OBJECTIVETo establish the mouse model for the expression of PD-L1 by hydrodynamic injection and to study the effects of myeloablative conditioning on hydrodynamic injection-mediated PD-L1 expression.

METHODSPlasmid amplification, hydrodynamic injection, collagenase perfusion, real time PCR, ELISA and flow cytometry were applied to test the expression and function of PD-L1. Also, animal models were set up to test the effects of chemical or radiactive myeloablative conditioning on hydrodynamic injection-mediated PD-L1 expression.

RESULTSThe expression of PD-L1 mRNA and protein could be detected as early as 8 h after hyrodynamic injection and reached peak expression by 24 h, and returned to baseline level by 7 d after injection. Serum PD-L1 level reached to 100 µg/ml as early as 24 h after injection and plateaued at 7 d after injection. Serum PD-L1 persisted for 3 weeks and declined to baseline after 1 month of hydrodynamic injection. The PD-L1 function induced by hydrodynamic injection was consistent with literature reports. At each time point, the PD-L1 expression was not different significantly between the myeloablative conditioning group and control group; the mice transfected with PD-L1 showed a higher survival rate than that in control group.

CONCLUSIONMyeloablative conditioning does not affect hydrodynamic injection-mediated PD-L1 expression, indicating that the PD-L1 can be used in HSCT mouse model.

Animals ; B7-H1 Antigen ; pharmacology ; Disease Models, Animal ; Flow Cytometry ; Hydrodynamics ; Injections ; Mice ; Myeloablative Agonists ; pharmacology ; RNA, Messenger ; Transfection ; Transplantation Conditioning

Immunoglobulin (Ig) D multiple myeloma (MM) accounts for 2% of all MM cases and has been reported to be associated with poor prognosis compared with other MM subtypes. The aim of the present study was to compare the effects of high-dose melphalan treatment and autologous stem cell transplantation (ASCT) on the survival of patients with IgD MM and patients with other MM subtypes. Between November 1998 and January 2005, a total of 77 patients with MM who underwent ASCT at the Asan Medical Center were enrolled in this study. High-dose melphalan (total 200 mg/m2) was used as high-dose chemotherapy. The study population was divided into two groups based on MM subtype: those with IgD MM; and those with other MM subtypes. A total of 8 patients with IgD MM were identified, accounting for about 10% of the study population. Thirty-six patients (47%) had IgG MM, 17 patients (22%) had IgA MM, and 16 patients (20%) had free light-chain MM. The two groups were similar in baseline characteristics. The median follow-up was 17 months and the median overall survival (OS) was 39 months. In the IgD MM group, median eventfree survival (EFS) and OS were 6.9 and 12 months, respectively. In the patients with other MM subtypes, median EFS and OS were 11.5 and 55.5 months (p=0.01, p<0.01), respectively. Multivariate analysis of all patients identified IgD subtype (p=0.002) and Southwest Oncology Group (SWOG) stage 2 or greater at the time of ASCT (p=0.01) as adverse prognostic factors for survival. In this small study at a single center in Korea, patients with IgD MM had poorer outcomes after ASCT than did patients with other MM subtypes.
Adult ; Aged ; Female ; Humans ; Immunoglobulin D/*chemistry ; Male ; Melphalan/*pharmacology ; Middle Aged ; Multiple Myeloma/*drug therapy/genetics/*immunology ; Myeloablative Agonists/*pharmacology ; Prognosis ; Retrospective Studies ; Stem Cell Transplantation/*methods ; Transplantation, Autologous ; Treatment Outcome

BACKGROUND: To compare the mobilizing effects and toxicities of two different doses of cyclophosphamide (CY) plus lenograstim (glycosylated G-CSF), we performed a prospective randomized study by enrolling patients suffering with either high-risk Non-Hodgkin's lymphoma (NHL) or breast cancer undergoing ablative chemotherapy. METHODS: The NHL patients received 4 cycles of CHOP and the breast cancer patients received 2-3 cycles of FAC (FEC) adjuvant chemotherapy. Then, the patients were randomly allocated to receive CY 4 g/m2 (arm A) or 1.5 g/m2 (arm B) in combination with lenograstim. Large volume leukapheresis was carried out and it was continued daily until the target cell dose of 2x10 (6) CD34+ cell/kg was reached. RESULTS: Twenty-seven patients were enrolled in the study. The median number of leukaphereis sessions actually performed was 2.5 sessions in arm A and 3 sessions in arm B. The target cell dose was obtained with the median number of one leukapheresis session in both arms of the study (p=0.09). The collected number of CD34+ cells in the leukapheresis products was higher in arm A than arm B (22.4 vs. 9.9x10 (6) /kg, respectively, p=0.05). Grade III or IV leukopenia was present in 14/15 patients (94%) in arm A and in 1/12 patients (8%) in arm B (p< 0.0001). Grade III or IV thrombocytopenia was present in 8/15 patients (54%) in arm A, but this was not present in any patients of arm B (p=0.0004). Neutropenic fever occurred in 6/15 patients (40%) in arm A, and in 1/12 patients (8%) in arm B (p=0.09). The hematological recovery of the leukocytes and platelets after transplantation was not statistically different between the two doses. CONCLUSION: Low-dose CY plus lenograstim is a safe and effective mobilizing regimen.
Transplantation Conditioning ; Stem Cells/*drug effects ; Recombinant Proteins/administration & dosage/pharmacology ; Prospective Studies ; Myeloablative Agonists/*administration & dosage/pharmacology ; Middle Aged ; Male ; Lymphoma, Non-Hodgkin/*drug therapy ; Leukapheresis ; Humans ; *Hematopoietic Stem Cell Mobilization ; Granulocyte Colony-Stimulating Factor/*administration & dosage/pharmacology ; Female ; Drug Therapy, Combination ; Cyclophosphamide/*administration & dosage/pharmacology ; Chemotherapy, Adjuvant ; Breast Neoplasms/*drug therapy ; Adult