Erythropoietin (EPO) plays a central role in regulating erythroid development and recombinant EPO is widely used in patients to treat erythropoietic insufficiency. However, very little is known about the effect of EPO on non-erythroid cells. We recently found that Salmonella infection induces EPO production and erythroid expansion and that this has a beneficial effect on bacterial growth in vivo. Together, these data suggest a surprising level of crosstalk between the immune response to bacterial infection and the homeostatic regulation of erythroid development. Our goal in this exploratory application is to study this important new research area in more detail. Given the novelty and potential importance of erythroid-immune interactions, we believe greater understanding of this area could lead to the generation of new vaccines and therapeutics for bacterial infections. Our application specifically proposes to, (i) identify the cell population and bacterial products responsible for EPO production during infection, and (ii) examine whether EPO has direct and indirect effects on the immune response to infection. Overall, our proposal bridges two well-developed, but disconnected, research fields and is likely to have broader implications for understanding how erythroid development impacts immune responses to infectious disease.

Public Health Relevance

Typhoid fever is found in geographical areas that lack clean water or basic sanitation, and affects 27.1 million people and causes 217,000 deaths annually. Splenomegaly is a prominent feature of this infection and we recently found that this is caused by expansion of erythroid progenitor cells and is advantageous for bacterial growth. Our goal in this exploratory application is to define bacterial products and cell populations that give rise to elevated EPO production and examine the effect of EPO on the innate and adaptive immune response. Given the novelty of erythroid-immune interactions, we believe greater understanding of this area could lead to the generation of new vaccines and therapeutics for bacterial infections.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21HL112685-01A1
Application #
8400138
Study Section
Special Emphasis Panel (ZRG1-IDM-S (03))
Program Officer
Luksenburg, Harvey
Project Start
2012-07-01
Project End
2014-06-30
Budget Start
2012-07-01
Budget End
2013-06-30
Support Year
1
Fiscal Year
2012
Total Cost
$231,000
Indirect Cost
$81,000
Name
University of California Davis
Department
Veterinary Sciences
Type
Schools of Veterinary Medicine
DUNS #
047120084
City
Davis
State
CA
Country
United States
Zip Code
95618
Li, Lin-Xi; McSorley, Stephen J (2013) B cells enhance antigen-specific CD4 T cell priming and prevent bacteria dissemination following Chlamydia muridarum genital tract infection. PLoS Pathog 9:e1003707
Li, Lin-Xi; Atif, Shaikh M; Schmiel, Shirdi E et al. (2012) Increased susceptibility to Salmonella infection in signal regulatory protein ýý-deficient mice. J Immunol 189:2537-44
McGeachy, Mandy J; McSorley, Stephen J (2012) Microbial-induced Th17: superhero or supervillain? J Immunol 189:3285-91