Autoimmune hemolytic anemia (AIHA) is characterized by the production of antibodies directed against self red blood cells. Given the frequent association between AIHA and other autoimmune disorders, generalized immune dysfunction likely plays a role in the disease process. Under normal conditions, self-reactive lymphocytes are killed, inactivated or suppressed by regulatory T cells, resulting in unresponsiveness to selfantigens. Disruption of these control mechanisms results in the survival and pathogenic activation of selfreactive lymphocytes. It is unclear how self-reactive lymphocytes are spontaneously activated in the absence of overt infection or other stimuli, leading to autoimmune disease. If the initiators of activation and subsequent disease can be delineated, and the antigen targets of pathogenic antibodies identified, means of controlling these autoimmune reactions may be uncovered. In this study, we use a mouse model of spontaneous, acute systemic autoimmunity that principally manifests as AIHA to define the stimuli that are required for the development of autoimmune disease. The overall objective of this proposal is to define the immunological abnormalities in a model of spontaneous autoimmunity and to identify the target antigens in this disease. The central hypothesis underlying this proposal is that abnormal cytokine production and uncontrolled activation of dendritic cells due to the absence of regulatory T cell suppression results in autoimmunity. The successful completion of this project will elucidate the immune abnormalities (including the role of dendritic cells, cytokines and antigen-specific lymphocytes) in AIHA development, and strengthen our understanding of what triggers and maintains autoimmunity. I will proceed with the mentored phase of this project under the guidance of Dr. Abul Abbas at the University of California San Francisco, and then look forward to completing these aims as an independent investigator.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Career Transition Award (K99)
Project #
1K99HL090706-01A1
Application #
7586913
Study Section
Special Emphasis Panel (ZHL1-CSR-Z (O1))
Program Officer
Werner, Ellen
Project Start
2009-07-01
Project End
2011-06-30
Budget Start
2009-07-01
Budget End
2010-06-30
Support Year
1
Fiscal Year
2009
Total Cost
$90,000
Indirect Cost
Name
University of California San Francisco
Department
Pathology
Type
Schools of Medicine
DUNS #
094878337
City
San Francisco
State
CA
Country
United States
Zip Code
94143
Isakson, Sara H; Katzman, Shoshana D; Hoyer, Katrina K (2012) Spontaneous autoimmunity in the absence of IL-2 is driven by uncontrolled dendritic cells. J Immunol 189:1585-93