Combined analysis of Regulatory T- cell and ZAP-70 expression in patients with B-chronic lmphocytic leukemia
Wafaa Ahmed EL- neanaey1 and Dalia Ahmed Nafea2
1 Clinical Pathology Department, Faculty of Medicine, Alexandria University, Egypt.
2 Internal Medicine Department, Faculty of Medicine, Alexandria University, Egypt.
Abstract: Background: Evidence is accumulating on the role of T- cells in the pathogenesis and development of chronic lymphocytic leukemia .Attention has been recently focused on regulatory T-cells (T-reg), which are considered to play a key role in the regulation of immune responses to cancer. This study aimed to define the role of regulatory T- cells and ZAP-70 expression in disease progression and to evaluate their expression in response to therapy of CLL patients. Methods: 58 CLL patients (37 untreated and 21 CLL patients that were assessed before and after 4 cycles of treatment with fludarabine and cyclophosphamide) and 28 age and sex matched healthy controls were enrolled in this study. T-reg cells (CD4+CD25+) and ZAP-70expression were detected by flowcytometer .Results: T-reg % was significantly lower in CLL patients than controls (p=0.001) while absolute T reg count was significantly higher in CLL patients than controls (p=0.001). After treatment, absolute T-reg count was significantly decreased (p=0.001) and non-significant decrease was found in T-reg %( p= 0.582). For disease progression, absolute T-reg count was significantly increased in patients with Rai stages III-IV than the patients with Rai stages 0-II (p= <0.001).while no significant difference was found with T-reg % (p =0.697). In addition, there was an association between ZAP and staging of CLL (p=0.045). However, there was no significant difference in T-reg% and absolute T-reg count for ZAP -70 positive and ZAP-70 negative CLL patients. Conclusion: absolute T- reg count rather than T-reg % can be used as predictive marker for disease progression in CLL patients. The mechanism of T-reg expansion as well as the interaction between CLL cells and T-reg needs further studies before developing innovative immune approaches targeting T-reg cells in CLL.
[WafaaAhmed EL- neanaey and Dalia Ahmed Nafea. Combined analysis of Regulatory T- cell and ZAP-70 expression in patients with B-chronic lmphocytic leukemia. Life Sci J 2013;10(1):3323-3328]. (ISSN: 1097-8135).http://www.lifesciencesite.com.
Key words: B-CLL, T-Reg, flowcytometry.