Veterinary World

     Open access and peer reviewed journal  

ISSN (Online): 2231-0916


Home l Editorial board l Instructions for authors l Reviewer guideline l Open access policy l Archives l FAQ

Open Access

Research (Published online: 13-02-2016)

9. Expression of biologically active bovine interleukin 7 and evaluating the activity in vitro - J. Lijo, N. Vijay, H. J. Dechamma and G. R. Reddy

Veterinary World, 9(2): 160-165



   doi: 10.14202/vetworld.2016.160-165



J. Lijo: FMD Research Laboratory, Indian Veterinary Research Institute, Hebbal, Bengaluru, Karnataka, India;

N. Vijay: FMD Research Laboratory, Indian Veterinary Research Institute, Hebbal, Bengaluru, Karnataka, India;

H. J. Dechamma: FMD Research Laboratory, Indian Veterinary Research Institute, Hebbal, Bengaluru, Karnataka, India;

G. R. Reddy: FMD Research Laboratory, Indian Veterinary Research Institute, Hebbal, Bengaluru, Karnataka, India;


Received: 28-09-2015, Revised: 26-12-2015, Accepted: 31-12-2015, Published online: 13-02-2016


Corresponding author: G. R. Reddy, e-mail:

Citation: Lijo J, Vijay N, Dechamma HJ, Reddy GR (2016) Expression of biologically active bovine interleukin 7 and evaluating the activity in vitro, Veterinary World 9(2); 160-165.

Aim: Interleukin 7 (IL-7) is a ϒc family cytokine involved in the homeostatic proliferation and maintenance of immune cells. In the present study, we report the expression of bovine IL-7 (bIL-7) in Escherichia coli and evaluated for its biological activity.

Materials and Methods: The sequence coding for bIL-7 (mature protein) was amplified from primary bovine kidney cell culture and cloned into pET28-a vector and expressed in E.coli (BL 21 DE3). The expressed protein was purified by nickel-nitrilotriacetatechromatography, and the reactivity of the protein was confirmed by western blotting using monoclonal antibodies raised against human IL-7. The biological activity of expressed bIL-7 was evaluated by analyzing its effect on the expression of a nuclear factor for activated T-cells c1 (NFATc1), B-cell lymphoma 2 (Bcl2), suppressor of cytokine signaling 3 (SOCS3) molecules in bovine peripheral blood mononuclear cells (PBMCs) by quantitative polymerase chain reaction. Ability of the expressed protein was also analyzed by its effect on phosphorylating signal transducer and activator 3 (STAT3) molecule by immunostaining in human embryonic kidney cells 293 (HEK293) cells.

Results: The bIL-7 was able to induce the expression of Bcl2 and NFATc1expression in bovine PBMCs by 7 and 5-folds, respectively, whereas a 2-fold decrease was observed in the case of SOCS3 expression. Immunostaining studies in HEK293 cells using antihuman phospho-STAT3 showed activation and nuclear translocation of STAT3 molecule on bIL-7 treatment.

Conclusion: bIL-7 gene was successfully amplified, cloned, and expressed in a prokaryotic expression system. The biological activity study showed that the E.coli expressed bIL-7 protein is biologically active. Considering the role of IL-7 in T-cell homeostasis and memory cell generation, this molecule can be used for enhancing the vaccine response and that has to be proved by further experiments.

Keywords: B-cell lymphoma 2, nuclear factor for activated T-cells c1, recombinant bovine interleukin 7, signal transducer and activator 3.

1. Jiang, Q., Li, Q.W., Aiello, F.B., Mazzucchelli, R., Asefa, B., Annette, R., Khaled, A.R. and Durum, S.K. (2005) Cell biology of IL-7, a key lymphotropin. Cytokine Growth F R., 16: 513-533.
2. Amos, C.L., Woetmann, A., Nielsen, M., Geisler, C., Odum, N., Brown, B.L. and Dobson, P.R.M. (1998) Therole of caspase 3 and BclxL in the action of interleukin 7 (IL-7): A survival factor in activated human T cells. Cytokine, 10:662-668.
3. Mazzucchelli, R. and Durum, S.K. (2007) Interleukin-7 receptor expression: Intelligent design. Nat. Rev.Immunol., 7:144-154.
4. Seckinger, P. andFougereau, M. (1994) Activation of src family kinases in human pre-B cells by IL-7. J.Immunol., 153: 97-109.
5. VonFreeden-Jeffry, U., Vieira, P., Lucian, L.A., McNeil, T., Burdach, S.E. and Murray, R. (1995) Lymphopenia in interleukin (IL)-7 gene-deleted mice identifies IL-7 as a non redundant cytokine. J. Exp. Med., 181:1519-1526.
6. Chetoui, N., Boisvert, M., Gendron, S. andAoudjit, F. (2009) Interleukin 7 promotes the survival of human CD4+ effector/memory T cells by up- regulating Bcl-2 proteins and activating the JAK/STAT signaling pathway. Immunology, 130: 418-426.
PMid:20465565 PMCid:PMC2913221
7. Opferman, J.T., Letai, A., Beard, C., Sorcinelli, M.D., Ong, C.C. andKorsmeyer, S.J. (2003) Development and maintenance of B and T lymphocytes requires antiapoptotic MCL-1. Nature, 426:671-676.
8. Rathmell, J.C., Farkash, E.A., Gao, W. and Thompson, C.B.(2001) IL-7 enhances the survival and maintains the size of naive T cells. J.Immunol., 167:6869-6876.
9. Khaled, A.R. andDurum, S.K. (2003) Death and baxes: Mechanisms of lymphotrophic cytokines. Immunol. Rev., 193:48-57.
10. Bradley, L.M., Haynes, L. and Swain, S.L. (2005) IL-7: Maintaining T-cell memory and achieving homeostasis. Trends Immunol, 26(3): 172-176.
11. Cui, G., Staron, M.M., Gray, S.M., Ho, P.C., Amezquita, R.A., Wu, J. and Kaech, S.M. (2015) IL-7 induced glycerol transport and TAG synthesis promotes memory CD8+ T cells longevity. Cell, 161: 750-761.
PMid:25957683 PMCid:PMC4704440
12. McElory, C.A., Holland, P.J., Zhao, P., Lim, J.M., Wells, L., Eisenstein, E. and Walsh, S.T.R. (2012) Structural reorganization of the interleukin-7 signaling complex. Proc. Nat. Acad. Sci.,109(7): 2503-2508.
PMid:22308406 PMCid:PMC3289338
13. Livak, K.J. andSchmittgen, T.D. (2001) Analysis of relative gene expression data using real time quantitative PCR and the 2-∆∆cT method. Methods, 25: 402-402.
14. Greyson, J.M., Zajac, A.J.A. and Ahmed, R. (2000) Increased expression of Bcl2 in antigen specific memory CD8+ T cells. J.Immunol., 164: 3950-3954.
15. Serfling, E., Siebelt, F.B., Chuvpilo, S., Jankevies, E., Hessling, S.K., Twardzik, K.T. andAvots, A. (2000) The role of NF-AT transcription factors in T cell activation and differentiation. Biochem.Biophys.Acta, 1498: 1-18.
16. Macian, F. (2005) NFAT proteins: Key regulators of T-cell development and function. Nat.Rev.Immunol.,5: 472-484.
17. Patra, A.K., Avots, A., Zahedi, R.P., Schuler, T., Sickmann, A., Bommhardt, U. andSerfling, E. (2013)An alternative NFATC-activation pathway mediated by IL-7 is critical for early thymocyte development. Nat.Immunol., 14: 127-135.
18. Pellegrini, M., Calzascia, T., Toe, J.G., Preston, S.P., Lin, A.E., Elford, A.R., Shahinian,A., Lang, P.A., Morre, M., Assouline, B., Lahl,K., Sparwasser, T., Tedder,T.F., Paik, J.H., Depinho, R.A., Basta, S., Ohashi, P.S. andMak, T.W. (2011) IL-7 engages multiple mechanisms to overcome chronic viral infection and limit organ pathology. Cell, 144: 601-613.
19. Chou, W.C., Levy, D.E. and Lee, C.K. (2006) STAT3 positively regulates an early step in B cell development. Blood, 108(9): 3005-3011.
PMid:16825489 PMCid:PMC1895520
20. Michel, M.L., Pang, D.J., Haque, S.F.Y., Potocnik, A.J., Pennington, D.J. andHayday, A.C. (2012) Interleukin 7 (IL-7) selectively promotes mouse and human IL-17 producing ϒδ cell. Proc. Nat. Acad. Sci., 109(43): 17549-17554.
PMid:23047700 PMCid:PMC3491488
21. Hand, T.W., Cui, W., Jung, Y.W., Sefik, E., Joshi, N.S., Chandele, A., Liu, Y. and Kaech, S.M. (2010) Differential effects of STAT5 and PI3/AKT signalling on effector and memory CD8 T cell survival. Proc. Nat. Acad. Sci.,107(38): 16601-16606.
PMid:20823247 PMCid:PMC2944719
22. Park, S.H., Song,M.Y., Nam, H.J., Im, S.J. and Sung, Y.C. (2010)Codelivery of IL-7 augments multigenic HCV DNA vaccine induced antibody as well as broad T cel response in cynomolgus monkeys. Immune Netw.,10(6):198-205.
PMid:21286380 PMCid:PMC3026939
23. Seo, Y.B., Im, S.J., Namkoong, H., Kim, S.W., Choi, Y.W., Kang, M.C., Lim, H.S., Jin, H.T., Yang, S.H., Cho, M.L., Kim, Y.M., Lee, S.W., Choi, Y.K., Surh, C.D. and Sung, Y.C. (2014) Crucial role of IL-7 in the development of T follicular helper T cells as well as the induction of humoral immunity. J.Virol.,88(16): 8998-9009.
PMid:24899182 PMCid:PMC4136280
24. Limaye, A., Iketani, A., Boohaker, R., Oyer, J., Nemec, K., Solh, M., Copik, A. and Khaled, A.R. (2013) A modified IL-7 protein is a potent agent for immune reconstitution. Cytokine, 63(3): 282.
25. Kimura, M.Y., Pobezinsky, L.A., Guinter, T.I., Thomas, J., Adams, A., Park, J.H., Tai, X. and Singer, A. (2013) IL-7 signalling must be intermittent, not continuous, during CD8+ T cell homeostasis to promote cell survival instead of cell death. Nat. Immunol., 14(2):143-151.
PMid:23242416 PMCid:PMC3552087