Vesicourachal diverticulum.

We report a rare complication involving a healthy 45-year-old male patient who underwent an emergency laparoscopic appendicectomy for acute perforated gangrenous appendicitis. The patient was catheterised pre- procedure and the ports were inserted under vision. Upon completion of the procedure, a 15 Fr Robinson drain was left in the pelvis and was fed through the suprapubic port hole. Postoperatively the patient developed worsening, generalised abdominal pain and high output from the drain. The patient was re-catheterised but the computed tomography (CT) cystogram did not show any injury to the bladder. The drain fluid creatinine was noted to be raised (>4,000), indicating that urine was leaking into the drain. Conventional cystogram confirmed a contrast leak from the dome around the drain. Flexible cystoscopy confirmed that the drain had transversed the vesicourachal diverticula. The drain was pulled back and converted to a suprapubic catheter with the patient subsequently being discharged. Vesicourachal diverticula is a rare and often asymptomatic anomaly. When undertaking laparoscopic surgery, precautions should be taken to prevent port site injury such as catheterising the patient to ensure the bladder is empty and inserting the ports under direct vision. It is safer to visualise muscle rather than peritoneum during port insertion. In this case, the bladder diverticula was noticed extraperitoneally. Though the indirect CT cystogram reported no injury, this was unreliable as the bladder was not distended which led to the subtle injury being missed. Traditional cystogram should be considered in cases with a negative CT cystogram and a strong suspicion of bladder injury.

Identification and characterization of DC-SIGN-binding glycoproteins in allergenic foods.

BACKGROUND: DC-SIGN (dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin) is a C-type lectin receptor expressed on macrophages and dendritic cells. DC-SIGN has high affinity for fucosylated glycans in several plant glycoproteins and pathogens. DC-SIGN is thought to be crucial for the development of allergic sensitization. However, the precise role of DC-SIGN in food allergy pathogenesis is not yet understood. OBJECTIVE: We sought to characterize DC-SIGN-binding glycoproteins in a panel of allergenic and non-allergenic foods. METHODS: Fluorescent-labeled peanut and soy extracts were used to test protein binding to human monocyte-derived dendritic cells (DCs) by flow cytometry. DC-SIGN-blocking assays were performed by incubating DCs with food extracts followed by staining with anti-DC-SIGN antibody. Using a DC-SIGN-Fc chimera, food extracts were tested for binding by ELISA and autoradiography. IgE immunoblotting was performed with pooled sera from food-allergic subjects. DC activation and maturation were assessed by flow cytometry. RESULTS AND CONCLUSIONS: We demonstrate that peanut agglutinin, a minor peanut allergen, is a novel ligand for DC-SIGN. Peanut agglutinin activates DCs to induce the expression of costimulatory molecules in vitro. We present a comprehensive report on the characterization of DC-SIGN-binding proteins in common allergenic foods such as peanut, soy, tree nuts, egg, and milk. Foods that rarely induce allergy, such as pine nuts, chickpea, and corn, showed no binding to DC-SIGN. Several DC-SIGN-binding proteins show reactivity in serum IgE immunoblots. We have also identified novel non-IgE-binding proteins that interact with DC-SIGN; these proteins may be important for regulating immune responses to these foods.

In silico prediction of Ara h 2 T cell epitopes in peanut-allergic children.

BACKGROUND: Despite the frequency and severity of peanut allergy, the only approved treatment is strict avoidance. Different types of immunotherapy with crude peanut extract are not universally effective and have been associated with relatively high adverse reaction rates. OBJECTIVE: We sought to determine whether in silico predictive algorithms were useful in identifying candidate peptides for an Ara h 2 peptide-based vaccine using peanut-allergic patients' peripheral blood mononuclear cells (PBMCs) in vitro. A human leucocyte antigen (HLA) distribution analysis was also performed. METHODS: Major histocompatibility complex (MHC)-class II-binding peptides were predicted using NetMHCIIpan-2.0 and NetMHCII-2.2 algorithms. PBMCs from 80 peanut-allergic patients were stimulated with overlapping 20-mer Ara h 2 peptides. Cell supernatant cytokine profiles were evaluated by multiplex assays. HLA-DRB1* and HLA-DQB1* typing were performed. RESULTS: Four regions of overlapping sequences induced PBMC proliferation and predominant Th2 cytokine production. HLA genotyping showed 30 different DRB1* allele specificities and eight DQ serological specificities. The in silico analysis revealed similar relevant regions and predicted identical or similar core 9-mer epitopes to those identified in vitro. If relevant peptides, as determined by either in vitro or in silico analysis (15 peptides and 9 core epitopes respectively), were used in a peptide-based vaccine, they would cover virtually all subjects in the cohort studied. CONCLUSIONS AND CLINICAL RELEVANCE: Four dominant regions in Ara h 2 have been identified, containing sequences that could serve as potential candidates for peptide-based immunotherapy. MHC-class II-based T cell epitope prediction algorithms for HLA-DR and -DQ loci accurately predicted Ara h 2 T cell epitopes in peanut-allergic subjects, suggesting their potential utility in a peptide-based vaccine design for food allergy.

Reduction of soluble complement receptor 2/CD21 in systemic lupus erythomatosus and Sjogren's syndrome but not juvenile arthritis.

A soluble form of the complement receptor CD21 (sCD21) is shed from the lymphocyte surface. The amount of sCD21 in serum may modulate immunity as sCD21 levels are correlated with several clinical conditions. We report here the serum levels of sCD21 in juvenile arthritis (JA), systemic lupus erythematosus (SLE) and Sjogren's syndrome (SS). Using enzyme-linked immunosorbent assay, we determined sCD21 levels in SLE, SS and JA patients. Mann-Whitney test for nonparametric two-tail P value was performed to obtain statistical significance. Cytometrical analysis of synovial fluid leucocytes of JA patients was done on a FACSsort. While sCD21 levels in SLE and SS are reduced to levels previously found in rheumatoid arthritis (RA), JA sCD21 levels were normal. sCD21 levels did not correlate with clinical parameters and immunophenotype of synovial cells. CD4 T cells in the synovium were almost all of the CD45RO memory type and 13 of 40 patients displayed synovial expansion of gammadeltaT cells. CD21 shedding in JA differs from RA/SS/SLE. JA sCD21 levels in synovial fluid are always lower compared to blood levels of the same patients. Analysis of JA synovial T cells indicates a T-cell driven response.

Decreased levels of serum soluble complement receptor-II (CR2/CD21) in patients with rheumatoid arthritis.

OBJECTIVE: The soluble cluster of differentiation 21 (sCD21) represents the extracellular portion of the CD21 glycoprotein and is released by shedding from cell surfaces into plasma. Soluble CD21 binds complement fragments and activates monocytes through binding to membrane CD23. Elevated levels of sCD21 are found during Epstein-Barr virus EBV infections, B-cell lymphoma and other lymphoblastoid tumours. The present study was undertaken to investigate levels of sCD21 in rheumatoid arthritis. METHODS: A specific enzyme-linked immunoassay was developed using sCD21, biochemically purified to homogeneity from human plasma as a standard for the determination of sCD21 concentration in patient sera. Peripheral blood B and T lymphocytes were isolated from healthy donors and rheumatoid arthritis patients and cultured, and supernatants were analysed for CD21 shedding. RESULTS: The normal values of serum sCD21 in healthy individuals between 20 and 40 yr of age ranged from 100 to 477 ng/ml (median 292 ng/ml), decreasing with age but not differing with gender. In rheumatoid arthritis patients, sCD21 levels ranged from 50 to 300 ng/ml (median 182 ng/ml), did not differ with age and were independent of rheumatoid factor. CONCLUSIONS: In contrast to healthy donors, patients with rheumatoid arthritis have significantly lower sCD21 levels (P < 0.0001), independently of the age of the patients. Sorted B cells from rheumatoid arthritis patients released amounts of CD21 comparable with those of normal controls. Possible causes and consequences of the findings are discussed.