Dormancy enables relapsing malaria parasites, such as Plasmodium vivax and cynomolgi, to survive unfavorable conditions. It is enabled by hypnozoites, parasites remaining quiescent inside hepatocytes before reactivating and establishing blood-stage infection. We integrate omics approaches to explore gene-regulatory mechanisms underlying hypnozoite dormancy.
View Article and Find Full Text PDFVaccine development for Plasmodium vivax, an important human relapsing malaria, is lagging behind. In the case of the most deadly human malaria P. falciparum, unprecedented high levels of protection have been obtained by immunization with live sporozoites under accompanying chemoprophylaxis, which prevents the onset of blood-stage malaria.
View Article and Find Full Text PDFHypnozoites are dormant liver-stage parasites unique to relapsing malarial species, including the important human pathogen , and pose a barrier to the elimination of malaria. Little is known regarding the biology of these stages, largely due to their inaccessible location. Hypnozoites can be cultured but these cultures always consist of a mixture of hepatocytes, developing forms, and hypnozoites.
View Article and Find Full Text PDFTo fight tuberculosis, better vaccination strategies are needed. Live attenuated -derived vaccine, MTBVAC, is a promising candidate in the pipeline, proven to be safe and immunogenic in humans so far. Independent studies have shown that pulmonary mucosal delivery of Bacillus Calmette-Guérin (BCG), the only tuberculosis (TB) vaccine available today, confers superior protection over standard intradermal immunization.
View Article and Find Full Text PDFBCG vaccination can strengthen protection against pathogens through the induction of epigenetic and metabolic reprogramming of innate immune cells, a process called trained immunity. We and others recently demonstrated that mucosal or intravenous BCG better protects rhesus macaques from infection and TB disease than standard intradermal vaccination, correlating with local adaptive immune signatures. In line with prior mouse data, here, we show in rhesus macaques that intravenous BCG enhances innate cytokine production associated with changes in H3K27 acetylation typical of trained immunity.
View Article and Find Full Text PDFTuberculosis (TB) still is the principal cause of death from infectious disease and improved vaccination strategies are required to reduce the disease burden and break TB transmission. Here, we investigated different routes of administration of vectored subunit vaccines based on chimpanzee-derived adenovirus serotype-3 (ChAd3) for homologous prime-boosting and modified vaccinia virus Ankara (MVA) for heterologous boosting with both vaccine vectors expressing the same antigens from (Ag85B, ESAT6, Rv2626, Rv1733, RpfD). Prime-boost strategies were evaluated for immunogenicity and protective efficacy in highly susceptible rhesus macaques.
View Article and Find Full Text PDFWhile tuberculosis continues to afflict mankind, the immunological mechanisms underlying TB disease development are still incompletely understood. Advanced preclinical models for TB research include both rhesus and cynomolgus macaques ( and , respectively), with rhesus typically being more susceptible to acute progressive TB disease than cynomolgus macaques. To determine which immune mechanisms are responsible for this dissimilar disease development, we profiled a broad range of innate and adaptive responses, both local and peripheral, following experimental pulmonary () infection of both species.
View Article and Find Full Text PDFTuberculosis (TB) remains the deadliest infectious disease, and the widely used Bacillus Calmette-Guérin (BCG) vaccine fails to curb the epidemic. An improved vaccination strategy could provide a cost-effective intervention to break the transmission cycle and prevent antimicrobial resistance. Limited knowledge of the host responses critically involved in protective immunity hampers the development of improved TB vaccination regimens.
View Article and Find Full Text PDFRelapses of dormant liver hypnozoites compromise malaria eradication efforts. New radical cure drugs are urgently needed, yet the vast gap in knowledge of hypnozoite biology impedes drug discovery. We previously unraveled the transcriptome of 6 to 7 day-old liver stages, highlighting pathways associated with hypnozoite dormancy (Voorberg-van der Wel et al.
View Article and Find Full Text PDFliver hypnozoites, which cause disease relapse, are widely considered to be the last barrier towards malaria eradication. The biology of this quiescent form of the parasite is poorly understood which hinders drug discovery. We report a comparative transcriptomic dataset of replicating liver schizonts and dormant hypnozoites of the relapsing parasite .
View Article and Find Full Text PDFIn this study we determined the mechanical output of common marmosets (Callithrix jacchus) during jumping. Vertical ground reaction forces were measured in 18 animals while they jumped from an instrumented crossbar to a crossbar located 70 cm higher. From the vertical force time histories, we calculated the rate of change of mechanical energy of the centre of mass (dE/dt).
View Article and Find Full Text PDFJ Neuroimmune Pharmacol
December 2013
The experimental autoimmune encephalitis (EAE) model is used for preclinical research into the pathogenesis of multiple sclerosis (MS), mostly in inbred, specific pathogen free (SPF)-raised laboratory mice. However, the naive state of the laboratory mouse immune system is considered a major hurdle in the translation of principles from the EAE model to the MS patient. Non-human primates (NHP) have an immune system harboring T- and B-cell memory against environmental antigens, similar as in humans.
View Article and Find Full Text PDFThe immune system is characterized by the preferential migration of lymphocytes through specific tissues (i.e., tissue tropism).
View Article and Find Full Text PDF