Abstract
The immunogenicity and efficacy of influenza vaccination are markedly lower in the elderly. Granzyme B (GrzB), quantified in fresh cell lysates, has been suggested to be a marker of cytotoxic T lymphocyte (CTL) response and a predictor of influenza illness among vaccinated older individuals. We have developed an influenza-specific GrzB ELISPOT assay using cryopreserved PBMCs. This method was tested on 106 healthy older subjects (ages 50-74) at baseline (Day 0) and three additional time points post-vaccination (Day 3, Day 28, Day 75) with influenza A/H1N1-containing vaccine. No significant difference was seen in GrzB response between any of the time points, although influenza-specific GrzB response appears to be elevated at all post-vaccination time points. There was no correlation between GrzB response and hemagglutination inhibition (HAI) titers, indicating no relationship between the cytolytic activity and humoral antibody levels in this cohort. Additionally, a significant negative correlation between GrzB response and age was observed. These results reveal a reduction in influenza-specific GrzB response as one ages. In conclusion, we have developed and optimized an influenza-specific ELISPOT assay for use with frozen cells to quantify the CTL-specific serine protease GrzB, as a measure of cellular immunity after influenza vaccination.
Original language | English (US) |
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Pages (from-to) | 44-50 |
Number of pages | 7 |
Journal | Journal of Immunological Methods |
Volume | 398-399 |
Issue number | 1 |
DOIs | |
State | Published - 2013 |
Keywords
- Cellular
- Cellular immunity
- Cytotoxic
- Cytotoxic T lymphocytes (CTL)
- ELISPOT
- Enzyme-linked immunospot assay
- Granzyme B
- Granzymes
- Human
- Immunity
- Influenza
- Influenza virus
- Killer cells
- Natural
- Perforin
- T-lymphocytes
- Viruses
ASJC Scopus subject areas
- Immunology and Allergy
- Immunology