UVM Theses and Dissertations
Format:
Print
Author:
Novinger, Leah J.
Dept./Program:
Cell and Molecular Biology Program
Year:
2013
Degree:
Ph. D.
Abstract:
An important relationship exists between the humoral immune response and breast cancer cells. Tumor-infiltrating B cells are commonly present in breast cancers and have also been identified in tumor-draining lymph nodes and in blood. The distribution of B cells that are mature, clonal, and tumor reactive in different locations of the body is unclear.
The first goal of this project was to determine if a genetic relationship was shared between B cells present in a breast cancer, the tumor-draining lymph node, or peripheral blood. We compared heavy and light chain immunoglobulin sequences derived from B cells present in the primary tumor, tumor-draining axillary lymph node, and blood of a patient with breast cancer.
The B cell populations in the lymph node were different in heavy chain gene distribution when compared to blood. Light chains within the tumor and tumor-draining lymph node had enrichment of replacement mutations over silent mutations in the complementarity determining regions suggesting antigen-mediated selection. The same junctional regions of multiple clonal heavy and light chain sequences in the tumor were also found in the axillary lymph node and not in blood. The clonal overlap observed between tumor and lymph node sequences was significant in both heavy and light chain populations.
The second goal of this project was to determine if B cells from tumor, tumor-draining lymph node, or peripheral blood of a patient with breast cancer could be used to create tumor-binding antibodies. Phage displayed scFv libraries created from these sources were enriched for binding to autologous tumor lysates. Sequence analysis of enriched populations demonstrated that the shared genetic relationship between tumor and lymph node existed with enrichment for binding to autologous tumor lysates. In addition, following enrichment individual scFvs derived from the tumor and lymph node libraries bound selectively to the subject's breast cancer cells and not to the same subject's corresponding non-cancer breast tissue.
These results indicate that the B-cells in the study subject's breast cancer were clonally related to B-cells in the axillary lymph node. B-cells present in tumor and lymph nodes were a rich source of tumor binding antibodies in this patient that also demonstrated important tumor binding selectivity. The localization of tumor reactive B cells facilitates their investigation in the context of the entire immune response to breast cancer. This information provides better understanding of the dynamic relationship of the hwnoral immune response to breast cancer. The results of this project will likely impact the choice of tissue sources used to generate phage displayed scFv libraries for panning on twnor-derived targets. The tumor specific antibodies identified in this study have potential for therapeutic development.
The first goal of this project was to determine if a genetic relationship was shared between B cells present in a breast cancer, the tumor-draining lymph node, or peripheral blood. We compared heavy and light chain immunoglobulin sequences derived from B cells present in the primary tumor, tumor-draining axillary lymph node, and blood of a patient with breast cancer.
The B cell populations in the lymph node were different in heavy chain gene distribution when compared to blood. Light chains within the tumor and tumor-draining lymph node had enrichment of replacement mutations over silent mutations in the complementarity determining regions suggesting antigen-mediated selection. The same junctional regions of multiple clonal heavy and light chain sequences in the tumor were also found in the axillary lymph node and not in blood. The clonal overlap observed between tumor and lymph node sequences was significant in both heavy and light chain populations.
The second goal of this project was to determine if B cells from tumor, tumor-draining lymph node, or peripheral blood of a patient with breast cancer could be used to create tumor-binding antibodies. Phage displayed scFv libraries created from these sources were enriched for binding to autologous tumor lysates. Sequence analysis of enriched populations demonstrated that the shared genetic relationship between tumor and lymph node existed with enrichment for binding to autologous tumor lysates. In addition, following enrichment individual scFvs derived from the tumor and lymph node libraries bound selectively to the subject's breast cancer cells and not to the same subject's corresponding non-cancer breast tissue.
These results indicate that the B-cells in the study subject's breast cancer were clonally related to B-cells in the axillary lymph node. B-cells present in tumor and lymph nodes were a rich source of tumor binding antibodies in this patient that also demonstrated important tumor binding selectivity. The localization of tumor reactive B cells facilitates their investigation in the context of the entire immune response to breast cancer. This information provides better understanding of the dynamic relationship of the hwnoral immune response to breast cancer. The results of this project will likely impact the choice of tissue sources used to generate phage displayed scFv libraries for panning on twnor-derived targets. The tumor specific antibodies identified in this study have potential for therapeutic development.