The normal cellular counterpart and etiology of B cell chronic lymphocytic leukemia (CLL), the most common leukemia in Western counties, still remains unknown. Fundamental to this knowledge gap is a limited awareness of the biological heterogeneity of human memory B cells. These issues are important challenges for determining CLL pathogenesis because without a more thorough understanding of this relationship, improving prevention, diagnostic, treatment, and vaccination strategies will continue to be difficult. The long-term goal is to understand the link between normal B cell development and the pathogenesis of CLL. The objective of this proposal is to analyze the molecular and functional features of newfound subpopulations in the human memory B cell repertoire to define the normal CLL-counterpart. The central hypothesis is that members of an extended family of Fc receptor-like (FCRL) molecules with immunoregulatory function mark subsets of memory B cells from which CLL derives. The rationale for the proposed research is that the discovery of the B cell subpopulation from which CLL arises will provide new appreciation of its pathogenesis and enable more informed approaches for treating this incurable lymphoproliferative disorder. Based on our preliminary data, this hypothesis will be tested in two specific aims:
Aim 1 proposes to determine whether a memory B cell subset defined by FCRL expression molecularly resembles the pre-transformed CLL counterpart and Aim 2 will investigate the functional characteristics of FCRL expressing memory B cells. The contribution of this research will be significant because it will provide a comprehensive analysis of newfound memory B cell subpopulations to reveal for the first time the cellular origin(s) of CLL, help elucidate unexplored mechanisms involved in humoral immunity, and generate new knowledge for developing preventive and interventional strategies that link immune dysregulation and cancer. The proposed research is innovative because it overcomes previous less selective approaches by employing unique biomarkers of CLL possessing modulatory function that define previously unappreciated subsets in the human memory B cell repertoire resembling CLL cells. This novel strategy, will disclose molecular and functional features of these cells, shift our recognition of memory B cell diversity, assist in unearthing the CLL counterpart, and advance understanding of its pathogenesis. These outcomes are expected to have a positive impact because they will provide new avenues for researchers to develop preventative and therapeutic strategies for the treatment of CLL and other B cell disorders. Importantly, these studies should advance fundamental understanding of the dynamic interface between humoral immunity and the malignant transformation of B cells.

Public Health Relevance

The proposed research is significant to public health because it will investigate the normal cellular origin of B cell chronic lymphocytic leukemia (CLL) the mos common leukemia in Western countries. This work will be relevant to NIH's mission by providing fundamental knowledge to improve diagnostic, preventative, and therapeutic strategies for the treatment of CLL and other related disorders of B lymphocytes.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21CA175912-01A1
Application #
8637334
Study Section
Special Emphasis Panel (ZCA1-RTRB-Z (O1))
Program Officer
Howcroft, Thomas K
Project Start
2014-01-01
Project End
2015-12-31
Budget Start
2014-01-01
Budget End
2014-12-31
Support Year
1
Fiscal Year
2014
Total Cost
$191,835
Indirect Cost
$61,335
Name
University of Alabama Birmingham
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
063690705
City
Birmingham
State
AL
Country
United States
Zip Code
35294
Li, F J; Won, W J; Becker Jr, E J et al. (2014) Emerging roles for the FCRL family members in lymphocyte biology and disease. Curr Top Microbiol Immunol 382:29-50