Assessment of the use of immunosuppressants combined with cord blood for severe aplastic anemia.

BACKGROUND: The objective of this study was two-fold: 1) to investigate the changes of cytokines concentration in relation to severe aplastic anemia (SAA) when treated with immunosuppressants combined with cord blood (IS + CBI). and 2) to assess the curative effect of umbilical cord blood chimerism engraftment. METHODS: We selected 43 patients with SAA all treated with IS + CBI (newly diagnosed group). Among them, a total of 33 patients were treated effectively (effective group) while 10 cases were treated invalidly (invalid group). An additional 20 healthy individuals were selected as control (control group). The expression levels of IL-17, IL-22 and other cytokines in each group were detected by ELISA. The engraftment of cord blood stem cells was detected by using short tandem repeat-polymerase chain reaction (STR-PCR). RESULTS: 1. IL-17, IL-22 and other cytokines expressions in the newly diagnosed group were significantly higher than in the control group. 2. After six months, the levels in the effective group were significantly lower than pre-therapy levels (P < 0.05). The levels in the invalid group did not differ to those observed prior treatment. 3. After one and three months of treatment, a small amount of engraftment was found in the effective group. However, after six months, transplant rejection was observed in all patients. No effective engraftment was observed in the invalid group. CONCLUSION: 1) Th17 and Th22 producing cells in SAA patients significantly increased indicating a positive correlation between these biomarkers and the progression of SAA. 2) During the IS + CBI treatment the maintenance of a normal hematopoietic function depended on immunesup-pressants. Early umbilical cord blood chimerism engraftment may promote hematopoietic recovery.

Mechanism of immunosuppressants combined with cord blood for severe aplastic anemia.

This study aims to explore the mechanism of immunosuppressants combined with cord blood (IS + CBI) for severe aplastic anemia. Selecting 30 patients with SAA and all treated with IS + CBI (newly diagnosed group). 23 patients who were treated effectively (effective group) while 7 cases were treated invalidly (invalid group). Another 20 healthy individuals were selected as control group. To detect the expression levels of IL-17, IL-22 and other cytokines by ELISA method in each group. To detect the engraftment of cord blood stem cells by using short tandem repeat-polymerase chain reaction (STR-PCR) method. 1. IL-17, IL-22 and other cytokines expressions in newly diagnosed group were significantly higher than in the control group. 2. After 6 months, the level in effective group was significantly lower than pretherapy (P < 0.05).The level in invalid group had no obvious difference than pretherapy. 3. After 1 month and 3 months of treatment, a small amount of engraftment was found in effective group. After 6 months, implant rejection was showed. No effective engraftment was observed in invalid group. 1. IL-17, IL-22 cells in SAA patients increased which might positively correlated with the progression of SAA. 2. During the treatment of IS + CBI, there is a bridging mechanism between the early stage of engraftment and the advanced stage of immunosuppressant adjustment. The first 3 months after treatment, it relies on the engraftment of cord blood stem cells to promote hematopoietic recovery and 3 months later, it relies on immunosuppressants to maintain normal hematopoietic function.

[Clinical implications of combined measurement bone marrow T cells intracellular IFNgamma and HLA-DRB1*1501 measurement in predicting the response to immunosuppressive therapy for aplastic anemia].

OBJECTIVE: To evaluate the clinical implication of combined measurement of bone marrow (BM) T lymphocyte intracellular IFNgamma with HLA-DRB1*1501 in predicting the response to immunosuppressive therapy (IST) in patients with aplastic anemia (AA). METHODS: Enrolled into the present study were 51 idiopathic AA patients treated with cyclosporine A (CsA) based IST. BM CD(8)(+) T lymphocyte intracellular IFNgamma was determined with flow cytometry and HLA-DRB1*1501 detected with PCR-sequence specific primer before treatment. The relationship between laboratory indices and clinical response were investigated and the potential usefulness of parameters in predicting the response to IST for AA was evaluated. RESULTS: These HLA-DRB1*1501 shows sensitivity of 45.7% (16/35) and specificity of 87.5% (14/16) respectively. Intracellular IFNgamma has sensitivity of 94.3% (33/35) and specificity of 62.5% (10/16), respectively. With combination of intracellular IFNgamma with HLA-DRB1*1501, the parallel test increases the sensitivity of 97.1% (34/35) and the negative predictive value of 90.0% (9/10). On the other hand, the serial test improves the specificity and positive predictive value which both achieve 93.7% (15/16). It could be calculated through a logistic regression equation that the probabilities of prediction of four subgroups of patients whose results are both positive reaction, a positive intracellular IFNgamma plus negative HLA-DRB1*1501, a negative intracellular IFNgamma plus positive HLA-DRB1*1501 and both negative reaction are 89.0%, 77.4%, 34.5% and 18.2%, respectively. CONCLUSIONS: Combination of BM T cells intracellular IFNgamma stain and HLA-DRB1*1501 phenotype can be a useful predictor for AA patients in immunosuppressive therapy. The patients with both positive results of the two tests may have more possibilities to response to IST. It may have an important implication for the majority of AA patients whose intracellular IFNgamma stain has a positive reaction.

[Preliminary study of multivariable model in predicting response to immunosuppressive therapy in patients with aplastic anemia].

OBJECTIVE: To evaluate the potential usefulness of a multivariable model in predicting the response to immunosuppressive therapy (IST) in patients with aplastic anemia (AA), and its application to the clinical practice. METHODS: PB T cells subpopulation and BM T cells intracellular IFN-gamma and IL-4 were serially analyzed by flow cytometry (FCM) before and during treatment. HLA-DRB1 * 1501 phenotype was analyzed by PCR-SSP. The predictive potentials of different parameter combinations for clinical responsiveness were statistically assessed. RESULTS: In all evaluated parameters, CD8+ cell intracellular IFN-gamma had the relatively best diagnostic value with sensitivity and specificity of 94.3% and 62.5%, and positive and negative predictive value of 84.6% and 83.3% respectively. Positive CD8+ cell intracellular IFN-gamma plus Tc1/Tc2 < 50 could increase the positive predictive value to 92.3%. A multivariable model consisting of absolute neutrophil count (ANC), BM T cell intracellular IFN-gamma, Tc1/Tc2 ratio and HLA-DRB * 1501 phenotype of the patients was finally established. CONCLUSION: The multivariable model is superior to each of the single parameters in terms of predictive power of IST therapeutic outcome, and its higher accuracy and the clinical application make it potentially useful in practice.