Risk factors for graft-versus-host-disease after donor lymphocyte infusion following T-cell depleted allogeneic stem cell transplantation.

Introduction: Unmodified donor lymphocyte infusions (DLI) after allogeneic stem cell transplantation (alloSCT) can boost the beneficial Graft-versus-Leukemia (GvL) effect but may also induce severe Graft-versus-Host-Disease (GvHD). To improve the balance between GvL and GvHD, it is crucial to identify factors that influence the alloreactivity of DLI. Methods: We investigated the effects of the presence of patient-derived antigen-presenting cells at time of DLI as estimated by the bone marrow (BM) chimerism status, lymphopenia as measured by the absolute lymphocyte count (ALC) at time of DLI, and the presence of a viral infection (de novo or reactivation) close to DLI on the risk of GvHD after DLI. The cohort consisted of patients with acute leukemia or myelodysplastic syndrome who prophylactically or pre-emptively received DLI as standard care after alemtuzumab-based alloSCT. In patients at high risk for relapse, DLI was administered at 3 months after alloSCT (n=88) with a dose of 0.3x106 or 0.15x106 T cells/kg in case of a related or unrelated donor, respectively. All other patients (n=76) received 3x106 or 1.5x106 T cells/kg, respectively, at 6 months after alloSCT. Results: For both DLIs, patients with reduced-intensity conditioning and an unrelated donor had the highest risk of GvHD. For DLI given at three months, viral infection within 1 week before and 2 weeks after DLI was an additional significant risk factor (hazard ratio (HR) 3.66 compared to no viral infection) for GvHD. At six months after alloSCT, viral infections were rare and not associated with GvHD. In contrast, mixed BM chimerism (HR 3.63 for ≥5% mixed chimerism compared to full donor) was an important risk factor for GvHD after DLI given at six months after alloSCT. ALC of <1000x106/l showed a trend for association with GvHD after this DLI (HR 2.05 compared to ≥1000x106/l, 95% confidence interval 0.94-4.45). Furthermore, the data suggested that the presence of a viral infection close to the DLI at three months or ≥5% mixed chimerism at time of the DLI at six months correlated with the severity of GvHD, thereby increasing their negative impact on the current GvHD-relapse-free survival. Conclusion: These data demonstrate that the risk factors for GvHD after DLI depend on the setting of the DLI.

Prophylactic versus Preemptive modified donor lymphocyte infusion for high-risk acute leukemia after allogeneic hematopoietic stem cell transplantation: a multicenter retrospective study.

Donor lymphocyte infusion (DLI) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) has been widely used in preventing post-transplant relapse. We conducted this study to compare the superiority of prophylactic modified DLI (pro-DLI) and preemptive modified DLI (pre-DLI) in patients with high-risk relapse features acute leukemia. Pro-DLI was performed in 95 patients, whereas the pre-DLI cohort included 176 patients. In the pre-DLI cohort, 42 patients relapsed without chance for pre-DLI while 95 patients remained CR without detectable minimal residual disease (MRD). Thirty-nine patients in the pre-DLI cohort became minimal MRD positive/mixed chimerism and received pre-DLI. Pro-DLI cohort had higher 3-year progression-free-survival (PFS) (63.4%vs.53.0%, P = 0.026) and overall survival (OS) (65.2% vs. 57.0%, P = 0.14) compared to the pre-DLI cohort. The 3-year cumulative incidence of relapse (CIR) was 25.3% in the pro-DLI cohort which was significantly lower than 36.7% in the pre-DLI cohort (P = 0.02). The cumulative incidence of grade III-IV aGVHD, cGVHD and non-relapse mortality were comparable between cohorts. Multivariable analysis demonstrated strong protective effect of pro-DLI on OS (hazard ratio (HR) = 0.63, P = 0.04), PFS (HR = 0.54, P = 0.005) and CIR (HR = 0.50, P = 0.005). In high-risk patients with acute leukemia, early scheduled pro-DLI rather than pre-DLI after detectable MRD would reduce post-transplant relapse and improve long-term survival.

The graft-versus-leukemia effect of prophylactic donor lymphocyte infusions after allogeneic stem cell transplantation is equally effective in relapse prevention but safer compared to spontaneous graft-versus-host disease.

Therapeutic donor lymphocyte infusions (tDLI) are used to reinforce the graft-versus-leukemia (GvL) effect in relapse after allogeneic stem cell transplantation (alloSCT). In contrast, the role of prophylactic DLI (proDLI) in preventing leukemia relapse has been less clearly established, although supported by retrospective, case-control, and registry analyses. We report a prospective, monocentric, ten year cohort of patients with high risk acute leukemias (AL) or myelodysplasia (MDS) in whom proDLI were applied beyond day +120 post alloSCT to compensate for lack of GvL.272 consecutive allotransplanted AL or MDS patients in complete remission and off immunosuppression at day +120 were stratified according to the prior appearance of relevant GvHD (acute GvHD °II-IV or extensive chronic GvHD) as a clinical indicator for GvL. Escalating doses of unmodified proDLI were applied to 72/272 patients without prior relevant GvHD. Conversely, 157/272 patients with prior spontaneous GvHD did not receive proDLI, nor did 43/272 patients with contraindications (uncontrolled infections, patient refusal, DLI unavailability).By day 160-landmark analysis (median day of first DLI application), proDLI recipients had significantly higher five-year overall (OS) and disease free survival (DFS) (77% and 67%) than patients with spontaneous GvHD (54% and 53%) or with contraindications (46% and 45%) (p=0.003). Relapse incidence for patients with proDLI (30%) or spontaneous GvHD (29%) was significantly lower than in patients with contraindications (39%; p=0.021). With similar GvHD incidence beyond day +160, non-relapse mortality (NRM) was less with proDLI (5%) than without proDLI (18%; p=0.036).In conclusion, proDLI may be able to compensate for lack of GvL in alloSCT recipients with high risk AL or MDS.

Azacitidine, lenalidomide and donor lymphocyte infusions for relapse of myelodysplastic syndrome, acute myeloid leukemia and chronic myelomonocytic leukemia after allogeneic transplant: the Azalena-Trial.

Azacitidine (Aza) combined with donor lymphocyte infusions (DLI) is an established treatment for relapse of myeloid malignancies after allogeneic transplantation. Based on its immunomodulatory and anti-leukemic properties we considered Lenalidomide (Lena) to act synergistically with Aza/DLI to improve outcome. We, therefore, prospectively investigated tolerability and efficacy of this combination as first salvage therapy for adults with post-transplant relapse of acute myeloid leukemia, myelodysplastic syndromes and chronic myelomonocytic leukemia. Patients were scheduled for eight cycles Aza (75 mg/m2 day 1-7), Lena (2.5 or 5 mg, days 1-21) and up to three DLI with increasing T-cell dosages (0.5×106-1.5×107 cells/kg). Primary endpoint was safety, while secondary endpoints included response, graft-versus-host disease (GvHD) and overall survival (OS). Fifty patients with molecular (52%) or hematological (48%) relapse of myelodysplastic syndromes (n=24), acute myeloid leukemia (n=23) or chronic myelomonocytic leukemia (n=3) received a median of seven (range, 1-8) cycles including 14 patients with 2.5 mg and 36 with 5 mg Lena daily dosage. Concomitantly, 34 patients (68%) received at least one DLI. Overall response rate was 56% and 25 patients (50%) achieved complete remission being durable in 80%. Median OS was 21 months and 1-year OS rate 65% with no impact of type of or time to relapse and Lena dosages. Treatment was well tolerated indicated by febrile neutropenia being the only grade ≥3 non-hematologic adverse event in >10% of patients and modest acute (grade 2-4 24%) and chronic (moderate/severe 28%) GvHD incidences. In summary, Lena can be safely added to Aza/DLI without excess of GvHD and toxicity. Its significant anti-leukemic activity suggests that this combination is a novel salvage option for post-transplant relapse (clinicaltrials gov. Identifier: NCT02472691).

Pre-emptive and prophylactic donor lymphocyte infusion following allogeneic stem cell transplantation.

Donor lymphocyte infusion (DLI) is an allogenic immunotherapy used after allogeneic hematopoietic stem cell transplantation. DLI takes advantage of the graft-versus-tumor effect induced by the infused CD3 + T cells, but may induce graft-versus-host disease. To date, DLI has been attempted to prevent hematological relapse after allogeneic hematopoietic stem cell transplantation in patients with mixed chimerism and molecular relapse (pre-emptive DLI), and as maintenance therapy in patients with high-risk hematological malignancies (prophylactic DLI). DLI response and efficacy depend on patient, disease, and DLI factors. This review discusses the efficacy and risks of DLI, with a focus on pre-emptive and prophylactic use.

Feasibility, safety, and efficacy of early prophylactic donor lymphocyte infusion after T cell-depleted allogeneic stem cell transplantation in acute leukemia patients.

Prophylactic donor lymphocyte infusion (DLI) starting at 6 months after T cell-depleted allogeneic stem cell transplantation (TCD-alloSCT) can introduce a graft-versus-leukemia (GvL) effects with low risk of severe graft-versus-host-disease (GvHD). We established a policy to apply low-dose early DLI at 3 months after alloSCT to prevent early relapse. This study analyzes this strategy retrospectively. Of 220 consecutive acute leukemia patients undergoing TCD-alloSCT, 83 were prospectively classified to have a high relapse risk and 43 were scheduled for early DLI. 95% of these patients received freshly harvested DLI within 2 weeks of the planned date. In patients transplanted with reduced intensity conditioning and an unrelated donor, we found an increased cumulative incidence of GvHD between 3 and 6 months after TCD-alloSCT for patients receiving DLI at 3 months compared to patients who did not receive this DLI (0.42 (95%Confidence Interval (95% CI): 0.14-0.70) vs 0). Treatment success was defined as being alive without relapse or need for systemic immunosuppressive GvHD treatment. The five-year treatment success in patients with acute lymphatic leukemia was comparable between high- and non-high-risk disease (0.55 (95% CI: 0.42-0.74) and 0.59 (95% CI: 0.42-0.84)). It remained lower in high-risk acute myeloid leukemia (AML) (0.29 (95% CI: 0.18-0.46)) than in non-high-risk AML (0.47 (95% CI: 0.42-0.84)) due to an increased relapse rate despite early DLI.

A Multicenter Phase 2 Clinical Trial of 10-Day Decitabine, Dose-Escalated Donor Lymphocyte Infusion, and Ruxolitinib for Relapsed Acute Myeloid Leukemia and Myelodysplastic Syndromes after Allogeneic Hematopoietic Cell Transplantation.

Post-transplantation relapse of acute myeloid leukemia and myelodysplastic syndromes has a poor prognosis. Donor lymphocyte infusion (DLI) is one treatment approach. However, efficacy is limited, and toxicity, mostly in the form of acute graft-versus-host disease (GVHD), is frequent. We tested a novel approach using 10-day decitabine, dose-escalated DLI, and ruxolitinib in a multicenter phase 2 trial aimed at increasing the efficacy of DLI and reducing its toxicity. Up to four 28-day cycles were administered. The primary endpoint was 6-month overall survival (OS). Of the 14 patients who started cycle 1, 13 received 1 DLI, 6 received 2 DLIs, and 1 received 3 4 DLIs. A preplanned interim analysis after enrolling 14 patients suggested futility, and the trial was closed to accrual. The final analysis showed a 6-month OS of 36% (95% confidence interval [CI], 18 to 72), a 1-year progression-free survival of 7% (95% CI, 1% to 47%), a 6-month cumulative incidence of grade II-IV acute GVHD of 57% (95% CI, 26% to 80%), and a 1-year nonrelapse mortality of 14% (95% CI, 2% to 38%). The combined modality treatment studied in this trial was ineffective and did not reduce DLI toxicity.

Comparison of the effect of DLI according to cell sources in relapsed AML after allogeneic stem cell transplantation.

For relapsed acute myeloid leukemia (AML) patients who received allogeneic hematopoietic stem cell transplantation, donor lymphocyte infusion (DLI) is an effective therapy. However, the cell source of DLI remains a topic of debate. In this study, we aimed to compare the efficacy and safety of G-CSF mobilized cells (G-DLI) with conventionally collected DLI (C-DLI). A total of 81 patients (50 C-DLI vs. 31 G-DLI) were assessed for clinical outcomes. There were no statistically significant differences in the baseline characteristics between the two groups including AML risk, donor types, interval from relapse to DLI, and infused CD3+ cell count. Although not statistically significant, complete remission (CR) and chimerism conversion rates were higher in G-DLI than in C-DLI: 51.6% vs. 28.0%, P = 0.057 and 42.3% vs. 28.2%, P = 0.363, respectively. There was no difference in acute graft-versus-host disease (GVHD) incidence and severity of acute GVHD between the two groups. The median overall survival (OS) of the G-DLI and C-DLI groups was 139 days and 106 days, respectively (P = 0.58). In conclusion, G-DLI appears to be a safe and an equally efficacious substitute for C-DLI, which is more readily available.

Donor lymphocyte infusions after haploidentical stem cell transplantation with PTCY: A study on behalf of the EBMT cellular therapy & immunobiology working party.

Donor lymphocyte infusion (DLI) is a treatment option to prevent or treat relapse after allogeneic hematopoietic cell transplantation (HCT). We here report data for 173 patients who received one or multiple DLIs after haploidentical-HCT with post-transplant cyclophosphamide (PTCY) at 47 EBMT centers from 2009 to 2018. Indication for DLI was: prophylactic for 59 (34.3%), preemptive for 20(11.6%), and therapeutic for 93(54.1%). For the prophylactic group, the median number of DLIs was 1 (IQR:1-2.5) with a median first dose of 0.1 × 106 CD3+ T cell/kg, for the preemptive 2 (IQR:1-3) with 0.5 × 106 CD3+ T cell/kg, for the therapeutic 1 (IQR:1-3) with 1 × 106CD3+ Tcell/kg, respectively. OS after first DLI was 61% (46-75%) for prophylactic, 40% (19-61%) for preemptive, and 22% (13-31%) for therapeutic. CI of II-IV aGVHD and cGVHD was 17% (7-27%) and 53% (40-67%) for the prophylactic, 20% (2-38%) and 21% (3-39%) for the preemptive, 17% (9-24%) and 24% (15-33%) for the therapeutic group, respectively. Our data show great variability in the indications and modalities of DLI across responding EBMT centers. Survival rates remain relatively low in patients with active disease. While the cumulative incidence of aGVHD appears acceptable, we showed a high incidence of cGVHD in the prophylactic group, compared with preemptive and therapeutic DLI. These data should be investigated further in prospective clinical trials.

Healthy-like CD4+ Regulatory and CD4+ Conventional T-Cell Receptor Repertoires Predict Protection from GVHD Following Donor Lymphocyte Infusion.

Donor lymphocyte infusion (DLI) can (re-)induce durable remission in relapsing patients after allogeneic hematopoietic stem-cell transplantation (alloHSCT). However, DLI harbors the risk of increased non-relapse mortality due to the co-occurrence of graft-versus-host disease (GVHD). GVHD onset may be caused or accompanied by changes in the clonal T-cell receptor (TCR) repertoire. To investigate this, we analyzed T cells in a cohort of 21 patients receiving DLI after alloHSCT. We performed deep T-cell receptor ß (TRB) sequencing of sorted CD4+CD25+CD127low regulatory T cells (Treg cells) and CD4+ conventional T cells (Tcon cells) in order to track longitudinal changes in the TCR repertoire. GVHD following DLI was associated with less diverse but clonally expanded CD4+CD25+CD127low Treg and CD4+ Tcon TCR repertoires, while patients without GVHD exhibited healthy-like repertoire properties. Moreover, the diversification of the repertoires upon GVHD treatment was linked to steroid-sensitive GVHD, whereas decreased diversity was observed in steroid-refractory GVHD. Finally, the unbiased sample analysis revealed that the healthy-like attributes of the CD4+CD25+CD127low Treg TCR repertoire were associated with reduced GVHD incidence. In conclusion, CD4+CD25+CD127low Treg and CD4+ Tcon TRB repertoire dynamics may provide a helpful real-time tool to improve the diagnosis and monitoring of treatment in GVHD following DLI.

A retrospective single-center analysis of G-CSF-mobilized donor lymphocyte infusion in hematologic malignancies after unmanipulated allogenic PBSCT.

To explore the efficacy and safety of G-SCF-mobilized donor lymphocyte infusion (DLI) for treatment of relapse of hematologic malignancies after allogeneic peripheral blood stem cell transplantation, we performed a retrospective analysis in a cohort of patients with morphologic (n = 36) or molecular (n = 22) relapse post transplantation. The 3-year post-DLI survival rates for therapeutic and preemptive DLI recipients were 16.7% and 33.3%, respectively. The occurrence of DLI-associated acute graft-versus-host disease predicted longer survival, whereas diagnosis of T cell acute lymphoblastic leukemia/lymphoma or myelodysplastic syndromes or early relapse after transplant (< 6 months) predicted shorter survival after therapeutic DLI. Cumulative incidence of progression to hematologic relapse and non-relapse mortality after preemptive DLI were 46.8% and 29.1%, respectively. Active disease prior to transplant and early molecular relapse after transplant (< 4 months) were the strongest predictors of non-relapse mortality after preemptive DLI. In conclusion, although therapeutic DLI had limited efficacy against T cell acute lymphoblastic leukemia/lymphoma or myelodysplastic syndromes or early post-transplant relapse, patients who developed DLI-associated acute graft-versus-host disease would benefit from this procedure in the setting of G-SCF-mobilized DLI. Furthermore, preemptive DLI could protect half of patients from hematologic relapse after transplantation with acceptable toxicity.

Long-term results and GvHD after prophylactic and preemptive donor lymphocyte infusion after allogeneic stem cell transplantation for acute leukemia.

We report on 318 patients with acute leukemia, receiving donor lymphocyte infusion (DLI) in complete hematologic remission (CHR) after allogeneic stem cell transplantation (alloSCT). DLI were applied preemptively (preDLI) for minimal residual disease (MRD, n = 23) or mixed chimerism (MC, n = 169), or as prophylaxis in high-risk patients with complete chimerism and molecular remission (proDLI, n = 126). Median interval from alloSCT to DLI1 was 176 days, median follow-up was 7.0 years. Five-year cumulative relapse incidence (CRI), non-relapse mortality (NRM), leukemia-free and overall survival (LFS/OS) of the entire cohort were 29.1%, 12.7%, 58.2%, and 64.3%. Cumulative incidences of acute graft-versus-host disease (aGvHD) grade II-IV°/chronic GvHD were 11.9%/31%. Nineteen patients (6%) died from DLI-induced GvHD. Age ≥60 years (p = 0.046), advanced stage at transplantation (p = 0.003), shorter interval from transplantation (p = 0.018), and prior aGvHD ≥II° (p = 0.036) were risk factors for DLI-induced GvHD. GvHD did not influence CRI, but was associated with NRM and lower LFS/OS. Efficacy of preDLI was demonstrated by decreasing MRD/increasing blood counts in 71%, and increasing chimerism in 70%. Five-year OS after preDLI for MRD/MC was 51%/68% among responders, and 37% among non-responders. The study describes response and outcome of DLI in CHR and helps to identify candidates without increased risk of severe GvHD.

Pro-Resolving Factors Released by Macrophages After Efferocytosis Promote Mucosal Wound Healing in Inflammatory Bowel Disease.

Nonresolving inflammation is a critical driver of several chronic inflammatory diseases, including inflammatory bowel diseases (IBD). This unresolved inflammation may result from the persistence of an initiating stimulus or from the alteration of the resolution phase of inflammation. Elimination of apoptotic cells by macrophages (a process called efferocytosis) is a critical step in the resolution phase of inflammation. Efferocytosis participates in macrophage reprogramming and favors the release of numerous pro-resolving factors. These pro-resolving factors exert therapeutic effects in experimental autoimmune arthritis. Here, we propose to evaluate the efficacy of pro-resolving factors produced by macrophages after efferocytosis, a secretome called SuperMApo, in two IBD models, namely dextran sodium sulfate (DSS)-induced and T cell transfer-induced colitis. Reintroducing these pro-resolving factors was sufficient to decrease clinical, endoscopic and histological colitis scores in ongoing naive T cell-transfer-induced colitis and in DSS-induced colitis. Mouse primary fibroblasts isolated from the colon demonstrated enhanced healing properties in the presence of SuperMApo, as attested by their increased migratory, proliferative and contractive properties. This was confirmed by the use of human fibroblasts isolated from patients with IBD. Exposure of an intestinal epithelial cell (IEC) line to these pro-resolving factors increased their proliferative properties and IEC acquired the capacity to capture apoptotic cells. The improvement of wound healing properties induced by SuperMApo was confirmed in vivo in a biopsy forceps-wound colonic mucosa model. Further in vivo analysis in naive T cell transfer-induced colitis model demonstrated an improvement of intestinal barrier permeability after administration of SuperMApo, an intestinal cell proliferation and an increase of α-SMA expression by fibroblasts, as well as a reduction of the transcript coding for fibronectin (Fn1). Finally, we identified TGF-ß, IGF-I and VEGF among SuperMApo as necessary to favor mucosal healing and confirmed their role both in vitro (using neutralizing antibodies) and in vivo by depleting these factors from efferocytic macrophage secretome using antibody-coated microbeads. These growth factors only explained some of the beneficial effects induced by factors released by efferocytic macrophages. Overall, the administration of pro-resolving factors released by efferocytic macrophages limits intestinal inflammation and enhance tissue repair, which represents an innovative treatment of IBD.

Graft-versus-mastocytosis effect after donor lymphocyte infusion: Proof of principle.

Advanced systemic mastocytosis is a relatively rare entity where allogeneic stem cell transplantation can lead to the cure of the disease in selected patients. Delayed incomplete responses with graft-versus-mastocytosis effect were published in a few cases. In this particular patient's report, we describe the direct evidence and potency of graft-versus-mastocytosis effect of donor lymphocyte infusions in a patient with systemic mastocytosis with associated hematological neoplasm (SM-AHN). In a 53-year-old female patient, an allogeneic stem cell transplantation after conventional induction treatment was performed for transformed acute myeloid leukemia (AML) during the course of polycythemia vera. After 6 years of remission period of AML and PV, the patient developed aleukemic mast cell leukemia and JAK2-positive myeloproliferative neoplasm (SM-AHN). We were able to achieve a sustained complete remission of SM-AHN lasting for 6 years with only donor lymphocyte infusions in a status of mixed chimerism. The patient is in a good clinical condition and remission. The potent graft-versus-mastocytosis effect in this patient resembles the favorable effect of donor lymphocyte infusions in relapsing chronic myeloid leukemia patients after transplantation. This patient is, to our knowledge, the first case showing the proof of principle of graft-versus-mastocytosis effect.

Clinical effects of administering leukemia-specific donor T cells to patients with AML/MDS after allogeneic transplant.

Relapse after allogeneic hematopoietic stem cell transplantation (HCT) is the leading cause of death in patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS). Infusion of unselected donor lymphocytes (DLIs) enhances the graft-versus-leukemia (GVL) effect. However, because the infused lymphocytes are not selected for leukemia specificity, the GVL effect is often accompanied by life-threatening graft-versus-host disease (GVHD), related to the concurrent transfer of alloreactive lymphocytes. Thus, to minimize GVHD and maximize GVL, we selectively activated and expanded stem cell donor-derived T cells reactive to multiple antigens expressed by AML/MDS cells (PRAME, WT1, Survivin, and NY-ESO-1). Products that demonstrated leukemia antigen specificity were generated from 29 HCT donors. In contrast to DLIs, leukemia-specific T cells (mLSTs) selectively recognized and killed leukemia antigen-pulsed cells, with no activity against recipient's normal cells in vitro. We administered escalating doses of mLSTs (0.5 to 10 × 107 cells per square meter) to 25 trial enrollees, 17 with high risk of relapse and 8 with relapsed disease. Infusions were well tolerated with no grade >2 acute or extensive chronic GVHD seen. We observed antileukemia effects in vivo that translated into not-yet-reached median leukemia-free and overall survival at 1.9 years of follow-up and objective responses in the active disease cohort (1 complete response and 1 partial response). In summary, mLSTs are safe and promising for the prevention and treatment of AML/MDS after HCT. This trial is registered at www.clinicaltrials.com as #NCT02494167.

Occurrence and Severity of Donor Lymphocyte Infusion-Associated Chronic Graft-versus-Host Disease Influence the Clinical Outcomes in Relapsed Acute Leukemia after Allogeneic Hematopoietic Stem Cell Transplantation.

The aim of this study was to investigate the occurrence and severity of chemotherapy plus donor lymphocyte infusion (Chemo-DLI)-associated chronic graft-versus-host disease (cGVHD) in a consecutive cohort of patients with acute leukemia who experienced relapse after allogeneic hematopoietic stem cell transplantation (n = 104). The 5-year cumulative incidence of complete remission after Chemo-DLI was 81.0% (95% CI, 73.3% to 88.7%) and 84.6% (95% CI, 74.5% to 94.7%) in the moderate and severe cGVHD groups, respectively, which was significantly higher than that of the mild cGVHD group at 40.9% (95% CI, 29.3% to 52.5%) and non-cGVHD group at 29.2% (95% CI 23.1% to 35.3%). The cumulative incidence of nonrelapse mortality was comparable between patients with and without cGVHD. The 5-year probabilities of progression-free survival after Chemo-DLI were 42.9% (95% CI, 26.2% to 70.2%) and 34.6% (95% CI, 15.3% to 78.2%) in the moderate and severe cGVHD groups, respectively, which were both significantly higher than those of the mild cGVHD group at 9.1% (95% CI, 2.4% to 34.1%) and non-cGVHD group at 8.3% (95% CI 3.3% to 21.3%). The 5-year probabilities of overall survival after Chemo-DLI were 56.7% (95% CI, 38.9% to 82.7%) and 43.1% (95% CI, 22.1% to 84.0%) in the moderate and severe cGVHD groups, respectively, which were both significantly higher than those of the mild cGVHD group at 9.1% (95% CI 1.8% to 47.1%) and non-cGVHD group at 14.9% (95% CI, 7.3% to 30.2%). Our observations highlight the close relationship between cGVHD and immune-mediated graft-versus-leukemia (GVL) effect in patients with relapse receiving Chemo-DLI; however, mild cGVHD may not be associated with a sufficiently strong GVL effect to induce remission and improve survival.

Basiliximab treatment of severe GVHD induced by donor lymphocyte infusion with interferon-a.

The development of acute graft-versus-host-disease (GVHD) in recipients of donor lymphocyte infusion (DLI) is not rare and the complication is quite often fatal. We describe a severe skin GVHD patient who responded well to basiliximab. A 20-year-old male who received a hematopoietic stem cell transplantation at his age of 18. His fusion gene Aml1/Eto remained positive, so he was administered with DLI combined with interferon-a (IFN-a). Forty days after the therapy, he presented with severe skin rashes with multiple mucous membrane involvement. The skin and mucous lesions recovered after basiliximab treatment. So far, severe type of erythema multiforme in GVHD patients after DLI with IFN-a injection is firstly reported here, together with a new alternative therapy.

PD-1 deficiency augments bone marrow failure in a minor-histocompatibility antigen mismatch lymphocyte infusion model.

Although PD-1 blockade has revolutionized cancer immunotherapy, immune-related adverse events (irAEs) present life-threatening complications. Recent reports of aplastic anemia (AA) as irAEs implicate PD-1/PD-L1 as important in preventing immune-mediated destruction of the hematopoietic niche. Infusion of PD-1-deficient (PD-1 knockout [KO]) lymph node (LN) cells into minor-antigen mismatched mice resulted in early mortality, as well as more severe bone marrow (BM) hypoplasia, anemia, and BM microarchitecture disruption in PD-1 KO LN-infused mice relative to mice that received B6 LN cell infusion. Mice that received PD-1 KO LN cells had more CD8+ T-cell infiltration of the BM and greater expansion of H60-specific CD8+ T cells than did their B6 LN-infused counterparts. In the spleen, CD8+ T cells were skewed to an effector memory phenotype, suggesting accelerated differentiation of PD-1 KO T cells. Our data suggest that PD-1 dysregulation has a role in murine BM failure and vigilance in irAE monitoring may be desirable to treat early AA and related cytopenias.

Immune Reconstitution Inflammatory Syndrome After DLI in a SCID Patient After Hematopoetic Stem Cell Transplantation.

Immune reconstitution inflammatory syndrome (IRIS) is a clinical condition emerging after immune recovery of an immunocompromised status, mostly in human immunodeficiency virus infected patients but also in several other settings, such as the recovery from the severe combined immunodeficiency status after hematopoietic stem cell transplantation. Herein, we report a patient transplanted for severe combined immunodeficiency who developed IRIS for 2 times, namely shortly after transplantation and after donor lymphocyte infusion. Pediatric transplant teams need to be aware of the previous IRIS phenomenon of BCG-adenitis while making the decision of donor lymphocyte infusions.