No abstract

Gastric bleeding due to graft-vs-host-disease (GVHD) is rare after allogeneic hematopoietic stem cell transplantation, and the interrelationship between endoscopic and histologic assessment has not been well studied. Four patients with documented gastric bleeding due to GVHD were evaluated retrospectively. The endoscopic findings varied markedly and included mild mucosal edema with focal erythema, diffuse erythema with mucosal oozing, and diffuse polypoid indurations with multiple bleeding ulcerations. The histologic features of endoscopic biopsy specimens also varied from scattered apoptotic epithelial cells in one end to denudation of the epithelium with crypt necrosis in the other. The endoscopic findings could not accurately predict the histologic grading of GVHD. Nevertheless, gastric bleeding resolved in 3 patients with increasing intensity of immunosuppression. There was significant disparity between the endoscopic and histologic assessment of the severity of GVHD, and careful adjustment of immunosuppressive therapy might be warranted.

Both bone marrow hematopoietic cells (BM-HCs) and mesenchymal stem cells (BM-MSCs) may have cytogenetic aberrations in leukemic patients, and anti-leukemic therapy may induce cytogenetic remission of BM-HCs. The impact of anti-leukemic therapy on BM-MSCs remains unknown. Cytogenetic studies of BM-MSCs from 15 leukemic patients with documented cytogenetic abnormalities of BM-HCs were investigated. To see the influence of anti-leukemic therapy on BM-MSCs, cytogenetic studies were carried out in seven of them after the completion of anti-leukemic therapy, including anthracycline/Ara-C-based chemotherapy in two patients, high-dose busulfan/cyclophosphamide-based allogeneic transplantation in two patients, and total body irradiation (TBI)-based allogeneic transplantation in three patients. To simulate the effect of TBI in vitro, three BM-MSCs from one leukemic patient and two normal adults were irradiated using the same dosage and dosing schedule of TBI and cytogenetics were re-examined after irradiation. At the diagnosis of leukemia, two BM-MSCs had cytogenetic aberration, which were completely different to their BM-HCs counterpart. After the completion of anti-leukemic therapy, cytogenetic aberration was no longer detectable in one patient. Unexpectedly, BM-MSCs from three patients receiving TBI-based allogeneic transplantation acquired new, clonal cytogenetic abnormalities after transplantation. Similarly, complex cytogenetic abnormalities were found in all the three BM-MSCs exposed to in vitro irradiation. In conclusion, anti-leukemic treatments induce not only "cytogenetic remission" but also new cytogenetic abnormalities of BM-MSCs. TBI especially exerts detrimental effect on the chromosomal integrity of BM-MSCs and highlights the equal importance of investigating long-term adverse effect of anti-leukemic therapy on BM-MSCs as opposed to beneficial effect on BM-HCs.

BackgroundCD4+interferon (IFN)-γ+ T cell (Th1) and CD4+interleukin (IL)-4+ T cell (Th2) polarizations are crucial in the pathogenesis of graft-versus-host disease (GVHD). However, this hypothesis is largely based on animal experiments of Parent-into-F1 GVHD model. The causal relationship between kinetics of Th1, Th2 and associated cytokines and the clinical activity of GVHD in a real world situation remains unknown.MethodologyPeripheral blood was collected every week prospectively from Day 0 to Day 210 (patients without GVHD) or Day 300 (patients with chronic GVHD) after allogeneic peripheral blood stem cell transplantation in consecutive 27 patients. The frequencies of Th1 and Th2 within CD4+ T cells were determined by flow cytometry and pplasma IFN-γ, IL-12, IL-4, and IL-10 were determined by ELISA.Principal FindingsKinetics of Th1, Th2 frequency, and the plasma IL-10 and IFN-γ more commonly coincided with, rather than predicted, the activity of GVHD. These markers are significantly higher when acute or chronic GVHD developed. The kinetics of IL-10 is especially correlated well with the activity of GVHD during clinical course of immunosuppressive treatment. For patients with hepatic GVHD, there is a positive correlation between plasma IL-10 levels and the severity of hepatic injury. The frequency of Th2 is also significant higher in acute GVHD and tends to be higher in chronic GVHD. Interestingly, there is a very good positive correlation between the frequency of Th1 and Th2 (r = 0.951, p<0.001). The plasma level of IL-4 and IL-12 are not associated with the activity of GVHD.ConclusionsThe frequency of Th1, Th2 within CD4+ T cells and plasma IL-10 and IFN-γ are good biomarkers of GVHD. Plasma IL-10 can also be used to monitor the therapeutic responsiveness. Furthermore, both Th1 and Th2 likely contribute to the pathogenesis of GVHD.