联合成骨细胞移植促进骨髓移植小鼠的造血功能重建

目的 探讨联合成骨细胞移植对骨髓移植小鼠造血功能重建的影响.方法 Balb/c小鼠60只,取其中18只制备移植用骨髓有核细胞和成骨细胞.将其余42只小鼠分为3组.单纯移植组:小鼠18只,仅进行骨髓移植(BMT);联合移植组:18只,进行BMT的同时每只小鼠输入成骨细胞2×106个;正常对照组:小鼠6只,不做任何处理,仅作为移植前的正常对照.移植组小鼠在全身照射(TBI)预处理后4 h经尾静脉注入骨髓细胞2×106个.移植后第7、14和21天,分别处死移植组小鼠6只,对小鼠的外周血细胞和骨髓单个核细胞(BMMNC)进行计数,采用流式细胞术测定BMMNC中CD34+细胞的百分比,使用HPIAS-1000高清晰度彩色病理图像系统测量骨髓造血组织面积,采用免疫组化染色法测定骨髓组织微血管密度(MVD).结果 移植后第7天,单纯移植组和联合移植组小鼠外周血细胞计数及BMMNC数均明显低于正常对照(P＜0.01).第21天时联合移植组小鼠白细胞、红细胞及BMMNC数明显恢复,血小板数已接近正常对照组;单纯移植组小鼠外周血细胞数和BMMNC数虽然有所恢复,但其恢复程度明显弱于联合移植组.移植后第7、14和21天,联合移植组外周血细胞计数及BMMNC数均明显高于同期单纯移植组(P＜0.01或P＜0.05).移植后第7、14、21天,单纯移植组和联合移植组小鼠骨髓造血组织面积、BMMNC中CD34+细胞百分比及骨髓组织MVD均明显低于正常对照组(P＜0.01),但联合移植组均高于同期单纯移植组(P＜0.01或P＜0.05).结论 联合成骨细胞移植能有效促进骨髓移植小鼠骨髓造血系统的重建.

Abstract：

Objective To explore the effects of cotransplantation with osteoblasts on hematopoietic reconstitution in mice after bone marrow transplantation (BMT). Methods The typical model of syngeneic BMT was established. 18 Balb/c mice were used to prepare the bone marrow nuclear cells and osteoblasts for BMT. The 42 Balb/c mice were randomly divided into 3 group:normal group (6 mice, without any treatment), the single BMT group ( 18 mice, given 2 × 106 bone marrow nuclear cells/each mouse) and the cotransplantation group of HSC with osteoblaats (18 mice,given 2 × 106 bone marrow nuclear cells and osteoblasts/each mouse). The following factors were measured on day 7, 14, 21 after BMT: peripheral blood cells, bone marrow mononuclear cells (BMMNC), the percentage of CD34+ cells in BMMNC (assayed by flow cytometry), the hematopoietic tissue changes (detected by HPIAS-1000 image analysis system) and micro vascular density (MVD) of bone marrow tissue (with immunohistochemistry). Results The levels of periphral WBC, RBC, PLT, BMMNC in the contransplantation group were higher than those in the single BMT group (P＜0. 01 or P＜0. 05). In the contransplantation group, the percentage of CD34+ cells in BMMNC, the hematopoietic tissue area and the MVD of bone marrow were also higher than the single BMT group on the 7th, 14th, 21st day after BMT(P＜0.01 or P＜0.05). Conclusion Cotransplantation with osteoblasts could significantly promote hematopoietic reconstruction in mice after BMT. Cotransplantation may represent a promising means of achieving higher engraftment rate after BMT.     

归芪合剂在小鼠骨髓移植后造血重建中的作用

目的探讨归芪合剂对小鼠骨髓移植后造血重建的影响。方法将BALB/c小鼠随机分为骨髓移植对照组(对照组)和骨髓移植归芪治疗组(归芪组)。对照组和归芪组的小鼠骨髓移植后,立即分别经胃饲生理盐水和归芪合剂0.4 ml,2次/d,直至小鼠处死为止。移植后第7、14、21 d时分别处死小鼠,计数其外周血白细胞、红细胞、血小板及骨髓单个核细胞,并作骨髓组织学观察。采用半定量逆转录聚合酶链反应(RT-PCR)和免疫组织化学方法检测小鼠骨髓单个核细胞CD44 mRNA基因的表达水平和骨髓组织中CD44的蛋白表达水平。结果归芪组骨髓移植后第7、14、21 d外周血细胞和骨髓单个核细胞计数,骨髓组织造血面积及巨核细胞计数,骨髓CD44 mRNA和蛋白表达水平均显著高于对照组(P<0.05或P<0.01)。结论归芪合剂能促进小鼠骨髓移植后骨髓造血重建,其机制可能是通过增强骨髓粘附分子CD44的表达水平实现的。     

Mycobacterial infections in marrow transplant patients

Bone marrow transplant recipients undergo ablation of host immune defenses with total-body irradiation or high dose chemotherapy, or both. Over a 5.6-year period, mycobacterial infections were observed in 7 of 682 patients with leukemia who received marrow grafts. Four patients had pulmonary and three extrapulmonary infection. Granulomas were observed in the lungs of three patients, in the liver of one patient, and in the skin of one patient. Cultures revealed Mycobacterium tuberculosis in two patients, Mycobacterium fortuitum in two patients, and Mycobacterium kansasii in one patient. In the six patients treated with antimycobacterial therapy in either the pretransplant or posttransplant period, complete resolution of the infection was achieved. Pretransplant chest radiograph abnormalities suggesting mycobacterial infections should be aggressively evaluated in these immunocompromised hosts. Prophylaxis should be considered in marrow graft recipients with a well-established history of inadequately treated tuberculosis, previous Bacille Calmette-Guerin immunotherapy, known family contacts, recent skin test conversion, or past skin test positivity.     

HSCT联合不同剂量内皮祖细胞输注对小鼠造血重建的影响

目的 探讨异基因造血干细胞移植联合不同剂量内皮祖细胞(EPC)输注对移植后造血重建的影响.方法 以C57BL/6小鼠为供鼠,Balb/c小鼠为受鼠,进行HSCT,输注骨髓单个核细胞数量为5×106个/只.仅进行HSCT者为单纯骨髓细胞移植组;行HSCT的同时经尾静脉输注供者骨髓单个核细胞诱导培养的EPC的受鼠为EPC联合移植组,EPC的输注量分别为5×104、1×105、5× 105和1×106个/只.另设正常对照组和致死量照射组.观察小鼠的存活率、造血重建情况及骨髓微环境的变化.结果 各EPC联合移植组小鼠存活时间长于单纯骨髓移植组,5×105 EPC联合移植组至观察结束时存活率为100％,高于其他各组(P＜0.05).移植后10和15 d,5×105 EPC联合移植组外周血白细胞数量高于其他组(P＜0.05).移植后15 d,5×105 EPC联合移植组外周血血小板数量高于其他组(P＜0.05).5×105 EPC联合移植组造血组织增生程度也好于其他组.5×105 EPC联合移植组骨髓内HSC比例为(1.06±0.03)％,高于其他各组(P＜0.05).结论 小鼠异基因骨髓移植中联合输注5×105 EPC能够有效促进造血重建,提高小鼠存活率.     

Pharmacokinetics of 15-deoxyspergualin studied in renal transplant patients receiving the drug during graft rejection

The pharmacokinetics of the novel immunosuppressant 15-deoxyspergualin (DSG) were studied in five renal transplant patients who participated in a dose-finding study for the treatment of renal graft rejection. DSG, in a dose of 4 or 6 mg/kg per day, was given in a 3-h i.v. infusion for 5 days, in combination with a 4-day course of i.v. methylprednisolone. Analyses of DSG in plasma and urine were performed by highperformance liquid chromatography (HPLC). Plasma samples were taken up to 12 h following infusion on treatment day 2 and again on day 4 or 5. Urine was collected during the infusion and up to 12 h following the infusion. DSG was rapidly eliminated from the plasma in an apparently biexponential manner. The mean t1/2alpha was 0.5 h (range 0.1–1.1 h) and the mean t1/2 beta 2.4 h (range 1.0–5.9 h). The mean Cmax was 4117 ng/ml (range 1944–7166 ng/ml) and the mean AUC 12505 ng·ml^-1·h (range 5642–24435 ng·ml^-1·h). Clerance ranged from 375 to 945 ml/min (mean 653 ml/min) and volume of distribution ranged from 0,2 to 1,4 l/kg (mean 0,7 l/kg). A small fraction (mean 1.6%, range 0.1%–2.7%) of the DSG dose given was excreted unmetabolized in the urine. The amount of DSG in the urine correlated strongly to renal function (P=0.0019). Pharmacokinetics were otherwise not affected by the degree of renal function. There were no significant differences in the pharmacokinetic determinants and no accumulation of the drug on study day 4 or 5, as compared to day 2. Therefore, the drug can safely be given to patients with impaired renal function. DSG did not affect cyclosporin pharmacokinetics.     

Chronic cyclosporine-associated nephrotoxicity in bone marrow transplant patients

This study describes the prevalence and degree of chronic cyclosporine-associated nephropathy and its risk factors. For this purpose we reviewed all available renal histology specimens in 169 bone marrow transplant recipients treated during an eight year period with cyclosporine for prevention of graft-versus-host-disease, and determined their pattern and degree of histomorphological changes. A total of 51 specimens obtained from 49 patients by biopsy (n = 12) or autopsy (n = 39) was evaluated. The pattern of histomorphological changes was compared with diagnosis, age, sex, and potential risk factors--such as cyclosporine dose, levels, duration of therapy, changes in serum creatinine and onset of hypertension. Morphological lesions of chronic cyclosporine-associated nephropathy were found in 67% of the specimens. They were more frequent and more severe with increasing duration of cyclosporine therapy, in patients with a higher increase in serum creatinine during the first 3 months and in patients given total-body irradiation for conditioning. These latter findings suggest that additional damage sensitizes the kidney to irreversible toxic effects of cyclosporine.     

Acceleration of the hemopoietic reconstitution in mice undergoing bone marrow transplantation by recombinant human granulocyte colony-stimulating factor.

We have investigated the effects of recombinant human granulocyte colony-stimulating factor (rG-CSF) on hemopoietic reconstitution after bone marrow transplantation (BMT) following lethal irradiation in mice. Mice received a daily administration of 10 micrograms/kg rG-CSF or control vehicle one through 21 days after BMT. Spleen colony-forming units (CFU-S), granulocyte-macrophage colony-forming units (CFU-GM), megakaryocyte colony-forming units (CFU-Meg), and erythroid burst-forming units (BFU-E) increased in both bone marrow and spleen of the rG-CSF-treated mice as compared with the control. This increase was evident during the administration period. In spite of the increase in the progenitor cells in bone marrow and spleen, only a recovery of neutrophils was accelerated in peripheral blood. Thus rG-CSF accelerated granulopoietic recovery in the BMT mice, with an enhanced recovery of the stem cells and the progenitors for erythrocytes and megakaryocytes. These results indicate the potential clinical usefulness of rG-CSF in the treatment of patients undergoing BMT.     

Gonadal dysfunction and infertility in kidney transplant patients receiving sirolimus

Sirolimus is an immunosupressor of the mammalian target of rapamycin inhibitors (mTOR-I) group. Recent studies have emphasized a potential impact of sirolimus on male gonadal function. We report our clinical experience with sirolimus-induced gonadal dysfunction and infertility in both male and female kidney transplant patients. Of the 170 kidney transplant patients, nine (5.3%) patients (six males and three females) were receiving sirolimus. Follow-up data for two male patients were not available. The one unmarried female patient developed amenorrhea post-transplantation and had resumption of her menstrual cycles after discontinuation of sirolimus. The remaining six married patients (four males and two females), who all had fathered or conceived children in the pre-transplantation period, developed gonadal dysfunction and infertility on average 5–12 months after transplantation. Sirolimus was discontinued in all four male patients with full recovery of the oligo/azospermia and restoration of fertility. Both married female patients developed amenorrhea post-transplantation. Sirolimus was discontinued in one female patient with resumption of her menstrual cycles. In this small population of patients treated with sirolimus, the prevalence rate of reversible gonadal dysfunction and infertility was significant in both males and females. Infertility secondary to sirolimus is under-diagnosed and should be studied further.     

Candida glabrata fungemia in transplant patients receiving voriconazole after fluconazole

The clinical impact of voriconazole resistance in Candida glabrata is not well described. Five hematopoietic stem cell transplant recipients that developed breakthrough Candida glabrata bloodstream infections while receiving voriconazole are described and the clinical management and susceptibility profiles of their isolates are reported. All patients were markedly immunosuppressed, and in all cases, voriconazole use was preceded by prolonged fluconazole exposure (median 60 days); median voriconazole exposure prior to candidemia was 48 days. Isolates from 4 patients were shown to be resistant to fluconazole and itraconazole when tested in vitro; these same isolates had MICs to voriconazole and posaconazole > or = 2 microg/ml. Clinical failure to voriconazole may result from deficits in host defense, retained infected foci, and adaptation of the organism to environmental pressures, the specific sequence and mechanisms of which warrant further study. Clinicians must maintain a high index of suspicion for these infections in highly susceptible hosts despite voriconazole therapy, particularly when voriconazole use is preceded by prolonged fluconazole exposure.     

Respiratory tract viral infections in bone marrow transplant patients

BACKGROUND: Community respiratory viruses such as respiratory syncytial virus (RSV), adenovirus, influenza A, influenza B, and the parainfluenza group are frequent causes of respiratory disease in bone marrow transplant (BMT) patients. MATERIAL AND METHODS: During the period from March 1993 to August 1999, 810 samples of respiratory secretions, nasopharyngeal aspirate (NPA) or bronchoalveolar lavage (BAL), from 722 patients with upper respiratory infections symptoms at the BMT unit of the Federal University in the state of Paraná, Brazil were evaluated for respiratory virus infection. RESULTS: One hundred thirty-six (17%) samples were reactive in 62 patients. RSV was found in 30 of 62 (48%), influenza A in 14 of 62 (23%), influenza B in 9 of 62 (15%), parainfluenza group in 7 of 62 (11%), and adenovirus in 2 of 62 (3%) infected patients. The most frequent clinical manifestations were cough and fever. Pneumonia occurred in 19 of 62 (31%) cases. The mortality rate was 23 of 62 (37%), being higher among patients infected with adenovirus and influenza A. CONCLUSIONS: Infections in BMT patients occurred during the outbreak period of these viruses in the community, highlighting the need to establish surveillance measures in units with immunocompromised patients in addition to the development of sensitive and rapid diagnostic tests for the detection of these viruses in patients with respiratory symptoms.     

Guillain-Barre syndrome in organ and bone marrow transplant patients

BACKGROUND: Guillain-Barre Syndrome (GBS) is believed to be caused by autoimmune mechanisms that are predominantly T-cell mediated. We report GBS in organ transplant patients and bone marrow transplant patients, both of whom have iatrogenically suppressed T-cell function. METHODS: We reviewed the Duke University Medical Center database from 1989-1999 for all patients who met the criteria for GBS. There were a total of 212 patients. Of these patients, two had undergone organ transplantation and two had undergone autologous bone marrow transplantation. RESULTS: Our report supports the notion that the humoral immune system is involved in the pathogenesis of GBS. Contrary to previous reports, however, functional recovery can occur without return of T-cell function. CONCLUSIONS: This suggests that in organ transplant patients, GBS may be humorally mediated and, even more importantly, responds well to treatment.     

Open lung biopsy in pediatric bone marrow transplant patients

Purpose: The aim of this study was to evaluate the clinical benefits of open lung biopsy in the diagnosis and treatment of pulmonary infiltrates in children who have undergone bone marrow transplantation. Methods: The authors retrospectively reviewed the medical records of all patients in whom pulmonary infiltrates developed within 6 months after bone marrow transplantation. Of 528 patients who received bone marrow transplants (313 allogeneic, 215 autologous) at St Jude Children's Research Hospital between June 1991 and December 1998, 83 (16%) had radiographic evidence of pulmonary infiltrates after the procedure. Of these, 43 (52%) underwent bronchoalveolar lavage (BAL), 19 (23%) underwent open lung biopsy (OLB), 6 (7%) underwent needle biopsy, and 5 (6%) underwent transbronchial biopsy; 21 received medical therapy alone. The authors evaluated the outcome, culture results, histopathologic findings, radiographic findings, and clinical features of those who underwent OLB. Results: The 19 patients ranged in age from 0.9 to 19.8 years (median, 11.4 years). Histopathologic studies indicated an infectious process in 6 patients (30%), bronchiolitis obliterans organizing pneumonia (BOOP) in 5 (26%), interstitial pneumonitis (IP) in 4 (21%), gangliosidosis in 1, and lymphocytic infiltrate in 1. Although the clinical plan was changed on the basis of the histopathologic diagnosis for 17 of the 19 patients (90%), improvement in outcome was seen in only 8 (47.5%) of these patients. Postoperative morbidity (30 days) was 47% and included prolonged intubation (7 patients), pneumothorax (2 patients), and pleural effusion (1 patient). The 30-day survival rate was 63.2% [plusmn] 10.6%. No patient with multisystem organ failure (MSOF), ventilator dependence, or a postoperative complication survived after OLB. Conclusions: Histopathologic analysis of OLB specimens is very accurate in determining the cause of pulmonary infiltrates in pediatric patients who have undergone BMT, but OLB may not improve patient outcome. Because the postoperative morbidity and mortality rates associated with OLB are high, careful patient selection is necessary. The mortality rates of patients with MSOF or ventilator dependence are particularly high; therefore, less-invasive alternatives for diagnosis of pulmonary lesions should be considered before OLB is performed.