B-ALL regress with DXM or IR treatments.
(A) B-ALL in rag2:hMYC fish treated with DXM for 9 days (n = 19). Post-treatment and relapsed images were obtained on days 9 and 28, respectively. Every (19/19) B-ALL regressed after DXM, but 11/19 (58%) B-ALL relapsed by day 28 (19 days after DXM withdrawal). (B) B-ALL in rag2:hMYC fish treated with IR (n = 13). Post-treatment and relapsed images were obtained on days 7 (i. e., 2 days after the 2nd IR dose) and 23, respectively. Every B-ALL (13/13) regressed after IR, but 100% recurred within 3 weeks of the 2nd IR dose. Upon relapse, flow cytometric testing (See Figure 1B) was used to verify that each relapse was GFPlo B-ALL. Images of rag2:hMYC, lck:GFP fish (top 5 animals) have had brightness enhanced to facilitate visualization of dim B-ALL. Images of the rag2:hMYC, cd79a:GFP fish (lowest animal) are unmodified.