P1613: SINGLE-CELL ANALYSIS FOLLOWING SARS-COV-2 MRNA VACCINE IN ALLOGENEIC HEMATOPOIETIC STEM CELL TRANSPLANTATION RECIPIENTS - E. Tranter; B. Obermayer-Wasserscheid; M.-L. Hütter-Krönke; C. Junkuhn; I.-W. Blau; G. L. Vuong; L. Bullinger; I.-K. Na (HemaSphere, 2022)