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Expert Review of Vaccines Nov 2021Pathogenesis of Chagas disease (CD) caused by involves chronic oxidative and inflammatory stress. In this review, we discuss the research efforts in therapeutic vaccine... (Review)
Review
INTRODUCTION
Pathogenesis of Chagas disease (CD) caused by involves chronic oxidative and inflammatory stress. In this review, we discuss the research efforts in therapeutic vaccine development to date and the potential challenges imposed by oxidative stress in achieving an efficient therapeutic vaccine against CD.
AREAS COVERED
This review covers the immune and nonimmune mechanisms of reactive oxygen species production and immune response patterns during in CD. A discussion on immunotherapy development efforts, the efficacy of antigen-based immune therapies against , and the role of antioxidants as adjuvants is discussed to provide promising insights to developing future treatment strategies against CD.
EXPERT OPINION
Administration of therapeutic vaccines can be a good option to confront persistent parasitemia in CD by achieving a rapid, short-lived stimulation of type 1 cell-mediated immunity. At the same time, adjunct therapies could play a critical role in the preservation of mitochondrial metabolism and cardiac muscle contractility in CD. We propose combined therapy with antigen-based vaccine and small molecules to control the pathological oxidative insult would be effective in the conservation of cardiac structure and function in CD.
Topics: Chagas Disease; Humans; Oxidative Stress; Protozoan Vaccines; Trypanosoma cruzi; Vaccine Development
PubMed: 34406892
DOI: 10.1080/14760584.2021.1969230 -
Expert Review of Vaccines May 2015Chagas disease is a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi. This illness is now becoming global, mainly due to congenital... (Review)
Review
Chagas disease is a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi. This illness is now becoming global, mainly due to congenital transmission, and so far, there are no prophylactic or therapeutic vaccines available to either prevent or treat Chagas disease. Therefore, different approaches aimed at identifying new protective immunogens are urgently needed. Live vaccines are likely to be more efficient in inducing protection, but safety issues linked with their use have been raised. The development of improved protozoan genetic manipulation tools and genomic and biological information has helped to increase the safety of live vaccines. These advances have generated a renewed interest in the use of genetically attenuated parasites as vaccines against Chagas disease. This review discusses the protective capacity of genetically attenuated parasite vaccines and the challenges and perspectives for the development of an effective whole-parasite Chagas disease vaccine.
Topics: Chagas Disease; Drug Discovery; Gene Deletion; Humans; Protozoan Vaccines; Trypanosoma cruzi; Vaccines, Attenuated
PubMed: 25496192
DOI: 10.1586/14760584.2015.989989 -
Frontiers in Immunology 2023, a specialized intracellular parasite, causes a widespread zoonotic disease and is a severe threat to social and economic development. There is a lack of effective...
, a specialized intracellular parasite, causes a widespread zoonotic disease and is a severe threat to social and economic development. There is a lack of effective drugs and vaccines against infection. Recently, mRNA vaccines have been rapidly developed, and their packaging materials and technologies are well established. In this study, TGGT1_216200 (TG_200), a novel molecule from , was identified using bioinformatic screening analysis. TG_200 was purified and encapsulated with a lipid nanoparticle (LNP) to produce the TG_200 mRNA-LNP vaccine. The immune protection provided by the new vaccine and its mechanisms after immunizing BABL/C mice intramuscular injection were investigated. There was a strong immune response when mice were vaccinated with TG_200 mRNA-LNP. Elevated levels of anti--specific immunoglobulin G (IgG), and a higher IgG2a-to-IgG1 ratio was observed. The levels of interleukin-12 (IL-12), interferon-γ (IFN-γ), IL-4, and IL-10 were also elevated. The result showed that the vaccine induced a mixture of Th1 and Th2 cells, and Th1-dominated humoral immune response. Significantly increased antigen-specific splenocyte proliferation was induced by TG_200 mRNA-LNP immunization. The vaccine could also induce -specific cytotoxic T lymphocytes (CTLs). The expression levels of interferon regulatory factor 8 (IRF8), T-Box 21 (T-bet), and nuclear factor kappa B (NF-κB) were significantly elevated after TG_200 mRNA-LNP immunization. The levels of CD83, CD86, MHC-I, MHC-II, CD8, and CD4 molecules were also higher. The results indicated that TG_200 mRNA-LNP produced specific cellular and humoral immune responses. Most importantly, TG_200 mRNA-LNP immunized mice survived significantly longer (19.27 ± 3.438 days) than the control mice, which died within eight days after challenge ( 0.001). The protective effect of adoptive transfer was also assessed, and mice receiving serum and splenocytes from mice immunized with TG_200 mRNA-LNP showed improved survival rates of 9.70 ± 1.64 days and, 13.40 ± 2.32 days, respectively ( 0.001). The results suggested that TG_200 mRNA-LNP is a safe and promising vaccine against infection.
Topics: Animals; Mice; Mice, Inbred BALB C; Protozoan Proteins; Protozoan Vaccines; Toxoplasmosis; Immunization; Immunoglobulin G
PubMed: 37122740
DOI: 10.3389/fimmu.2023.1161507 -
Immunotherapy Feb 2016
Topics: Animals; Chagas Disease; Humans; Portraits as Topic; Protozoan Vaccines; Trypanosoma cruzi
PubMed: 26787323
DOI: 10.2217/imt.15.115 -
Tropical Animal Health and Production Jan 2016Trichomonas vaginalis and Tritrichomonas foetus are important extracellular protozoans that cause, respectively, human and bovine venereal diseases. Trichomonads are... (Review)
Review
Trichomonas vaginalis and Tritrichomonas foetus are important extracellular protozoans that cause, respectively, human and bovine venereal diseases. Trichomonads are extracellular parasites that primarily inhabit the genital tracts of the mammalian hosts where they overcome the mucus barrier and parasitize mucosa by contact-dependent or contact-independent cytotoxicity. Transient immunity is usually achieved by the host after clinical infection. At present, vaccination in cattle reduces infection rates and reproductive wastage in affected herds. After vaccination, immunoglobulin G (IgG) levels increase in systemic circulation while immunoglobulin A (IgA) levels rise in the vagina. Only moderate protection is conferred by means of vaccination. Future vaccine development strategies are needed for cattle to enhance the antigenic component or use adjuvant that strongly activates the innate immune response to produce safe and potent vaccines. This paper reviews the current knowledge of the immunology of trichomoniasis infection and the challenges and potential of vaccines in the control of the infection in human and bovine trichomoniasis.
Topics: Animals; Cattle; Cattle Diseases; Humans; Protozoan Vaccines; Trichomonas Infections; Vaccination
PubMed: 26424377
DOI: 10.1007/s11250-015-0909-1 -
Fish & Shellfish Immunology Jul 2020The aquaculture industry in Korea has grown rapidly since the 1960s, and it is a major food source. However, the expansion of aquaculture systems has increased the...
The aquaculture industry in Korea has grown rapidly since the 1960s, and it is a major food source. However, the expansion of aquaculture systems has increased the chances of infectious disease outbreaks, and vaccination plays an important role in commercial fish farming. This is the first comprehensive review of commercial fish vaccines in Korea. It not only provides an overview of commercially available fish vaccines and their associated approval processes and laws, but also some perspectives on research advances regarding fish vaccines in Korea. In Korea, fish vaccines are approved only after their safety and effectiveness have been verified according to the Pharmaceutical Affairs Act, and after approval, each vaccine lot must pass the national evaluation criteria. As of the end of 2019, 29 vaccines were approved for 10 fish pathogens, including both single and combination vaccines containing more than two inactivated pathogens. The approved fish vaccines consist of 2 immersion vaccines, as well as 1 intramuscular and 26 intraperitoneal vaccines, which require syringe injection. All the 29 vaccines are manufactured as formalin-inactivated vaccines; 1 is an adjuvant vaccine and 28 are non-adjuvant vaccines; 25 are bacterial vaccines, 2 are viral vaccines, 1 is a parasite vaccine, and 1 is a parasite and bacterial vaccine. In terms of the target fish species, 27 vaccines are used in the olive flounder (Paralichthys olivaceus), 1 in the starry flounder (Platichthys stellatus), and 1 in the red seabream (Pagrus major), striped beakfish (Oplegnathus fasciatus), and amberjack (Seriola quinqueradiata). This imbalance exists mostly because the olive flounder is the main farmed fish species in Korea. In 2018, 67.71 million vaccine doses were distributed following satisfactory performance in the national evaluation. They were used to vaccinate approximately 80.6% of farmed olive flounders.
Topics: Adjuvants, Immunologic; Animals; Bacterial Vaccines; Fish Diseases; Formaldehyde; Protozoan Vaccines; Republic of Korea; Vaccination; Vaccines, Inactivated; Viral Vaccines
PubMed: 32272258
DOI: 10.1016/j.fsi.2020.04.004 -
Trends in Parasitology Apr 2022Vaccine-mediated immunity to parasites has not been achieved. Immune C57BL/6 mice are susceptible to secondary Toxoplasma gondii infection. Using a forward genetics...
Vaccine-mediated immunity to parasites has not been achieved. Immune C57BL/6 mice are susceptible to secondary Toxoplasma gondii infection. Using a forward genetics approach, Souza et al. identify Nfkbid as an important factor for the regulation of B cell immunity during secondary Toxoplasma infection and protection against rechallenge.
Topics: Animals; Antibodies, Protozoan; Immunity, Cellular; Immunity, Humoral; Mice; Mice, Inbred C57BL; Protozoan Proteins; Protozoan Vaccines; Toxoplasma; Toxoplasmosis; Toxoplasmosis, Animal; Vaccines, DNA
PubMed: 35190281
DOI: 10.1016/j.pt.2022.01.010 -
Frontiers in Immunology 2019Parasites, including African trypanosomes, utilize several immune evasion strategies to ensure their survival and completion of their life cycles within their hosts. The... (Review)
Review
Parasites, including African trypanosomes, utilize several immune evasion strategies to ensure their survival and completion of their life cycles within their hosts. The defense factors activated by the host to resolve inflammation and restore homeostasis during active infection could be exploited and/or manipulated by the parasites in an attempt to ensure their survival and propagation. This often results in the parasites evading the host immune responses as well as the host sustaining some self-inflicted collateral tissue damage. During infection with African trypanosomes, both effector and suppressor cells are activated and the balance between these opposing arms of immunity determines susceptibility or resistance of infected host to the parasites. Immune evasion by the parasites could be directly related to parasite factors, (e.g., antigenic variation), or indirectly through the induction of suppressor cells following infection. Several cell types, including suppressive macrophages, myeloid-derived suppressor cells (MDSCs), and regulatory T cells have been shown to contribute to immunosuppression in African trypanosomiasis. In this review, we discuss the key factors that contribute to immunity and immunosuppression during infection, and how these factors could aid immune evasion by African trypanosomes. Understanding the regulatory mechanisms that influence resistance and/or susceptibility during African trypanosomiasis could be beneficial in designing effective vaccination and therapeutic strategies against the disease.
Topics: Animals; Humans; Immune Evasion; Macrophages; Myeloid-Derived Suppressor Cells; Protozoan Vaccines; T-Lymphocytes, Regulatory; Trypanosoma congolense; Trypanosomiasis, African
PubMed: 31824512
DOI: 10.3389/fimmu.2019.02738 -
Biochimica Et Biophysica Acta.... May 2020Chagas disease is currently endemic to 21 Latin-American countries and has also become a global concern because of globalization and mass migration of chronically... (Review)
Review
Chagas disease is currently endemic to 21 Latin-American countries and has also become a global concern because of globalization and mass migration of chronically infected individuals. Prophylactic and therapeutic vaccination might contribute to control the infection and the pathology, as complement of other strategies such as vector control and chemotherapy. Ideal prophylactic vaccine would produce sterilizing immunity; however, a reduction of the parasite burden would prevent progression from Trypanosoma cruzi infection to Chagas disease. A therapeutic vaccine for Chagas disease may improve or even replace the treatment with current drugs which have several side effects and require long term treatment that frequently leads to therapeutic withdrawal. Here, we will review some aspects about sub-unit vaccines, the rationale behind the selection of the immunogen, the role of adjuvants, the advantages and limitations of DNA-based vaccines and the idea of therapeutic vaccines. One of the main limitations to advance vaccine development against Chagas disease is the high number of variables that must be considered and the lack of uniform criteria among research laboratories. To make possible comparisons, much of this review will be focused on experiments that kept many variables constant including antigen mass/doses, type of eukaryotic plasmid, DNA-delivery system, mice strain and sex, lethal and sublethal model of infection, and similar immunogenicity and efficacy assessments.
Topics: Animals; Antigens, Protozoan; Chagas Cardiomyopathy; Disease Models, Animal; Female; Humans; Immunogenicity, Vaccine; Male; Mice; Protozoan Vaccines; Research Design; Sex Factors; Trypanosoma cruzi; Vaccines, Subunit
PubMed: 31904415
DOI: 10.1016/j.bbadis.2019.165658 -
Acta Tropica Dec 2019Trypanosoma cruzi (T. cruzi) is the causative agent for Chagas disease (CD). There is a critical lack of methods for prevention of infection or treatment of acute... (Review)
Review
Trypanosoma cruzi (T. cruzi) is the causative agent for Chagas disease (CD). There is a critical lack of methods for prevention of infection or treatment of acute infection and chronic disease. Studies in experimental models have suggested that the protective immunity against T. cruzi infection requires the elicitation of Th1 cytokines, lytic antibodies and the concerted activities of macrophages, T helper cells, and cytotoxic T lymphocytes (CTLs). In this review, we summarize the research efforts in vaccine development to date and the challenges faced in achieving an efficient prophylactic or therapeutic vaccine against human CD.
Topics: Animals; Chagas Disease; Humans; Protozoan Vaccines; Trypanosoma cruzi
PubMed: 31513763
DOI: 10.1016/j.actatropica.2019.105168