SummaryP66, a Borrelia burgdorferi surface protein with porin and integrin-binding activities, is essential for murine infection. The role of P66 integrin-binding activity in B. burgdorferi infection was investigated and found to affect transendothelial migration. The role of integrin binding, specifically, was tested by mutation of two amino acids (D205A,D207A) or deletion of seven amino acids (Del202–208). Neither change affected surface localization or channel-forming activity of P66, but both significantly reduced binding to αvβ3. Integrin-binding deficient B. burgdorferi strains caused disseminated infection in mice at 4 weeks post-subcutaneous inoculation, but bacterial burdens were significantly reduced in some tissues. Following intravenous inoculation, the Del202–208 bacteria were below the limit of detection in all tissues assessed at 2 weeks post-inoculation, but bacterial burdens recovered to wild-type levels at 4 weeks post-inoculation. The delay in tissue colonization correlated with reduced migration of the Del202–208 strains across microvascular endothelial cells, similar to Δp66 bacteria. These results indicate that integrin binding by P66 is important to efficient dissemination of B. burgdorferi, which is critical to its ability to cause disease manifestations in incidental hosts and to its maintenance in the enzootic cycle.
The differential diagnosis of mucin-producing adenocarcinoma of the prostate includes conventional prostatic adenocarcinoma with mucin production, secondary adenocarcinoma usually of colorectal origin and, very rarely, urothelial-type adenocarcinoma arising from either the prostatic urethra or proximal ducts. Conventional prostatic adenocarcinoma with mucin production is readily identified by routine microscopy and immunohistochemistry. The distinction between secondary adenocarcinoma and urothelial-type adenocarcinoma, however, can present a significant diagnostic challenge. In addition, documented examples of the latter in the prostate are exceptionally rare. A transurethral resection of prostate specimen and prostatic needle biopsies from two patients showing urothelial-type adenocarcinoma of the prostate were identified in our consultation files. One of the patients subsequently underwent a radical prostatectomy. Both patients had negative gastrointestinal endoscopic workups. Transurethral resection of prostate material from two patients with clinically confirmed secondary adenocarcinoma of colonic origin involving the prostate and a prostatectomy specimen with mucinous conventional prostatic adenocarcinoma were also identified for comparison purposes. Formalin-fixed, paraffin-embedded sections were stained for prostate-specific antigen (PSA), prostatic acid phosphatase, carcinoembryonic antigen, cytokeratin 7, cytokeratin 20 and high molecular weight cytokeratin 34bE12. The urothelial-type adenocarcinoma cases were diffusely positive for cytokeratin 7 and focally positive for 34bE12 and cytokeratin 20, consistent with an origin from the urothelium of the prostatic urethra or proximal prostatic ducts. In contrast, the secondary adenocarcinoma of colonic origin cases were diffusely cytokeratin 20 positive and either negative or focally positive for cytokeratin 7 and negative for 34bE12. The mucinous conventional prostatic adenocarcinoma was positive for PSA and prostatic acid phosphatase and negative for cytokeratin 7, cytokeratin 20 and 34bE12. All tumors were positive for carcinoembryonic antigen. Modern Pathology (2005) 18, 585-590. doi:10.1038/modpathol.3800317Keywords: urothelial carcinoma; mucinous adenocarcinoma; urethra; prostate; immunohistochemistry Carcinoma arising in the male urethra, with or without involvement of the prostate, is uncommon and usually occurs during the sixth and seventh decades, with 95% of cases occurring after the age of 45 years. 1 Obstructive symptoms due to a urethral mass or stricture are the usual presenting features. 2,3 Chronic irritation, infection, and trauma, including that from instrumentation used to relieve strictures, are the major predisposing factors. 1,2 In one series, 37% of patients had a history of venereal disease, 35% had stricture, and 7% had suffered trauma. 3 It has been reported that up to 88% of patients with urethral carcinoma have a history of urethral stricture. The most common site for stricture, the bulbomembranous urethra, is also the most comm...
is a causative agent of Lyme disease, the most common arthropod-borne disease in the United States. evades host immune defenses to establish a persistent, disseminated infection. Previous work showed that P66-deficient (Δ) is cleared quickly after inoculation in mice. We demonstrate that the Δ strain is rapidly cleared from the skin inoculation site prior to dissemination. The rapid clearance of Δ bacteria is not due to inherent defects in multiple properties that might affect infectivity: bacterial outer membrane integrity, motility, chemotactic response, or nutrient acquisition. This led us to the hypothesis that P66 has a role in mouse cathelicidin-related antimicrobial peptide (mCRAMP; a major skin antimicrobial peptide) and/or neutrophil evasion. Neither wild-type (WT) nor Δ was susceptible to mCRAMP. To examine the role of neutrophil evasion, we administered neutrophil-depleting antibody anti-Ly6G (1A8) to C3H/HeN mice and subsequently monitored the course of infection. Δ mutants were unable to establish infection in neutrophil-depleted mice, suggesting that the important role of P66 during early infection is through another mechanism. Neutrophil depletion did not affect WT bacterial burdens in the skin (inoculation site), ear, heart, or tibiotarsal joint at early time points postinoculation. This was unexpected given that prior studies demonstrated neutrophils phagocytose and kill These data, together with our previous work, suggest that despite the ability of host innate defenses to kill , individual innate immune mechanisms have limited contributions to controlling early infection in the laboratory model used.
Borrelia species transmitted by soft or hard ticks cause tick-borne relapsing fever (TBRF). This is a debilitating disease distributed worldwide but is likely underdiagnosed or misdiagnosed as Lyme disease due to poorly developed diagnostic tests. Borrelia turicatae , Borrelia parkeri , and Borrelia hermsii are three TBRF species previously implicated in human disease in North America.
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