TCDIFLU · Impact of adjuvants on T cell differentiation after Influenza Vaccination analyzed at the Single Cell Level
FP7 — People (Marie Curie Actions)
- Duration
- 2011-03-01 → 2013-02-28
- EU contribution
- €180,084
- Participants
- 1
- Scheme
- MC-IEF
Lines connect the coordinator with its partners.
Results in brief
Impact of adjuvants on T cell differentiation after Influenza Vaccination analyzed at the Single Cell Level
TCDIFLU tried to reveal the presence of protective T cell subpopulations by detailed analysis of CD4+ and CD8+ T lymphocytes at the single cell level after influenza (flu) infection with mouse-adapted PR8 flu strain or immunisation with seasonal flu vaccine, with special consideration on the effect of adjuvants (MF59, alum) or other proprietary adjuvant candidates (host). In more detail the objectives were: - selection, design and validation of suitable primers for biomarker detection; - profiling of the differentiation state of single cell T lymphocytes in mice after flu vaccination: these studies determined the differentiation status of vaccine-specific CD4+ and CD8+ T lymphocytes in mice vaccinated with the seasonal flu vaccine; - profiling of the differentiation state of single cell T lymphocytes in mice after flu infection; - comparison of the T cell differentiation state in mice after vaccination with adjuvant; - assessment of functionality of induced memory T cell; - verification of gene expression data by assessing protein biomarker expression. Suitable primers for biomarker detection have been selected, designed and validated. The selection comprised literature search to choose appropriate biomarkers. Primers were designed using software and validated in the laboratory (specificity, efficiency, simplified limit of detection, competition). Flu specific CD8+ T cells were analysed for 18 different biomarkers at the single-cell level for different immunisation regimens. Mice were immunised with flu protein vaccine (H1N1 2009 California) or flu protein vaccine plus adjuvant (MF59 or AbISCO-100) or nucleic acid-based proprietary vaccine. The use of a nucleic acid-based proprietary vaccine shifted the main interest to CD8+ T cells. This is as well the reason for the change in adjuvant (alum to AbISCO). Single flu specific CD8+ T cells from the spleen or the draining lymph nodes were analysed at different time points post immunisation. Different frequency of flu specific CD8 T cells and different gene expression profiles were detected when immunising mice with protein vaccine, protein plus adjuvants or using nucleic acid-based vaccines. Especially, the activation status of cytolytic T lymphocytes and memory T cells has been assessed. This work can be used to clarify the mode of action of vaccines and assess their immunogenicity. The results might be used to decide about the future use of vaccine candidates or their modification in order to obtain a desired immune response. This pre-clinical work might be used for translation to human studies and clinical trials.
Data: CORDIS, © European Union
Project objective
Mutating viruses and resistance to drugs are the major challenges to overcome in influenza (flu) prevention and treatment. Virus-neutralizing antibodies are the key for protection against flu infection, but flu-specific CD4+ and CD8+ T cells play a significant role by providing help to B cells and in viral clearance, respectively.There are many vaccines against flu infection approved for human use. The generally effective seasonal vaccines, however, have a number of deficiencies, including the need to repeat the injections every year with a newly updated vaccine, which provides only antibody-dominated subtype-specific protection. Adjuvants are used to enhance the immune response to a vaccine. They lead to different types of cell-mediated immune responses. The T cell type (Th1, Th2, cytotoxic) and the magnitude of the immune response discriminate between viral clearance and immunopathology. Particular T cell subpopulations (like Th1 IFN-γ or CD8+ perforin or Fas expressing cells) may be responsible for protection after infection or vaccination and may give correlation to protective adjuvants.Studies of T cells using assays analyzing entire cell populations are not suitable to uncover these cell populations. We propose a detailed T cell differentiation profiling of CD4+ and CD8+ T lymphocytes at the single cell level after flu vaccination using the quantitative single cell multiplex RT-PCR method. Individual T lymphocytes purified from the vaccination site draining lymph nodes will be analyzed for the presence of up to twenty important differentiation markers. The results will be verified by additional methods, like flow cytometry or confocal microscopy.This project will reveal the presence of T cell subpopulations possibly correlated to protection after flu infection with mouse-adapted PR8 influenza strain or immunization with seasonal flu vaccine, with special consideration on the effect of adjuvants.""
Original text from CORDIS.
Participants
- GLAXOSMITHKLINE VACCINES SRL · SIENACoordinatorItaly
Links
Data: CORDIS, © European Union