Chronic GVHD (cGVHD) is a main cause of late death and morbidity after allogeneic hematopoietic cell transplantation, but its pathogenesis remains unclear. We investigated the roles of Th subsets in cGVHD with the use of a well-defined mouse model of cGVHD. In this model, development of cGVHD was associated with up-regulated Th1, Th2, and Th17 responses. Th1 and Th2 responses were up-regulated early after BM transplantation, followed by a subsequent up-regulation of Th17 cells. Significantly greater numbers of Th17 cells were infiltrated in the lung and liver from allogeneic recipients than those from syngeneic recipients. We then evaluated the roles of Th1 and Th17 in cGVHD with the use of IFN-γ-deficient and IL-17-deficient mice as donors. Infusion of IFN-γ(-/-) or IL-17(-/-) T cells attenuated cGVHD in the skin and salivary glands. Am80, a potent synthetic retinoid, regulated both Th1 and Th17 responses as well as TGF-β expression in the skin, resulting in an attenuation of cutaneous cGVHD. These results suggest that Th1 and Th17 contribute to the development of cGVHD and that targeting Th1 and Th17 may therefore represent a promising therapeutic strategy for preventing and treating cGVHD.

PEGs and polysorbates are found in many pharmaceuticals, cosmetics, and foods (1, 2). We report the first patient with anaphylaxis caused by PEGs and polysorbate 80 that were cross-reactive with hydroxyethyl starch.A 33-year-old man had undergone surgery for lumbar disc herniation. He went into anaphylactic shock a few minutes after the application of povidone-iodine gel to the dead space resulting from the surgery. He was successfully treated with intravenous corticosteroids and adrenaline. He reported a history of wheezing after using shampoo containing phenothirin. We performed prick tests with the constituents of the povidone-iodine gel and the phenothirin shampoo. A negative saline control and a positive histamine (10 mg/ml) control test were included. The positive wheal was 7 × 5 mm, and the negative

Goals of Work:Oral and systemic infections arising from the oral cavity are significant problems in clinical management of patients undergoing leukemia treatment. However, there is significant disparity in the reported incidences of development of periodontal infections.Evidence is limited to those showing the systemic influence of periodontal infection in neutropenic patients. This study indicated an association between febrile neutropenia (FN) and periodontitis in a case in which periodontal treatment in the intervals between chemotherapy cycles reduced FN in subsequent courses of chemotherapy and hematopoietic transplantation (HCT). Patient and Methods:Periodontal treatment was performed in a 61-year-old man with advanced periodontitis, who received HCT following 3 cycles of chemotherapy. After recovery from neutropenia induced by initial chemotherapy, periodontal treatment was performed in each chemotherapy interval period. Following extraction of teeth with severe advanced periodontitis, all teeth were subjected to periodontal pocket curettage and root planing, which are common periodontal treatments to reduce periodontal pockets harboring anaerobic periodontal bacteria, before HCT. Main Results:Periodontal treatment successfully reduced periodontal pockets from 4.1±1.5 mm to 3.0±0.6 mm, which was almost within the healthy range (<3.0 mm), before HCT. The frequency of FN decreased significantly with increasing cycles of chemotherapy, and decreases in FN corresponded to progress of periodontal treatment. Blood cultures obtained a total of 12 times throughout leukemia treatment were all negative. 3 Conclusions:The observations reported here indicate the importance of periodontal treatment in clinical management of patients undergoing leukemia treatment to prevent FN, although all blood cultures were negative.

Chronic graft-versus-host disease (GVHD) remains a major late complication of allogeneic bone marrow transplantation (BMT). In a previous study, impaired thymic negative selection of the recipients permitted the emergence of pathogenic T cells that cause chronic GVHD using MHC class II-deficient (H2-Ab1 KO) B6 into C3H model and CD4(+) T cells isolated from chronic GVHD mice caused chronic GVHD when administered into the secondary recipients. In this study, we evaluated the kinetics of regulatory T cell (Treg) reconstitution in wild type B6 into C3H model. After myeloablative conditioning, host Tregs disappeared rapidly, followed by expansion of Tregs derived from the donor splenic T cell inoculum. However, the donor splenic T cell-derived Treg pool contracted gradually and was almost completely replaced by newly generated donor bone marrow (BM)-derived Tregs in the late post-transplantation period. Next, we compared the effects of cyclosporine (CSA) and mammalian target of rapamycin (mTOR) inhibitors on Treg reconstitution. Administration of CSA significantly impaired Treg reconstitution in the spleen and thymus. In contrast, BM-derived Treg reconstitution was not impaired in mTOR inhibitor-treated mice. Histopathological examination indicated that mice treated with CSA, but not mTOR inhibitors, showed pathogenic features of chronic GVHD on day 120. Mice treated with CSA until day 60, but not mTOR inhibitors, developed severe chronic GVHD followed by adoptive transfer of the pathogenic CD4(+) T cells isolated from H2-Ab1 KO into C3H model. These findings indicated that long-term use of CSA impairs reconstitution of BM-derived Tregs and increases the liability to chronic GVHD. The choice of immunosuppression, such as calcineurin inhibitor-free GVHD prophylaxis with mTOR inhibitor, may have important implications for the control of chronic GVHD after BMT.

A liver allograft recipient developed acute-type adult T-cell leukemia (ATL) during tacrolimus treatment, 2 years after undergoing transplantation for subacute fulminant hepatitis. Both donor and recipient were asymptomatic carriers of human T-cell lymphotropic virus type I (HTLV-I), but the ATL cells originated from the recipient. Tacrolimus treatment was discontinued, and combination chemotherapy was administered. The patient achieved complete remission, but the transplanted liver was acutely and chronically rejected. The patient did not respond to rescue therapy with tacrolimus, prednisolone, and mycophenolate mofetil and died of hepatic failure. Liver biopsies showed CD4+ ATL cell infiltration at the onset of ATL but not at the terminal stage. Moreover, Southern blotting revealed clonal integration of HTLV-I into the host genome of lymphoma cells at onset but not at the terminal stage. ATL after liver transplantation has not been previously described. The clinical course of the posttransplantational ATL was atypical, because it did not progress after the onset of rejection.

We conducted a retrospective analysis to evaluate the impact on clinical outcomes of adding rituximab to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) treatment for diffuse large B-cell lymphoma (DLBCL) patients in Japan. A propensity score method was used to compensate for the non-randomized study design. From January 2000 to December 2004, 378 patients who were newly diagnosed with DLBCL at 13 institutes were enrolled: 123 in the rituximab plus CHOP-based chemotherapy (R+) group, and 255 in the CHOP-based chemotherapy only (R-) group. The complete response rate was significantly higher in the R+ group than in the R- group (77.7 vs. 69.4%, P < 0.001). The progression-free survival (PFS) at 2 years was 62.4% in the R+ group and 57.0% in the R- group. The 2-year overall survival (OS) was 76.9% for the R+ group and 70.5% for the R- group. A multivariate analysis revealed that the addition of rituximab was a strong independent prognostic factor for PFS (hazard ratio 0.64, 95% CI 0.43-0.96, P = 0.031). A subgroup analysis revealed that R+ particularly benefited younger patients (hazard ratio 0.25, 95% CI 0.08-0.75, P = 0.013). IPI also showed significant impact for PFS (hazard ratio 1.82, 95% CI 1.55-2.14 for one score increase, P < 0.001) as well as OS (hazard ratio 2.10, 95% CI 1.71-2.57, P < 0.001). In summary, the addition of rituximab to CHOP-based chemotherapy results in better outcomes for Japanese DLBCL patients, particularly younger patients.

727 Chronic graft-versus-host disease (cGVHD) remains a major cause of late death and morbidity after allogeneic hematopoietic cell transplantation, and the treatment of cGVHD remains challenging. All-trans retinoic acid (ATRA), a potent derivative of vitamin A, can regulate immune responses. Am80, which has biological activity approximately 10 times more potent than that of ATRA by binding to RARα and RARβ, but not RARγ, also reduces the severity and progression of immune disease models, including contact dermatitis, collagen-induced arthritis, allergic encephalomyelitis, and atherosclerosis models. Am80 has been reported to suppress the differentiation of Th17 and Th1 cells. Previously, we demonstrated that the administration of ATRA or Am80, significantly decreased skin fibrosis and alopecia, a dominant feature of cutaneous cGVHD, using a well-characterized experimental model of cGVHD: B10.D2 (H−2d) → BALB/c (H−2d). Flow cytometry analysis of the peripheral lymph nodes (PLNs) on day 16 showed significant reductions in Th1, Th17, and Foxp3+ regulatory T cells (Tregs) in Am80-treated recipients, as compared to controls, whereas no reduction in Th2 cells was observed (Nishimori et al., 2009 ASH). To further investigate the roles of Th17 cells and other Th subsets (Th1 and Th2) in cGVHD, we first assessed the kinetics of Th cytokines in the B10.D2 (H-2d) → BALB/c (H-2d) model of cGVHD, which reflects the clinical and pathological symptoms of human cGVHD. BALB/c mice were subjected to sublethal irradiation (6.75 Gy) and injected with 8 × 106 T-cell-depleted bone marrow cells and 8 × 106 spleen cells or 2 × 106 CD90+ spleen T cells from B10.D2 mice. In the early phase (day 14) of post bone marrow transplant (BMT), donor T cells produced significantly less IL-17 in the PLNs of recipients in allogeneic BMT than in syngeneic BMT (1.68±0.09% vs. 4.30±0.53%, p<0.01), while in the late phase (day 28) donor T cells that produced IL-17 were increased significantly in allogeneic recipients, compared with syngeneic controls (7.76±0.27% vs. 1.61±0.16%, p < 0.005). Both IL-17−/IFN-γ+ and IL-17/IFN-γ double positive cells (Th17/Th1 cells) were constantly detected more frequently in allogeneic recipients (p<0.05). Next, we evaluated whether Th17 contributes in a model utilizing IL-17-deficient mice on a B10.D2 background as donor mice; these mice were backcrossed for more than six generations from the original knock-out (KO) mice. Upon transfer of IL-17−/− B10.D2 donor T cells in allogeneic BMT models, skin cGVHD was significantly ameliorated, as compared to recipients of wild-type (WT) T cells, as shown in Figure (p=0.02). Histopathological examination of the skin showed significantly reduced cGVHD pathology in recipients of IL-17−/− donors (3.17±1.09 vs. 8.50±0.84, p=0.006). Flow cytometry analysis of the PLNs, mesenteric lymph nodes (MLNs), and spleen cells in the early phase (day 14) showed no differences in Th1, Th2, and Tregs, while recipients of IL-17−/− had significantly fewer Th1 (p<0.05) and Th17/Th1 (p<0.01) cells on day 35. Furthermore, IFN-γ deficient mice on a B10.D2 background were also backcrossed from the original KO mice and cGVHD was evaluated. BMT from IFN-γ−/− donors significantly improved the clinical cGVHD score, compared with WT donors (p<0.05). Allogeneic recipients given anti-IFN-γ mAb (500 μg/mouse) on days 0, 5, 10, and 15 post BMT had significantly less severe cGVHD, compared with control antibody recipients (p<0.05). Taken together, Th17, especially in the late-chronic phase, and Th1 contribute to the development of cGVHD by promoting the production of proinflammatory cytokines. Targeting Th17 and Th1 may be a promising strategy for preventing and treating cGVHD. Disclosures: No relevant conflicts of interest to declare.

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