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Order Rowavirales
Published in Paul Pumpens, Peter Pushko, Philippe Le Mercier, Virus-Like Particles, 2022
Paul Pumpens, Peter Pushko, Philippe Le Mercier
Shiratsuchi et al. (2010) constructed an adenovirus-based malaria vaccine by inserting a B cell epitope derived from a Plasmodium yoelii circumsporozoite (CS) protein into the hypervariable regions within a recombinant adenovirus expressing both P. yoelii CS protein and GFP as transgenes.
Antiprotozoal Effects of Wild Plants
Published in Mahendra Rai, Shandesh Bhattarai, Chistiane M. Feitosa, Ethnopharmacology of Wild Plants, 2021
Muhammad Subbayyal Akram, Rao Zahid Abbas, José L. Martinez
Artemisinin tackles Plasmodium spp. by oxygen free radical as it is lacking an endoperoxide bridge. The results of the in vivo trial of artemisinin give 98.6% inhibition of Plasmodium yoelii (Klayman 1985, Brossi et al. 1988).
Use of Artemisia annua L. in the Treatment of Diseases—An Update
Published in Tariq Aftab, M. Naeem, M. Masroor, A. Khan, Artemisia annua, 2017
M. Naeem, Tariq Aftab, Asfia Shabbir, M. Masroor, A. Khan
Artemisinin, a compound extracted from Artemisia , is of great importance for its different therapeutic and antimalarial activities (Kiani et al., 2016). Artemisinin and its derivatives exert their effect by interfering with the plasmodial hemoglobin catabolic pathway and inhibition of heme polymerization. In vitro experimental study shows the inhibition of digestive vacuole proteolytic activity in the malaria parasite by artemisinin (Ferreira, 2004). Ex vivo experiments have also shown accumulation of hemoglobin in the parasites treated with artemisinin, suggesting inhibition of hemoglobin degradation. Artemisinin was found to be a potent inhibitor of heme polymerization activity mediated by Plasmodium yoelii lysates as well as P. falciparum histidine-rich protein II (Penissi et al.,2006).
Loss of CD47 alters CD8+ T cell activation in vitro and immunodynamics in mice
Published in OncoImmunology, 2022
Pulak R. Nath, Dipasmita Pal-Nath, Sukhbir Kaur, Arunkumar Gangaplara, Thomas J. Meyer, Margaret C Cam, David D. Roberts
CD47 can play both promotive and protective roles based on the type of infection in mice. During bacterial E. coli infection, deficiency of CD47 protected mice from LPS-induced acute lung injury and pneumonia.62Cd47−/− mice had reduced parasitemia following infection with Plasmodium yoelii malaria parasites and enhanced survival compared to WT mice, which was attributed to enhanced phagocytosis of infected red blood cells (RBCs).63,64 In an influenza vaccine study, CD47-deficient mice responded to vaccination with increased titers of virus-specific antibodies and were better protected than WT mice.65 The protection mechanism against the viral infection was attributed solely to virus-specific antibodies.65 However, chronic LCMV-infected mice exhibit a severe defect in Fcγ-receptor (FcγR)-mediated antibody effector function.66 Therefore, similar IgG-mediated protection to LCMV infection is not anticipated in Cd47−/− mice. Candida albicans fungal infection, on the other hand, showed increased morbidity and mortality of Cd47−/− mice due to wider dissemination of infection along with elevated neutrophil, macrophage and CD4 + T cell infiltrates, and increased inflammatory cytokine levels.67 Treatment of mice infected with Ebola virus with the function blocking CD47 miap301 adversely affected survival with increased inflammatory cytokine responses, B cell activation, and CTLA4+ CD8+ and CD4 + T cells.
Thirty years of recombinant BCG: new trends for a centenary vaccine
Published in Expert Review of Vaccines, 2021
Lazaro M Marques-Neto, Zuzanna Piwowarska, Alex I. Kanno, Luana Moraes, Monalisa M Trentini, Dunia Rodriguez, Jose L. S. C. Silva, Luciana C. C. Leite
rBCG has also been used as an approach for vaccine development against parasitic pathogens due to potential induction of both humoral and cellular immune responses, which are considered to have an important role in protection against parasites. Especially for malaria, in which the plasmodium parasite is susceptible to antibodies and soluble immune molecules during traversal infection and prior to host cell invasion, and to cytotoxic T cells and activated cells of the innate and adaptive immune system when intracellular, all of which can be induced by the rBCG platform (Supplementary Table V). An rBCG strain expressing the erythrocytic stage antigen, MSP-115 (in fusion with the M. kansasii α-antigen), induced long-term protection against a Plasmodium yoelii challenge in mice [79]. Moreover, the rBCG strain expressing CSP, a pre-erythrocytic stage antigen of P. falciparum, was immunogenic in mice [80] but induced limited protection against challenge. The fusion of epitopes/proteins from multiple stages of infection has also been explored, showing induction of high levels of humoral and cellular immune responses (Supplementary Table V). The importance of mycobacterial viability was also demonstrated: rBCG expressing MSA-2 from P. falciparum induced high levels of specific antibodies and cellular responses (IFN-γ and IL-2), contrary to heat-killed rBCG-MSA-2 [81].
Can Plasmodium’s tricks for enhancing its transmission be turned against the parasite? New hopes for vector control
Published in Pathogens and Global Health, 2019
S. Noushin Emami, Melika Hajkazemian, Raimondas Mozūraitis
Parasite development in the mosquito can also affect mosquito behavior. Mosquitoes are more avid to bite a host when malaria parasites have developed into transmissible sporozoites in the salivary glands. Laboratory evidence showed that feeding persistence of female An. stephensi mosquitoes depends on the presence and development stage of the parasite (Plasmodium yoelii nigeriensis). In 10-min trials, it was shown that 33% of uninfected, 53% of those harboring oocysts and only 20% of those infected with sporozoite mosquitoes, respectively, gave up feeding on human host [72]. It seems that the feeding behavior of mosquitoes is not only mediated by the presence of parasite but also it is sensitive to the developmental stage of parasite. Mosquito are more eager to bite the host when malaria parasite has developed into transmissible sporozoites. Also, field study showed that sporozoite-infected mosquitoes took larger blood meals than uninfected mosquitoes and 82% of infected mosquitoes had engorged fully. In addition, individual mosquitoes carrying sporozoite were more likely to bite several people per night [73]. Mosquitoes infected with sporozoites of Plasmodium gallinaceum needed a larger blood meal to inhibit host-seeking behavior than those not infected [74]. For example, An. gambiae and Anopheles punctulatus infected by P. falciparum and P. vivax at sporozoite stage attempted to take more blood meals than uninfected mosquitoes, a behavior which could increase the rate of parasite transmission by increasing their biting rate [17,73].