Live Attenuated Measles Virus Vaccine Expressing Helicobacter pylori Heat Shock Protein A

Oncolytic virus-based combination therapy in breast cancer

Breast cancer continues to pose significant challenges in the field of oncology, necessitating innovative treatment approaches. Among these, oncolytic viruses have emerged as a promising frontier in the battle against various types of cancer, including breast cancer. These viruses, often genetically modified, have the unique ability to selectively infect and destroy cancer cells while leaving healthy cells unharmed. Their efficacy in tumor eradication is not only owing to direct cell lysis but also relies on their capacity to activate the immune system, thereby eliciting a potent and sustained antitumor response. While oncolytic viruses represent a significant advancement in cancer treatment, the complexity and adaptability inherent to cancer require a diverse array of therapies. The concept of combining oncolytic viruses with other treatment modalities, such as chemotherapy, immunotherapy, and targeted therapies, has received significant attention. This synergistic approach capitalizes on the strengths of each therapy, thus creating a comprehensive strategy to tackle the heterogeneous and evolving nature of breast cancer. The purpose of this review is to provide an in-depth discussion of preclinical and clinical viro-based combination therapy in the context of breast cancer.

How Long Will It Take to Launch an Effective Helicobacter pylori Vaccine for Humans?

Helicobacter pylori infection often occurs in early childhood, and can last a lifetime if not treated with medication. H. pylori infection can also cause a variety of stomach diseases, which can only be treated with a combination of antibiotics. Combinations of antibiotics can cure H. pylori infection, but it is easy to relapse and develop drug resistance. Therefore, a vaccine is a promising strategy for prevention and therapy for the infection of H. pylori. After decades of research and development, there has been no appearance of any H. pylori vaccine reaching the market, unfortunately. This review summarizes the aspects of candidate antigens, immunoadjuvants, and delivery systems in the long journey of H. pylori vaccine research, and also introduces some clinical trials that have displayed encouraging or depressing results. Possible reasons for the inability of an H. pylori vaccine to be available over the counter are cautiously discussed and some propositions for the future of H. pylori vaccines are outlined.

Perspectives from recent advances of Helicobacter pylori vaccines research

BACKGROUND

Helicobacter pylori (H. pylori) infection is the main factor leading to some gastric diseases. Currently, H. pylori infection is primarily treated with antibiotics. However, with the widespread application of antibiotics, H. pylori resistance to antibiotics has also gradually increased year by year. Vaccines may be an alternative solution to clear H. pylori.

AIMS

By reviewing the recent progress on H. pylori vaccines, we expected it to lead to more research efforts to accelerate breakthroughs in this field.

MATERIALS & METHODS

We searched the research on H. pylori vaccine in recent years through PubMed®, and then classified and summarized these studies.

RESULTS

The study of the pathogenic mechanism of H. pylori has led to the development of vaccines using some antigens, such as urease, catalase, and heat shock protein (Hsp). Based on these antigens, whole-cell, subunit, nucleic acid, vector, and H. pylori exosome vaccines have been tested.

DISCUSSION

At present, researchers have developed many types of vaccines, such as whole cell vaccines, subunit vaccines, vector vaccines, etc. However, although some of these vaccines induced protective immunity in mouse models, only a few were able to move into human trials. We propose that mRNA vaccine may play an important role in preventing or treating H. pylori infection. The current study shows that we have developed various types of vaccines based on the virulence factors of H. pylori. However, only a few vaccines have entered human clinical trials. In order to improve the efficacy of vaccines, it is necessary to enhance T-cell immunity.

CONCLUSION

We should fully understand the pathogenic mechanism of H. pylori and find its core antigen as a vaccine target.

Versatility of live-attenuated measles viruses as platform technology for recombinant vaccines

Live-attenuated measles virus (MeV) has been extraordinarily effective in preventing measles infections and their often deadly sequelae, accompanied by remarkable safety and stability since their first licensing in 1963. The advent of recombinant DNA technologies, combined with systems to generate infectious negative-strand RNA viruses on the basis of viral genomes encoded on plasmid DNA in the 1990s, paved the way to generate recombinant, vaccine strain-derived MeVs. These live-attenuated vaccine constructs can encode and express additional foreign antigens during transient virus replication following immunization. Effective humoral and cellular immune responses are induced not only against the MeV vector, but also against the foreign antigen cargo in immunized individuals, which can protect against the associated pathogen. This review aims to present an overview of the versatility of this vaccine vector as platform technology to target various diseases, as well as current research and developmental stages, with one vaccine candidate ready to enter phase III clinical trials to gain marketing authorization, MV-CHIK.

Effect of Helicobacter pylori on immunotherapy is gaining more attention

BACKGROUND

Immunotherapy, especially immune checkpoint inhibitors, has been widely used in tumor therapy and have shown ideal clinical efficacy. However, some cancers still do not respond to PD-1/PD-L1 blockade therapy effectively. Helicobacter pylori infection might affect the curative effect of immunotherapy while it is rarely reported. We aimed to visualize the research hotspots and trends of H. pylori and immunotherapy using a bibliometric analysis to help understand the future development of basic and clinical research.

METHODS

The relevant publications on H. pylori and immunotherapy were searched on April 20, 2022, in the Web of Science Core Collection Database (WOSCC). The document types were limited to articles and reviews. The VOSviewer 1.6.16 software was used to assess the co-authorship, co-occurrence, citation of countries, institutions, authors, journals, and hotspot keywords. The research status and trend change of H. pylori and immunotherapy were analyzed by bibliometric analysis.

RESULTS

A total of 95 studies authored by 561 researchers were eventually included in this study. The majority of the retrieved studies were 55 (58%) original research articles. China conducted the greatest number of studies, followed by USA and Italy. The related topics included the following three aspects: the relationship between microorganisms and cancer, the relationship between gastric cancer and immunity, and the relationship between H. pylori and immunotherapy, including purified/cloned components of H. pylori acting as efficient adjuvant to boost tumor responses and H. pylori infection which modulate host immune responses and impact on the efficacy of antitumor immunity initiated by immune checkpoint inhibitors. The timing diagram revealed that the current research hotspots focused on effects of microorganisms on immunotherapy.

CONCLUSION

The effect of H. pylori on cancer immunotherapy is getting more and more attention in these years. It still remains uncertain, and more studies are needed in the future.

Identification of B-Cell Epitopes of HspA from Helicobacter pylori and Detection of Epitope Antibody Profiles in Naturally Infected Persons

Helicobacter pylori (H. pylori), heat-shock protein A (HspA), is a bacterial heat-shock chaperone that serves as a nickel ion scavenging protein. Ni²⁺ is an important co-factor required for the maturation and enzymatic activity of H. pylori urease and [NiFe] hydrogenase, both of which are key virulence factors for pathogen survival and colonization. HspA is an important target molecule for the diagnosis, treatment, and immune prevention of H. pylori. In this work, HspA was truncated into five fragments to determine the location of an antigen immunodominant peptide. A series of overlapping, truncated 11-amino-acid peptides in immunodominant peptide fragments were synthesized chemically and screened by ELISA. The immunogenicity and antigenicity of the screened epitope peptides were verified by ELISA, Western blot, and lymphocyte proliferation tests. Two novel B-cell epitopes were identified, covering amino acids 2–31 of HspA, which are HP11 (2–12; KFQPLGERVLV) and HP19 (18–28; ENKTSSGIIIP). The antiserum obtained from HP11-KLH and HP19-KLH immunized mice can bind to naive HspA in H. pylori SS2000, rHspA expressed in E. coli, and the corresponding GST fusion peptide. Among HspA seropositive persons, the seropositive rates of HP11 and HP19 were 21.4% and 33.3%, respectively. Both of the B-cell epitopes of HspA are highly conserved epitopes with good antigenicity and immunogenicity.