Bacterial biofilms are responsible for the failure of many medical devices such as urinary catheters and are associated with many infectious and non-infectious complications. Preclinical and clinical evaluation of novel catheter coatings to prevent these infections needs to accurately quantify the bacterial load in the biofilm in vitro and ex vivo. There is currently no uniform gold standard for biofilm quantification for different surfaces and established biofilms. We have tried to establish a simple, accurate and reproducible method for extraction and measurement of biofilm bacteria on indwelling catheters, using a combination of vortexing and sonication. We demonstrate the usefulness of this method for catheters of different sizes – 3 Fr to 14 Fr – in vitro, in murine and porcine models, and indwelling in human clinical subjects. We also demonstrate consistent results with complex and polymicrobial biofilms. We believe that this standardized reproducible method will assist the assessment of biofilms in general and urological devices in particular in efforts to harness novel technologies to prevent healthcare associated infections.

The present gold standard for bladder cancer is Mycobacterium bovis, Bacillus Calmette Guerin (BCG) immunotherapy. But it has a non-responder rate of 30-50% and side effects are common. Lactobacillus casei strain Shirota has been reported to reduce the incidence of recurrence in bladder cancer patients and to cure tumor-bearing mice. Our aim was to determine if Lactobacillus rhamnosus GG (LGG) could be as efficacious as BCG in a murine model of bladder cancer. MB49 bladder cancer cells secreting human prostate-specific antigen were implanted orthotopically in female C57BL ⁄ 6 mice and urinary prostate-specific antigen levels were used as a marker of tumor growth. Mice were treated with either live or lyophilized LGG given via intravesical instillation, or both oral and intravesical LGG given once a week for a period of 6 weeks starting at day 4 after tumor implantation. A comparison of LGG and BCG immunotherapy was also carried out. LGG therapy (live or lyophilized) significantly (P = 0.006) increased the number of cured mice. Cytokine arrays and immune cell recruitment analysis revealed differences between untreated, treated, cured, and tumor-bearing mice.LGG therapy restored XCL1 levels to those in healthy bladders.LGG also recruited large numbers of neutrophils and macrophages to the tumor site. Intravesical LGG and BCG immunotherapy had cure rates of 89 and 77%, respectively, compared with 20% in untreated mice.LGG has the potential to replace BCG immunotherapy for the treatment of bladder cancer. (Cancer Sci 2010; 101: 751-758)

Lactobacillus species induced cytotoxic effects in bladder cancer cells. Unlike BCG, it requires bacterial protein synthesis. Like BCG, L. casei Shirota induces cell death primarily via necrosis. The cytoxicity of these lactobacilli in bladder cancer cells raises the possibility of using this species of bacteria as intravesical agents for treating bladder cancer.

This study evaluates the ability of Lactobacillus rhamnosus GG (LGG) to activate DC and neutrophils and modulate T cell activation and the impact of bacterial dose on these responses. Murine bone marrow derived DC or neutrophils were stimulated with LGG at ratios of 5 : 1, 10 : 1, and 100 : 1 (LGG : cells) and DC maturation (CD40, CD80, CD86, CD83, and MHC class II) and cytokine production (IL-10, TNF-α, and IL-12p70) were examined after 2 h and 18 h coculture and compared to the ability of BCG (the present immunotherapeutic agent for bladder cancer) to stimulate these cells. A 2 h exposure to 100 : 1 (high dose) or an 18 h exposure to 5 : 1 or 10 : 1 (low dose), LGG : cells, induced the highest production of IL-12 and upregulation of CD40, CD80, CD86, and MHC II on DC. In DCs stimulated with LGG activated neutrophils IL-12 production decreased with increasing dose. LGG induced 10-fold greater IL-12 production than BCG. T cell IFNγ and IL-2 production was significantly greater when stimulated with DC activated with low dose LGG. In conclusion, DC or DC activated with neutrophils exposed to low dose LGG induced greater Th1 polarization in T cells and this could potentially exert stronger antitumor effects. Thus the dose of LGG used for immunotherapy could determine treatment efficacy.

The use of upconversion nanoparticles (UCNPs) for treating deep‐seated cancers and large tumors has recently been gaining momentum. Conventional approaches for loading photosensitizers (PS) to UCNPs using noncovalent physical adsorption and covalent conjugation had been previously described. However, these methods are time‐consuming and require extra modification steps. Incorporating PS loading during the controlled UCNPs assembly process is seldom reported. In this study, an amphiphilic copolymer, poly(styrene‐co‐maleic anhydride), is used to instruct UCNPs assembly formations into well‐controlled UCNPs clusters of various sizes, and the gap zones formed between individual UCNPs can be used to encapsulate PS. This nanostructure production process results in a considerably simpler and reliable method to load PS and other compounds. Also, after considering factors such as PS loading quantity, penetration in 3D bladder tumor organoids, and singlet oxygen production, the small UCNPs clusters displayed superior cell killing efficacy compared to single and big sized clusters. Therefore, these UCNPs clusters with different sizes could facilitate a clear and deep understanding of nanoparticle‐based delivery platform systems for cell killing and may pave a new way for other fields of UCNPs based applications.