Anticipation of Relapse and Acute Graft-Versus-Host Disease after Allogeneic Peripheral Blood Stem Cell Transplantation: The Fundamental Role of Antigen-Presenting (Dendritic) Cells

Figures & data

Figure 1 Graft components and clinical features of the 29 recipients that underwent allogeneic PBSCT. Schematic box plots representing the correlations of CD34⁺ cell counts and different types of DC among 29 grafts. (A) Correlation between CD34⁺ and CMRF44⁺ DC counts; (B) correlation between CMRF44⁺ DC and DC1 counts; (C) correlation between CMRF44D⁺ and DC2 counts; (D) correlation between DC1 and DC2 counts. Underlying diseases (E), cytogenetic profiles (F), and conditioning regimens (G) following allogeneic PBSCT. (H) Flowchart of PBSC-recipient outcomes. (I) Kaplan–Meier graphs of cumulative survivors free of acute GVHD and relapse 100 days after allogeneic PBSCT among subcohorts with high and low DC counts. (J) Percentage of survivors among subcohorts with high and low DC counts.

Abbreviations: DC, dendritic cell; SAA, severe aplastic anemia; β-TM, β-thalassemia major; NHL, non-Hodgkin’s lymphoma; MDS, myelodysplastic syndrome; HDL, Hodgkin’s lymphoma; ALL, acute lymphoblastic leukemia; AML, acute myeloid leukemia; MM, multiple myeloma; CML, chronic myeloid leukemia; inv(16), chromosome 16 inversion–associated translocations; del, deletion; t, translocation; Ph, Philadelphia chromosome; aGVHD, acute graft-versus-host disease; PBSCT, peripheral blood stem–cell transplantation.

Table 1 Demographic characteristics, underlying hematologic disorders, treatment, response, cytogenetic profiles and HLA compatibility of the 29 recipients that underwent aPBSCT

Diagnosis	n	Cytogenetic	n	Pretransplant therapy	State of disease at transplantation	HLA compatibility
Acute myeloid leukemia (AML), n=8	8 (27.6%)	Normal	3 (37.5%)	Standard 3/7 induction	7 (87.5%) CR1 1 (12.5%) CR1	Identical (100%) ≥1 alleles/antigens (0)
*M1 AML	5 (17.2%)	t(8;21)(q22;q22)	3 (37.5%)
*M4 AML	1 (3.5%)	inv(16)(p13q22)	1 (12.5%)
*M5 AML	2 (6.9%)	t(9;11)(p21–22;q23)	1 (12.5%)
Acute lymphoblastic leukemia (ALL), n=5	5 (17.4%)	Ph^–	5 (100%)	Multiagent chemotherapy	4 (80.0%) CR1 1 (20.0%) CR1	Identical (100%) ≥1 alleles/antigens (0)
*Pro-B ALL	2 (6.9%)	Trisomy 8	1 (20%)
*Common-B ALL	1 (3.5%)	Normal	1 (20%)
*T-cell ALL	2 (6.9%)	Normal	2 (40%)
Chronic myeloid leukemia, n=2	2 (6.9%)	Ph^+(9;22)(q34;q11)	2 (100%)	Second-line TKIs	Chronic phase	Identical (100%) ≥1 alleles/antigens (0)
Multiple myeloma, n=1	1 (3.5%)	t(4;14)(p16;q32)	1 (100%)	VRD then HDT	Remission	Identical
Non-Hodgkin’s lymphoma, n=1	1 (3.5%)	Unknown	1 (100%)	R-CHOP then high-dose chemotherapy	Remission	Identical
Hodgkin’s lymphoma, n=1	1 (3.5%)	Unknown	1 (100%)	ICE then high-dose chemotherapy	Remission	Identical
Myelodysplastic syndrome	3 (10.3%)	Normal	3 (100%)	Induction chemotherapy	Remission	Identical (100%) ≥1 alleles/antigens (0)
Severe aplastic anemia, n=6*	6 (20.7%)	Trisomy 8	4 (66.6%)	CyA+ATG ± Tpo-RA	NR	Identical (100%) ≥1 alleles/antigens (0)
		7q del	1 (16.7%)
		Normal	1 (16.7%)
β-thalassemia major, n=2	2 (6.9%)	1B-36 del	1 (50.0%)	Genotyped RBCS transfusions	Transfusion-dependent	Identical (100%) ≥1 alleles/antigens (0)
		Unknown	1 (50.0%)
Mean age (years)	19.7+1.9
Sex (M/F)	20/9 (2.2/1)

Notes: *Morphological diagnosis was aplastic anemia in all aplastic anemia patients without cytogenetic abnormalities where cytogenetic studies were carried out at diagnosis. One patient received pediatric-style multiagent chemotherapy.

Abbreviations: inv(16), chromosome 16 inversion–associated translocation; del, deletion; t, translocation; Ph, Philadelphia chromosome; VRD, bortezomib, lenalidomide, and dexamethasone; HDT, high-dose therapy; TKIs, tyrosine-kinase inhibitors; R-CHOP, rituximab, cyclophosphamide, hydroxydaunorubicin hydrochloride (doxorubicin hydrochloride), oncovin, and prednisone; ICE, ifosfamide carboplatin etoposide; CyA, cyclosporin A; ATG, antithymocyte globulin; Tpo-RA, thrombopoietin receptor agonist; CR, complete remission; NR, no response.

Table 2 GVHD stage and grade, graft-DC components, medications, and outcomes of those who developed aGVHD

	Sex	Underlying Diagnosis	Graft-DC components (X10^6 DC/L blood)			Day of engraftment		aGVHD stage			aGVHD grade	aGVHD medication	Response	Outcomes
			CMR44^+ DCs	DC1	DC2	Neut	Plt	Skin	Liver	Gut
Case 19	M	SAA	11.7	5.6	6.0	17	18	+	–	+	I	Topical	CR	Recovery
Case 20	M	SAA	*24.5	*19.6	5.3	27	27	++	+	++	II	S-steroids	CR	Recovery
Case 21	F	HDL	13.1	6.0	7.7	12	12	+	–	–	I	Observation	CR	Recovery
Case 22	F	SAA	*28.0	*17.8	8.8	37	47	+++	++	+++	III	S-steroid+	CR	Recovery
Case 23	F	AML (M4)	*31.9	*21.2	10.3	43	0	+++	++++	++++	IV	S-steroid+	Progression	Died
Case 24	M	ALL (c-ALL)	*28.0	*23.6	3.9	22	25	++	++	+	II	S-steroid+	PR	Died
Case 25	M	ALL (PRO-B)	*18.3	11.2	6.3	13	20	++	+	++	II	S-steroids	CR	Recovery
Case 26	M	ALL (T-cell)	15.8	7.6	9.5	16	13	+	–	+	I	Topical	CR	Recovery
Case 27	F	AML (M1)	14.0	8.7	4.7	14	16	+	+	–	I	Topical	CR	Recovery

Notes: *P<0.05. S-steroids: systemic steroids (methylprednisolone) + original immunosuppressive prophylaxis (cyclosporine or tacrolimus). S-steroid+: systemic steroids with additional agent (such as MMF/etanercept/other).

Abbreviations: SAA, severe aplastic anaemia; HDL, Hodgkin’s lymphoma; AML, acute myeloid leukemia; ALL, acute lymphoblastic leukemia; ALL (c-ALL), common-B ALL; DC, dendritic cell; Plt, platelet count >20×10⁹/L; Neut, neutrophil count >0.5×10⁹/L; aGVHD, acute graft-versus-host disease; PR, partial response; CR, complete response.

Figure 2 Comparisons between variables of graft components in group II (cases with acute GVHD) versus group I (event-free group). Total leukocyte count (A), volume of PBSC (B), total nucleated cells (C), percentage of gated cells (D), percentage (E) and count (F) of CD34⁺ cells, CMRF44⁺ DC count (G), DC1 count (H), DC2 count (I), and recipient weight (J) between group I and group II. (K) Comparison of CMRF44D⁺ DC and DC1 counts among patients with different grades of aGVHD. (L) Flow-cytometry analysis of DC counts in PBSC harvests for recipients (n=23) who suffered grade IV aGVHD after allogeneic PBSCT: right, increased DC counts represented by CMRF44⁺ DC FITC; left, increased DC1 counts represented by CD11c⁺ DC PE.

Notes: ***P<0.001; **P<0.01.

Abbreviations: TLC, total leukocyte count; TNC, total nucleated cells; DC, dendritic cell; aGVHD, acute graft-versus-host disease; PBSC, peripheral blood stem cell; NS, not significant; FITC, fluorescein isothiocyanate; PE, phycoerythrin.

Figure 3 (A–C) Comparisons between variables of graft components in group III (cases with relapse) versus group I (event-free group). CMRF44⁺ DC (A), DC1 (B), and DC2 counts (C) in group I and group III. (D and E) Flow-cytometry analysis of DC counts in PBSC harvests for recipients (n=28) who suffered relapse after allogeneic PBSCT: (D) increased DCs represented by CMRF44⁺ DC FITC; (E) increased DC2 counts represented by CD4^bright DC FITC. (F–I) Correlations of CD34⁺-cell and DC counts and days of hospitalization after PBSCT: CD34⁺ cell count (F), CMRF44⁺ DC count (G), DC1 count (H), DC2 count (I), and days of hospitalization after PBSCT. CD34⁺ cell (J) and CMRF44⁺ DC counts (K) in group of patients without events and complications group. (L) Percentage of survivors among group I, II, and III subcohorts.

Notes: ***P<0.001; **P<0.01; *P<0.05.

Abbreviations: DC, dendritic cell; PBSCT, peripheral blood stem–cell transplantation; NS, not significant; FITC, fluorescein isothiocyanate; PE, phycoerythrin.

Table 3 Comparison between different variables of graft components in group II (cases with acute GVHD) versus group I (event-free group)

	Group I (n=18)	Group II (n=9)	P
Prepharesis TLC (×10^9/L)
●Mean + SD	48.9±15.2	51.9±18.1	0.681
●95% CI	41.3–56.5	37.9–65.8
●Median	47.6	50.4
Volume (mL^3)
●Mean + SD	192.9±36.7	207±29.8	0.280
●95% CI	174.7–211.2	184.3–230.1
●Median	195	200
Total nucleated cells (×10^6/L)
●Mean + SD	411.5±206.8	459.3±233.9	0.777
●95% CI	308.7–514.4	279.5–6.39.7
●Median	385	400
Weight (kg)
●Mean + SD	55.9±22.4	53.4±20.4	0.662
●95% CI	44.9–67.0	37.8–69.1
●Median	61.5	56
Gated cells (%)
●Mean + SD	30.3±10.8	24.6±11.8	0.111
●95% CI	24.9–35.6	24.6–33.7
●Median	34.1	28
CD34 cells (%)
●Mean + SD	2.5±1.3	2.5±1.6	0.837
●95% CI	1.8–3.2	1.3–3.8
●Median	2.2	2.2
CD34^+ cells (×10^6/kg)
●Mean + SD	14.5±11.5	9.2±7.3	0.117
●95% CI	8.8–20.2	3.6–14.8
●Median	9.6	4.6
DC count (absolute)
●Mean + SD (×10^6/L)	8.6±3.7	20.6±7.6	<0.001***
●95% CI	6.8–10.5	14.6–26.4
●Median	9.9	18.3
DC1 count (absolute)
●Mean + SD (×10^6/L)	4.6±2.4	13.5±7.1	<0.001***
●95% CI	3.4–5.8	8.1–18.9
●Median	4.1	11.2
DC2 count (absolute)
●Mean + SD (×10^6/L)	3.5±3.3	6.9±2.2	0.009**
●95% CI	1.9–5.2	5.2–8.7
●Median	3.2	6.3

Notes: ***P<0.001; **P<0.01.

Abbreviations: TLC, total leukocyte count; DC, dendritic cell.

Table 4 Associations between DC numbers and day of myeloid and platelet engraftments in allogeneic PBSCT recipients

	Time to engraftment (days)		P
	Group I	Group II	aGVHD	DCs	DC1
	Mean ± SD	Mean ± SD
Myeloid (≥0.5×10^9/L)	13.94±1.12	21.88±3.7	0.014*	0.02*	0.04*
Platelets (≥ 20×10^9/L)	14.38±1.13	17.55±4.8	0.4	0.88	0.66

Note: *P<0.05.

Abbreviations: DCs, dendritic cells; aGVHD, acute graft-versus-host disease.

Figure 4 (A) Estimated marginal means of DCs, DC1, and DC2. (B) Matrix of correlations showing associations between variables of graft components and patient weight. Values in cells are Spearman correlation coefficients.

Notes: ***P<0.001; **P<0.01; *P<0.05.

Abbreviations: Preph. TLC, peripheral total leukocyte count; Vol, volume of the graft; TNC, total nucleated cells; GC, gated cells; DC, dendritic cell; NS, not significant.