A female patient received a renal transplantation from an unrelated cadaver donor, and five years later developed myelodysplastic syndrome (MDS) with immunological abnormalities. Chromosomal analysis ...showed trisomy 8 in bone marrow cells. FISH analysis indicated that trisomy 8 was present in 4% of CD19 + cells, suggesting that the MDS clone involved B lymphocytes. Polymerase chain reaction of the human androgen receptor gene indicated B cell clonality (54%) and granulocyte clonality (63%). There have been no previous reports of secondary MDS following renal transplantation in which the MDS clone involved the B cell lineage. The abnormal MDS B cell clone may have caused the immunological abnormalities.
Recombinant human erythropoietin (rHu EPO) has been reported to accelerate early erythroid reconstitution after bone marrow transplantation (BMT). We conducted a pilot study on rHu EPO for late-onset ...anemia in 9 patients after allogeneic BMT. The patients achieved initial erythropoietic recovery (hemoglobin (Hb) range 9.1-13.4, mean 10.8 g/dl), but then developed transplant-related anemia (Hb range 6.3-9.7, mean 8.2 g/dl) more than 50 days after BMT. This type of anemia was related to graft-versus-host disease (GVHD), cytomegalovirus infection, and/or impaired EPO secretion. The patients received 3,000 or 12,000 U of rHu EPO subcutaneously three or seven times weekly. Hb levels increased by more than 2 g/dl in 6 of the 9 patients, but were unchanged in the 3 patients with severe GVHD. These findings suggest that in some cases rHu EPO is effective for the treatment of late-onset anemia after BMT.
Three patients with severe aplastic anemia, acute promyelocytic leukemia (M3) and chronic myelogenous leukemia, developed myelodysplastic changes with trilineage morphological abnormalities in a few ...months following allogenic bone marrow transplantation (BMT). Morphologically dysplastic changes associated with moderate-severe anemia, leukopenia and/or thrombocytopenia appeared on day 40, day 62 and day 68 after BMT. A ferrokinetics study clearly showed ineffective erythropoiesis in one patient. Hematopoietic cells were shown to be of donor-origin in all three cases. The levels of vitamin B12 and folic acid were normal. Laboratory tests showed no signs of hemolysis or fragmentation of red blood cells. Although the cause of aberrant hematopoiesis compatible with MDS within 100 days post-BMT remains to be determined, cytomegalovirus infection, ganciclovir and/or graft-versus host disease (GVHD) might be associated with this myelodysplasia following allogeneic BMT.
The involvement of adult T-cell leukemia (ATL) cells in organs such as the skin and lymph nodes is observed in about 50% of cases of ATL. Epstein-Barr virus (EBV) infection has often been observed in ...the clinical course of ATL. In this study, we established two B-cell lines from peripheral blood of patients with ATL. EBV DNA, proviral DNA for HTLV-1 and Tax mRNA were detected in both lines. As part of the characterization of these cells, an enhanced expression of intercellular adhesion molecule-1 (ICAM-1) (CD54) or ICAM-3 (ICAM-3) (CD50), lymphocyte function-1 (LFA-1) (CD11a/CD18), and Mac-1 (CD11b/CD18) was observed. To investigate the role of the interaction of these viruses, we transfected EBV and/or HTLV-1 into a healthy donor's lymphocytes, an EBV-infected B cell line, Raji, and a HTLV-1 negative T-cell line, Jurkat. Enhanced expression of adhesion molecules was also observed in double transfectants (EBV and HTLV-1). In the clinical course of ATL, LMP-1, EBNA-2, CD50 and CD54 were detected in lymph nodes and skin specimens by immunohistochemical staining. Furthermore, high levels of interleukin-4 (IL-4) were detected in these cell lines and transfectants. The results indicated that coinfection with HTLV-1 and EBV may induce aggressive organ involvement through the enhanced expression of adhesion molecules via IL-4 signaling. A new mechanism of ATL involvement is discussed.
We previously reported that all-trans retinoic acid (ATRA) inhibits growth in HTLV-1-positive T-cell lines and fresh cells from patients with adult T-cell leukemia. However, the mechanism of this ...inhibition is not clear. In the present study, we observed that NF-κB transcriptional activity as well as cell growth decreased significantly in HTLV-1-positive T-cell lines in the presence of ATRA. Furthermore, we observed that ATRA reduced HTLV-1 proviral DNA, HTLV-1 genes (gag, tax or pol mRNA) using the real time quantitative polymerase chain reaction. SIL-2R was reduced by ATRA in both protein level (culture supernantant) and mRNA level in HTLV-1-positive T-cell lines. Interestingly, ATRA significantly inhibited RT activity similar to azidothimidine (AZT) in HTLV-1-positive T-cell lines. Moreover, AZT was inhibitory of proviral DNA but not NF-kB transcriptional activity and sIL-2R on HTLV-1, however ATRA was inhibitory of NF-kB, proviral DNA and sIL-2R on HTLV-1. These results suggested that the decrease of sIL-2R induced by ATRA may be caused by the actions of a NF-kB inhibitor acting on the NF-kB/sIL-2R signal pathway. These results suggested that ATRA could have two roles, as a NF-kB inhibitor and as a RT inhibitor.
The complete remission (CR) rate in acute leukemia (AL) has been improved due to progressive chemotherapy. However, relapse frequently occurs as minimal residual disease (MRD). To eradicate MRD, ...immunotherapy using autologous cytotoxic T-lymphocytes has been available. Leukemia cells (LC) of the patients were stored frozen before chemotherapy. Furthermore, after achieving CR, an EBV-transformed lymphoblastoid B-cell line (LCL) was established in each case. To induce Cytotoxic T-lymphocytes (CTL), co-culture system was carried out in two types. One is co-culture of peripheral blood mononuclear cells (PBMCs) and original leukemia cells (LC), the other is co-culture of PBMCs and the patient's own LCL. After co-culture for 5 days, cytotoxic activity was examined by FACS with PKH-26 staining. Interestingly, cytotoxicity against not only autologous LC but the patient's own LCL was observed in almost cases. This phenomenon is called cross-killing. Moreover, regulatory T-cells (Treg) were detected in the effecter phase determined with FACS (CD4+ CD25+) and FOXP3 mRNA by RT-PCR. Enhanced cytotoxicity was observed in inverse relation to a low proportion of Treg. These results suggested that more cytotoxicity may be induced by deletion of the Treg population. In conclusion, cell therapy as an immunotherapy should be useful tool to improve the prognosis, and if stocked LC is not available, CTL activity must be induced by co-culture with the patient's own LCL.
We previously reported that all-trans retinoic acid (ATRA) inhibited growth in HTLV-1-positive T-cell lines and fresh cells from patients with adult T-cell leukemia. Interestingly, ATRA significantly ...inhibited reverse transcriptase (RT) activity similar to azidothimidine (AZT) in HTLV-1-positive T-cell lines. To clarify whether ATRA has an inhibitory effect on the replication of HIV, we examined HIV proviral DNA in a HIV-1-positive cell line (8E5) using real time PCR. ATRA as well as AZT reduced the proviral DNA load of 8E5 in a dose-dependent manner. These results suggest that there is a common element of ATRA signaling in both HTLV-1 and HIV. Furthermore, we examined the effects of ATRA on viral replication in primary lymphocytes of three individuals infected with HIV. ATRA reduced viral replication significantly similar to AZT. These findings suggested that ATRA acts as a RT inhibitor, reducing the HIV-1 proviral DNA load. Finally, we conclude that ATRA may be a potential therapeutic agent for HIV infection.
We previously reported that all-trans retinoic acid (ATRA) inhibits growth in HTLV-1-positive T-cell lines and fresh cells from patients with adult T-cell leukemia. However, the mechanism of this ...inhibition is not clear. In the present study, we observed the NF-κB transcriptional activity as well as cell growth in HTLV-1-positive T-cell lines decreased significantly in these cells in the presence of ATRA. However, no significant growth inhibition was observed after treatment with IFN-γ, TNF-α, and TGF-β of growth inhibitory cytokines induced by ATRA. Thereafter, we observed that ATRA reduced HTLV-1 proviral DNA, gag and tax mRNA load using a real time quantitative polymerase chain reaction and soluble IL-2 receptor in the culture supernatant using ELISA in HTLV-1-positive T-cell lines. Interestingly, ATRA significantly inhibited reverse transcriptase activity similar to azidothymidine in HTLV-1-positive T-cell lines. These results suggested that ATRA could inhibit reverse transcriptase activity in the growth inhibition of ATL cells. Additionally, an effect of ATRA on replication of the human immunodeficiency virus (HIV) was also observed. ATRA significantly reduced the HIV proviral DNA load of both a HIV-1-positive cell line and HIV-1-infected patients. These results indicated that ATRA may be useful for HIV treatment in a clinical setting.
Autoimmune disease in Fas-deficient MRL-Faslpr mice is dependent on infiltrating autoreactive leukocytes and autoantibodies, and IFN-gamma plays an important role in the pathogenesis. As IL-18 is ...capable of inducing IFN-gamma production in T cells, we hypothesized that signaling through IL-18R is involved in the pathogenesis. To investigate the impact of IL-18 in this autoimmune disease, we generated an MRL-Faslpr strain deficient in IL-18Ralpha. Compared with the wild-type strain, IL-18Ralpha-deficient MRL-Faslpr mice survived longer and showed a significant reduction in renal pathology, including glomerular IgG deposits, proteinuria, and serum anti-DNA Abs. Intrarenal transcripts encoding IFN-gamma, TNF-alpha, IL-12, and IL-10, which have been linked to nephritis, were all markedly reduced. Skin lesions, lymphadenopathy, and lung pathology characteristic of the MRL-Faslpr mouse disease were diminished in IL-18Ralpha-deficient MRL-Faslpr mice. Thus, we conclude that IL-18Ralpha signaling is critical to the pathogenesis of autoimmune disease in MRL-Faslpr mice.