الفهرس 
TitleOnly 14 pages are availabe for public view
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Abstract
Chronic lymphocytic leukemia is the most common leukemia in the western world. It is characterized by the accumulation in the blood, marrow and lymphoid tissues of mature monoclonal B lymphocytes that express the CD5 surface molecule. The leukemic CLL cell accumulation appears to be a result of defective apoptosis rather than uncontrolled proliferation. CLL patients develop immune deficiencies characterized by hypogammaglobulinemia and autoimmune diseases, suggesting immune dysregulation.
CLL is a disease that shows varying clinical progression. The Rai and Binet staging systems are useful to predict treatment requirements and survival, but fail to distinguish patients who may develop aggressive disease. The somatic mutations in the immunoglobulin heavy chain variable (IGVH) region are very valuable prognostic factors. IGVH-mutated patients have a better clinical outcome while nonmutated patients have a poorer prognosis.
ZAP70 has been described as a very valuable prognostic factor and surrogate marker of IgVH mutational status. Patients with ZAP70 positivity are characterized by worse clinical course and significantly shorter progression-free and overall survival.
However, both tests are costly, relatively laborious and not available in all hematology departments. Therefore, finding new prognostic markers for CLL has always been and still is a challenge for investigators.
The aim of the present work was to study the expression of CD1d as well as interleukin 22 level in patients with chronic lymphocytic leukemia in relation to disease characteristics.
This study included 40 chronic lymphocytic leukemia patients diagnosed in the MRI Hematology Department during the period from May 2015 to April 2017.In addition to 10 age and sex matched normal subjects as controls. All patients were subjected to the following:
1- Full history taking.
2- Thorough clinical examination.
3- Diagnostic hematological investigations:
• Complete blood count (CBC), Reticulocyte count and Coomb’s test.
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• Bone marrow examination if needed.
• Immunophenotyping for CLL panel to confirm diagnosis.
4- Chemical investigations:
• Lactate dehydrogenase enzyme (LDH).
• Beta-2-microglobulin.
• C-reactive protein level.
• Liver function tests.
• Kidney function tests.
5- Radiological investigations:
• Plain chest X-rays.
• Abdomino-pelvic ultrasound.
6- Estimation of ZAP-70 by flowcytometry.
7- CD1d expression by flowcytometry.
8- Estimation of interleukin 22 level by ELISA.
This study included 40 CLL patients, 22 males (55.0%) and 18 females (45.0%), with a male to female ratio of 1.3 : 1. Their age ranged from 44 years to 81 years with a mean of 63.55 ± 9.8 years.
Physical examination showed 82.5 % of them with lymphadenopathy, 85.0 % with splenomegaly and 32.5 % with hepatomegaly. Expression of ZAP-70 was negative in 35.0 % and positive in 65.0 % of them.
ZAP-70 expression showed significant statistical association with Rai staging (p=0.002) but not with Binet staging (p=0.235). Positive ZAP-70 expression was associated with significant statistical association with β2M .Serum LDH and CRP were also higher in positive ZAP-70 expressing patients, but the values were not statistically significant.
The mean expression of CD1d% was significantly lower among CLL patients in comparison to the control group (12.14 vs. 26.60 %). As well as, CD1d MFIr showed significantly lower mean value among CLL patients in comparison to the control (0.64 vs. 1.00).
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However, serum concentration of IL-22 showed significantly higher mean value among CLL patients compared to the control group (47.01 vs.10.64 pg/ml).
CLL patients were categorized as previously diagnosed (n=22) (55.0%) and newly diagnosed (n=18) (45.0%). There was no significant difference between the previously diagnosed vs. newly diagnosed CLL patients regarding CD1d %, MFIr or IL-22 pg/ml (p>0.05).
There was no significant difference between CD1d %, MFIr or IL-22 pg/ml and some clinical findings as lymphadenopathy, splenomegaly and hepatomegaly (p>0.05).
The mean expression of CD1d%, MFIr and IL-22 showed statistically significant difference in relation to Rai & Binet staging of CLL Patients (p<0.05).
Significantly higher mean values were observed among positive ZAP-70 expressing patients compared to negative ZAP-70 expressing patients regarding the CD1d % (18.15 vs. 0.96 %), MFIr (0.78 vs. 0.36) and IL-22 (51.94vs. 37.83 pg/ml) respectively.
The ROC curve showed that CD1d%, MFIr and IL-22 could be used as a sensitive indicator for positive ZAP-70 state, where the area under the curve was statistically highly significant (AUC= 0.780, p=0.004), (AUC= 0.798, p=0.002) & (AUC= 0.809, p=0.001) respectively.
Expression of CD1d% showed statistically significant positive correlation to β2-M, LDH, CRP, AST, ZAP-70, CD1d MFIr & IL-22 and significant negative correlation to hemoglobin concentration.
CD1d MFIr showed statistically significant positive correlation to β2-M, LDH, ZAP-70 & IL-22 and significant negative correlation to hemoglobin concentration.
Serum IL-22 level showed statistically significant positive correlation to β2-M, LDH, CRP & ZAP-70.
The present study found that CD1d expression can be easily determined by flowcytometry; thus, it can be readily and inexpensively used in conjunction with other prognostic markers or as a reliable sole marker at any time in the disease course. Also, (as observed by other authors) it can be used as a diagnostic marker since it can differentiate between CLL and other B-CLPDs.
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Moreover, the present work found that there were increased levels of serum IL-22 in CLL patients. Higher levels of serum IL-22 showed high predictive value for ZAP-70 positivity among CLL patients which put it as alternative marker for ZAP-70 expression since its measurement by ELISA is easier.
In addition, in the future, CD1d and IL-22 may be used as novel goals for CLL immunotherapy approaches.