scholarly journals Comparative Evaluation of the Vaccine Efficacies of Three Adenovirus-Based Vector Types in the Friend Retrovirus Infection Model

2019 ◽  
Vol 93 (21) ◽  
Author(s):  
Camilla Patrizia Hrycak ◽  
Sonja Windmann ◽  
Wibke Bayer

ABSTRACT Adenovirus (AdV)-based vectors are popular experimental vaccine vectors, but despite their ability to induce strong immune responses, their application is impeded by widespread preexisting immunity against many AdV types that can impair or even abrogate the induction of transgene-specific immune responses. Therefore, the development of vectors based on AdV types with a low seroprevalence is important for effective AdV-based immunization in humans. We investigated the immunization efficacy of vectors based on AdV type 48 (Ad48) and Ad50 in the ovalbumin (ova) model as well as the Friend retrovirus (FV) model, which allows testing of the protective effect of vaccine-induced immunity. Using ova-encoding vectors, we found a significantly lower induction of ova-specific CD8+ T cells and antibody responses by Ad48- and Ad50-based vectors than by Ad5-based vectors. Similarly, we found a reduced induction of FV-specific CD8+ T cell responses in Ad48- and Ad50.Leader-Gag-immunized mice compared with that in Ad5-immunized mice; however, some of those mice were able to control the FV infection, and protection correlated with the level of neutralizing antibodies 10 days after FV challenge. Analyses of the AdV-specific antibodies and CD8+ T cells induced by the individual AdV types revealed a high level of cross-reactivity, and the efficacy of Ad48-based immunization was impaired in Ad5-preimmune mice. Our results show that the immunity induced by Ad48- and Ad50-based vectors is reduced compared to that induced by Ad5 and is sufficient to control FV infection in only some of the immunized mice. A high level of cross-reactivity suggests that AdV preimmunity must be considered even when applying rare AdV-based vectors. IMPORTANCE AdV-based vectors are important tools for the development of vaccines against a wide range of pathogens. While AdV vectors are generally considered safe and highly effective, their application can be severely impaired by preexisting immunity due to the widespread seroprevalence of some AdV types. The characterization of different AdV types with regard to immunogenicity and efficacy in challenge models is of great importance for the development of improved AdV-based vectors that allow for efficient immunization despite anti-AdV immunity. We show that the immunity induced by an Ad48-based vector is inferior to that induced by an Ad5-based vector but can still mediate the control of an FV infection in highly FV-susceptible mice. However, the efficacy of Ad48-based immunization was impaired in Ad5-preimmune mice. Importantly, we found cross-reactivity of both the humoral and cellular immune responses raised by the individual AdV types, suggesting that switching to a different AdV type may not be sufficient to circumvent preexisting anti-AdV immunity.

2021 ◽  
Author(s):  
Tina Schmidt ◽  
Verena Klemis ◽  
David Schub ◽  
Janine Mihm ◽  
Franziska Hielscher ◽  
...  

Heterologous priming with the ChAdOx1-nCoV-19 vector-vaccine followed by boosting with an mRNA-vaccine is currently recommended in Germany, although data on immunogenicity and reactogenicity are not available. Here we show that the heterologous regimen induced spike-specific IgG, neutralizing antibodies, and spike-specific CD4 T-cells, which were significantly more pronounced than after homologous vector boost, and higher or comparable in magnitude to the homologous mRNA regimens. Moreover, spike-specific CD8 T-cell levels after heterologous vaccination were significantly higher than after both homologous regimens. Cytokine expression profiling showed a predominance of polyfunctional T-cells expressing IFNγ, TNFα and IL-2 with subtle differences between regimens. Both recipients of the homologous vector-regimen and the heterologous vector/mRNA-combination were most affected by the priming vector-vaccination, whereas heterologous boosting was well tolerated and comparable to homologous mRNA-boosting. Taken together, heterologous vector-mRNA boosting induces strong humoral and cellular immune responses with acceptable reactogenicity profile. This knowledge will have implications for future vaccine strategies.


2021 ◽  
Author(s):  
Tina Schmidt ◽  
Verena Klemis ◽  
David Schub ◽  
Janine Mihm ◽  
Franziska Hielscher ◽  
...  

AbstractHeterologous priming with the ChAdOx1 nCoV-19 vector vaccine followed by boosting with a messenger RNA vaccine (BNT162b2 or mRNA-1273) is currently recommended in Germany, although data on immunogenicity and reactogenicity are not available. In this observational study we show that, in healthy adult individuals (n = 96), the heterologous vaccine regimen induced spike-specific IgG, neutralizing antibodies and spike-specific CD4 T cells, the levels of which which were significantly higher than after homologous vector vaccine boost (n = 55) and higher or comparable in magnitude to homologous mRNA vaccine regimens (n = 62). Moreover, spike-specific CD8 T cell levels after heterologous vaccination were significantly higher than after both homologous regimens. Spike-specific T cells were predominantly polyfunctional with largely overlapping cytokine-producing phenotypes in all three regimens. Recipients of both the homologous vector regimen and the heterologous vector/mRNA combination reported greater reactogenicity following the priming vector vaccination, whereas heterologous boosting was well tolerated and comparable to homologous mRNA boosting. Taken together, heterologous vector/mRNA boosting induces strong humoral and cellular immune responses with acceptable reactogenicity profiles.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Alexandra J. Spencer ◽  
Paul F. McKay ◽  
Sandra Belij-Rammerstorfer ◽  
Marta Ulaszewska ◽  
Cameron D. Bissett ◽  
...  

AbstractSeveral vaccines have demonstrated efficacy against SARS-CoV-2 mediated disease, yet there is limited data on the immune response induced by heterologous vaccination regimens using alternate vaccine modalities. Here, we present a detailed description of the immune response, in mice, following vaccination with a self-amplifying RNA (saRNA) vaccine and an adenoviral vectored vaccine (ChAdOx1 nCoV-19/AZD1222) against SARS-CoV-2. We demonstrate that antibody responses are higher in two-dose heterologous vaccination regimens than single-dose regimens. Neutralising titres after heterologous prime-boost were at least comparable or higher than the titres measured after homologous prime boost vaccination with viral vectors. Importantly, the cellular immune response after a heterologous regimen is dominated by cytotoxic T cells and Th1+ CD4 T cells, which is superior to the response induced in homologous vaccination regimens in mice. These results underpin the need for clinical trials to investigate the immunogenicity of heterologous regimens with alternate vaccine technologies.


Blood ◽  
2003 ◽  
Vol 101 (3) ◽  
pp. 807-814 ◽  
Author(s):  
James W. Lillard ◽  
Udai P. Singh ◽  
Prosper N. Boyaka ◽  
Shailesh Singh ◽  
Dennis D. Taub ◽  
...  

AbstractMacrophage inflammatory protein-1α (MIP-1α) and MIP-1β are distinct but highly homologous CC chemokines produced by a variety of host cells in response to various external stimuli and share affinity for CCR5. To better elucidate the role of these CC chemokines in adaptive immunity, we have characterized the affects of MIP-1α and MIP-1β on cellular and humoral immune responses. MIP-1α stimulated strong antigen (Ag)–specific serum immunoglobulin G (IgG) and IgM responses, while MIP-1β promoted lower IgG and IgM but higher serum IgA and IgE antibody (Ab) responses. MIP-1α elevated Ag-specific IgG1 and IgG2b followed by IgG2a and IgG3 subclass responses, while MIP-1β only stimulated IgG1 and IgG2b subclasses. Correspondingly, MIP-1β produced higher titers of Ag-specific mucosal secretory IgA Ab levels when compared with MIP-1α. Splenic T cells from MIP-1α– or MIP-1β–treated mice displayed higher Ag-specific Th1 (interferon-γ [IFN-γ]) as well as selective Th2 (interleukin-5 [IL-5] and IL-6) cytokine responses than did T cells from control groups. Interestingly, mucosally derived T cells from MIP-1β–treated mice displayed higher levels of IL-4 and IL-6 compared with MIP-1α–treated mice. However, MIP-1α effectively enhanced Ag-specific cell-mediated immune responses. In correlation with their selective effects on humoral and cellular immune responses, these chemokines also differentially attract CD4+ versus CD8+ T cells and modulate CD40, CD80, and CD86 expressed by B220+ cells as well as CD28, 4-1BB, and gp39 expression by CD4+ and CD8+ T cells in a dose-dependent fashion. Taken together, these studies suggest that these CC chemokines differentially enhance mucosal and serum humoral as well as cellular immune responses.


Blood ◽  
2011 ◽  
Vol 118 (25) ◽  
pp. 6499-6505 ◽  
Author(s):  
Edgardo D. Carosella ◽  
Silvia Gregori ◽  
Joel LeMaoult

Abstract Myeloid antigen-presenting cells (APCs), regulatory cells, and the HLA-G molecule are involved in modulating immune responses and promoting tolerance. APCs are known to induce regulatory cells and to express HLA-G as well as 2 of its receptors; regulatory T cells can express and act through HLA-G; and HLA-G has been directly involved in the generation of regulatory cells. Thus, interplay(s) among HLA-G, APCs, and regulatory cells can be easily envisaged. However, despite a large body of evidence on the tolerogenic properties of HLA-G, APCs, and regulatory cells, little is known on how these tolerogenic players cooperate. In this review, we first focus on key aspects of the individual relationships between HLA-G, myeloid APCs, and regulatory cells. In its second part, we highlight recent work that gathers individual effects and demonstrates how intertwined the HLA-G/myeloid APCs/regulatory cell relationship is.


2008 ◽  
Vol 15 (3) ◽  
pp. 452-459 ◽  
Author(s):  
Giulia Freer ◽  
Donatella Matteucci ◽  
Paola Mazzetti ◽  
Francesca Tarabella ◽  
Valentina Catalucci ◽  
...  

ABSTRACT Dendritic cells are the only antigen-presenting cells that can present exogenous antigens to both helper and cytolytic T cells and prime Th1-type or Th2-type cellular immune responses. Given their unique immune functions, dendritic cells are considered attractive “live adjuvants” for vaccination and immunotherapy against cancer and infectious diseases. The present study was carried out to assess whether the reinjection of autologous monocyte-derived dendritic cells loaded with an aldithriol-2-inactivated primary isolate of feline immune deficiency virus (FIV) was able to elicit protective immune responses against the homologous virus in naive cats. Vaccine efficacy was assessed by monitoring immune responses and, finally, by challenge with the homologous virus of vaccinated, mock-vaccinated, and healthy cats. The outcome of challenge was followed by measuring cellular and antibody responses and viral and proviral loads and quantitating FIV by isolation and a count of CD4+/CD8+ T cells in blood. Vaccinated animals exhibited clearly evident FIV-specific peripheral blood mononuclear cell proliferation and antibody titers in response to immunization; however, they became infected with the challenge virus at rates comparable to those of control animals.


2020 ◽  
Vol 94 (24) ◽  
Author(s):  
Mauricio A. Martins ◽  
Lucas Gonzalez-Nieto ◽  
Michael J. Ricciardi ◽  
Varian K. Bailey ◽  
Christine M. Dang ◽  
...  

ABSTRACT Given the complex biology of human immunodeficiency virus (HIV) and its remarkable capacity to evade host immune responses, HIV vaccine efficacy may benefit from the induction of both humoral and cellular immune responses of maximal breadth, potency, and longevity. Guided by this rationale, we set out to develop an immunization protocol aimed at maximizing the induction of anti-Envelope (anti-Env) antibodies and CD8+ T cells targeting non-Env epitopes in rhesus macaques (RMs). Our approach was to deliver the entire simian immunodeficiency virus (SIV) proteome by serial vaccinations. To that end, 12 RMs were vaccinated over 81 weeks with DNA, modified vaccinia Ankara (MVA), vesicular stomatitis virus (VSV), adenovirus type 5 (Ad5), rhesus monkey rhadinovirus (RRV), and DNA again. Both the RRV and the final DNA boosters delivered a near-full-length SIVmac239 genome capable of assembling noninfectious SIV particles and inducing T-cell responses against all nine SIV proteins. Compared to previous SIV vaccine trials, the present DNA-MVA-VSV-Ad5-RRV-DNA regimen resulted in comparable levels of Env-binding antibodies and SIV-specific CD8+ T-cells. Interestingly, one vaccinee developed low titers of neutralizing antibodies (NAbs) against SIVmac239, a tier 3 virus. Following repeated intrarectal marginal-dose challenges with SIVmac239, vaccinees were not protected from SIV acquisition but manifested partial control of viremia. Strikingly, the animal with the low-titer vaccine-induced anti-SIVmac239 NAb response acquired infection after the first SIVmac239 exposure. Collectively, these results highlight the difficulties in eliciting protective immunity against immunodeficiency virus infection. IMPORTANCE Our results are relevant to HIV vaccine development efforts because they suggest that increasing the number of booster immunizations or delivering additional viral antigens may not necessarily improve vaccine efficacy against immunodeficiency virus infection.


Cancers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 3044 ◽  
Author(s):  
Peter Kok-Ting Wan ◽  
Michelle Kwan-Yee Siu ◽  
Thomas Ho-Yin Leung ◽  
Xue-Tang Mo ◽  
Karen Kar-Loen Chan ◽  
...  

Nuclear receptor related-1 protein (Nurr1), coded by an early response gene, is involved in multiple cellular and physiological functions, including proliferation, survival, and self-renewal. Dysregulation of Nurr1 has been frequently observed in many cancers and is attributed to multiple transcriptional and post-transcriptional mechanisms. Besides, Nurr1 exhibits extensive crosstalk with many oncogenic and tumor suppressor molecules, which contribute to its potential pro-malignant behaviors. Furthermore, Nurr1 is a key player in attenuating antitumor immune responses. It not only potentiates immunosuppressive functions of regulatory T cells but also dampens the activity of cytotoxic T cells. The selective accessibility of chromatin by Nurr1 in T cells is closely associated with cell exhaustion and poor efficacy of cancer immunotherapy. In this review, we summarize the reported findings of Nurr1 in different malignancies, the mechanisms that regulate Nurr1 expression, and the downstream signaling pathways that Nurr1 employs to promote a wide range of malignant phenotypes. We also give an overview of the association between Nurr1 and antitumor immunity and discuss the inhibition of Nurr1 as a potential immunotherapeutic strategy.


Sign in / Sign up

Export Citation Format

Share Document