In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

[Q]: Context: The blasticidin S resistance gene (bsr) is a selectable marker used for gene transfer experiments. The bsr gene encodes for blasticidin S (BS) deaminase, which has a specific activity upon BS. Therefore, its expression is supposed to be harmless in cells. The work reported on herein consisted of experiments to verify a possible toxicity of bsr on mammalian cells, which include several cell lines and primary cultures.', 'Murine keratinocyte BALB/MK and human primary keratinocyte cells transduced with the retroviral vector LBmSN, which has an improved expression system of bsr, namely bsrm, died in five days after the transduction. Meanwhile the control vector LBSN, which expresses bsr, did not provoke cell death. The lethal activity of bsrm was observed only in human keratinocytes and BALB/MK cells among the cell types tested here. Death appears to be mediated by a factor, which is secreted by the BALB/MK transduced cells.\Question: Is over expression of the selectable marker blasticidin S deaminase gene toxic to human keratinocytes and murine BALB/MK cells?
[A]: By our study we demonstrated that the expression of bsrm gene is toxic to human keratinocytes and BALB/MK cells. It is likely over expression of BS deaminase gene is responsible for the death.


[Q]: Context: Thus far, live attenuated SIV has been the most successful method for vaccinating macaques against pathogenic SIV challenge; however, it is not clear what mechanisms are responsible for this protection. Adoptive transfer studies in mice have been integral to understanding live attenuated vaccine protection in models like Friend virus. Previous adoptive transfers in primates have failed as transferred cells are typically cleared within hours after transfer.', 'Here we describe adoptive transfer studies in Mauritian origin cynomolgus macaques (MCM), a non-human primate model with limited MHC diversity. Cells transferred between unrelated MHC-matched macaques persist for at least fourteen days but are rejected within 36 hours in MHC-mismatched macaques. Cells trafficked from the blood to peripheral lymphoid tissues within 12 hours of transfer.\Question: Do allogeneic lymphocytes persist and traffic in feral MHC-matched mauritian cynomolgus macaques?
[A]: MHC-matched MCM provide the first viable primate model for adoptive transfer studies. Because macaques infected with SIV are the best model for HIV/AIDS pathogenesis, we can now directly study the correlates of protective immune responses to AIDS viruses. For example, plasma viral loads following pathogenic SIV challenge are reduced by several orders of magnitude in macaques previously immunized with attenuated SIV. Adoptive transfer of lymphocyte subpopulations from vaccinated donors into SIV-naïve animals may define the immune mechanisms responsible for protection and guide future vaccine development.


[Q]: Context: Helminth-derived molecules are being identified as a new therapeutic approach for immune-mediated diseases. We investigated the anti-inflammatory effect and the immunological mechanisms of Schistosoma mansoni soluble egg antigens (SmSEA) in a mouse model of chronic colitis.', 'Colitis was induced in immunocompromised severe combined immunodeficiency mice by the adoptive transfer of CD4CD25CD62L T cells. Two weeks post-transfer, SmSEA treatments were started (study 1: 1 × 20 μg SmSEA per week 5 times; study 2: 2 × 20 μg SmSEA per week 3 times). From the start of the treatment (week 2), the clinical outcome and colonic inflammation were assessed at different time points by a clinical disease score and colonoscopy, respectively. At the end of the studies, the colons were harvested for macroscopic examination, and colonic lamina propria mononuclear cells were isolated for flow cytometric T-cell characterization.', 'In both studies, administration of SmSEA in colitis mice improved all the inflammatory parameters studied. However in study 1, this beneficial effect on inflammation diminished with time, and the T-cell characterization of the lamina propria mononuclear cells, performed at week 6, revealed no immunological effects of the SmSEA treatment. In study 2, mice were killed earlier (week 4) and at that time point, we found a significant downregulation of the number of interleukin-17A-producing T cells and a significant upregulation of the number of interleukin-4-producing T cells in the colon of the SmSEA-treated colitis mice.\Question: Does treatment with egg antigens of Schistosoma mansoni ameliorate experimental colitis in mice through a colonic T-cell-dependent mechanism?
[A]:
Our results demonstrated that the administration of SmSEA reduces the severity of colitis in the adoptive transfer mouse model characterized by an increased Th2 response and a suppressed Th17 response in the colon.