Bladder-Drained Pancreas Transplantation: Urothelial Innate Defenses and Urinary Track Infection Susceptibility.

BACKGROUND: Pancreas transplantation restores insulin secretion in type 1 diabetes mellitus. The graft also produces exocrine secretions that can be drained enterically (enteric drainage [ED]) or via the bladder (bladder drainage [BD]). We suggest that in BD transplants, such secretions destroy bladder innate immunity, specifically host defense peptides/proteins (HDPs), which increases patient susceptibility to recurrent urinary tract infections (rUTIs). MATERIALS AND METHODS: BD and ED patient records were reviewed retrospectively for UTIs. Urine samples from ED and BD transplant recipients were analyzed for pH, the HDPs ß-defensin 2 (HBD2) and lipocalin-2, and amylase concentrations. In vitro, bacterial growth curves and antimicrobial assays were used to evaluate the effects of pH, HBD2, and HBD2 + pancreatic digestive enzymes (pancreatin) on uropathogenic Escherichia coli (UPEC) survival and growth. RESULTS: Urinalysis revealed a significant difference in pH between the BD and ED cohorts (7.2 ± 0.8 versus 6.7 ± 0.8; P = 0.012). Urinary HDPs were measured and BD, but not ED, lipocalin-2 concentrations were significantly decreased compared with those of diabetics awaiting transplant (P < 0.05). In vitro, an alkaline environment, pH 8.0, concomitant with the urine of the patient who underwent BD transplantation, significantly reduced UPEC growth (P < 0.05); addition of pancreatin to the growth medium was associated with a significant increase (P < 0.001) in growth rate. Antimicrobial data suggested significant UPEC killing in the presence of HBD2 (P < 0.01), but not in the presence of HBD2 + pancreatin (>12,500 amylase units). CONCLUSIONS: These in vivo and in vitro data suggest that BD pancreatic exocrine secretions inactivate the bladder innate defenses, which facilitate UPEC growth and underpins the increased susceptibility of patients who underwent BD pancreas transplantation to rUTIs.

Topical Estrogen Treatment Augments the Vaginal Response to Escherichia coli Flagellin.

The female climacteric or menopausal process characterised by reduced estrogen, associates with an increased risk of recurrent urinary tract infections (rUTIs) linked to uropathogenic Escherichia coli (UPEC). Clinically, topical vaginal estrogen treatment has a prophylactic effect against such infections. The aim of this study was to investigate, in vitro, the effects of a topical estrogen treatment on vaginal epithelial responses following challenge with E.coli flagellin mimicking an UPEC challenge. Immortalised vaginal epithelial cells (VK2 E6/E7), modelling the vaginal epithelium were treated with either 4 nM 17ß-estradiol (E) for seven days, 50 ng/ml E.coli flagellin (F) for 12 h, or 4 nM 17ß-estradiol plus 50 ng/ml flagellin (E + F(12 h)). RNA was analysed by microarray gene profiling using the Illumina HumanHT-12 v 4 Expression Beadchip. Following E + F treatments expression of genes encoding host defence molecules including DEFß4A, DEFB103A, LCN2 as well as those associated with keratinisation eg CNFN and SPRR family genes were significantly enhanced (P < 0.05) compared to either E or F treatments alone. Mutation of estrogen responsive elements (EREs) identified in the DEFß4 gene promoter abolished the augmented gene expression suggesting estrogen functioned directly through a regulatory mechanism involving ESR1/2. Ingenuity pathway analyses also suggested the pro-inflammatory cytokine IL-17A to regulate the vaginal host defences during infection. Pre-treating VK2 E6/E7 cells with estrogen (4 nM) and challenging with 1L-17A & F (12 h) significantly enhanced DEFß4, DEF103A and S100A7 expression (P < 0.05). Origins of vaginal IL-17 in vivo remain unclear, but patient biopsies support γδ T cells located within the vaginal epithelium. These data suggest that the vaginal antimicrobial response induced by flagellin activation of Toll-like Receptor 5 cell signalling is augmented following topical estrogen application.

Maintaining a sterile urinary tract: the role of antimicrobial peptides.

PURPOSE: The normally sterile urinary tract is constantly challenged by microbial invasion leading to a high prevalence of isolated, recurrent and catheter associated urinary tract infection. The continuous emergence of bacterial resistance following overuse of traditional antibiotics requires the urgent development of alternative treatment strategies. The involvement of innate immune mechanisms in host defense is an emerging field of microbiological research with recent work focusing on the urinary tract. We performed a comprehensive literature review to establish the current level of knowledge concerning the role of innate immunity and specifically antimicrobial peptides within the human urinary tract. MATERIALS AND METHODS: A systematic review of the literature was performed by searching PubMed from January 1988 to September 2008. Electronic searches were limited to the English language using the key words antimicrobial, peptide and urinary. Reference lists from relevant reviews were hand searched and appropriate articles were retrieved. The proceedings of conferences held in the last 2 years by the American Urological Association, European Association of Urology and British Association of Urological Surgeons were also searched. RESULTS: Several defensive mechanisms have evolved in response to the threat of urinary infection, comprising physical factors and innate immune responses characterized by the expression of antimicrobial peptides. Antimicrobial peptides are small (less than 10 kDa), cationic and amphipathic peptides of variable length, sequence and structure with broad spectrum killing activity against a wide range of microorganisms including gram-positive and gram-negative bacteria. Several antimicrobial peptides have been identified in the urinary tract, and the amount and type of antimicrobial peptides expressed vary according to tissue source and disease state. These differences may reflect altered levels of innate response and, hence, susceptibility to infection. Antimicrobial peptides are already being exploited therapeutically for skin and endovascular catheter infection, and prospects for useful application in the urinary tract are emerging. CONCLUSIONS: Although investigation of antimicrobial peptide function in the human urinary tract is at an early stage, it is clear that there is considerable potential for the future design of novel therapeutic strategies. More knowledge is needed concerning the pathway of involvement of antimicrobial peptides in the maintenance of urinary tract sterility and the ways in which this is altered during active infection.

The spectrum of prostate cancer care: from curative intent to palliation.

Prostate cancer is one of the most prevalent malignancies affecting men in the developed world. A spectrum of disease states exists and management is tailored to individual patients. Increasing public awareness and prostate-specific antigen testing have led to earlier detection and the possibility of cure but have increased the risk of overtreatment of indolent disease. Advances in curative modalities have reduced side effects and offer patients a choice of treatments. Nonetheless, many need no intervention and may be safely treated with active monitoring. Choice and timing of therapy for locally advanced and recurrent disease are variable, with potential benefits of early intervention counterbalanced by side effects of treatment. Progress has been made in the management of advanced disease; skeletal-related events have been reduced and survival has been increased. This review examines the evidence and rationale behind the treatment options from curative intent to management of locally advanced disease and palliation of metastatic disease.

Targeting Deficiencies in the TLR5 Mediated Vaginal Response to Treat Female Recurrent Urinary Tract Infection.

The identification of the host defence peptides as target effectors in the innate defence of the uro-genital tract creates new translational possibilities for immunomodulatory therapies, specifically vaginal therapies to treat women suffering from rUTI, particularly those carrying the TLR5_C1174T SNP. Urinary tract infections (UTIs) are a microbial disease reported worldwide. Women are particularly susceptible with many suffering debilitating recurrent (r) infections. Treatment is by antibiotics, but such therapy is linked to antibiotic resistance and re-infection. This study explored the innate protective mechanisms of the urogenital tract with the aim of boosting such defences therapeutically. Modelling UTIs in vitro, human vaginal and bladder epithelial cells were challenged with uropathogenic Escherichia coli (CFT073) and microbial PAMPs including flagellin, LPS and peptidoglycan. Flagellin functioning via the TLR5/NFκB pathway was identified as the key UPEC virulence factor causing a significant increase (P < 0.05) in the production of the host-defence peptide (HDP), BD2. BD2-depleted urine samples from bladder infected mice supported increased UPEC growth, strengthening the significance of the HDPs in protecting the urogenital tissues from infection. Clinically, vaginal-douche BD2 concentrations were reduced (p < 0.05) in women suffering rUTIs, compared to age-matched healthy controls with concentrations further decreased (p < 0.05) in a TLR5392Stop SNP rUTI subgroup. Topical vaginal estrogen treatment increased (p < 0.001) BD2 concentrations in all women, including those carrying the SNP. These data identify therapeutic and antibiotic sparing roles for vaginal immunomodulatory agents that specifically target HDP induction, facilitate bacterial killing and disrupt the UPEC infection cycle.

The surgical management and prognosis of renal cell cancer with IVC tumor thrombus: 15-years of experience using a multi-specialty approach at a single UK referral center.

OBJECTIVES: Surgical management of renal cell carcinoma (RCC) invading the inferior vena cava (IVC) remains a technical challenge. However, radical surgery is the only potentially curative treatment. We set out to review our experience of using a multi-specialty approach to these patients over the last 15 years. PATIENTS AND METHODS: Fifty patients with RCC and IVC invasion underwent surgery at our institution (mean age: 59 years). Tumor thrombus was infrahepatic/levels I and II: n = 24, intrahepatic/level III: N = 14, or suprahepatic/level IV: n = 12. Infra- and intrahepatic caval tumors were resected using an abdominal approach and liver transplant techniques without cardiopulmonary bypass (CPB). CPB was used only with level IV thrombus. RESULTS: There were no intraoperative deaths. Median operating time was 6 hours and blood loss 3.5 liters (l). Staging was T3b: n = 34, T3c: n = 10 and T4: n = 6. Median time spent in HDU and hospital were 2 and 12.5 days, respectively. Perioperative mortality was 4%. Metastatic disease (P < 0.001) and level IV thrombus (P < 0.05) were significant negative prognostic factors. Forty of the 50 patients did not have metastasis. With mean follow-up of 38 months, the non-metastatic group had 2-year estimated Kaplan-Meier survival of 82.0% falling to 62.4% at 5 years. Conversely, in the metastatic group, estimated 2-year survival was 26.6% falling to 0% by 5 years. CONCLUSION: Surgical treatment of RCC involving the IVC is possible with acceptable morbidity and mortality. Long-term survival can be expected in over 60% of non-metastatic patients at 5 years. These cases benefit from a multidisciplinary surgical approach. Level III thrombus can be successfully managed without CPB.