The author briefs the main research progress and way of the new developed nonmyeloablative allogeneic stem cell transplantation(NAST).The definition,conditioning regimen ,graft versus host disease(GVHD),graft versus leukemia(GVL) effects and clinical research are disussed.NAST is developed from theories and ideas of tranditional allogeneic stem cell transplantation,is a new way for hematological diseases ,malignant tumors and congenital immunodeficiencies.The author proposes cooperative researches on problems related with NAST.

Objective To explore the clinical significance of allogeneic peripheral stem cell transplantation in the treatment of acute radiation sickness.Methods Two victims were accidentally irradiated by a 60Co source in a nuclear accident in Jining,Shandong province,China in 2004.They were exposed to more than 20-25 Gy(patient A)and 9-15Gy(patient B)of 60Co-ray,and were diagnosed as having developed intestinal form of acute radiation sickness(ARS)and extremely severe bone marrow form of ARS,respectively.After the treatment with the preparative regimens based on low-doses of fludarabine,antilymphocyte globulin and cyclophosphamide,the two patients successfully received HLA-haploidentical(patient A)and HLA-identical(patient B)peripheral blood stem cell transplantation(PBSCT),respectively,7 days after the exposure.Cyclosporin A combined with mycophenolate mofetil was used for the prevention of graft-versus-host disease(GVHD).In addition,bone marrow mesenchymal stem cells from a donor were administered into patient A by intra-bone marrow injection.Results Both peripheral blood and bone marrow examinations showed the recovery of hemopoiesis after PBSCT,and neither patients displayed obvious clinical signs of GVHD.However,patient A died of septicemia and multi-organ failure on day 33 after the exposure,while patient B died of heart failure dominant multi-organ failure on day 75 after the exposure.Conclusions Allogeneic PBSCT is a feasible and effective treatment for ARS,while infection and multi-organ failure are major causes of death of the patients.

Objective To sum up the therapeutic experiences and to analyze the causes of multiple organ dysfunction syndrome (MODS) occurred in a patient who subjected to an accidental 60 Co exposure. Methods The patient was diagnosed as MODS by clinical manifestation, the auxiliary examinations and pathologic autopsy. In therapeutic aspects, intensive care, ventilator-assisted breathing, anti-infection, nutritional support treatment and protection management of important organs were given. Results After a successful transplantation of HLA-identical allogeneic peripheral blood stem cell, the complaints of MODS emerged repeatedly as fever, lung infection, respiratory failure, cardiac arrhythmia, circulatory failure, hepatic injury, decreased urine output and paralytic ileus. At last, the patient died of multi-organ failure 75 days after exposure to radiation. The results of auxiliary examinations showed enlargement of heart and cardiac arrhythmia. Biochemical examination also indicated the increased hyper-sensitive C-reactive protein. The results of pathologic autopsy indicated the existence of fungous infections in whole body, pulmonary fibrosis, myocardium degeneration and necrosis and radiation enteritis. In addition, congestive hepatopathy, renal hemorrhage and intracerebral hemorrhage were also found in the examination. Conclusion Some special clinical features were found in this case, and the cause of MODS is mainly related to radiation injury of important organs, low level of immunity and infection. So the measures of anti-infection and protective treatment of multiple organs should be taken. The key and difficulty for preventing such a kind of MODS might be to improve the patient's immunity and to help the tissue reparation after radiation injury.

Objective To practice the prevention and treatment of severe bone marrow form and intestine form of acute radiation sickness complicated by bacteria infection for providing an effective method on the treatment of acute radiation sickness. Methods Two patients with severe acute radiation sickness suffered from different infection during treatment. Based on their clinical symptoms, image analysis and the findings of microbiological culture, the patients underwent different anti-bacteria and anti-fungi treatment, and the results were evaluated. Result Repeated multiple bacterial infection companied with fungi infection occurred in the two patients with severe acute radiation sickness during the period of treatment. The bacterial infection was controlled temporarily by an intensively antibacterial and antimycotic treatment, but the fungi infection was uncontrolled. In patient A, acute peritonitis occurred 14 days after exposure, and pulmonary infection occurred 19 days after exposure. The pulmonary infection in patient A was controlled by using antibacterial drugs Tienam and Vancocin, while the patient died of multiple organ failure and fungi infection 33 days after exposure. In patient B, pulmonary infection occurred 17 days after exposure, and the septicemia occurred twice with Gram-negative bacteria at 55th day and 71st day after exposure. The pulmonary infection was controlled provisionally by using antibacterial drugs Tienam and Vancocin, while the patient died of multiple organ failure 75 days after exposure. Conclusion The bacterial infection companied with severe acute radiation sickness is phased occurrence. The generalized and phased application of intensive antibiotics might be an effective treatment.

Objective To explore the clinical effects of second non-myeloablative stem cell transplantation (NAST). Methods Six cases of malignant hematological diseases receiving second NAST were retrospectively analyzed. Of them, 3 were suffered from transplant rejection after 1st NAST and the remaining 3 were stable mixed chimerism. Results Five of the patients achieved complete donor's chimerism and have been in disease-free-survival for 6～27 months. 1 GVHD occurred in only one of the 6 patients, and no transplant-related death happened. Conclusion Second NAST is effective for the treatment of patients with transplant rejection,and is also rational choice for those patients with refractory or relapse malignant hematological diseases.

Objective To summarize the experimence of nonmyeloablative allogeneic peripheral blood cell transplantation in the treatment of chronic leukemia. Methods Seven patients, including 6 cases of chronic myeloid leukemia (in chronic phase), one of chronic lymphoid leukemia (in third stage), with HLA-identical siblings donor received allogeneic peripheral blood stem cell transplantation after a nonmyeloablative conditioning. Results All of them were engrafted with donor cells (4 with full of donor cells grafted, 3 with mixed chimerism) and recovered hematopoiesis (WBC recovered to more than 0.5 ?10 9/L during postoperative 9 day to 21 day and platelet recovered to more than 30?10 9/L during postoperative 11 day to 28 day). One of them developed a GVHD of degree IV. One of them developed aGVHD of degree I. Conclusion This procedure is much safe, effective and of less complications than the myeloablative condioning regimens and may represent another new approach in the management of patients with chronic leukemia.

This paper investigate the methods to detect engraftment rate of the four patients with hematological disorders who accepted nonmyeloablative allogeneic peripheral blood stem cell transplantation(NAPBSCT). To find out the best method, their engraftment rates were detected serially at different time after NAPBSCT by means of either FISH, or conventional chromosome analysis combined with R banding analysis concurrently.The results were carefully compared with one another. All these four sex mismatched cases were engrafted partially,and two of them changed to full engrafment. The results show no statistically significant difference in 3 groups (conventional method, FISH for hypermetaphase, FISH for interphase nuclei). But the results strongly indicate that FISH is a rapid, precise, objective,and reliable menthod for detection of the engraftment rate,and it is suitable for sex mismatched NAPBSCT.

To evaluate the effects of donor stem cell infusion (DSI) in patients after nonmyeloablative allogeneic peripheral blood stem cell transplantation( NAPBSCT),6 patients were infused donor stem cell in+7d～+90d consisting of MNC (0.6～7.6)?10 8 /kg, CD34 + cells (0.3～3.4)?10 6 /kg,CD3 + cells (0.3～5.1)?10 8 /kg.The results showed that 5/6 patients had definite effects in promoting donor chimeras after DSI,of these 3 achieved full donor chimeras following mixed chimeras ;4/6 have graft versus leukemia(GVL)effects.No hematopoiesis aplasia was found, and only one Ⅳdegree aGVHD developed related with DSI. It was concluded that DSI have definite GVL effects and can convert mixed chimeras to full chimeras without causing GVHD and severe hematopoietic aplasia.

This paper investigate the methods to detect engraftment rate of the four patients with hematological disorders who accepted nonmyeloablative allogeneic peripheral blood stem cell transplantation(NAPBSCT). To find out the best method, their engraftment rates were detected serially at different time after NAPBSCT by means of either FISH, or conventional chromosome analysis combined with R-banding analysis concurrently.The results were carefully compared with one another. All these four sex-mismatched cases were engrafted partially,and two of them changed to full engrafment. The results show no statistically significant difference in 3 groups (conventional method, FISH for hypermetaphase, FISH for interphase nuclei). But the results strongly indicate that FISH is a rapid, precise, objective,and reliable menthod for detection of the engraftment rate,and it is suitable for sex-mismatched NAPBSCT.

Objective To investigate the effects of recombinant human granulocyte colonystimulating factor(G-CSF) on murine thymic emigration and subsets reconstitution after a sublethal dose of irradiaton.Methods Female BALB/c mice were irradiated with a 6.0 Gy of γ-ray total-body irradiation and then randomly divided into GCSF group and control group.For mice in the GCSF group,recombinant human G-CSF 100 μg · kg-1 · d-1 was injected subcutaneously once daily for 14 continuous days and mice in the control group were given the same volume of phosphate buffered solution (PBS).At 7,14,21 and 28 days later,mice were killed and thymus mononuclear cell suspension were analyzed by flow cytometry for the percentage of the four stages of thymic CD4 -CD8 - double negative cells (DN1-4) and the CD4 + CD8 + double positive ( CD4 + CD8 + DP),CD4 + CD8 - single positive ( CD4 + SP),CD4 -CD8 + single positive cells (CD8 + SP).Real-time PCR was used for detection and quantitation of murine T cell receptor rearrangement excision circles(sjTRECs) of the thymic cells of 30 and 60 d after irradiation.Results The percentage of thymic DN1 cells in GCSF group was significantly higher than that of the control group 7 d after irradiation (t =9.59,P ＜ 0.05 ).21 d later,the proportion of thymic DN3 and DN4 cells were higher than those of the control group ( t =16.37,7.6,P ＜ 0.05 ).The percentage of thymic CD4 + CD8 + DP cells decreased 7 d after irradiation,increased at 14 d,decreased again at 21 days,and then got a permanent recover.The percentage of thymic CD4 + CD8 + DP cells in the GCSF group recovered to normal and was significantly higher than that of the control group 28 days after irradiation (t =12.22,P＜ 0.05).The percentage of thymic CD8 + SP cells of the GCSF group was significantly higher than that of the control group 21 d after irradiation ( t =3.77,P ＜ 0.05 ),while G-CSF had no obvious influence on the percentage of the thymic CD4 + SP cells.The sjTRECs copies in the GCSF group was significantly higher than that of the control group 30 d after irradiation ( t =5.95,P ＜ 0.01 ),which disappeared 60 d later.Conclusions G-CSF could promote the proliferation and differentiation of thymic DN and DP cells,enhance the recent thymic emigrants and accelerate central immunologic reconstitution after acute irradiation.