TABLE 2.

Donor-specific antibody and crossmatch results of desensitized patients^a,b

Patient	VXM	T-cell FXM	B-cell FXM	DSA	Pretransplant MFI	Day 21 MFI	Month 12 MFI	Outcome
1	PositiveA3, B41, B45, C16, C17	Positive	Positive	B45, Bw6	8396	2784	486	No rejection to dateAlive 3 y and 6 mo
				B41, Bw6	7698	1052	288
				Cw16	1108	858	304
				Cw17	1134	884	532
2	Never assessed	Positive	Positive	B13, Bw4	1700	98	2	Grade 2R ACR at 83 dGrade 1R ACR at 323 dAlive 2 y and 4 mopost-HT
				B35, Bw6	9939	4829	14
				Cw4	1856	533	86
3	PositiveDR4, DRw51	Negative	Positive	DR4	2589	1310	338	No rejection to dateAlive 2 y and 6 mopost-HT
				DRw51	2816	1190	2723
				DQ6	1076	494	52
4	Never assessed	Positive	Equivocal	A1	2986	Not drawn	147	No rejection to dateAlive 2 y and 6 mopost-HT
				DR4	2512	Not drawn	0
5	PositiveB35, B72, DP1	Positive	Positive	B51, Bw4	1349	2218	274	Grade 1 pAMR at 10 dRequired VA-ECMO for PEA arrest and biventricular dysfunctionAlive 2 y and 5 mopost-HT
				B53, Bw4	2188	3451	0
				Cw4	1024	125	0
				Cw16	5802	596	0
				DP1	0	1541	43
6	PositiveB37, DQ5	Positive	Negative	B37, Bw4	5566	552	88	No rejection to dateAlive 1 y and 11 mopost-HT
				DQ5	1025	509	382
7	PositiveDR13, DQ6	Negative	Negative	DQ6	None	Not drawn	3273	No rejection to dateAlive at 1 y and 10 mo
8	PositiveA3, DR103, DR11, DQ5	Equivocal	Equivocal	A3	8354	454	Deceased	Withdrawal of care on POD 49 after complicated VA-ECMOcourse for PGDBiopsy with ischemic necrosis
				DR103	2780	245
				DQ5	11 377	2356
9	PositiveA1	Positive	Positive	A1	8185	8185	6898	No rejection to dateAlive at 1 y and 5 mo post-HT
10	PositiveDR4	Negative	Positive	DR4	1222	1139	1345	No rejection to dateAlive at 1 y and 5 mo post-HT

^aThe VXM was reported as positive when DSA to either HLA class I or II antigen was detected in the current or historic specimen with an MFI value ≥1000.

^bFor the FXM, the shift median channel cutoffs were determined through evaluation of donor cells with negative control serum. Shifts ≤2 standard deviations from the mean were considered negative, shifts ≥3 standard deviations were positive, and shifts between 2 and 3 standard deviations were considered equivocal. A 5% false positive and 5% false negative rate is expected with the FXM.

ACR, acute cellular rejection; DSA, donor-specific antibody; FXM, flow cytometry crossmatch; HT, heart transplant; MFI, mean fluorescence index; pAMR, pathologic antibody-mediated rejection; PEA, pulseless electrical activity; PGD, primary graft dysfunction; POD, postoperative d; VA-ECMO, veno-arterial extracorporeal membrane oxygenation; VXM, virtual crossmatch.