Search PubMed⌕ Search

Biomedical subjects

Chi Wha Han

Publications and source records attributed to Chi Wha Han.

3 recordsLinked to original sources

Current status of therapeutic plasma exchange in Korea.

A nationwide survey on the status of plasma exchange in Korea was performed during the 2 year period 2001-02. Data from 496 patients were collected from 15 major hospitals. The most common indication was myasthenia gravis (15.3%), followed by thrombotic thrombocytopenic purpura (14.5%) and hemolytic uremic syndrome (9.7%). Clinical improvement was noted in 70.1% of the 415 cases. Plasma exchange by centrifugation alone accounted for 92.4%. Postcentrifugal filtration was carried out in 5.6% and double filtration in 2.0% of treatments. The most common instruments for the centrifugation were Cobe Spectra (71.3%) and Fenwal CS3000 (15.8%). Filtration was performed by either Kuraray KM8300 or Kuraray KM8800. The overall frequency of complications was 11.1% (293/2647 cases), of which symptomatic hypocalcemia was the most common (2.3%).

Health Care Surveys↗

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-gamma were low in group D. Our results suggest that cotransplantation of MSC in HSCT prevents lethal GVHD, possibly by immune modulation.

Animals↗

Supplemental peripheral blood stem cells to decrease marrow rejection in adult patients with severe aplastic anemia.

Twenty-two multi-transfused patients with a long duration of severe aplastic anemia (SAA) received a transplant from an HLA-matched donor after cyclophosphamide (CY) plus antithymocyte globulin plus procarbazine using CD34(+) enriched blood stem cells + fresh marrow. Peripheral blood stem cells (PBSC) were collected on days 5 and 6 of G-CSF (10 microg/kg/day), and T cells were depleted using an immunoadsorption column (n = 15) or magnetic cell sorting (n = 7). Marrow harvesting was performed 48 hr after the last leukapheresis. Two patients (9.1%) that developed graft failure had a successful engraftment again using unpurged PBSC. Median time to neutrophils > or = 0.5 x 10(9)/l and platelets > or = 20 x 10(9)/l without platelet transfusions were 12 days and 17 days, respectively. Acute graft-versus-host disease (GVHD) grade II occurred in four of 22 patients. No patient developed grade III or IV acute GVHD. Four of the evaluable 21 patients had chronic GVHD. One patient developed extensive disease. Three patients (13.6%) died from CY-induced heart failure, extensive-type chronic GVHD, and sepsis of unknown cause. The Kaplan-Meier estimate of survival was 83.9% (95% CI, 70.1-95.2%) with a median follow-up duration of 33.5 (6-44) months. CD34(+)-enriched PBSC in combination with unmanipulated marrow seem to play a role in overcoming the sensitization to histocompatibility antigens without an apparent increase in GVHD. The stem cell component therapy may be feasible for the high-risk SAA adult patients.

Adolescent↗