pattern of allele and haplotype distribution, with the exception of the DRB1*04‐DQA1*0304‐DQB1*0301 haplotype, which was significantly higher among Saami compared Nentsy, Pomors and Russians. Nentsy individuals had a particularly high frequency of the DRB1*09‐DQA1*0301‐DQB1*0303 and the DRB1*12‐DQA1*0501‐DQB1*0301 haplotypes. Genetic distances and correspondence analysis show that Pomors have a close relationship with Norwegians and Finns, whereas Nentsy and Saami are more closely related to Oriental populations.
Eight new HLA‐A alleles associated with antigens in the A2 CREG
Authors: Gans C.P. , Bradshaw D.M. , Jones P.F. , Mitton W. , Koester R. , Ng J. , Hartzman R.J. , Hurley C.K.
Published: March 2003

Abstract: This report describes eight novel HLA‐A alleles. Seven of these new alleles contain substitutions previously reported in other HLA‐A alleles, suggesting an origin resulting from a gene conversion mechanism. Of these seven, A*2431 contains a substitution previously associated with a larger polymorphic motif. A*0247 contains a substitution at a previously polymorphic position, but encodes an amino acid change previously unreported in any HLA‐A, ‐B or ‐C alleles.
Description of a novel HLA‐DRB1 allele, DRB1*1207
Authors: Dunckley H. , Le T. , Dodd R. , Hogbin J.‐P. , Strickland J. , Chapman G. , Greville W.D.
Published: March 2003

Abstract: A new DRB1 allele has been identified during routine HLA‐DRB1 generic typing with sequence specific oligonucleotides. The new allele was confirmed by PCR‐restriction fragment length polymorphism analysis and subsequently sequenced. This showed the novel allele, named HLA‐DRB1*1207, was similar in sequence to DRB1*12011, except for codon 69 of exon 2.
Novel HLA‐DRB3 alleles discovered during routine sequencing based typing, DRB3*02023, DRB3*0212, DRB3*0213 and DRB3*03012
Authors: Greville W. D. , Kennedy A. , Chapman G. , Dunckley H.
Published: March 2003

Abstract: We report the discovery of four HLA‐DRB3 alleles during routine sequencing based typing (SBT); DRB3*02023, DRB3*0212, DRB3*0213 and DRB3*03012. These alleles differ from other HLA‐DRB3 alleles by previously undescribed single nucleotide polymorphisms.
Characterization of a new HLA‐DRB3 allele, DRB3*0217, by direct sequencing
Authors: Frison S. , Longhi E. , Poli F. , Espadas de Arias A. , Scalamogna M.
Published: March 2003

Abstract: We report the identification of a novel DRB3*02 using sequence‐based typing (SBT). This new allele, officially named DRB3*0217, was detected while performing HLA high resolution typing of a bone marrow recipient and his siblings. DNA sequencing demonstrated the presence of a nucleotide substitution in exon 2 at position 199 where a C was substituted by a T. This point mutation at codon 67 (CTC→TTC) has resulted in an amino acid substitution from Leucine to Phenylalanine.
Enhanced binding of low‐affinity antibodies interacting simultaneously with targeted cell surface molecules and Fc receptor
Authors: Mendez‐Fernandez Y.V. , Pogulis R.P. , Block M.S. , Johnson A.J. , Kuhns S.T. , Allen K.S. , Hansen M.J. , Pease L.R.
Published: March 2003

Abstract: The possibility that different forms of class I molecules might be expressed on the cell surface of lymphocytes has been investigated periodically over the past several decades. A series of major histocompatibility complex (MHC) class I‐specific monoclonal antibodies, including the commonly used antibodies 64‐3‐7 and 25‐D1.16, bind B cells differentially, suggesting the existence of differentially expressed class I‐associated cell surface determinants on B lymphocytes. However, the ability of antibodies to bind cells is determined by the sum of interactions between the antibodies and the molecules expressed on the cell surface. The interactions of class I‐specific antibodies with B cells were dissected, revealing dual specificity of the antibodies for the targeted class I molecules, as well as to Fc receptors preferentially expressed by B cells. We demonstrate that antibodies simultaneously bind targeted class I molecules and Fc receptors expressed on the surface of B cells. Simultaneous binding to two cell surface structures significantly enhances the class I‐specific binding pattern of certain antibodies by increasing their avidity, leading to apparent cell‐specific differences in MHC expression patterns. We conclude that no differences in MHC structures need be postulated to account for the observed binding patterns.
Identification of HLA‐A*0249 and confirmation of A*2615
Authors: Voorter C.E.M. , Gervais T. , Van Den Berg‐Loonen E.M.
Published: March 2003

Abstract: A new HLA‐A*02 allele, A*0249, and the confirmatory sequence of A*2615 are here reported. Both alleles were detected by irregular patterns during routine molecular typing. A*0249 showed two mismatches with A*02011 in exon 3 at positions 538 and 539, changing amino acid 156 from leucine to arginine. Remarkable was a mismatch in exon 4, at position 779, where the C of A*0201 was changed to A in A*0249. As A*0209 has the same substitution, A*0249 may have arisen from A*0209. The A*2615 allele was identical to A*2601 in exons 2 and 3 except for a single nucleotide difference at nucleotide position 180, changing codon 36 from phenylalanine to leucine. This is a unique amino acid change, as in all the class I alleles a phenylalanine was identified at this position.
Extending the concept of template‐assembled synthetic proteins
Authors: Tuchscherer G. , Grell D. , Mathieu M. , Mutter M.
Published: March 2003

Abstract: The creation of native‐like macromolecules in copying nature’s way represents a fascinating challenge in protein chemistry today. In the absence of a detailed knowledge of the complex folding pathway the ultimate goal in protein de novo design, the construction of artificial proteins with predetermined three‐dimensional structure and tailor‐made functions based on a defined, generally valid set of rules, appears to be still out of reach. With progress in synthesis strategies and biostructural characterization methods, topological templates have become a versatile tool for inducing and stabilizing secondary and tertiary structures, such as protein loops, β‐turns, α‐helices, β‐sheets and a variety of folding motifs. In this article, we extend the concept of template‐assembled synthetic proteins for the construction of protein‐like topologies with multiply bridged, oligocyclic chain architectures termed locked‐in tertiary folds that exhibit unique physicochemical and folding properties because of the highly confined conformational space. Furthermore, we show that some fundamental questions in protein assembly can be approached applying the template concept. Using covalent template trapping of self‐associated peptide assemblies in aqueous solution the structural and physical forces guiding protein folding, supramolecular assembly and molecular recognition processes can be studied on a molecular level.
Ion channel activation by SPC3, a peptide derived from the HIV‐1 gp120 V3 loop
Authors: Carlier E. , De Waard M. , Mabrouk K. , Fajloun Z. , Rochat H. , Sabatier J. ‐M. , Moulard M.
Published: March 2003

Abstract: SPC3 is a multibranched peptide containing eight identical GPGRAF motifs which are derived from the human immunodeficiency virus (HIV)‐1 gp120 V3 loop consensus sequence. This molecule was reported to prevent the infection of CD4+ cells by various HIV‐1 and HIV‐2 strains. However, the molecular mode of action of SPC3 remains unclear. Here, we investigated the possibility that SPC3 could interact with α/β‐chemokine receptors following observations that, first, the V3 loop is likely to be involved in α/β‐chemokine receptor‐dependent HIV entry and, second, natural ligands of these receptors are potent inhibitors of cell infection. To address this point, we examined the effects of SPC3 on Xenopus oocytes either uninjected or expressing exogenous human CXCR4 α‐chemokine receptors. Extracellular applications of micromolar concentrations of SPC3 onto Xenopus oocytes trigger potent inward chloride currents which can be inhibited by increasing extracellular Ca2+ concentration. This effect can be blocked by chloride channel antagonists and is highly specific to SPC3 as it is not triggered by structural analogs of SPC3. The SPC3‐induced chloride conductance in oocytes is α/β‐chemokine receptor dependent because: (i) SPC3 alters the sensitivity of this channel to external applications of human recombinant MIP‐1α, a natural ligand of human CCR5 receptor, and (ii) the amplitude of the inward current could be increased by the expression of exogenous human CXCR4 chemokine receptor. The effect of SPC3 appears to rely on the activation of a phospholipase A2 signaling pathway, but is not affected by changes in cytosolic Ca2+ concentration, or by alterations in Gi/Go protein, adenylate cyclase, phospholipase C or protein kinase C activity. Altogether, the data indicate that SPC3 is capable of activating a surface α/β‐chemokine‐like receptor‐mediated signaling pathway in competent cells, thereby triggering, either directly or indirectly, a Ca2+‐inactivated chloride conductance.
Isopeptide bonds in chemotactic tripeptides. Synthesis and activity of lysine‐containing fMLF analogs
Authors: Pagani Zecchini G. , Nalli M. , Mollica A. , Lucente G. , Paglialunga Paradisi M. , Spisani S.
Published: March 2003

Abstract: In order to explore the properties of chemotactic N‐formylpeptides containing isopeptide bonds within their backbones, a group of lysine‐containing analogs of the prototypical chemotactic tripeptide N‐formylmethionyl‐leucyl‐phenylalanine (fMLF) was synthesized. The new analogs were designed by adding to the HCO‐Met or Boc‐Met residue a dipeptide fragment made up of Lys and Phe residues joined through Lys Nα or Nε bonds, in all possible combinations. Thus, the following six pairs of tripeptides were synthesized and examined for their bioactivity: RCO‐Met‐Lys(Z)‐Phe‐OMe (2a, b), RCO‐Met‐Lys(Z‐Phe)‐OMe (3a, b), Z‐Lys(RCO‐Met)‐Phe‐OMe (4a, b), Z‐Phe‐Lys(RCO‐Met)‐OMe (5a, b), RCO‐Met‐Phe‐Lys(Z)‐OMe (6a, b) and Z‐Lys(RCO‐Met‐Phe)‐OMe (7a, b), with R=OC(CH3)3 and R=H for compounds a and b, respectively. All the new models were characterized fully and their activity (chemotaxis, superoxide anion production and lysozyme release) on human neutrophils determined as agonists (compounds b) and antagonists (compounds a). All N‐formyl derivatives 2b−7b are less potent than fMLF‐OMe as chemoattractants, but compound 7b exhibits selective activity as superoxide anion producer. Derivatives 2a−7a do not show antagonistic activity towards fMLF induced chemotaxis and O2− production, however, all these compounds except 4a antagonize lysozyme release by 60%.
Mutational analysis of a blood coagulation factor VIII‐binding peptide
Authors: Pflegerl K. , Hahn R. , Berger E. , Jungbauer A.
Published: March 2003

Abstract: A peptide screened from a combinatorial peptide library with the sequence EYKSWEYC performed best as a ligand for affinity chromatography of human blood coagulation factor VIII (FVIII). With this peptide immobilized on monolithic CIM columns via epoxy groups we were able to capture FVIII from diluted plasma. Rational substitution of amino acids by spot synthesis revealed that lysine and cysteine can be exchanged for almost all other proteinogenic amino acids without loss of affinity to FVIII. This offers the possibility of site‐specific attachment via either one of these residues or the N‐ or C‐terminus. The aliphatic positions O5(tryptophan) and O7(tyrosine), together with the charged position O6(glutamic acid), seem to form the core of the binding unit. In the positions with aliphatic amino acids, substitution by tyrosine or phenylalanine, and in the positions with charged amino acids, substitution by aspartic acid or lysine, preserved the affinity to FVIII. The functionality of the selected peptides was confirmed by affinity chromatography. Selective binding and elution could be achieved.
Identical clonal types of Porphyromonas gingivalis or Prevotella nigrescens recovered from infected root canals and subgingival plaque
Authors: Gonçalves R. B. , Robitaille M. , Mouton C.
Published: March 2003

Clinical samples from 10 infected root canals and from subgingival plaque in 10 patients were screened by anaerobic culture for black‐pigmented anaerobes. A total of 17 Porphyromonas gingivalis and 9 Prevotella nigrescens were obtained from four patients and were identified by species‐specific polymerase chain reaction (PCR) amplification. The arbitrarily primed PCR reaction used to examine the genetic diversity of the isolates revealed that the P. gingivalis or P. nigrescens simultaneously present in the root canal system and in subgingival plaque of all four patients were genotypically indistinguishable. These data indicate that the endodontium and the periodontium can be colonized by the same clonal types of black‐pigmented anaerobes.
Protective effect of serum antibodies against a 110‐kilodalton protein of Actinobacillus actinomycetemcomitans following periodontal therapy
Authors: Beikler T. , Karch H. , Ehmke B. , Klaiber B. , Flemmig T. F.
Published: March 2003

Thirty‐four adult patients with untreated periodontitis were randomly assigned to receive full mouth scaling alone or scaling with an adjunctive antimicrobial therapy, both followed by supportive periodontal therapy. At 24 months, specific serum immunoglobulin A (IgA), IgG and IgG subclass antibody reactivities against a 110‐kDa protein of Actinobacillus actinomycetemcomitans were assessed by Western blot. In patients harboring A. actinomycetemcomitans intraorally, the IgG4 antibody reactivity against the 110‐kDa protein of A. actinomycetemcomitans was associated with significantly increased survival rates of teeth and of sites not exhibiting 2 mm or more of probing attachment loss. The same trend was found for IgG3 and IgG2 antibody reactivities, but it was statistically insignificant. No association with clinical treatment outcome was observed for IgA, IgG and IgG1 antibody reactivities. The results indicated that systemic IgG4 antibody reactivity against the 110‐kDa protein of A. actinomycetemcomitans may have a protective effect against periodontal disease progression in patients harboring A. actinomycetemcomitans andreceiving periodontal therapy.
Salivary immunoglobulin A production against a synthetic oligopeptide antigen of Actinobacillus actinomycetemcomitans fimbriae
Authors: Honma K. , Kato T. , Okuda K.
Published: March 2003

Actinobacillus actinomycetemcomitans is an important pathogen in human periodontal diseases. We attempted to produce effective antibodies against A. actinomycetemcomitans fimbrial antigen, which was shown to be an attachment factor. An oligopeptide based on the amino acid sequence of A. actinomycetemcomitans fimbriae was synthesized and conjugated with branched lysine polymer resin beads. Mice were immunized with the synthetic antigen together with one or more of Freund’s incomplete adjuvant, the Ribi adjuvant system, liposomes, mouse interleukin 4 expression plasmids, and cholera toxin. After immunization, salivary immunoglobulin A (IgA) and serum IgG levels against the synthetic oligopeptide antigen were determined by enzyme‐linked immunosorbent assay. The serum IgG responses against the fimbrial antigen were significantly higher in animals immunized intramuscularly with the Ribi adjuvant system. A high salivary IgA response to the fimbriae was induced by intranasal mucosal immunization with cholera toxin and mouse interleukin 4 expression plasmids.
Apoptosis in Porphyromonas gingivalis–specific T‐cell lines
Authors: Gemmell E. , Prajaneh S. , Grieco D. A. , Taylor J. J. , Seymour G. J.
Published: March 2003

Fluorescence‐activated cell sorter analysis and transmission electron microscopy were used to determine the presence of apoptotic cells in Porphyromonas gingivalis–specific T‐cell lines established from the peripheral blood of 10 P. gingivalis–infected individuals. P. gingivalis outer membrane antigens were presented to the T cells by autologous Epstein‐Barr virus–transformed B cells for 6, 24, 48 and 72 h. Transmission electron microscopy demonstrated the presence of typical apoptotic cells in all cultures. Annexin V–positive cells were present at low concentrations at all 4 four periods. A mean of approximately 2–3% of the CD4 cells and 1–3.5% of the CD8 cells were annexin V–positive, with an increase to around 5.5% positive CD4 cells at 6 h in wells containing P. gingivalis compared with cultures not containing antigen. This difference was not, however, significant at the 0.05 level (P=0.073). The mean (±standard error) CD4:CD8 ratios of the T‐cell lines when first established using peripheral blood mononuclear cells as antigen‐presenting cells was significantly higher (5.2±1.1) than when transformed B cells were used as antigen‐presenting cell (1.2±0.5). While this study has shown apoptosis occurring in the T‐cell lines, it has not shown definitively that the reversion in the CD4:CD8 ratio in the P. gingivalis–specific T cells following antigen presentation by autologous Epstein‐Barr virus–transformed B cells is due to apoptosis of a CD4 population. Alternatively, the reversion in the CD4:CD8 ratio could be due to a selective proliferation of the CD8 population which, in turn, could be relevant to the immunopathology of periodontal disease induced by P. gingivalis.
Unaltered expression of the major protease genes in a non‐virulent recA‐defective mutant of Porphyromonas gingivalis W83
Authors: Abaibou H. , Ma Q. , Olango G. J. , Potempa J. , Travis J. , Fletcher H. M.
Published: March 2003

Porphyromonas gingivalis FLL32, a recA mutant, was isolated during construction of a recA defective mutant of P. gingivalis W83 by allelic exchange mutagenesis. In contrast to W83 and FLL33, the typical recA− mutant previously reported, FLL32 was non‐pigmented, lacked β‐hemolytic activity on blood agar and produced significantly less proteolytic activity. The proteolytic activity in FLL32 was mostly soluble. Expression of the rgpA, rgpB and kgp protease genes was unaltered in FLL32 when compared to FLL33 and the wild‐type strain. FLL32 exhibited reduced virulence in a murine model and partially protected the animals immunized with that strain against a subsequent lethal challenge by the wild‐type strain. These results indicate that the reduced level of proteolytic activity in FLL32 may be due to a defect in the processing of the proteases. Further, immunization with a non‐virulent recA defective mutant of P. gingivalis can partially protect against a lethal wild‐type challenge. The results from this study suggest that the recA locus may be involved in expression and regulation of proteolytic activity in P. gingivalis.
Differential in situ distribution of interleukin‐8, monocyte chemoattractant protein‐1 and Rantes in human chronic periapical granuloma
Authors: Marton I. J. , Rot A. , Schwarzinger E. , Szakáll S. , Radics T. , Vályi‐Nagy I. , Kiss C.
Published: March 2003

In situ distribution of three prototype chemokines interleukin (IL)‐8, monocyte chemoattractant protein (MCP)‐1 and Rantes was determined in chronic human periapical granulomas by immunohistochemistry using monoclonal antibodies. IL‐8 was found primarily in the cytoplasm of the Malassez epithelial cells. MCP‐1 immunoreactivity was confined to the endothelial cells that lined small venules. Each of the three investigated chemokines, including Rantes, exhibited a characteristic binding pattern to the extracellular matrix of the lesion. The observed chemokines may play a role in establishing the cellular composition of chronic apical periodontitis, thus augmenting the intensity of local inflammation and tissue damage.
Adhesion of Candida albicans, but not Candida krusei, to salivary statherin and mimicking host molecules
Authors: Johansson I. , Bratt P. , Hay D. I. , Schluckebier S. , Strömberg N.
Published: March 2003

The aim of the present study was to identify salivary molecules affecting adhesion of Candida albicans and Candida krusei to salivary pellicles and epithelial cells. Strains of C. albicans (GDH18, GDH3339, CA1957, ATCC 28366 and ATCC 10321), but not C. krusei (strains ATCC 14243 and Ck9), bound to saliva‐coated hydroxyapatite and buccal epithelial cells. Parotid saliva fractions containing statherin, glycosylated proline‐rich proteins (PRP) and as yet unidentified components mediated adhesion of strain GDH18; Fucα1‐2Galβ1‐4Glc partly inhibited the adhesion to those fractions not containing statherin. Pure statherin, but not PRP‐1, mediated dose‐dependent adhesion of C. albicans strain GDH18 to hydroxyapatite beads. Candida isolates (GDH18, GDH3339 and CA1957) bound somewhat more avidly to statherin/saliva relative to ATCC strains 28366 and 10321, while the opposite was true for adhesion to buccal epithelial cells. Adhesion of C. albicans strain GDH18 to saliva‐coated hydroxyapatite and buccal epithelial cells was completely (93%) and partly (43%) blocked by statherin‐specific immunoglobulin G (IgG) antibodies, respectively. Control IgG antibodies did not block Candida adhesion. Blockage of Candida adhesion to epithelial cells also occurred with Fucα1‐2Galβ1‐4Glc (49%) and N‐acetylglucosamine (38%), while statherin specific IgG antibodies in combination with Fucα1‐2Galβ1‐4Glc almost completely eliminated Candida adhesion (79%). In addition, statherin in solution blocked the adhesion of strain GDH18 to epithelial cells by inducing aggregation of Candida cells.
Long‐term persistence and recall of immune responses in aged mice after mucosal immunization
Authors: Harrod T. , Martin M. , Russell M. W.
Published: March 2003

To evaluate the retention of memory in the mucosal immune system of aged animals, 2‐year‐old mice that had been immunized intragastrically at 3 months of age with Streptococcus mutans protein AgI/II coupled to the B subunit of cholera toxin (CTB) were evaluated by ELISA for antibodies to AgI/II and CT in serum, saliva, and vaginal wash. To evaluate recall responses, mice were then immunized intragastrically with AgI/II‐CTB, in comparison with previously unimmunized controls. Those that had been primed in their youth showed a more rapid antibody response in serum (immunoglobulin G (IgG)) and secretions (IgA), but all animals eventually responded to a similar degree after the third dose. Mice immunized at 3 months also retained for 2 years spleen cells capable of proliferating in vitro in response to AgI/II. These data show that aged mice retain the ability to mount immune responses to mucosally presented immunogens and that memory to mucosally presented immunogens can persist for almost the whole lifetime of a mouse.
The recA gene in Porphyromonas gingivalis is expressed during infection of the murine host
Authors: Liu Y. , Fletcher H. M.
Published: March 2003

The recA gene in Porphyromonas gingivalis is involved in DNA repair. To further elucidate the importance of the recA locus in the pathogenesis of P. gingivalis, we assessed its ability for expression in an animal host. The promoterless xa‐tetA(Q)2 cassette was used in heterodiploid mutants to study recA promoter activity during infection. P. gingivalis FLL118.1 had the xa‐tetA(Q)2 cassette under the control of recA promoter whereas P. gingivalis FLL119 had the cassette in the opposite orientation. xa encodes a bifunctional xylosidase/arabinosidase enzyme (XA) and the tetA(Q)2 gene product confers tetracycline resistance. Intramuscular infection in a mouse model allowed the recovery of the bacteria from inguinal lymph nodes. Infusion of tetracycline in the animals permitted the enrichment P. gingivalis FLL118.1 over the wild‐type strain, during a mixed infection. The xylosidase activity of FLL118.1 could be detected on agar plates in the presence of 5‐methylumbellifiry‐β‐d‐xyloside. No such enrichment for xylosidase activity was detected when the mixture of P. gingivalis W83 and P. gingivalis FLL119 was used to infect the mouse or cultured in vitro. These results indicated that recA promoter was transcriptionally active during the infection of the murine host and further support the importance of this locus during the P. gingivalis infection process.
Porphyromonas gingivalis antigen preferentially stimulates T cells to express IL‐17 but not receptor activator of NF‐κB ligand in vitro
Authors: Oda T. , Yoshie H. , Yamazaki K.
Published: March 2003

Although T cells have been implicated in the pathogenesis and are considered to be central to both their progression and control of chronic inflammatory periodontal diseases, the precise contribution of T cells to tissue destruction has not been fully clarified. Recently, interleukin (IL)‐17 and receptor activator of Nuclear factor κB NF‐κB ligand (RANKL) have received much attention as a result of their proinflammatory and bone metabolic roles, respectively. We therefore investigated the effect of outer membrane protein (OMP) from Porphyromonas gingivalis (P. gingivalis) on the expression of IL‐17 and RANKL in peripheral blood mononuclear cells (PBMCs) and compared these between gingivitis and periodontitis, which are representative of stable and progressive lesions, respectively. The in situ expression of these molecules was also examined. P. gingivalis OMP stimulated PBMCs to express IL‐17 at both the mRNA and protein level. Although the mean expression of mRNA was not different between the two groups, the mean level of IL‐17 in the culture supernatants was higher in gingivitis patients than in periodontitis patients. However, the frequency of IL‐17‐positive samples was higher in the periodontitis patients. This stimulatory effect was not evident for RANKL expression in either periodontitis or gingivitis patients. In gingival tissue samples, IL‐17 mRNA was detected in gingivitis more frequently than in periodontitis. The expression of RANKL mRNA was much lower than that of IL‐17 in terms of both level and frequency. These results suggest that IL‐17 but not RANKL may be involved in the pathogenesis of periodontal diseases. However, there may be negative regulatory mechanisms for IL‐17 in gingivitis.
Migration and atopic disorder in Swedish conscripts
Authors: Hjern Anders , Rasmussen Finn , Johansson Malin , Åberg Nils
Published: March 2003

Hjern A, Rasmussen F, Johansson M, Åberg N. Migration and atopic disorder in Swedish conscripts.

Pediatr Allergy Immunol 1999: 10: 209–215. © Munksgaard, 1999

We have studied asthma and allergic rhinitis prevalence in Swedish conscripts born 1973–1977 according to the military service conscription register in relation to the socio‐economic status and country of birth of the conscripts and their parents, and age when granted residency in Sweden. There was an increase in prevalence of asthma and allergic rhinitis over time in all groups irrespective of country of birth or ethnic origin. Conscripts who themselves were born in Africa, Asia, Latin America and the Mediterranean had a significantly lower risk for asthma and allergic rhinitis than Swedish‐born conscripts. The risk of atopic disorder among the foreign‐born conscripts increased with time of residency in Sweden. Conscripts with mothers from Latin America, Asia and Africa were identified as having the highest risk for atopic disorder among Swedish‐born conscripts with high socio‐economic status; the adjusted risk ratio (RR) for asthma was 2.6 (95% CI 1.7–4.0) and that for allergic rhinitis was 2.0 (1.5–2.6). The conscripts with mothers from the Mediterranean had the lowest risk for atopic disorders of the Swedish‐born conscripts with low socio‐economic status; the RR for asthma was 0.43 (0.34–0.56) and that for allergic rhinitis was 0.84 (0.76–0.93). This study demonstrates that factors related to migration and ethnicity are important determinants of atopic disorder among Swedish conscripts.
Anti‐centromere antibodies as a marker of Raynaud's phenomenon in pediatric rheumatologic diseases
Authors: Hossny Elham , Hady Hala Abdul , Mabrouk Randa
Published: March 2003

To examine the possible relationship between anti‐centromere antibodies (ACA) and pediatric rheumatologic diseases, we investigated the presence of ACA (using enzyme immunoassay) in the sera of 45 children and adolescents with such diseases and compared the results with a group of 42 age‐ and gender‐matched healthy subjects. ACA were present (≥ 10 U/ml) in three out of five patients (60%) with scleroderma (SCD), in seven out of 16 (43.8%) patients with systemic lupus erythematosus (SLE), in two out of five patients (40%) with mixed connective tissue disease (MCTD), in one out of four patients (25%) with dermatomyositis (DMS), and in two out of 14 patients (14.3%) with juvenile rheumatoid arthritis (JRA). ACA were also detected in a single patient with anti‐phospholipid syndrome (APL) who had digital gangrene and hemiparesis, as well as in two healthy subjects. ACA positivity was related to the presence of Raynaud's phenomenon in the studied sample, as 86% of patients suffering from the phenomenon were ACA positive. ACA positivity was associated with older age, high blood pressure and high erythrocyte sedimentation rate (ESR) values, and lower hemoglobin and weight and height percentile values. It was also higher among anti‐nuclear antibody‐positive subjects. Raynaud's phenomenon and ACA positivity shared almost the same clinical and laboratory associations in the studied patients. Thus, ACA are probably among the markers of Raynaud's phenomenon in pediatric rheumatologic diseases. Their value as predictors of future development of the phenomenon needs further evaluation.
Diagnosis of IgE‐mediated food allergy among Swiss children with atopic dermatitis
Authors: Eigenmann Philippe A. , Calza Anne‐marie
Published: March 2003

Diagnosis of food allergy in children with atopic dermatitis (AD) relies on a good knowledge of the prevalence of the disease and of the foods most frequently involved. Our objective was to define these characteristics in a population of Swiss children with AD. Patients referred to a pediatric allergist or a dermatologist for AD were routinely tested by skin‐prick test (SPT) to seven common food allergens (milk, egg, peanut, wheat, soy, fish, and nuts), and to all other foods suspected by history. Patients with positive SPTs were further evaluated for specific serum immunoglobulin E (IgE) antibodies (by using the CAP System FEIA™). CAP values were interpreted following previously published predictive values for clinical reactivity. Patients with inconclusive results (between the 95% negative predictive value [NPV] and the 95% positive predictive value [PPV]) were challenged with the suspected food. A total of 74 children with AD were screened for food allergies. Negative SPTs excluded the diagnosis in 30 subjects. Nineteen patients were diagnosed by histories suggestive of recent anaphylactic reactions to foods and/or CAP values above the 95% PPV. Forty‐three food challenges (35 open challenges and eight double‐blind, placebo‐controlled in children with persistent lesions of AD despite aggressive topical skin treatment) were performed in patients with positive SPTs but with inconclusive CAP values. Six patients were diagnosed as positive to 15 foods. Challenges were not performed to high‐allergenic foods in young children (under 12 months of age for egg and fish, and under 3 years of age for peanuts and nuts). Altogether, 33.8% (25 of 74) of the AD patients were diagnosed with food allergy. The prevalence of food allergy was 27% (seven of 25) in the group referred to the dermatologist for primary care of AD. The foods most frequently incriminated were egg, milk, and peanuts. The prevalence of food allergy in our population was comparable to that in other westernized countries, suggesting an incidence of food allergy in approximately one‐third of children with persistent lesions of AD. Together with milk and eggs, peanuts were most frequently involved in allergic reactions.