tetano
Editor, Senior Moderator
Clin Vaccine Immunol. 2015 Jun 17. pii: CVI.00101-15. [Epub ahead of print]
[h=1]Variations in disease severity outcomes for Influenza live viral challenges in man: Meta-analysis and potential role of pre-existing heterosubtypic cellular immunity.[/h] Pleguezuelos O[SUP]1[/SUP], Robinson S[SUP]1[/SUP], Fernandez A[SUP]1[/SUP], Stoloff GA[SUP]1[/SUP], Caparr?s-Wanderley W[SUP]2[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]OBJECTIVES:[/h] Live Influenza challenges in man are valuable models for testing the efficacy of vaccines and antiviral agents. Volunteers are treated with an investigational agent and their clinical outcomes post-challenge are compared to those of Placebo treated volunteers. Despite using a common protocol, recruitment criteria and a similar dose of the same challenge strain, we noticed differences in disease severity outcomes between Placebo groups from different studies. We investigated whether these differences were significant and, if so, whether any pattern was identifiable and its possible causes.
[h=4]METHODS:[/h] We compared the clinical outcomes post-challenge in Placebo groups from five clinical studies carried out between 2008 and 2013. Correlations between pre-challenge heterosubtypic cellular response (IFN-γ) and post-challenge clinical outcomes were also investigated in one study.
[h=4]RESULTS:[/h] Placebo groups from studies carried out between 2009 and 2010 attained significantly reduced (p<0.05) symptom scores post-challenge than Placebo groups from studies carried out in either 2008 or 2013. Also, in a 2010 study, the frequency of high influenza heterosubtypic cellular responders pre-vaccination was significantly lower in the test group (FLU-v) than in the Placebo group (p=0.04). Moreover, the Placebo group's increased pre-existing heterosubtypic cellular response correlated with reductions in symptom score and viral shedding post-challenge (p≤0.023). Only post-vaccination did the Test group display an equivalent correlation.
[h=4]CONCLUSIONS:[/h] The last influenza pandemic coincides with a significant reduction in disease severity outcomes. This reduction also appears to correlate with increased pre-existing influenza heterosubtypic cellular responses.
Copyright ? 2015, American Society for Microbiology. All Rights Reserved.
PMID: 26084515 [PubMed - as supplied by publisher]
[h=1]Variations in disease severity outcomes for Influenza live viral challenges in man: Meta-analysis and potential role of pre-existing heterosubtypic cellular immunity.[/h] Pleguezuelos O[SUP]1[/SUP], Robinson S[SUP]1[/SUP], Fernandez A[SUP]1[/SUP], Stoloff GA[SUP]1[/SUP], Caparr?s-Wanderley W[SUP]2[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]OBJECTIVES:[/h] Live Influenza challenges in man are valuable models for testing the efficacy of vaccines and antiviral agents. Volunteers are treated with an investigational agent and their clinical outcomes post-challenge are compared to those of Placebo treated volunteers. Despite using a common protocol, recruitment criteria and a similar dose of the same challenge strain, we noticed differences in disease severity outcomes between Placebo groups from different studies. We investigated whether these differences were significant and, if so, whether any pattern was identifiable and its possible causes.
[h=4]METHODS:[/h] We compared the clinical outcomes post-challenge in Placebo groups from five clinical studies carried out between 2008 and 2013. Correlations between pre-challenge heterosubtypic cellular response (IFN-γ) and post-challenge clinical outcomes were also investigated in one study.
[h=4]RESULTS:[/h] Placebo groups from studies carried out between 2009 and 2010 attained significantly reduced (p<0.05) symptom scores post-challenge than Placebo groups from studies carried out in either 2008 or 2013. Also, in a 2010 study, the frequency of high influenza heterosubtypic cellular responders pre-vaccination was significantly lower in the test group (FLU-v) than in the Placebo group (p=0.04). Moreover, the Placebo group's increased pre-existing heterosubtypic cellular response correlated with reductions in symptom score and viral shedding post-challenge (p≤0.023). Only post-vaccination did the Test group display an equivalent correlation.
[h=4]CONCLUSIONS:[/h] The last influenza pandemic coincides with a significant reduction in disease severity outcomes. This reduction also appears to correlate with increased pre-existing influenza heterosubtypic cellular responses.
Copyright ? 2015, American Society for Microbiology. All Rights Reserved.
PMID: 26084515 [PubMed - as supplied by publisher]