Monitoring of Chimerism After Transplantation in Patients With β Thalassemia Major and the Treatment Strategies for the Reduction of Chimerism

Study Overview
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Brief Summary
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Hematopoietic stem cell transplantation is currently the only way to cure thalassemia, one of its main obstacles is the rejection after transplantation, chimerism continued to decline, which eventually lead to transplant failure. chimerism is a key indicator of the succession of immune response, which is a key indicator for predicting the failure of hematopoietic stem cell transplantation and provides an important basis for early detection of rejection. Transplantation of continuous chimerism can detect early unstable chimeras and rejection.The chimerism rates after transplantation were continuously monitored using fluorescence labeled multiplex PCR amplification of short tandem repeats (STR-PCR) ,and then follow our STR different rates for early interventional therapy to prevent further reduction in chimerism leading to lead to graft failure.

Official Title
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Monitoring of Chimerism After Transplantation in Patients With β Thalassemia Major and the Treatment Strategies for the Reduction of Chimerism

Conditions
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Beta Thalassemia Major

Intervention / Treatment
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* Drug: Interleukin-2
* Drug: Donor Regulatory T-Lymphocytes


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of thalassemia major There is no restriction on age or gender. Underwent allogeneic hematopoietic stem cell transplantation, including sibling transplantation, unrelated transplantation and haploidentical transplantation. On +45 day after transplantation, check patients with STR less than 80%. Patients underwent reduce of dosage with a failure treatment by Body condition score (ECOG score) is less than or equal to 1 point who meet follow-up conditions. Exclusion Criteria: Complicated with severe cardiac insufficiency and cardiac ejection fraction (EF) was lower than 50%. Complicated with severe pulmonary insufficiency (obstructive and / or restrictive ventilatory disorders). Complicated with severe liver function damage and liver function index (ALT or TBIL) is more than 2 times of the upper limit of the normal value. Complicated with severe renal dysfunction and renal function index (Cr or BUN) is 2 times of the upper limit of the normal value. Complicated with severe active bleeding
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: interleukin-2<br>interleukin-2 treatment per month | Drug: Interleukin-2<br>* On +60 day after transplantation,check patients with STR more than or equal to 90%. transplantat interleukin-2 treatment per month<br>|
| Active Comparator: DLI<br>donor lymphocyte infusion (DLI) treatment per month | Drug: Donor Regulatory T-Lymphocytes<br>* On +60 day after transplantation,check patients with STR less than 90%. Donor Regulatory T-Lymphocytes infusion (DLI) treatment per month<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Chimerism after transplantation were monitored using fluorescence labeled multiplex PCR amplification of short tandem repeats (STR-PCR) | β thalassemia major patients underwent reduced chimerism rate after allogeneic hematopoietic stem cell transplantation were collected and the chimerism rates after transplantation were continuously monitored using fluorescence labeled multiplex PCR amplification of short tandem repeats (STR-PCR).Monitoring once every 20-30 days after allogeneic hematopoietic stem cell transplantation.For patients with reduced chimerism, the results were grouped.We monitor STR-PCR once every 20-30 days after different treatment. | Change from chimerism rate at 2-3 months after different treatment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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donor ymphocytes, thalassemia, transplantation, chimerism