Chi Wha Han

Cotransplantation of Marrow Stromal Cells May Prevent Lethal Graft-versus-Host Disease in Major Histocompatibility Complex Mismatched Murine Hematopoietic Stem Cell Transplantation

Marrow stromal cells (MSC) produce a microenvironment supporting hematopoiesis and may contribute immune tolerance because of low immunogenicity and the suppressive effect of alloreactivity. We investigated whether cotransplantation of MSC could prevent lethal graft-versus-host disease (GVHD) in major histocompatibility complex mismatched allogeneic murine hematopoietic stem cell transplantation (HSCT) using female BALB/c (H-2d, recipient) and C3H/He (H-2k, donor) mice. MSC were obtained from C3H/He bone marrow cells (BMC). MSC and irradiated BALB/c splenocytes (SP) were cocultured with C3H/He SP or BMC. Nonirradiated MSC did not inhibit the proliferation of alloantigen-stimulated BMC and SP. However, irradiated MSC suppressed the proliferation of alloantigen-stimulated SP at a level comparable with that of immunosuppressive agents, and the suppression by MSC was reversed to a significant degree by interleukin 2. Lethally irradiated BALB/c mice received transplants of donor cells according to the following experimental groups (group A, BMC only; group B, BMC and SP; group C, BMC, SP, and MSC; group D, BMC and MSC). The survival rate in group D was higher than in the other groups (P =.0057), and the clinical GVHD scores and serum levels of interferon-γ were low in group D. Our results suggest that cotransplantation of MSC in HSCT prevents lethal GVHD, possibly by immune modulation.

[Hepatitis B virus reactivation during chlorambucil and prednisolone treatment in an HBsAg-negative and anti-HBs-positive patient with B-cell chronic lymphocytic leukemia].

It is generally accepted that seroconversion of hepatitis B virus (HBV) surface antigen (HBsAg) to an antibody to HBsAg (anti-HBs) indicates clearance of HBV. Here we report a case of severe hepatitis that manifested during chemotherapy in a female patient with chronic lymphocytic leukemia (CLL) who had been initially seronegative for HBsAg and seropositive for anti-HBs. The patient received chlorambucil and prednisolone for the treatment of CLL. After 6 months the serum levels of aminotransferases were increased, and HBsAg and HBV DNA were present in serum. Lamivudine was administered immediately after confirming the HBV reactivation, which considerably improved jaundice and aminotransferase levels after 3 weeks. The patient was able to resume the chemotherapy whilst continuing lamivudine treatment. This case report highlights the need for physicians to be aware of the potential risk of HBV reactivation even in an HBsAg-negative person but with detectable anti-HBc and/or anti-HBs, underscoring the need for future studies that explore the role of antiviral prophylaxis in this setting.