High-affinity binding of short peptides to major histocompatibility complex class II molecules by anchor combinations.

We have previously identified four anchor positions in HLA-DRB1*0101-binding peptides, and three anchors involved in peptide binding to DRB1*0401 and DRB1*1101 molecules, by screening of an M13 peptide display library (approximately 20 million independent nonapeptides) for DR-binding activity. In this study, high stringency screening of the M13 library for DRB1*0401 binding has resulted in identification of three further anchor positions. Taken together, a peptide-binding motif has been obtained, in which six of seven positions show enrichment of certain residues. We have demonstrated an additive effect of anchors in two different ways: (i) the addition of more anchors is shown to compensate for progressive truncation of designer peptides; (ii) the incorporation of an increasing number of anchors into 6- or 7-residue-long designer peptides is shown to result in a gradual increase of binding affinity to the level of 13-residue-long high-affinity epitopes. The anchor at relative position 1 seems to be obligatory, in that its substitution abrogates binding completely, whereas the elimination of other anchors results only in partial loss of binding affinity. The spacing between anchors is critical, since their effect is lost by shifting them one position toward the N or C terminus. The information born out of this study has been successfully used to identify DR-binding sequences from natural proteins.     

Intravenous clodronate in the treatment of reflex sympathetic dystrophy syndrome. A randomized, double blind, placebo controlled study

OBJECTIVE: To evaluate the efficacy of intravenous (i.v.) clodronate in patients with reflex sympathetic dystrophy syndrome (RSDS) and to assess the urinary excretion of type I collagen crosslinked N-telopeptide (NTx) before and after the treatment. METHODS: Thirty-two patients with RSDS were randomized to receive either i.v. clodronate 300 mg daily for 10 consecutive days or placebo. Forty days later, the placebo treated patients received the clodronate treatment. Outcome measures included as a primary endpoint the visual analog scale of pain (VAS, range 0-100); secondary endpoints were a clinical global assessment (CGA, range 0-3) and an efficacy verbal score (EVS, range 0-3). Clinical and biochemical assessments were performed before the treatment, 40 (T40), 90 (T90), and 180 (T180) days later. RESULTS: At T40 the 15 patients randomized to clodronate treatment showed significant decreases of VAS and CGA (p = 0.002, p = 0.001, respectively). Compared with the placebo group (17 patients), significant differences were found in all clinical variables (VAS: p = 0.001; CGA: p = 0.001; EVS: p<0.0001). A further clinical improvement was observed throughout the study. Pooling the results of all 32 patients after clodronate treatment, at T180 the overall percentage decrease of VAS was 93.2+/-15.6%, with 30 patients significantly improved or asymptomatic. Significant inverse correlations between baseline NTx values and decreases of VAS were found at T90 (p = 0.03) and T180 (p = 0.01). No adverse events related to treatment occurred. CONCLUSION: A 10 day i.v. clodronate course is better than placebo and effective in the treatment of RSDS. NTx seems to be a predictive factor for clodronate efficacy.     

Drug survival of adalimumab in patients with rheumatoid arthritis over 10 years in the real-world settings: high rate remission together with normal function ability

The purpose of the study was to estimate the clinical profile of naïve biological patients with rheumatoid arthritis (RA) starting adalimumab through 3-year calendar periods and their clinical outcomes such as drug survival and global clinical disease control (GCDC). RA patients starting adalimumab as first biological drug between 2003 and 2012 were subdivided in 3-year calendar periods. Survival on therapy was estimated using the Kaplan-Meier analysis. One and 2-year clinical response was assessed by calculating percentage of patients attaining GCDC (28-joint Disease Activity Score (DAS28) ≤ 2.6 + Health Assessment Questionnaire (HAQ) ≤ 0.5), low disease activity (DAS28 ≤ 3.2), remission (DAS28 ≤ 2.6) and good European League Against Rheumatism (EULAR) response. Multivariate regression models were used to assess baseline predictors of drug discontinuation or achievement of clinical remission. We recruited 1695 RA patients. Overall drug persistence at 3 years was 40.6 %, while the global rate of nonswitching patients was 54.7 %. Compared to 2003–2005, initiators in more recent years had a significantly lower 3-year crude drug retention rate (log rank, p < 0.0001) and a significantly higher rate of switching to alternative biologics (log rank, p < 0.0001). No difference in adverse events or effectiveness rate among the calendar periods was found. A substantial proportion of patients (up to 27 %) achieved GCDC at 2 years, regardless of the calendar period. In real-life setting, RA patients starting adalimumab in more recent years had a higher rate of drug discontinuation not related to ineffectiveness or side effects but to switching, probably due to a wider availability of biologics. A meaningful proportion of patients attained GCDC without any difference across calendar periods.     

Vaccine T-cell epitope selection by a peptide competition assay

The binding of several peptides derived from the Plasmodium falciparum circumsporozoite protein (CS protein) to the human major histocompatibility complex class II proteins HLA-DR5 and -DRw6 was examined in a competition assay. Fixed antigen-presenting cells (APCs) were incubated with various concentrations of each peptide and suboptimal concentrations of stimulator peptides. The binding of the CS peptides to DR5 or DRw6 proteins was then determined in a proliferation assay using two established DR5 or DRw6-restricted T-cell clones with specificity for the stimulator peptides as responder cells. One of five CS peptides, comprising together about 50% of the CS protein sequence, was found to compete with the binding of the stimulator peptides to DR5 and DRw6. The CS peptide CS-(378-398), binding to DR5 and DRw6, was then shown to be able to induce primary in vitro responses of T cells from donors with DR5 and DRw6 haplotypes. CS-(378-398)-induced T-cell clones responded not only to the homologous peptide but also to the native CS protein in the presence of appropriate APCs. The strategy we have applied is of considerable general interest for the engineering of vaccines against any pathogen, since it greatly facilitates the selection of appropriate T-cell epitopes to be incorporated in the vaccine.     

Is conservative treatment really effective for Legg-Calvé-Perthes disease? A critical review of the literature.

INTRODUCTION: The treatment of Legg-Calvé-Perthes Disease (LCPD) is controversial and not well defined. This literature review aimed to assess the quality of the evidence available to support the effectiveness of conservative LCPD treatment advocated by orthopaedic surgeons and(or) paediatricians. A secondary aim was to see if conservative treatments really modify the natural history of LCPD. MATERIALS AND METHODS: The review was performed mainly on the PubMed Database and based on the principles of Evidence Based Practice (EBP). Keywords used were Perthes disease, conservative treatment, containment treatment, review, and weight-relief. EBP is the integration of the best research evidence with clinical expertise and patient values of which there are five different levels of evidence: (1) Randomized Controlled Trials; (2) Prospective Cohort Study; (3) Case Control or Retrospective Cohort Study;(4) Case Series; 5) Expert Opinion or Individual Case Report. Results. Until 20th August 2005 there were 144 articles of clinical relevance about conservative treatment of LCPD: 16.7% of EBP level 5; 50.7% of level 4; 31.9% of level 3; none of level 2; and 0.7% of level 1. CONCLUSION: The quality of evidence that supports conservative treatment for children with LCPD is not of high quality. There is no scientific evidence that conservative treatments modify LCPD natural history. Containment, no containment and simple symptomatic treatment have comparable effectiveness. Prolonged weight-relief and(or) containment treatments are associated with social and psychological problems.