scholarly journals Mimicking Pathogens to Augment the Potency of Liposomal Cancer Vaccines

Pharmaceutics ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 954
Author(s):  
Maarten K. Nijen Twilhaar ◽  
Lucas Czentner ◽  
Cornelus F. van Nostrum ◽  
Gert Storm ◽  
Joke M. M. den Haan

Liposomes have emerged as interesting vehicles in cancer vaccination strategies as their composition enables the inclusion of both hydrophilic and hydrophobic antigens and adjuvants. In addition, liposomes can be decorated with targeting moieties to further resemble pathogenic particles that allow for better engagement with the immune system. However, so far liposomal cancer vaccines have not yet reached their full potential in the clinic. In this review, we summarize recent preclinical studies on liposomal cancer vaccines. We describe the basic ingredients for liposomal cancer vaccines, tumor antigens, and adjuvants, and how their combined inclusion together with targeting moieties potentially derived from pathogens can enhance vaccine immunogenicity. We discuss newly identified antigen-presenting cells in humans and mice that pose as promising targets for cancer vaccines. The lessons learned from these preclinical studies can be applied to enhance the efficacy of liposomal cancer vaccination in the clinic.

Vaccines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 668
Author(s):  
Howard Donninger ◽  
Chi Li ◽  
John W. Eaton ◽  
Kavitha Yaddanapudi

The advent of cancer immunotherapy has revolutionized the field of cancer treatment and offers cancer patients new hope. Although this therapy has proved highly successful for some patients, its efficacy is not all encompassing and several cancer types do not respond. Cancer vaccines offer an alternate approach to promote anti-tumor immunity that differ in their mode of action from antibody-based therapies. Cancer vaccines serve to balance the equilibrium of the crosstalk between the tumor cells and the host immune system. Recent advances in understanding the nature of tumor-mediated tolerogenicity and antigen presentation has aided in the identification of tumor antigens that have the potential to enhance anti-tumor immunity. Cancer vaccines can either be prophylactic (preventative) or therapeutic (curative). An exciting option for therapeutic vaccines is the emergence of personalized vaccines, which are tailor-made and specific for tumor type and individual patient. This review summarizes the current standing of the most promising vaccine strategies with respect to their development and clinical efficacy. We also discuss prospects for future development of stem cell-based prophylactic vaccines.


2021 ◽  
Author(s):  
Moataz Dowaidar

Cancer immunotherapy, which attempts to activate or stimulate the immune system to treat cancer, has become the standard of treatment. Although some cancer vaccines are efficiently translated, they have not yet reached the same degree of success as infectious disease immunizations. A primary factor is the low immunogenicity of the tumor and related antigens. Unlike viruses, cancer cells emerge from somatic mutations in patients' healthy tissues, making it harder for the immune system to properly detect tumor cells. Biogenic nanoparticles have recently been highlighted as a solution to address some of the issues with creating anticancer vaccinations. Antigens, medication delivery, and others all benefit from biogenic nanoparticles. Biogenic nanoparticles have long been researched as a vaccine. Biogenic nanoparticles-based platforms, like particular VLPs, inherently activate inflammatory responses and may be increased with TAAs evaluated for antigen-specific antitumor responses to patient malignancies. OMVs and OMV-coated nanoparticles can be multiantigenic and immunostimulative in the box. PAMPs present in OMVs can activate innate immunity while suppressing tumor development. A range of cells, including immune and malignant cells, produce exosomes and play a critical role in cell-to-cell communication. Exosomes may contain interesting materials such as specific drugs, proteins, DNA, and RNA species, and their function depends on host cells. In cancer vaccines, however, these biogenic nanoparticles still have some limitations. Transferring tumor antigens and adjuvants to the secondary lymphoid system is a critical issue for biogenic nanoparticles. OMVs lack tumor antigens. Adjuvants are low in VLPs and exosomes. Furthermore, enhancing the protective response of biogenic nanoparticles, generating protective antigens in these nanoparticles and reducing the toxicity of nanoparticles are all challenges in cancer immunotherapy. There has been a lot of information regarding biogenic nanoparticles created by a variety of bacteria or cells in the area of bacterial vesicle research for a long time, but there has been a dearth of in-depth study focused on identifying molecules crucial to biogenesis or biogenic nanoparticles. Many basic questions remain unanswered here. Which envelope factors release biogenic nanoparticles? What signals and mechanisms regulate biogenic biogenic nanoparticles? Understanding these and other concepts as a cancer immunotherapy delivery technique is vital for the future development of biogenic nanoparticles. Future investigations are anticipated to begin to address these fundamental issues and increase our knowledge.


2004 ◽  
Vol 19 (3) ◽  
pp. 213-220
Author(s):  
F. Battaini ◽  
D. Besusso ◽  
L. Sfondrini ◽  
A. Rossini ◽  
D. Morelli ◽  
...  

Dendritic cells (DCs) are the most potent antigen-presenting cells of the immune system capable of initiating immune responses to antigens. It is also well documented that cancer patients often experience anergy against tumor antigens. In this study we selected the best protocol for inducing the production of antibodies against the HER2 oncoprotein using DCs to overcome anergy. Murine DCs were pulsed in vitro, using different protocols, with recombinant HER2 fused to a human Fc (in order to improve DC antigen uptake) and were used to vaccinate mice. The obtained results indicate that antigen-pulsed DCs can induce an antibody response and that adding CpG after antigen pulsing greatly increases anti-HER2 antibody production.


2021 ◽  
Vol 13 (601) ◽  
pp. eabc2816
Author(s):  
Long Chen ◽  
Hao Qin ◽  
Ruifang Zhao ◽  
Xiao Zhao ◽  
Liangru Lin ◽  
...  

Cancer vaccines based on resected tumors from patients have gained great interest as an individualized cancer treatment strategy. However, eliciting a robust therapeutic effect with personalized vaccines remains a challenge because of the weak immunogenicity of autologous tumor antigens. Utilizing exogenous prokaryotic constituents that act as adjuvants to enhance immunogenicity is a promising strategy to overcome this limitation. However, nonspecific stimulation of the immune system may elicit an undesirable immunopathological state. To specifically trigger sufficient antitumor reactivity without notable adverse effects, we developed an antigen and adjuvant codelivery nanoparticle vaccine based on Escherichia coli cytoplasmic membranes (EMs) and tumor cell membranes (TMs) from resected autologous tumor tissue. Introduction of the EM into the hybrid membrane nanoparticle vaccines (HM-NPs) induced dendritic cell maturation, thus activating splenic T cells. HM-NPs showed efficacy in immunogenic CT26 colon and 4T1 breast tumor mouse models and also efficiently induced tumor regression in B16-F10 melanoma and EMT6 breast tumor mouse models. Furthermore, HM-NPs provoked a strong tumor-specific immune response, which not only extended postoperative animal survival but also conferred long-term protection (up to 3 months) against tumor rechallenge in a CT26 colon tumor mouse model. Specific depletion of different immune cell populations revealed that CD8+ T and NK cells were crucial to the vaccine-elicited tumor regression. Individualized autologous tumor antigen vaccines based on effective activation of the innate immune system by bacterial cytoplasmic membranes hold great potential for personalized treatment of postoperative patients with cancer.


2020 ◽  
Vol 6 (40) ◽  
pp. eabb5223
Author(s):  
Kaiyuan Ni ◽  
Guangxu Lan ◽  
Nining Guo ◽  
August Culbert ◽  
Taokun Luo ◽  
...  

Cancer vaccines have been actively pursued to bolster antitumor immunity. Here, we designed nanoscale metal-organic frameworks (nMOFs) as locally activable immunotherapeutics to release danger-associated molecular patterns (DAMPs) and tumor antigens and deliver pathogen-associated molecular patterns (PAMPs) for in situ personalized cancer vaccination. When activated by x-rays, nMOFs effectively generate reactive oxygen species to release DAMPs and tumor antigens while delivering CpG oligodeoxynucleotides as PAMPs to facilitate the maturation of antigen-presenting cells. Together, DAMPs, tumor antigens, and PAMPs expand cytotoxic T cells in tumor-draining lymph nodes to reinvigorate the adaptive immune system for local tumor regression. When treated in combination with an immune checkpoint inhibitor, the local therapeutic effects of nMOF-based vaccines were extended to distant tumors via attenuating T cell exhaustion. Our work demonstrates the potential of nMOFs as x-ray–activable in situ cancer vaccines to awaken the host’s innate and adaptive immune systems for systemic antitumor immunity.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Lei Miao ◽  
Yu Zhang ◽  
Leaf Huang

AbstractmRNA vaccines have become a promising platform for cancer immunotherapy. During vaccination, naked or vehicle loaded mRNA vaccines efficiently express tumor antigens in antigen-presenting cells (APCs), facilitate APC activation and innate/adaptive immune stimulation. mRNA cancer vaccine precedes other conventional vaccine platforms due to high potency, safe administration, rapid development potentials, and cost-effective manufacturing. However, mRNA vaccine applications have been limited by instability, innate immunogenicity, and inefficient in vivo delivery. Appropriate mRNA structure modifications (i.e., codon optimizations, nucleotide modifications, self-amplifying mRNAs, etc.) and formulation methods (i.e., lipid nanoparticles (LNPs), polymers, peptides, etc.) have been investigated to overcome these issues. Tuning the administration routes and co-delivery of multiple mRNA vaccines with other immunotherapeutic agents (e.g., checkpoint inhibitors) have further boosted the host anti-tumor immunity and increased the likelihood of tumor cell eradication. With the recent U.S. Food and Drug Administration (FDA) approvals of LNP-loaded mRNA vaccines for the prevention of COVID-19 and the promising therapeutic outcomes of mRNA cancer vaccines achieved in several clinical trials against multiple aggressive solid tumors, we envision the rapid advancing of mRNA vaccines for cancer immunotherapy in the near future. This review provides a detailed overview of the recent progress and existing challenges of mRNA cancer vaccines and future considerations of applying mRNA vaccine for cancer immunotherapies.


Author(s):  
Carsten Brunn ◽  
Takashi Kei Kishimoto

In recent months as vaccines against the SARS-CoV-2 virus continue to rollout across the globe, there has been a renewed interest in ways to activate or ignite the immune system. For a vaccine to be effective, it must be immunogenic and specific to provoke the body's defenses to mount an effective response that protects the host from disease. However, there are other situations wherein the immune system mounts an unwanted immune response that can be detrimental to health, either directly, by causing an autoimmune disease, or indirectly, by compromising the safety and/or efficacy of biologic drugs. In these scenarios, it would be desirable to have a ‘tolerogenic vaccine’ that could selectively and effectively mitigate these unwanted immune responses. ImmTORTM, a nanoparticle technology, is being developed to address the issue of immunogenicity for gene therapy vectors and other biologic drugs. By targeting antigen-presenting cells, ImmTORTM has the potential to amplify the efficacy of biologic therapies and unlock the full potential of such treatments to improve the lives of those who suffer from serious and debilitating diseases.


Vaccines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 409
Author(s):  
Enrique Gómez Alcaide ◽  
Sinduya Krishnarajah ◽  
Fabian Junker

Despite significant recent improvements in the field of immunotherapy, cancer remains a heavy burden on patients and healthcare systems. In recent years, immunotherapies have led to remarkable strides in treating certain cancers. However, despite the success of checkpoint inhibitors and the advent of cellular therapies, novel strategies need to be explored to (1) improve treatment in patients where these approaches fail and (2) make such treatments widely and financially accessible. Vaccines based on tumor antigens (Ag) have emerged as an innovative strategy with the potential to address these areas. Here, we review the fundamental aspects relevant for the development of cancer vaccines and the critical role of dendritic cells (DCs) in this process. We first offer a general overview of DC biology and routes of Ag presentation eliciting effective T cell-mediated immune responses. We then present new therapeutic avenues specifically targeting Fc gamma receptors (FcγR) as a means to deliver antigen selectively to DCs and its effects on T-cell activation. We present an overview of the mechanistic aspects of FcγR-mediated DC targeting, as well as potential tumor vaccination strategies based on preclinical and translational studies. In particular, we highlight recent developments in the field of recombinant immune complex-like large molecules and their potential for DC-mediated tumor vaccination in the clinic. These findings go beyond cancer research and may be of relevance for other disease areas that could benefit from FcγR-targeted antigen delivery, such as autoimmunity and infectious diseases.


Cancers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 3596
Author(s):  
Reza Bayat Mokhtari ◽  
Manpreet Sambi ◽  
Bessi Qorri ◽  
Narges Baluch ◽  
Neda Ashayeri ◽  
...  

Cancer immunotherapy harnesses the immune system by targeting tumor cells that express antigens recognized by immune system cells, thus leading to tumor rejection. These tumor-associated antigens include tumor-specific shared antigens, differentiation antigens, protein products of mutated genes and rearrangements unique to tumor cells, overexpressed tissue-specific antigens, and exogenous viral proteins. However, the development of effective therapeutic approaches has proven difficult, mainly because these tumor antigens are shielded, and cells primarily express self-derived antigens. Despite innovative and notable advances in immunotherapy, challenges associated with variable patient response rates and efficacy on select tumors minimize the overall effectiveness of immunotherapy. Variations observed in response rates to immunotherapy are due to multiple factors, including adaptative resistance, competency, and a diversity of individual immune systems, including cancer stem cells in the tumor microenvironment, composition of the gut microbiota, and broad limitations of current immunotherapeutic approaches. New approaches are positioned to improve the immune response and increase the efficacy of immunotherapies, highlighting the challenges that the current global COVID-19 pandemic places on the present state of immunotherapy.


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