Sarah
Sarah
Algonquin Regional High School
Mentors:
Sachin V. Kammula & Athaliah Fubara
Cancer Program
Sarah's BSSP project explored a question at the intersection of leukemia biology and immunotherapy: how do cancer cells prevent immune cells from attacking them effectively? Working in the TIDE/Cancer Program with her partner Victor Ly, she focused on CD43, a heavily glycosylated surface protein found on acute myeloid leukemia (AML) cells.
Previous work showed that sialylated CD43 can help leukemia evade both macrophages and T cells, but the details of the cell-to-cell interaction remain incompletely understood. Sarah and Victor worked to develop and optimize assays that would allow researchers to directly observe contacts between T cells and AML cells with normal CD43 or CRISPR-engineered CD43 knockout cells.
Sarah helped test different T cell-to-leukemia ratios and incubation times, stain cells with fluorescent markers, analyze doublet formation by flow cytometry, and examine interactions using imaging flow cytometry and live-cell imaging. She learned that building a useful biological assay often requires substantial optimization: cell ratio, timing, fluorescent signal, controls, and imaging conditions all determine whether a true interaction can be distinguished from noise.
The experiments indicated that 1:1 and 1:2 T cell-to-AML ratios and a 30-minute incubation produced useful interaction conditions. CD43-knockout samples showed more doublets on average than controls, and imaging revealed examples of multiple T cells contacting a single CD43-knockout leukemia cell. Although the imaging methods still require refinement, Sarah's contribution establishes conditions for future studies of how CD43 may interfere with immune synapse formation and how that barrier might be therapeutically targeted.
Sarah described BSSP ’26 as a “unique and unforgettable experience,” and her project helped make the Broad feel like a scientific environment she could imagine joining in the future. She especially valued the welcoming, interactive community around her and the opportunity to study cell-surface proteins in leukemia while having fun with the people doing the science alongside her.
