Mechanisms of Activation-Induced Chromatin Decondensation in the Lymphoid Lineage
Department, Center, or Institute
Biology
Presentation Format
Poster
Presentation Type
On-campus research
Description
During an immune response, ?? T cells undergo a dramatic change in chromatin configuration, from a very condensed organization seen in naïve cells to a decondensed state in activated cells. It has previously been demonstrated that this change in chromatin architecture is required for ab T cell proliferation. Since B cells, ?? T cells, and NK cells share the same lineage as ?? T cells, originating from a common lymphoid progenitor, we hypothesized that chromatin status could regulate their proliferation as well. Using flow cytometry, we analyzed chromatin status as a function of activation and found that in their basal (naïve) state, each cell type of the lymphoid lineage experiences a different state of chromatin condensation, which correlates with their known ability to proliferate in response to activation stimuli: the chromatin in both NK cells and ?? T cells is more decondensed than ?? T cells while B cells have similarly condensed chromatin. We then tracked chromatin decondensation during activation. Previous work in the lab showed that B cells and ?? T cells decondense chromatin in a similar manner, although there appears to be differences in kinetics between the two. Here, we show that NK cells, however, experience a lesser rate of decondensation compared to ?? T cells. Finally, we identified two distinct populations of ??T cells based on Thy1.2 staining. Thy1.2hi (naïve) decondensed chromatin similarly to ab T cells, whereas Thy1.2lo (memory) ?? T cells decondensed chromatin to a greater extent than ?? T cells. Previous work in the lab demonstrated that calcium regulates chromatin decondensation in ?? T cells, suggesting that other lymphocytes could utilize a similar mechanism for decondensation. Using BAPTA, a known calcium chelator, we show that calcium is required for proper chromatin decondensation in B cells. Future studies will investigate if calcium can also regulate the decondensation of ?? T cells and NK cells, establishing a conserved mechanism to control proliferation of the lymphoid lineage.
Session Number
5
Start Date and Time
4-9-2019 4:00 PM
Location
PAC Gym
Recommended Citation
Stuart, Sara; Johnson, Jamila; Irsik, Jeremy; and Scruggs, Ryan, "Mechanisms of Activation-Induced Chromatin Decondensation in the Lymphoid Lineage" (2019). Furman Engaged!. 490.
https://scholarexchange.furman.edu/furmanengaged/2019/all/490
Mechanisms of Activation-Induced Chromatin Decondensation in the Lymphoid Lineage
PAC Gym
During an immune response, ?? T cells undergo a dramatic change in chromatin configuration, from a very condensed organization seen in naïve cells to a decondensed state in activated cells. It has previously been demonstrated that this change in chromatin architecture is required for ab T cell proliferation. Since B cells, ?? T cells, and NK cells share the same lineage as ?? T cells, originating from a common lymphoid progenitor, we hypothesized that chromatin status could regulate their proliferation as well. Using flow cytometry, we analyzed chromatin status as a function of activation and found that in their basal (naïve) state, each cell type of the lymphoid lineage experiences a different state of chromatin condensation, which correlates with their known ability to proliferate in response to activation stimuli: the chromatin in both NK cells and ?? T cells is more decondensed than ?? T cells while B cells have similarly condensed chromatin. We then tracked chromatin decondensation during activation. Previous work in the lab showed that B cells and ?? T cells decondense chromatin in a similar manner, although there appears to be differences in kinetics between the two. Here, we show that NK cells, however, experience a lesser rate of decondensation compared to ?? T cells. Finally, we identified two distinct populations of ??T cells based on Thy1.2 staining. Thy1.2hi (naïve) decondensed chromatin similarly to ab T cells, whereas Thy1.2lo (memory) ?? T cells decondensed chromatin to a greater extent than ?? T cells. Previous work in the lab demonstrated that calcium regulates chromatin decondensation in ?? T cells, suggesting that other lymphocytes could utilize a similar mechanism for decondensation. Using BAPTA, a known calcium chelator, we show that calcium is required for proper chromatin decondensation in B cells. Future studies will investigate if calcium can also regulate the decondensation of ?? T cells and NK cells, establishing a conserved mechanism to control proliferation of the lymphoid lineage.