Arpinati, M.

Baccarani, M.

Bandini, G.

Bonifazi, F.

Chirumbolo, G.

Giannoullia, P.

Rondelli, D.

Saunthararajah, Y.

Stanzani, M.

English

Elsevier - Publisher Connector 

Purpose: Thymoglobulin (ATG) given before allogeneic hema-
topoietic stem cell transplantation (HSCT) with unrelated donors
reduces acute graft-versus-host disease (GVHD). However, the
possible role of serum concentration of rabbit ATG for the sub-
sequent development of acute GVHD after HSCT is unknown.
Methods: The serum concentration of rabbit IgG was analyzed by
enzyme-linked immunosorbent assasy in 61 patients after unre-
lated donor HSCT. Doses of ATG as part of the conditioning
ranged between 4 and 10 mg/kg. Stem cell source was bone
marrow (BM) in 28 cases and peripheral blood (PBSC) in 33.
Conditioning was mainly cyclophosphamide combined with total
body irradiation (TBI) or busulfan. Most patients received GVHD
prophylaxis with cyclosporine and methotrexate. Results: Even
though we found a good correlation between given ATG dose and
serum concentration of rabbit IgG after transplant (r 0.67), there
was a wide variation of rabbit IgG levels within each dose group.
After administration, levels of rabbit IgG decreased slowly and
could still be detected up to 5 weeks after HSCT. We found a
correlation between grade of acute GVHD and concentration of
rabbit IgG in serum obtained before transplantation (P  .017).
Patients with serum levels of rabbit IgG 70 mg/ml before HSCT
had very low risk for developing acute GVHD grades II-IV com-
pared with those with  70 mg/ml (11% vs 53%; P  .001).
Conclusion: Measuring rabbit IgG levels in patients receiving
ATG as prophylaxis against GVHD after HSCT may be a helpful
tool in decreasing the risk of severe GVHD.
24
GENERATION OF TOLEROGENIC DENDRITIC CELLS AND REGULATORY
T CELLS THROUGH INTRAVENOUS DELIVERY OF AUTOLOGOUS PHO-
TOPHERESIS-INDUCED APOPTOTIC CELLS
Campbell, K.1; Huber, J.1; Rosenberg, A.1; Peters, C.1; Harriman, G.1;
Strobl, F.1; Peritt, D.1; Schwarz, A.2; Maeda, A.2; Schwarz, T.2 1.
Therakos, Inc., Exton, PA; 2. University Clinics Schleswig-Holstein,
Kiel, Germany.
Phagocytosis of apoptotic cells by macrophages or dendritic cells
has been shown to regulate immune responses both in vivo and in
vitro. Extracorporeal photopheresis (ECP) involves the clinical
reinfusion of peripheral blood leukocytes that are undergoing ap-
optosis following exposure ex vivo to 8-methoxypsoralen (8-MOP)
and UVA light. ECP is approved for the palliative treatment of
cutaneous T-cell lymphoma and has been reported to have utility
in immune-mediated inﬂammatory diseases, such as graft-versus-
host disease (GvHD) and solid-organ transplant rejection, and
autoimmune diseases, such as rheumatoid arthritis and Crohn’s
disease. We have evidence to suggest that ECP therapy may mod-
ulate host dendritic cell function and induce regulatory T-cell
generation. When coincubated with ECP-treated cells, activated
dendritic cells produce reduced levels of proinﬂammatory cyto-
kines, such as interleukin-12, whereas transforming growth fac-
tor- levels are modestly increased. Activation of CD4 T cells in
the presence of allogeneic dendritic cells and ECP-treated cells
promotes generation of a population of T cells that can suppress
proliferation of naive syngeneic T cells, as well as suppress inter-
feron- production. To conﬁrm these ﬁndings in vivo, we used a
murine contact hypersensitivity model. ECP-treated or control
leukocytes from mice sensitized with the hapten dinitroﬂuoroben-
zene (DNFB) were injected intravenously into naive recipients.
Compared with controls, mice that received ECP-treated cells
demonstrated signiﬁcantly less ear swelling after sensitization and
challenge with DNFB. Suppression of ear swelling was speciﬁc for
DNFB and was cell-mediated, as demonstrated by the ability to
transfer DNFB tolerance to naive mice, which could appropriately
respond to the unrelated hapten oxazalone. Transfer of this toler-
ance was abrogated by depletion of either CD4 or CD25T-cell
populations. Collectively, these results suggest that the delivery of
ECP-treated cells promotes generation of regulatory T cells that
are capable of modulating immune responses. Regulatory T cells
have been implicated in the control of GvHD, and as previously
reported, ECP has demonstrated beneﬁcial activity in GvHD. As a
result, international phase II clinical trials are currently underway
to assess the efﬁcacy of photopheresis in GvHD patients.
25
PRETRANSPLANT RECIPIENT BLOOD CD14 PREDC LEVELS CORRE-
LATE WITH INCREASED ACUTE GVHD AFTER ALLOGENEIC PBSC
TRANSPLANTATION
Arpinati, M.1; Giannoullia, P.1; Chirumbolo, G.1; Bonifazi, F.1; Saun-
thararajah, Y.2; Bandini, G.1; Stanzani, M.1; Baccarani, M.1; Rondelli,
D.2 1. Research Center for Transplant Immunology, Institute of Hema-
tology, University of Bologna, Bologna, Italy; 2. Section of Hematology/
Oncology, University of Illinois at Chicago, Chicago, IL.
Host dendritic cells (DCs) present host alloantigens to donor T
lymphocytes. Human peripheral blood contains various circulating
DC precursors including CD11c myeloid preDC (mDC),
CD14 monocytic DC precursors (CD14 preDC) and plasma-
cytoid preDC (pDC). We used ﬂow cytometry to enumerate both
mDC (lin-, HLA-DR, and CD11c), mono-DC (CD14), and
pDC (lin-, HLA-DR, and CD123) numbers in the blood of
patients receiving an allogeneic HSCT. Fifty consecutive patients
undergoing HSCT from HLA-matched related (n  28) or unre-
lated (n  22) donors were enrolled in the study. The stem cell
source was bone marrow in all unrelated donors, and branulocyte
colony-stimulating factor (G-CSF) mobilized PBSC in related do-
nors. All patients received CsA and MTX as GVHD prophylaxis.
Moreover, 26 patients (52%) received ATG before transplant.
mDC and pDC PB counts were signiﬁcantly lower in patients than
in 28 age-matched healthy controls (8.8 cells/l [25th-75th per-
centile, 3.5–14.5] mDC, and 2.8 [1.3–5.5] pDC, versus 15.5 [12.1–
25.1] and 8.6 [5.6–13.1], respectively; P  .001). However the
mDC/pDC ratio was signiﬁcantly higher in the patient group (3.5
[1.6–6.2] vs 1.7 [1.3–2.6]; P  .002). CD14 preDC counts were
not signiﬁcantly different. Among the 46 patients who were evalu-
able, 12 (26%) developed acute GVHD grade II-IV. Risk factors
signiﬁcantly associated with acute GVHD were older age (P 
.01), PBSC transplantation (P  .02), and the absence of ATG in
the conditioning regimen (P  .01). Patients with acute GVHD
had signiﬁcantly higher pretransplantation mDC:pDC ratio (5.7
[3.3–16.4] vs 3.1 [1.6–5.5]; P  .03) and CD14 preDC counts
(395 [326–625] vs 284 [187–395]; P  .02). A subset analysis was
performed in PBSC patients, only 3 of whom had received ATG
before transplant. Among 26 evaluable patients, 10 (38%) devel-
oped acute GVHD grade II-IV. Besides older age (P  .02), the
only risk factors signiﬁcantly associated with acute GVHD in
PBSC patients were the pretransplantation mDC:pDC ratio (5.7
[4.1–13.1] vs 1.7 [1.2–2.9]; P  .008) and CD14 preDC counts
(395 [352–710] vs 259 [199–314]; P  .004). In multivariate anal-
ysis, only older age (P  .04) and pretransplantation circulating
CD14 preDC numbers (P  0.04) were signiﬁcantly associated
with acute GVHD in PBSC transplants. These ﬁndings demon-
strate that blood levels of DC precursors may correlate with a
higher risk of developing aGVHD. Future studies will be aimed at
depleting host preDC before allotransplant as a means of GVHD
prophylaxis.
26
ACUTE AND CHRONIC GRAFT-VERSUS-HOST DISEASE (GVHD) IN PA-
TIENTS UNDERGOING ALLOGENEIC BMT FOR THALASSAEMIA MAJOR
George, B.; Mathews, V.; Viswabandhya, A.; Kavitha, N.; Srivastava,
A.; Chandy, M. Department of Haematology, Christian Medical College,
Vellore, Tamilnadu, India.
Methods: Between October 1991 and June 2004, 152 thalasse-
mic patients who underwent allogeneic BMT and survived more
than 2 weeks were evaluated for graft-versus-host disease
(GVHD). Conditioning regimens included cusulfan (Bu) 16 mg/
kg, cyclophosphamide (Cy) 200 mg/kg, and antilymphocyte glob-
ulin (ALG) 120 mg/kg (in 91 patients); Bu 600 mg/m2 and Cy 200
mg/kg (in 51 patients), Bu 14 mg/kg, Cy 10 mg/kg, and ALG 120
mg/kg (in 8 patients), and others (in 2 patients). GVHD prophy-
laxis consisted of cyclosporine (CSA) alone in 11 patients, CSA and
methotrexate (MTx) (15 mg/m2 on day 1, 10 mg/m2 on days 3, 6,
and 11) in 40 patients and CSA and MTx (10 mg/m2 on day 1, 7
mg/m2 on days 3, 6, and 11) in 99 patients. All donors were 6
antigen HLA-matched sibling (91.4%) or family (8.6%) donors.
Results: There were 103 males and 49 females, with mean age of
Oral Presentations
9BB&MT


Pretransplant recipient blood CD14+ preDC levels correlate with increased acute GVHD after allogeneic PBSC transplantation 

Open Access Repository

Purpose: Thymoglobulin (ATG) given before allogeneic hema-topoietic stem cell transplantation (HSCT) with unrelated donorsreduces acute graft-versus-host disease (GVHD). However, thepossible role of serum concentration of rabbit ATG for the sub-sequent development of acute GVHD after HSCT is unknown.Methods: The serum concentration of rabbit IgG was analyzed byenzyme-linked immunosorbent assasy in 61 patients after unre-lated donor HSCT. Doses of ATG as part of the conditioningranged between 4 and 10 mg/kg. Stem cell source was bonemarrow (BM) in 28 cases and peripheral blood (PBSC) in 33.Conditioning was mainly cyclophosphamide combined with totalbody irradiation (TBI) or busulfan. Most patients received GVHDprophylaxis with cyclosporine and methotrexate. Results: Eventhough we found a good correlation between given ATG dose andserum concentration of rabbit IgG after transplant (r  0.67), therewas a wide variation of rabbit IgG levels within each dose group.After administration, levels of rabbit IgG decreased slowly andcould still be detected up to 5 weeks after HSCT. We found acorrelation between grade of acute GVHD and concentration ofrabbit IgG in serum obtained before transplantation (P  .017).Patients with serum levels of rabbit IgG  70 mg/ml before HSCThad very low risk for developing acute GVHD grades II-IV com-pared with those with  70 mg/ml (11% vs 53%; P  .001).Conclusion: Measuring rabbit IgG levels in patients receivingATG as prophylaxis against GVHD after HSCT may be a helpfultool in decreasing the risk of severe GVHD.24GENERATION OF TOLEROGENIC DENDRITIC CELLS AND REGULATORYT CELLS THROUGH INTRAVENOUS DELIVERY OF AUTOLOGOUS PHO-TOPHERESIS-INDUCED APOPTOTIC CELLSCampbell, K.1; Huber, J.1; Rosenberg, A.1; Peters, C.1; Harriman, G.1;Strobl, F.1; Peritt, D.1; Schwarz, A.2; Maeda, A.2; Schwarz, T.2 1.Therakos, Inc., Exton, PA; 2. University Clinics Schleswig-Holstein,Kiel, Germany.Phagocytosis of apoptotic cells by macrophages or dendritic cellshas been shown to regulate immune responses both in vivo and invitro. Extracorporeal photopheresis (ECP) involves the clinicalreinfusion of peripheral blood leukocytes that are undergoing ap-optosis following exposure ex vivo to 8-methoxypsoralen (8-MOP)and UVA light. ECP is approved for the palliative treatment ofcutaneous T-cell lymphoma and has been reported to have utilityin immune-mediated inflammatory diseases, such as graft-versus-host disease (GvHD) and solid-organ transplant rejection, andautoimmune diseases, such as rheumatoid arthritis and Crohn’sdisease. We have evidence to suggest that ECP therapy may mod-ulate host dendritic cell function and induce regulatory T-cellgeneration. When coincubated with ECP-treated cells, activateddendritic cells produce reduced levels of proinflammatory cyto-kines, such as interleukin-12, whereas transforming growth fac-tor- levels are modestly increased. Activation of CD4 T cells inthe presence of allogeneic dendritic cells and ECP-treated cellspromotes generation of a population of T cells that can suppressproliferation of naive syngeneic T cells, as well as suppress inter-feron- production. To confirm these findings in vivo, we used amurine contact hypersensitivity model. ECP-treated or controlleukocytes from mice sensitized with the hapten dinitrofluoroben-zene (DNFB) were injected intravenously into naive recipients.Compared with controls, mice that received ECP-treated cellsdemonstrated significantly less ear swelling after sensitization andchallenge with DNFB. Suppression of ear swelling was specific forDNFB and was cell-mediated, as demonstrated by the ability totransfer DNFB tolerance to naive mice, which could appropriatelyrespond to the unrelated hapten oxazalone. Transfer of this toler-ance was abrogated by depletion of either CD4 or CD25 T-cellpopulations. Collectively, these results suggest that the delivery ofECP-treated cells promotes generation of regulatory T cells thatare capable of modulating immune responses. Regulatory T cellshave been implicated in the control of GvHD, and as previouslyreported, ECP has demonstrated beneficial activity in GvHD. As aresult, international phase II clinical trials are currently underwayto assess the efficacy of photopheresis in GvHD patients.25PRETRANSPLANT RECIPIENT BLOOD CD14 PREDC LEVELS CORRE-LATE WITH INCREASED ACUTE GVHD AFTER ALLOGENEIC PBSCTRANSPLANTATIONArpinati, M.1; Giannoullia, P.1; Chirumbolo, G.1; Bonifazi, F.1; Saun-thararajah, Y.2; Bandini, G.1; Stanzani, M.1; Baccarani, M.1; Rondelli,D.2 1. Research Center for Transplant Immunology, Institute of Hema-tology, University of Bologna, Bologna, Italy; 2. Section of Hematology/Oncology, University of Illinois at Chicago, Chicago, IL.Host dendritic cells (DCs) present host alloantigens to donor Tlymphocytes. Human peripheral blood contains various circulatingDC precursors including CD11c myeloid preDC (mDC),CD14 monocytic DC precursors (CD14 preDC) and plasma-cytoid preDC (pDC). We used flow cytometry to enumerate bothmDC (lin-, HLA-DR, and CD11c), mono-DC (CD14), andpDC (lin-, HLA-DR, and CD123) numbers in the blood ofpatients receiving an allogeneic HSCT. Fifty consecutive patientsundergoing HSCT from HLA-matched related (n  28) or unre-lated (n  22) donors were enrolled in the study. The stem cellsource was bone marrow in all unrelated donors, and branulocytecolony-stimulating factor (G-CSF) mobilized PBSC in related do-nors. All patients received CsA and MTX as GVHD prophylaxis.Moreover, 26 patients (52%) received ATG before transplant.mDC and pDC PB counts were significantly lower in patients thanin 28 age-matched healthy controls (8.8 cells/l [25th-75th per-centile, 3.5–14.5] mDC, and 2.8 [1.3–5.5] pDC, versus 15.5 [12.1–25.1] and 8.6 [5.6–13.1], respectively; P  .001). However themDC/pDC ratio was significantly higher in the patient group (3.5[1.6–6.2] vs 1.7 [1.3–2.6]; P  .002). CD14 preDC counts werenot significantly different. Among the 46 patients who were evalu-able, 12 (26%) developed acute GVHD grade II-IV. Risk factorssignificantly associated with acute GVHD were older age (P .01), PBSC transplantation (P  .02), and the absence of ATG inthe conditioning regimen (P  .01). Patients with acute GVHDhad significantly higher pretransplantation mDC:pDC ratio (5.7[3.3–16.4] vs 3.1 [1.6–5.5]; P  .03) and CD14 preDC counts(395 [326–625] vs 284 [187–395]; P  .02). A subset analysis wasperformed in PBSC patients, only 3 of whom had received ATGbefore transplant. Among 26 evaluable patients, 10 (38%) devel-oped acute GVHD grade II-IV. Besides older age (P  .02), theonly risk factors significantly associated with acute GVHD inPBSC patients were the pretransplantation mDC:pDC ratio (5.7[4.1–13.1] vs 1.7 [1.2–2.9]; P  .008) and CD14 preDC counts(395 [352–710] vs 259 [199–314]; P  .004). In multivariate anal-ysis, only older age (P  .04) and pretransplantation circulatingCD14 preDC numbers (P  0.04) were significantly associatedwith acute GVHD in PBSC transplants. These findings demon-strate that blood levels of DC precursors may correlate with ahigher risk of developing aGVHD. Future studies will be aimed atdepleting host preDC before allotransplant as a means of GVHDprophylaxis.26ACUTE AND CHRONIC GRAFT-VERSUS-HOST DISEASE (GVHD) IN PA-TIENTS UNDERGOING ALLOGENEIC BMT FOR THALASSAEMIA MAJORGeorge, B.; Mathews, V.; Viswabandhya, A.; Kavitha, N.; Srivastava,A.; Chandy, M. Department of Haematology, Christian Medical College,Vellore, Tamilnadu, India.Methods: Between October 1991 and June 2004, 152 thalasse-mic patients who underwent allogeneic BMT and survived morethan 2 weeks were evaluated for graft-versus-host disease(GVHD). Conditioning regimens included cusulfan (Bu) 16 mg/kg, cyclophosphamide (Cy) 200 mg/kg, and antilymphocyte glob-ulin (ALG) 120 mg/kg (in 91 patients); Bu 600 mg/m2 and Cy 200mg/kg (in 51 patients), Bu 14 mg/kg, Cy 10 mg/kg, and ALG 120mg/kg (in 8 patients), and others (in 2 patients). GVHD prophy-laxis consisted of cyclosporine (CSA) alone in 11 patients, CSA andmethotrexate (MTx) (15 mg/m2 on day 1, 10 mg/m2 on days 3, 6,and 11) in 40 patients and CSA and MTx (10 mg/m2 on day 1, 7mg/m2 on days 3, 6, and 11) in 99 patients. All donors were 6antigen HLA-matched sibling (91.4%) or family (8.6%) donors.Results: There were 103 males and 49 females, with mean age ofOral Presentations9B B & M T

Pretransplant recipient blood CD14+ preDC levels correlate with increased acute GVHD after allogeneic PBSC transplantation

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Pretransplant recipient blood CD14+ preDC levels correlate with increased acute GVHD after allogeneic PBSC transplantation

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