79. Systems Analysis of Inactivated Influenza Vaccine Responses in Distinct Immune Cell Types
Session: Oral Abstract Session: Influenza Vaccine - Clinical Impact and Vaccine Response
Thursday, October 3, 2013: 8:30 AM
Room: The Moscone Center: 200-212

Background: Systems biology represents a new approach to studying human immune responses to vaccines.  We used this approach to determine if the biological pathways induced by trivalent influenza vaccination (TIV) in individual immune cell subsets are distinct from those in the pooled peripheral blood mononuclear cell (PBMC) population at early time points after vaccination. 

Methods:   Two healthy adult volunteers received a single dose of 2011-2012 seasonal trivalent IIV.  Blood was obtained prior to vaccination, and on Days 1, 3, and 7 after vaccination.  Using cell isolation techniques, including magnetic-activated and fluorescence-activated cell sorting, purified populations of T cells (CD3+), B cells (CD19+), neutrophils (CD15+), monocytes (CD14+), natural killer (NK) cells (CD56+), and myeloid dendritic cells (mDC's; CD56+) were obtained from fresh blood samples at >98% purity. A fraction of the cells were homogenized in RNA stabilization buffer and stored at -80 C.  Total RNA was extracted from the PBMC's and immune cell subsets using an automated procedure.  PolyA-enriched RNA-Seq libraries were prepared and 25 million, 50 BP, paired-end sequencing was performed.  These data were processed and analyzed using open-source and commercial software packages.  Hierarchical clustering analyses and Ingenuity Pathway Analysis (IPA) were performed. 

Results: Hierarchical clustering analysis of the transcriptomes revealed that purified individual immune cell subsets have distinct RNA expression profiles compared to the pooled PBMC population (Figure 1; yellow: up-regulation; blue: down-regulation).  Using shared transcripts that were up-regulated ³ two-fold from Day 0 to Day 1, IPA identified distinct gene networks induced by vaccination in each immune cell subset (Figure 2).

Conclusion:   Transcriptomic analysis reveals that each immune cell subset displays unique gene expression patterns after vaccination with 2011-2012 TIV, which cannot be fully appreciated when the PBMC population is analyzed as a whole. These methods are currently being applied to evaluation of an AS03-adjuvanted inactivated H5N1 vaccine.

Leigh Howard, MD1, Andrew Link, PhD2, Kristen Hoek, PhD2, Tara Allos2, Parimal Samir2, Kirsten Diggins3, Qi Liu, PhD3, Nripesh Prasad4, Megan Shuey3, Xinnan Niu5, C. Buddy Creech, MD, MPH6, Shawn Levy, PhD7, Sebastian Joyce, PhD8 and Kathryn Edwards, MD, FIDSA9, (1)Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, (2)Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, (3)Vanderbilt University, Nashville, TN, (4)HudsonAlpha, Huntsville, AL, (5)Vanderbilt University Medical Center, Nashville, TN, (6)Pediatric Infectious Diseases and Vanderbilt Vaccine Research Program, Vanderbilt University School of Medicine, Nashville, TN, (7)HudsonAlpha, huntsville, AL, (8)Vanderbilt University, nashville, TN, (9)Div of ID, Vanderbilt University Medical Center, Nashville, TN

Disclosures:

L. Howard, None

A. Link, None

K. Hoek, None

T. Allos, None

P. Samir, None

K. Diggins, None

Q. Liu, None

N. Prasad, None

M. Shuey, None

X. Niu, None

C. B. Creech, Novartis : Consultant, Consulting fee

S. Levy, None

S. Joyce, None

K. Edwards, None

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