Characterization of Clonogenic Progenitors in Autologous Peripheral Blood Stem Cell Grafts: Evaluation of a Simple In Vitro Assay Suitable for Routine Clinical Use

Little is known about the molecular characteristics of alloantigens recognized by alloreactive T cells mediating hematologic stem cell graft rejection. In particular, it has never been shown that such alloantigens can be encoded by HLA-DPβ alleles. Indeed, matching for HLA-DP antigens is generally not considered to be of functional importance for the outcome of allogeneic bone marrow or peripheral blood stem cell transplantation. In this study, a case of peripheral blood stem cell allograft rejection was investigated in which the patient and donor differed for a single mismatch at HLA-DP in the rejection direction. Patient-derived T lymphocytes circulating at the time of rejection showed direct ex vivo cytotoxic activity against donor-derived B-lymphoblastoid cells as well as other HLA-DPβ1*0901–expressing targets. The presence of HLA-DPβ1*0901–specific effectors in vivo was further confirmed by in vitro stimulation experiments. CD4+ T-cell lines and clones with specific cytotoxic activity against HLA-DPβ1*0901–expressing targets including donor B-lymphoblastoid cells were generated both by nonspecific and by donor-specific in vitro stimulation. Taken together, these data demonstrate that HLA-DP can be the target antigen of cytotoxic CD4+ T lymphocytes involved in peripheral blood stem cell allograft rejection.

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In Vitro Evaluation of the Procoagulant Properties of Autologous Peripheral Blood Stem Cell Transplant

Blood ◽

10.1182/blood.v120.21.1134.1134 ◽

2012 ◽

Vol 120 (21) ◽

pp. 1134-1134

Author(s):

Fatoumata Sidibe ◽

Vassiliki Galea ◽

Francoise Robert ◽

Marie-Paule Romain ◽

Jérome Larghero ◽

...

Keyword(s):

Stem Cell ◽

Peripheral Blood ◽

Thrombin Generation ◽

Stem Cell Transplant ◽

Peripheral Blood Stem Cell ◽

Autologous Transplantation ◽

Blood Stem Cell ◽

Control Group ◽

Cell Transplant

Abstract Abstract 1134 Background: Autologous transplantation is a treatment option for bone marrow toxicity induced by chemotherapy and/or radiotherapy in cancer patients. Although it improves patient survival, autologous transplantation is associated with thrombotic complications. The procoagulant properties of autologous peripheral blood stem cell transplant (APBSCT) have never been characterized. The aim of this study was to determine in vitro the procoagulant properties of APBSCT transfused in patients with solid tumors. Methods: Samples of APBSCT from 10 consecutive patients eligible for autologous transplantation were studied. The ability of APBSCT to induce in vitro thrombin generation in normal platelet poor or rich plasma (PPP or PRP respectively) was evaluated. The APBSCT was diluted 1/10 in PPP or PRP. Thrombin generation was measured using the Calibrated Automated Thrombogram (Thrombinoscope bv Stago France). In control experiments the APBSCT was replaced by saline. Platelet- and erythrocyte-derived microparticles (PdMP and EdMP respectively) were determined by flow cytometry using monoclonal antibodies anti-CD41-PE and anti-CD235a-PE respectively. Five out of 10 samples of APBSCT were also studied for tissue factor (TF) and phosphatidylserine (PS) expression. The TF was revealed by the monoclonal antibody anti-CD142-PE and PS by annexin V-FITC. Results: In both PPP and PRP experiments, APBSCT increased thrombin generation compared with the controls. In the presence of the APBSCT, the chronometric parameters of the thrombogram (lag time and time-to-peak) were significantly shorter and the peak and mean rate index (MRI) were significantly increased as compared to the experiment controls. The endogenous thrombin potential (ETP) was the only parameter of the thrombogram that was not influenced (Table). Increased expression of PdMP was noticed in APBSCT samples as compared to the control group (23979 ± 29 204 versus 752 ± 432, p <0.001). No significant difference was found in EdMP (55 ± 67 versus 69 ± 49, p> 0.05). In the five samples PS had a greater mean fluorescence intensity as compared to the control group (PS = 25 ± 6 versus 9 ± 4, p <0.01). In contrast, TF was not significantly different (FT = 5 ± 4 versus 4 ± 2, p> 0.05). Conclusion: The APBSCT used for autologous transplatation in patients with solid cancer accelerate in vitro thrombin generation in PPP and PRP and presents significant procoagulant properties. These procoagulant properties of APBSC are related to an important expression of PdMP and PS. Whether the transfusion of the APBSCT induces a hypercoagulable state in vivo that merits further investigation. Table: Parameters of thrombogram. * p<0.05, ** p<0.01 APBSCT induced thrombin generation was compared to saline experiments. APBSCT: autologous peripheral blood stem cell transplant, PPP: Plasma poor in platelets, PRP: plasma rich in platelets, ETP: endogenous thrombin potential, MRI: mean rate index. Disclosures: No relevant conflicts of interest to declare.

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High-activity samarium-153-EDTMP therapy followed by autologous peripheral blood stem cell support in unresectable osteosarcoma

Nuklearmedizin ◽

10.1055/s-0038-1625284 ◽

2001 ◽

Vol 40 (06) ◽

pp. 215-220 ◽

Cited By ~ 33

Author(s):

S. Bielack ◽

S. Flege ◽

J. Eckardt ◽

J. Sciuk ◽

H. Jürgens ◽

...

Keyword(s):

Stem Cells ◽

Stem Cell ◽

High Activity ◽

Peripheral Blood ◽

Peripheral Blood Stem Cell ◽

Blood Stem Cell ◽

High Dose ◽

External Radiotherapy ◽

Primary Tumor Site ◽

Hematopoietic Stem

Summary Purpose: Despite highly efficacious chemotherapy, patients with osteosarcomas still have a poor prognosis if adequate surgical control cannot be obtained. These patients may benefit from therapy with radiolabeled phosphonates. Patients and Methods: Six patients (three male, three female; seven to 41 years) with unresectable primary osteosarcoma (n = 3) or unresectable recurrent sites of osteosarcomas (n = 3) were treated with high-activity of Sm-153-EDTMP (150 MBq/kg BW). In all patients autologous peripheral blood stem cells had been collected before Sm-153-EDTMP therapy. Results: No immediate adverse reactions were observed in the patients. In one patient bone pain increased during the first 48 hrs after therapy. Three patients received pain relief. Autologous peripheral blood stem cell reinfusion was performed on day +12 to +27 in all patients to overcome potentially irreversible damage to the hematopoietic stem cells. In three patient external radiotherapy of the primary tumor site was performed after Sm-153-EDTMP therapy and in two of them polychemotherapy was continued. Thirty-six months later one of these patients is still free of progression. Two further patients are still alive. However, they have developed new metastases. The three patients who had no accompanying external radiotherapy, all died of disease progression five to 20 months after therapy. Conclusion: These preliminary results show that high-dose Sm-153-EDTMP therapy is feasible and warrants further evaluation of efficacy. The combination with external radiation and polychemotherapy seems to be most promising. Although osteosarcoma is believed to be relatively radioresistant, the total focal dose achieved may delay local progression or even achieve permanent local tumor control in patients with surgically inaccessible primary or relapsing tumors.

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