B-cell precursors differentiated from cord blood CD34+ cells are more immature than those derived from granulocyte colony-stimulating factor-mobilized peripheral blood CD34+ cells

Umbilical cord blood (CB) has been widely used instead of bone marrow (BM) and peripheral blood (PB) for stem cell transplantation (SCT). However, problems of sustained immunodeficiency after CB transplantation remain to be resolved. To elucidate the mechanism of immunodeficiency, we compared the characteristics of B cells differentiated in vitro from CD34+ cells of CB with those of PB. Purified CD34+ cells from CB and PB were cultured on murine stroma cell-line MS-5 with stem cell factor and granulocyte colony-stimulating factor for 6 weeks. The B-cell precursors (pre-B cells) that differentiated in this culture system, were analysed as to their immunoglobulin heavy chain (IgH) variable region gene repertoire and the expression of B-cell differentiation-related genes. CD10+ CD19+ pre-B cells were differentiated from both PB and CB. Although the usages of IgH gene segments in pre-B cells differentiated from CB and PB were similar, the N region was significantly shorter in CB-derived than PB-derived cells. Productive rearrangements were significantly fewer in cells of CB than PB in the third week. Among a number of B-cell differentiation-related genes, the terminal deoxynucleotidyl transferase (TdT) gene was not expressed in CB-derived cells during the culture. These results indicated that immature features of pre-B cells from CB, such as lack of TdT expression, and a short N region and few productive rearrangements in the IgH gene, might cause the delay in mature B-cell production.     

Surface phenotype analysis of CD16+ monocytes from leukapheresis collections for peripheral blood progenitors

In peripheral blood progenitor cell (PBPC) collections from patients with solid tumour or haematological malignancy, monocytes were separated into two subpopulations. The majority of monocytes expressed CD14 at a high density without CD16 antigen (the CD14+CD16- monocytes). The remaining monocytes co-expressed CD14 and CD16 (the CD14+CD16+ monocytes). These CD14+CD16+ monocytes amounted to 20.6 +/- 15.8%, while those in peripheral blood (PB) obtained from healthy volunteers were 7.3 +/- 3.1% (P < 0.05). When subdividing the CD14+CD16+ monocytes into CD14brightCD16dim and CD14dimCD16bright cells, both populations were found to be increased in PBPC collections. Since typical CD14+CD16+ monocytes are the CD14dimCD16bright population, we compared the additional surface antigens on CD14dimCD16bright monocytes with those of CD14+CD16- monocytes. In PBPC collections, the CD14dimCD16bright monocytes exhibited lower levels of CD11b, CD15, CD33 and CD38 expression and higher levels of CD4, CD11a, CD11c and MHC class II, and also revealed a higher percentage of CD4+ cells and a lower percentage of CD15+ cells and CD38+ cells, compared with the CD14+CD16- monocytes. When compared with the CD14dimCD16bright monocytes in PB, those in PBPC collections exhibited higher expression of CD4 and lower expression of CD11b, and also showed higher percentages of CD4+ cells and CD38+ cells and a lower percentage of CD11b+ cells. These results suggest that PBPC collections may be rich in the CD14+CD16+ monocytes in which the proportion of the immature population is increased. It is likely that these monocytes participate in the haematological and immune recovery after PBPC transplantation.     

Cord blood G(0) CD34+ cells have a thousand-fold higher capacity for generating progenitors in vitro than G(1) CD34+ cells.

We examined the functional differences between G(0) and G(1) cord blood CD34+ cells for up to 24 weeks in serum-free suspension culture, containing Flt-3 ligand, thrombopoietin and stem cell factor. By week 24, there is more than a 1,000-fold difference in granulocyte, macrophage-colony-forming cells (GM-CFC) cumulative production between the two populations, with cultures initiated from G(0) demonstrating an amplification of 1.1 x 10(5)-1.8 x 10(6) of GM-CFC compared to 45-2.7 x 10(3) for the G(1) cells. Cells from the initial G(0) population are able to produce about 250-fold higher numbers of BFU-E than those from G(1) which translates to 3 x 10(3)-1.1 x 10(5)-fold expansion and 25-390-fold expansion for G(0) and G(1), respectively. This amplification of the progenitor cells is reflected in finding that a greater proportion of the progeny of the G(0) population are CD34+, resulting in a 600-fold expansion of CD34+ cells at week 8. As in other in vitro systems, total cell expansion is less discriminatory of stem cell behavior than progenitor cells, and there is no significant difference in total cell numbers between G(0) and G(1) cultures with a mean fold expansion of 2 x 10(7) at 24 weeks.     

Inhibition of thymopoiesis of CD34+ cell maturation by HIV-1 in an in vitro CD34+ cell and thymic epithelial organ culture model

The mechanisms by which HIV-1 affects thymopoiesis were determined by preincubating CD34+ cells or cultured thymic epithelial (CTE) cells with lymphotropic (T-) and monotropic (M-) strains of HIV-1 in an in vitro CTE organ and CD34+ cell coculture model that allows for analysis of development of thymocytes and mature T cells. When purified CD34+ cells were precultured with either T- or M-tropic strains of HIV-1, thymopoiesis was impaired in a two-week coculture manifested by decreased cell number of thymocytes generated. However, the percentages of thymocyte subpopulations were comparable to control uninfected cocultures. Furthermore, HIV infection of thymocytes was predominantly observed in the CD44+CD3- population. However, in a four-week coculture experiment, HIV infection and depletion of more mature thymocytes were also observed. When CTE cells were preincubated with T- and M-tropic strains of HIV before addition of CD34+ cells, the number of thymocytes and subpopulations of thymocytes at early and later stages of maturation were markedly decreased. Furthermore, CD34+ and CD44+CD3- cells become HIV-infected. In summary, HIV-1 infection inhibited thymocyte maturation at early stages of thymocyte maturation CD44+CD25-CD3-. In addition, HIV also depleted later stages of CD4+ thymocyte subpopulations.     

Effect of tresperimus on in vitro human cord blood CD34+ cell differentiation

Tresperimus, an analogue of 15-deoxyspergualin (15-DSG), is immunosuppressive and prevents lethal graft-versus-host disease following allogeneic bone marrow transplantation in mice. Here, we present an in vitro dose response study examining the ability of tresperimus to support clonogenesis in cultured CD34+ cord blood stem cells. Our findings revealed that only the lowest dose examined, 0.5 microg tresperimus/ml, supports normal myelopoiesis, erythropoiesis and megakaryopoiesis. Greater concentrations of the drug induced dose-dependent inhibition of clonogenesis. This latter effect was not due to apoptosis and was reversible by drug withdrawal. We conclude that tresperimus at 0.5 microg/ml supports the clonogenic potential of cord blood CD34+ cells. Dose-dependent inhibition of clonogenesis was completely reversible following drug withdrawal. These results may be of clinical interest as tresperimus is currently used in phase I-III studies for the prevention of graft versus host disease in recipients of allogeneic bone marrow.     

Matched-pair analysis of hematopoietic progenitor cell mobilization using G-CSF vs. cyclophosphamide, etoposide, and G-CSF: enhanced CD34+ cell collections are not necessarily cost-effective.

Using matched-pair analysis, we compared two popular methods of stem cell mobilization in 24 advanced-stage breast cancer patients who underwent two consecutive mobilizing procedures as part of a tandem transplant protocol. For the first cycle, 10 microg/kg/day granulocyte colony-stimulating factor (G-CSF) was given and apheresis commenced on day 4 and continued for < or =5 days (median 3 days). One week after the first cycle of apheresis, 4000 mg/m2 cyclophosphamide, 400 mg/m2 etoposide, and 10 microg/kg G-CSF were administered for < or =16 days (cycle 2). Apheresis was initiated when the white blood cell (WBC) count exceeded 5000 cells/microL and continued for < or =5 days (median 3 days). Mean values of peripheral blood WBC (31,700+/-3200 vs. 30,700+/-3300/microL) were not significantly different between cycles 1 and 2. Mean number of mononuclear cells (MNC) collected per day was slightly greater with G-CSF mobilization than with the combination of chemotherapy and G-CSF (2.5+/-0.21x10(8) vs. 1.8+/-0.19x10(8) cells/kg). Mean daily CD34+ cell yield, however, was nearly six times higher (12.9+/-4.4 vs. 2.2+/-0.5x10(6)/kg; p = 0.01) with chemotherapy plus G-CSF. With G-CSF alone, 13% of aphereses reached the target dose of 5x10(6) CD34+ cells/kg in one collection vs. 57% with chemotherapy plus G-CSF. Transfusions of red blood cells or platelets were necessary in 18 of 24 patients in cycle 2. Three patients were hospitalized with fever for a median of 3 days after cycle 2. No patients received transfusions or required hospitalization during mobilization with G-CSF alone. Resource utilization (cost of drugs, aphereses, cryopreservation, transfusions, hospitalization) was calculated comparing the median number of collections to obtain a target CD34+ cell dose of 5x10(6) cells/kg: four using G-CSF vs. one using the combination in this data set. Resources for G-CSF mobilization cost $7326 vs. $8693 for the combination, even though more apheresis procedures were performed using G-CSF mobilization. The cost of chemotherapy administration, more doses of G-CSF, transfusions, and hospitalizations caused cyclophosphamide, etoposide, and G-CSF to be more expensive than G-CSF alone. A less toxic and less expensive treatment than cyclophosphamide, etoposide, and G-CSF is needed to be more cost-effective than G-CSF alone for peripheral blood progenitor cell mobilization.     

The intermediate filament protein synemin (SYNM) was found to be more widespread in CD117+ gastrointestinal stromal cell tumors (GIST) than the CD34 transmembrane phosphoglycoprotein: an immunohistochemical study

Interstitial cells of Cajal (ICC) are the pacemaker cells in the gastrointestinal system, initiating the rhythmic systematic contraction of smooth muscle to regulate peristalsis. Benign ICC are identified immunohistochemically by positive staining for CD117, c-kit tyrosine kinase receptor. CD117 expression is maintained during the malignant transformation of ICC into gastrointestinal stromal cell tumors (GIST). However, to date, no single reliable marker for GIST has been identified by immunohistochemical (IHC) staining, and correct diagnosis depends on IHC staining results using multiple markers. This study compared the reactivities of synemin (SYNM) intermediate filament protein and CD34, a known marker for stem cells, endothelial cells, and many GIST tumors, in 54 formalin-fixed, paraffin-embedded GIST, which were determined by this study to be CD117 positive. Double-immunofluorescence (IF) staining was also used to assess whether CD117 and SYNM were co-expressed by ICC. While 81.5% of the GIST were CD34⁺, 92.9% of these tumors were SYNM⁺. ICC were CD117⁺/SYNM⁺, whereas mast cells were CD117⁺/SYNM^?. Because the percentage of CD117⁺/SYNM⁺ GIST was higher than the percentage of 117⁺/CD34⁺ GIST, this study suggested that SYNM was a better marker than CD34 for GIST diagnosis. In addition, differential expression of SYNM and CD117 helped distinguish between ICC and mast cells.     

严重自身免疫性疾病患者的外周血CD34+细胞动员

目的探讨严重自身免疫性疾病患者外周血CD34 细胞动员的规律和安全性。方法以CTX rhG-CSF方案对严重自身免疫性疾病患者进行外周血CD34 细胞动员。结果动员后可获得单个核细胞(MNC)4.52(1.15~14.05)×108/kg,其中CD34 细胞为5.18(1.30~26.35)×106/kg。19例次患者注射CTX后ANC<0.5×109L-1,获得MNC 4.33(1.15~9.5)×108/kg、CD34 细胞5.16(1.30~26.35)×106/kg;23例次患者注射CTX后ANC≥0.5×109L-1,获得MNC 4.45(1.21~14.05)×108/kg、CD34 细胞5.41(1.0~24.10)×106/Kg。2组间无差异。动员过程中原发病无明显恶化,所有患者原发病均得到不同程度的缓解。其中SLE患者SLE-DAI评分由17(12~24)分降至3(0~4)分(P<0.01),RA患者均达到ACR20标准。1例患者出现急性肾功能衰竭,1例患者死于TTP,3例患者动员失败。结论以CTX rhG-CSF方案可有效地动员出足够的CD34 细胞,并能缓解原发病。动员过程中不良反应可耐受,但仍发生严重并发症甚至死亡。在少数动员失败的患者中,原因尚需进一步探讨。     

Drugs as a Frequent Cause of Acute Rash in Patients after CD34+-Selected Peripheral Blood Stem Cell Transplantation

Although histopathological differences have been reported between acute graft-versus-host disease (aGVHD) rash and non-aGVHD rash in CD34⁺-selected peripheral blood stem cell transplantation (PBSCT) recipients, skin biopsy alone is usually insufficient to determine rash etiology. As such, distinguishing inflammatory non-aGVHD rashes, such as drug eruptions, from cutaneous aGVHD after CD34⁺-selected PBSCT remains challenging and relies on clinical presentation. This study aimed to identify etiologies of skin rash in the first year after CD34⁺-selected PBSCT and to assess whether laboratory serologic markers, transplant characteristics, and rash morphology and symptomatology aid in differentiation of cutaneous aGVHD rash versus non-aGVHD rash. We conducted a retrospective study of 243 adult patients who underwent CD34⁺-selected PBSCT at Memorial Sloan Kettering Cancer Center between 2008 and 2011. Among this cohort of transplant recipients, only 43 patients (17.7%) developed cutaneous aGVHD. A total of 152 patients (63%) were identified with rash within 1 year after PBSCT. The proportion of patients who experienced peripheral eosinophilia was not different between those with an aGVHD versus non-aGVHD rash (P ≥ .90), nor when stratified by CD34⁺ selection method (Isolex, P = .70; CliniMACS, P≥ .90). The proportion of patients with pruritus was also not different between those with an aGVHD rash versus non-aGVHD rash (P= .20), or when stratified by CD34⁺ selection modality (Isolex, P = .20; CliniMACS, P = .50). The most common cause of non-aGVHD rash among those with a clear etiology was drug (39% of Isolex; 26% of CliniMACS). Single drug culprits were identified in 51% of drug rashes. The most commonly reported offending agents included antibiotics, keratinocyte growth factor, chemotherapy, and recombinant glycosylated human IL-7.     

转基因饲养层细胞体外促进脐带血CD34+HSPC增殖

hOSM基因饲养层细胞可以有效地扩增CD34+HSPC,并维持其较高的移植效率和造血活性.     

Impact of a Low CD34+ Cell Dose on Allogeneic Peripheral Blood Stem Cell Transplantation

Although the CD34⁺ cell dose in allogeneic peripheral blood stem cell transplantation (PBSCT) is considered to be associated with transplantation outcomes, a lower acceptable threshold has not been defined. We retrospectively analyzed 2919 adult patients with hematologic malignancies who underwent related PBSCT in Japan between 2001 and 2014. According to the number of CD34⁺ cells in the graft, we categorized 2494 patients in the standard group (2 to 5 × 10⁶ cells/kg), 377 patient in the low group (1 to 2?×?10⁶ cells/kg), and 48 patients in the very low group (<1?×?10⁶ cells/kg). Compared with the standard group, the low and very low groups showed delayed neutrophil recovery (93.8%, 89.5%, and 78.3%, respectively at day +28; P?<?.001) and platelet recovery (69.3%, 53.0%, and 45.5%, respectively at day +28; P?<?.001). The 2-year overall survival (OS) in the 3 groups was 45.5%, 45.3%, and 29.8%, respectively, with inferior survival in the very low group. However, a higher percentage of high-risk patients may account for the inferior survival in the very low group, and no significant difference in OS was found in a multivariate analysis. There were no differences in relapse, nonrelapse mortality, or the development of graft-versus-host disease among the 3 groups. In conclusion, allogeneic PBSCT with low CD34⁺ cell doses of 1 to 2?×?10⁶ cells/kg gives acceptable results, whereas further investigations are needed to evaluate the effects of lower doses of <1?×?10⁶ cells/kg owing to the smaller number and the higher percentage of patients with adverse prognostic factors in this cohort.     

Functional characterization of TPO-expanded CD34+ cord blood cells identifies CD34- CD61- cells as platelet-producing cells early after transplantation in NOD/SCID mice and rCD34+ cells as CAFC colony-forming cells

Transplantation of thrombopoietin (TPO)-expanded cord blood CD34(+) cells accelerates human platelet recovery in NOD/SCID mice. It is unknown which subpopulations of the TPO-expanded cells mediate accelerated platelet recovery and bone marrow (BM) engraftment. In this study, the contribution of these subpopulations to human platelet appearance in the blood and BM engraftment was studied in NOD/SCID mice. Following transplantation of CD34(-) /CD61(-)/lineage(-) cells (Lin(-)), human platelets were detected in the blood of recipient mice from day 4. Both time to platelet recovery and blood platelet counts at 6 weeks after transplantation showed Lin(-) dose dependence. The Lin(-) population was virtually negative for lineage marker expression and lacked CD42b expression but was heterogeneous with regard to CD36 and CD38 expression, reflecting a population in transit but not fully committed toward the megakaryocyte (MK) lineage. Although no definitive phenotype could be established of the cells generating prompt platelet production and cells generating platelets 6 weeks after transplantation, this relatively heterogeneous Lin(-) population is prerequisite to accelerate platelet recovery in vivo. The interval to platelet recovery after transplantation of the CD34(+) cells remaining after expansion (rCD34(+)) was similar to mice transplanted with nonexpanded CD34(+) cells, although the total platelet counts and the engraftment levels in the BM were lower. Cobblestone area-forming cell colony-forming cells resided mostly in the rCD34(+) population. The pro-MK CD61(+) cells did not contribute to human platelet recovery or engraftment in the BM. Our study shows that not all expanded cells appear critical for transplantation. These data support that functional characterization of the expanded cell populations is warranted to make future expansion protocols suitable for clinical application.     

CD105 is a more appropriate marker for evaluating angiogenesis in urothelial cancer of the upper urinary tract than CD31 or CD34

Angiogenesis plays an important role in cancer progression in many types of cancer. Evaluation of angiogenesis is often performed, but the optimal methodology for human cancer has not been agreed upon. As adequate evaluation of angiogenesis in cancer tissues might be important for prediction of prognosis and treatment decisions, we evaluated angiogenesis semiquantitatively by assessing microvessel density (MVD) in urothelial cancer of the upper urinary tract (UC-UUT). We compared the performance of three endothelial cell markers (CD31, CD34, and CD105) on formalin-fixed tissues from 122 patients diagnosed with UC-UUT without metastasis. Vascular endothelial growth factor (VEGF)-A expression was also evaluated immunohistochemically. Correlations between MVD with each marker and pT stage, grade, survival, and VEGF-A expression were investigated. Mean (standard deviation) MVD as estimated by immunohistochemical staining with anti-CD31, anti-CD34, and anti-CD105 were 47.1 (17.9)/high-power field (HPF), 70.9 (19.5)/HPF, and 31.2 (16.7)/HPF, respectively. Although all MVDs were significantly associated with pT stage and grade, CD105-MVD showed the strongest association. Similarly, CD105-MVD showed the strongest correlation with VEGF-A expression (r?=?0.530, p?<?0.001). Although all MVDs were associated with metastasis-free survival and cause-specific survival on univariate analysis, only CD105-MVD was retained as an independent predictor in multivariate analysis including pT stage and grade. CD105-MVD may be the preferred marker for semiquantitative assessment of angiogenesis in patients with UC-UUT.     

Microvessel density as a predictor of PSA recurrence after radical prostatectomy. A comparison of CD34 and CD31

Whether prostate cancer recurrence can be predicted by microvessel density (MVD) measurements is controversial. One reason for the lack of agreement may be the differing antibodies used to determine MVD. We evaluated MVD using 2 different antibodies against endothelial cells, CD31 and CD34, on 102 patients who underwent radical prostatectomy without adjuvant hormonal therapy. The tumors from these cases were identified, and areas with the highest Gleason pattern were immunostained. Average MVD determined by CD31 (MVD/CD31) staining was significantly lower than that obtained by MVD/CD34 staining (60.1 vs 80.3). By using Kaplan-Meier analysis, prostate-specific antigen (PSA) recurrence was correlated with MVD/CD31 and MVD/CD34. MVD/CD34 and MVD/CD31 were associated strongly with PSA recurrence on a univariate level. However, only MVD/CD34 was an independent predictor of PSA failure. Therefore, some of the confusion about MVD value as a prognostic indicator may be due to the antibodies used.     

Hematopoietic engraftment in recipients of unrelated donor umbilical cord blood is affected by the CD34+ and CD8+ cell doses.

Umbilical cord blood (UCB) transplantation is limited by the low number of hematopoietic stem cells in UCB units, which results in a low engraftment rate in transplant recipients. Here, we measured the total nucleated cell count and CD34(+), CD3(+), CD4(+), CD8(+), CD14(+), and CD16(+)/56(+) cell doses in each UCB unit and evaluated their influence on engraftment and other outcomes in 146 recipients. Multivariate analysis showed a significant association between a higher incidence of successful engraftment and a dose of CD34(+) and CD8(+) cells above the median (1.4 x 10(5) and 15.7 x 10(5) cells/kg, respectively). Engraftment occurred 4 days earlier in patients who received UCB with more than the median dose of CD34(+) cells than those receiving UCB at or below the median. Stratification of the group according to CD34(+) cell dose revealed a significant influence of the CD8(+) cell dose on the time to achieve neutrophil engraftment in patients receiving a lower CD34(+) cell dose, whereas there was no significant influence in the patients receiving a higher CD34(+) cell dose. These results suggest that consideration of CD34(+) and CD8(+) cell doses in UCB units may improve the engraftment in recipients of UCB transplantation.