Cellular immune responses of BALB/c mice induced by intramuscular injection of PRRSV-ORF5 DNA vaccine with different doses

Abstract

BALB/c mice were immunized with 50 µg, 100 µg, 200 µg of pcDNA-PRRSV-ORF5 DNA vaccine respectively by intramuscular injection, with PBS and pcDNA3.1(+) as controls. Fluorescence activated cell Sorter (FACS) was used to detect the number of CD⁺₄ and CD⁺₈ T-lymphocytes. T-lymphocyte proliferation test was used to detect proliferation of the T-lymphocyte cells in peripheral blood lymphocytes of mice vaccinated with pcDNA-PRRSV-ORF5 DNA vaccine. The results showed that the difference in ConA response to T-lymphocytes in blood was highly significant between all experimental groups and the control group (P<0.01). The number of CD₄⁺ T-lymphocytes in experimental groups was significantly higher than that of the control group 7 d after vaccination. The number of CD₈⁺ T-lymphocytes in the experimental groups was higher than that of the control group 28 d after vaccination. Mice immunized with a higher dose (200 µg) of DNA vaccine demonstrated higher cellular immune response than those immunized with a lower dose (100 µg, 50 µg) of DNA vaccine. The results demonstrated that pcDNA-PRRSV-ORF5 DNA vaccine could induce a good cellular immune response which may be dose-dependent.

Keywords

PRRSV / ORF5 DNA vaccine / cellular immune response / mice

References

[1] Barry M A, Johnston S A (1997). Biological features of genetic immunization. Vaccine, 15(8): 788-791

[2] Cohen J (1993). Naked DNA points way to vaccines. Science, 259(5102): 1691-1692

[3] Davis H L, Brazolot Millan C L, Mancini M, McCluskie M J, Hadchouel M, Comanita L, Tiollais P, Whalen R G, Michel M L (1997). DNA-based immunization against hepatitis B surface antigen (HBsAg) in normal and HBsAg-transgenic mice. Vaccine, 15(8): 849-852

[4] Doolan D L, Sedegah M, Hedstrom R C, Hobart P, Charoenvit Y, Hoffman S L (1996). Circumventing genetic restriction of protection against malaria with multigene DNA immunization: CD8+ cell-, interferon gamma-, and nitric oxide-dependent immunity. J Exp Med, 183(4): 1739-1746

[5] Feng W H, Tompkins M B, Xu J S, Zhang H X, McCaw M B (2003). Analysis of constitutive cytokine expression by pigs infected in-utero with porcine reproductive and respiratory syndrome virus. Vet Immunol Immunopathol, 94(1-2): 35-45

[6] Gong F L (2000). Medical Immunology. Beijing: Science Press, 6 (in Chinese)

[7] Goyal S M (1993). Porcine reproductive and respiratory syndrome. J Vet Diagn Invest, 5(4): 656-664

[8] Jin B Q (2002). The Cell and Molecule Immunology Experimental Technique. Xi’an: Publishing House of the Fourth Army Medical University, 61-65 (in Chinese)

[9] Keffaber K K (1989). Reproductive failure of unknown etiology. Am Assoc Swine Pract Newsletter, (1): 1-9

[10] Krieg A M, Yi A K, Schorr J, Davis, H L (1998). The role of CpG dinucleotides in DNA vaccines. Trends Microbiol, 6(1): 23-27

[11] Liu M, Ma H, Li B Q (1999). Investigation of detecting murine lymphocyte proliferate response by MTT assay. Chinese Journal of Laboratory Animal Science, 9(3):146-149 (in Chinese)

[12] Liu Y B (1989). Animal’s Immunology Experimental Technique. Changchun: The Science Tech Publishing House of Jilin, 226-330 (in Chinese)

[13] Manickan E, Rouse R J, Wire W S, Rouse B T (1995). Genetic immunization against herpes simplex virus. Protection is mediated by CD4+ T-lymphocytes. Journal of Immunology, 155: 259-265

[14] Shimizu M, Yamada S, Kawashima K, Ohashi S, Shimizu S, Ogawa T (1996). Changes of lymphocyte subpopulations in pigs infected with porcine reproductive and respiratory syndrome (PRRS) virus. Vet Immunol Immunopathol, 50(1-2): 19-27

[15] Shin J H, Kang Y B, Kim Y J (1993). Sero-epidemiological studies on porcine reproductive and respiratory syndrome in Korea. I. Detection of indirect fluorescent antibodies. RDA J Agri Sci, 35: 572-576

[16] Wensvoort G (1994). Porcine epidemic abortion and respiratory syndrome. In: Proc 13th Int Pig Vet Soci Congr. Bangkok, Thailand: 1994, 11-14

[17] Xiong Y L, Liu H P, Zu P, Jia Y Z, Zhang Y J (2003). Modulatory function of high dose hepatitis B surface antigen vaccine to cellular immune responses in mice. Chinese Journal of Pathophysiology, 19(9): 1250-1252 (in Chinese)

[18] Yankauckas M A, Morrow J E, Parker S E, Abai A, Rhodes G H, Dwarki V J, Gromkowski S H (1993). Long-term anti-nucleoprotein cellular and humoral immunity is induced by intramuscular injection of plasmid DNA containing NP gene. DNA Cell Biol, (12): 771-776

[19] Zelphati O, Nguyen C, Ferrari M, Felgner J, Tsai Y, Felgner P L (1998). Stable and monodisperse lipoplex formulations for gene delivery. Gene Ther, 5(9): 1272-1282

[20] Zeng Y, Wang E H, Yi X R, Zhang Y J (2003). Research on immunoresponse of mice by different dose recombinant (yeast) hepatitis B vaccine. China Pharmacist, 6(9): 532-534 (in Chinese)

Acknowledgements

This work was supported by Sichuan Bio-tech Project (No. 01NG018-03), the National State Key Program Project of Science and Technology (No. 2004BA901A03), Program for New Century Excellent Talents in University, Ministry of Education, China (No. NCET-04-0906).

RIGHTS & PERMISSIONS

2007 Higher Education Press