Recombinant mouse cytomegalovirus expressing a ligand for the NKG2D receptor is attenuated and has improved vaccine properties
Irena Slavuljica, … , Astrid Krmpotić, Stipan Jonjić
Irena Slavuljica, … , Astrid Krmpotić, Stipan Jonjić
Published November 22, 2010
Citation Information: J Clin Invest. 2010;120(12):4532-4545. https://doi.org/10.1172/JCI43961.
View: Text | PDF
Research Article

Recombinant mouse cytomegalovirus expressing a ligand for the NKG2D receptor is attenuated and has improved vaccine properties

Abstract

Human CMV (HCMV) is a major cause of morbidity and mortality in both congenitally infected and immunocompromised individuals. Development of an effective HCMV vaccine would help protect these vulnerable groups. NK group 2, member D (NKG2D) is a potent activating receptor expressed by cells of the innate and adaptive immune systems. Its importance in HCMV immune surveillance is indicated by the elaborative evasion mechanisms evolved by the virus to avoid NKG2D. In order to study this signaling pathway, we engineered a recombinant mouse CMV expressing the high-affinity NKG2D ligand RAE-1γ (RAE-1γMCMV). Expression of RAE-1γ by MCMV resulted in profound virus attenuation in vivo and lower latent viral DNA loads. RAE-1γMCMV infection was efficiently controlled by immunodeficient hosts, including mice lacking type I interferon receptors or immunosuppressed by sublethal γ-irradiation. Features of MCMV infection in neonates were also diminished. Despite tight innate immune control, RAE-1γMCMV infection elicited strong and long-lasting protective immunity. Maternal RAE-1γMCMV immunization protected neonatal mice from MCMV disease via placental transfer of antiviral Abs. Despite strong selective pressure, the RAE-1γ transgene did not exhibit sequence variation following infection. Together, our results indicate that use of a recombinant virus encoding the ligand for an activating NK cell receptor could be a powerful approach to developing a safe and immunogenic HCMV vaccine.

Authors

Irena Slavuljica, Andreas Busche, Marina Babić, Maja Mitrović, Iva Gašparović, Đurđica Cekinović, Elitza Markova Car, Ester Pernjak Pugel, Ana Ciković, Vanda Juranić Lisnić, William J. Britt, Ulrich Koszinowski, Martin Messerle, Astrid Krmpotić, Stipan Jonjić

×

Figure 3

Comparable kinetics and phenotype of MCMV-specific memory CD8+ T cells in RAE-1γMCMV–, WT MCMV–, and Δm152 MCMV–infected mice.

Options: View larger image (or click on image) Download as PowerPoint
Comparable kinetics and phenotype of MCMV-specific memory CD8+ T cells i...
(A) BALB/c mice were f.p. injected with 2 × 105 PFU RAE-1γMCMV, WT MCMV, or Δm152 MCMV. Splenocytes were isolated at different times after infection and stained with IE1/m123 or m164 MHC class I tetramers and anti-CD8 Ab. The percentage of tetramer-specific CD8+ T cells for individual mice (circles) and median values (horizontal bars) are shown. (B) Splenocytes were isolated 9 months p.i. and stained with IE1/m123 MHC class I tetramer, anti-CD8 Ab, and Abs to indicated cell surface molecules. The percentage of IE1/m123-specific CD8+ T cells displaying effector memory (Tem) or central memory (Tcm) phenotype (left) and the percentage of Tem- and Tcm-expressing indicated cell surface molecules are shown (right). Error bars show mean ± SEM. (C) Representative histogram showing NKG2D staining on IE1/m123-specific CD8+ T cells in spleen 9 months after WT MCMV (filled histogram) or RAE-1γMCMV (dotted line) infection. Tetramer-negative CD8+ T cells are indicated by the dashed line. (D) Splenocytes were isolated 9 months p.i. and stained with the indicated tetramers or stimulated with the indicated peptides and stained for IFN-γ production or (E) costained for IFN-γ and TNF-α production. Splenocytes were stimulated as above in the presence of the anti-CD107a Ab and costained for IFN-γ production. (D and E) Representative dot plots gated on CD8+ T cells of 3 mice per group are shown. Numbers indicate means. Results from 1 of 2 similar experiments are shown.