The candidate's long term goals are to be an independent translational investigator and to improve the safety of blood transfusion by understanding mechanisms of immunosuppressive effects of stored red blood cells (RBCs). The objectives of this proposal are to provide the candidate with early translational research training and to determine the role of microRNA as mediators of red blood cell storage-related innate immune suppression. Innate immune suppression is common in critically ill children and is associated with adverse outcomes. Up to 49% of children who are in the intensive care unit for greater than 48 hours will receive an RBC transfusion. RBC transfusion has been shown to be immunosuppressive through unknown mechanisms. Older stored RBCs suppress innate immune cell (monocyte) function in vitro via heat-stable, soluble mediators capable of interfering with pro-inflammatory cytokine production at the mRNA level. MicroRNA (miRNA) is small, heat- stable, non-coding RNA capable of regulating multiple genes. RBCs contain miRNA and the relative abundance of specific miRNA may change over time during RBC storage. The central hypothesis of this proposal is that stored RBCs suppress monocyte function via the action of specific miRNA.
Specific Aim one will comprehensively identify changes in RBC miRNA content over storage duration and determine changes in gene expression in monocytes after exposure to variably aged RBC products. A computational approach will be used to determine miRNA likely responsible for observed immunosuppressive effects of stored RBCs on monocytes.
Specific Aim 2 will provide experimental evidence for immunosuppressive effects of specific miRNA.
Specific Aim 3 will demonstrate the feasibility of a miRNA- targeted strategy to prevent RBC-induced monocyte suppression. The work described in this submission will lend novel mechanistic insights into RBC transfusion-related innate immune suppression. The conduct of these studies and specific instruction in basic science techniques, molecular immunology, microRNA biology, biostatistics, bioinformatics, and transfusion medicine will support the candidate's transition to independence.

Public Health Relevance

The public health knowledge gained by the proposed research will be to understand key mechanisms of immunologic effects of red blood cell transfusion. This knowledge has the potential to improve outcomes for the large number of critically ill children and adults transfused in the US each year.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Clinical Investigator Award (CIA) (K08)
Project #
5K08HL123925-04
Application #
9462206
Study Section
NHLBI Mentored Clinical and Basic Science Review Committee (MCBS)
Program Officer
Sarkar, Rita
Project Start
2015-07-01
Project End
2020-03-31
Budget Start
2018-04-01
Budget End
2019-03-31
Support Year
4
Fiscal Year
2018
Total Cost
Indirect Cost
Name
Nationwide Children's Hospital
Department
Type
DUNS #
147212963
City
Columbus
State
OH
Country
United States
Zip Code
43205
Almizraq, Ruqayyah J; Norris, Philip J; Inglis, Heather et al. (2018) Blood manufacturing methods affect red blood cell product characteristics and immunomodulatory activity. Blood Adv 2:2296-2306
Muszynski, Jennifer A; Guzzetta, Nina A; Hall, Mark W et al. (2018) Recommendations on RBC Transfusions for Critically Ill Children With Nonhemorrhagic Shock From the Pediatric Critical Care Transfusion and Anemia Expertise Initiative. Pediatr Crit Care Med 19:S121-S126
Muszynski, Jennifer A; Reeder, Ron W; Hall, Mark W et al. (2018) RBC Transfusion Practice in Pediatric Extracorporeal Membrane Oxygenation Support. Crit Care Med 46:e552-e559
Weiss, Scott L; Balamuth, Fran; Hensley, Josey et al. (2017) The Epidemiology of Hospital Death Following Pediatric Severe Sepsis: When, Why, and How Children With Sepsis Die. Pediatr Crit Care Med 18:823-830
Frazier, W Joshua; Muszynski, Jennifer A (2015) Fluid Resuscitation in Pediatric Sepsis: Lack of Data Versus Lack of Equipoise. Pediatr Crit Care Med 16:789-90