Recombined DNA vaccines encoding calreticulin linked to HPV6bE7 enhance immune response and inhibit angiogenic activity in B16 melanoma mouse model expressing HPV 6bE7 antigen

Arch Dermatol Res. 2006 Jul;298(2):64-72. doi: 10.1007/s00403-006-0659-z. Epub 2006 Apr 27.

Abstract

Calreticulin (CRT) has been reported to have an effect of upregulating MHC class I presentation as well as inhibiting angiogenesis in vitro and in vivo. Combination of dual mechanisms of enhanced immunogenicity of human papillomavirus (HPV) 6bE7 antigen and antiangiogenesis may be introduced in the strategy of vaccines against condyloma acuminatum (CA) resulting from HPV infection. Therefore, we constructed DNA vaccines by employing different lengths of CRT chimerically linked to a model antigen HPV6bE7 and investigated the immunological and antiangiogenic effects of these vaccines in a B16 melanoma model that express HPV6bE7 antigen. Our results showed that vaccination with CRT180/HPV6bE7 or CRT120/HPV6bE7 enhanced the presence of CD8(+) T cells and TCRgammadelta T cells in vivo, increased the specific lysis activity against E7-expressing cells and secretion levels of IL-2 and IFN-gamma by activating T cells in vitro significantly. Moreover, recombined CRT180 or CRT120 with HPV6bE7 vaccines could elicit a more efficient E7-specific immune response than HPV6bE7 alone. The similarity of immunological enhancement of CRT180/HPV6bE7 and CRT120/HPV6bE7 implies that the immunologically active region mainly exist in fragment 1-120 aa. Furthermore, CRT180/HPV6bE7 and CRT180 displayed remarkable superiority over CRT120/HPV6bE7 in vivo angiogenesis assay, suggesting that the antiangiogenic activity of CRT resides in a domain between aa 120 and 180. Vaccination with CRT180/HPV6bE7 generated the best protective effect of delaying tumor formation and reduction of tumor size in tumor growth inhibition experiment among all DNA constructs. Therefore, CRT180/HPV6bE7 vaccine may enhance the immunological response to HPV6bE7 and inhibit angiogenesis. This construct may be useful in preventing HPV-associated dermatosis and may be developed as a promising strategy to control CA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Viral / genetics
  • Base Sequence
  • Calbindin 2
  • Cell Line, Tumor
  • Condylomata Acuminata / immunology
  • Condylomata Acuminata / pathology
  • Condylomata Acuminata / therapy
  • DNA Primers / genetics
  • Female
  • Human papillomavirus 6 / genetics*
  • Human papillomavirus 6 / immunology*
  • Human papillomavirus 6 / pathogenicity
  • Humans
  • Interferon-gamma / biosynthesis
  • Interleukin-2 / biosynthesis
  • Melanoma, Experimental / blood supply
  • Melanoma, Experimental / immunology*
  • Melanoma, Experimental / pathology
  • Melanoma, Experimental / therapy*
  • Mice
  • Mice, Inbred C57BL
  • Neovascularization, Pathologic / prevention & control
  • Oncogene Proteins, Viral / genetics*
  • Oncogene Proteins, Viral / immunology*
  • Plasmids / genetics
  • S100 Calcium Binding Protein G / genetics*
  • S100 Calcium Binding Protein G / immunology*
  • T-Lymphocytes, Cytotoxic / immunology
  • Transfection
  • Vaccines, DNA / genetics
  • Vaccines, DNA / pharmacology*
  • Viral Vaccines / genetics
  • Viral Vaccines / pharmacology*

Substances

  • Antigens, Viral
  • Calbindin 2
  • DNA Primers
  • E7 protein, Human papillomavirus 6b
  • Interleukin-2
  • Oncogene Proteins, Viral
  • S100 Calcium Binding Protein G
  • Vaccines, DNA
  • Viral Vaccines
  • Interferon-gamma