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Biology subjects

Esteso, G.

Publications and source records attributed to Esteso, G..

2 recordsLinked to original sources

CyTOF analysis identifies unusual immune cells in urine of BCG-treated bladder cancer patients

High grade non-muscle-invasive bladder tumours are treated with transurethral resection followed by recurrent intravesical instillations of Bacillus Calmette Guerin (BCG). Although bladder cancer patients respond well to BCG, important questions remain unanswered, including how to identify at early stages non-responder patients and patients at risk to abandon the treatment. Here, we analysed the cells released into the urine of bladder cancer patients longitudinally 3-7 days after BCG instillations. Mass cytometry (CyTOF) analyses revealed that most cells were granulocytes and monocytes rather than effector lymphocytes, and most expressed activation markers. A novel population of CD15+CD66b+CD14+ CD16+ cells was very abundant in several samples and expression of these markers was confirmed using flow cytometry and qPCR. Samples of patients with a stronger inflammatory response contained more cells in urine; however, this was not due to haematuria, as the proportions of the cell populations observed were different from blood. We provide the proof-of-concept for a new approach to analyse samples that may help classify patients and identify those at risk of BCG infection and other unwanted BCG-related events.

immunology

Natural killer activation for bladder cancer elimination can be achieved in vitro by heat-killed BCG

Immunotherapy, via intravesical instillations of Bacillus Calmette-Guerin (BCG) is the therapy of choice for patients with high risk non-muscle invasive bladder cancer. The subsequent recruitment of lymphocytes and myeloid cells, as well as the release of cytokines and chemokines, induces a local immune response that contributes to eliminate these tumours. The history of BCG development resulted in a large number of genetically diverse BCG substrains which could stimulate the immune system in different ways. Here, while investigating the capacity of different BCG substrains to promote the activation of NK cells, we confirmed that all the evaluated substrains could activate a cytotoxic CD56bright NK cell population which efficiently degranulated against bladder cancer cells; Tice, Connaught and Moreau were the substrains having a stronger effect. Dead mycobacteria also stimulated PBMC cultures and we demonstrate that subcellular fractions of BCG-Tice could contribute to the induction of this NK cell response. Lipids from BCG-Tice, but not from Mycobacterium bovis, stimulated NK cell activation and degranulation, however the aqueous fraction of either bacteria did not activate lymphocytes. Delipidated BCG-Tice activated effector cells (CD3+CD56+ and NK). These data suggest that different immune subpopulations could be stimulated using different fractions of mycobacteria for cancer elimination.

immunology