American Journal of Biochemistry and Molecular Biology2150-42102150-4253Academic Journals Inc.10.3923/ajbmb.2018.23.33SabrySabry A. F. El-Senduny,Fardous K. AbousamraNashwa Salah EL-DinManal YoussefMagdy M. 1201881Background and Objectives: Chronic lymphocytic leukemia (CLL) is a cancer of B cell lymphocytes, originating in the bone marrow and affecting most body tissues. The objective of this study was to estimate the level of T helper 9 (Th9) cells and interleukin-9(IL-9) in CLL patients and the determination of their association with different clinical and prognostic parameters of CLL and correlation with clinical and laboratory measurements in CLL patients. Materials and Methods: This study included 70 Egyptian patients with CLL in addition to 15 healthy controls. The number of Th9 cells was determined by flow cytometry, serum concentration of IL-9 determined by enzyme-linked immunosorbent assay (ELISA) technique and IL-9 mRNA expression evaluated by qRT-PCR. Results: IL-9 level was significantly higher in CLL patients when compared to normal subjects. Higher levels of both Th9 cells and IL-9 in CLL patients were associated with fever, skin involvement, lymphadenopathy, chemotherapy treatment, lymphocyte doubling time (LDT) less than 1 year, TP53 Del (17p) and higher Rai stages. Serum IL-9 level, unlike circulating Th9 cells, was higher significantly in CLL patients positive for BCL2. Positive cases for CD38 and ZAP70 were strongly associated with higher levels of both Th9 cells and IL-9 levels. Conclusion: The current study indicated that Th9 cells and IL-9 contribute to the pathogenesis of CLL and are correlated with TP53 Del (17p), BCL2 expression and the more complex form of disease and worse prognosis. These results may allow one to speculate a potential therapeutic target of Th9 cells and IL-9 in CLL.]]>Byrd, J.C., J.J. Jones, J.A. Woyach, A.J. Johnson and J.M. Flynn,20143230393047Siegel, R.L., K.D. Miller and A. Jemal,201868730Neal, C., D. McGoldrick and R. Schear,20152015pp: 41-53pp: 41-53Miller, K.D., R.L. Siegel, C.C. Lin, A.B. Mariotto and J.L. Kramer et al.,201666271289Chiorazzi, N., K.R. Rai and M. Ferrarini,2005352804815Veldhoen, M., C. Uyttenhove, J. van Snick, H. Helmby and A. Westendorf et al.,2008913411346Kaplan, M.H., M.M. Hufford and M.R. Olson,2015in vivo function of T helper 9 cells.]]>15295307Buttrick, T.S., W. Wang, C. Yung, K.G. Trieu and K. Patel et al.,20182018Ciccia, F., G. Guggino, A. Rizzo, A. Manzo and B. Vitolo et al.,20155422642272Anuradha, R., P.J. George, L.E. Hanna, V. Chandrasekaran, P. Kumaran, T.B. Nutman and S. Babu,201319124662473Purwar, R., C. Schlapbach, S. Xiao, H.S. Kang and W. Elyaman et al.,20121812481253Liu, Z., H. Fan and S. Jiang,2013+ T‐cell subsets in transplantation.]]>252183191Koch, S., N. Sopel and S. Finotto,2017395568Noelle, R.J. and E.C. Nowak,201010683687Knoops, L. and J.C. Renauld,200422207215Lv, X., L. Feng, X. Fang, Y. Jiang and X. Wang,20136911916Gu, Z.W., Y.X. Wang and Z.W. Cao,20152015Al-Sawaf, O., A. Bazeos, S. Robrecht, J. Bahlo and A.M. Fink et al.,20172017Chen, N., K. Lu, P. Li, X. Lv and X. Wang,2014723192323Abbassy, H.A., R.A. Aboelwafa and O.M. Ghallab,201733477482Matutes, E. and A. Polliack,200042247Bauer, J.H., K.D. Liu, Y. You, S.Y. Lai and M.A. Goldsmith,199827392559260Yu, X., Y. Zheng, Y. Deng, J. Li and R. Guo et al.,20162016