Project description:Ticks, as obligate blood-feeding arthropod vectors of pathogenic viruses, bacteria, protozoa and helminths, are responsible for prevalent tick-borne diseases (TBDs) worldwide. This arthropod constitutes the second most common that transmit pathogens among humans, after mosquitoes, and the first vector in domestic animals. Vaccines constitute the safest and more effective approach to control tick and TBDs, but this is in constant research to identify new antigens and improve vaccines formulations. The tick antigen Subolesin is a well-known vaccine protective antigen with a highly conserved sequence at both gene and protein levels in the Ixodidae and among arthropods and vertebrates. In this study, RNAseq and proteomic analyses were carried out in wild type and Subolesin knockdown tick ISE6 cells in order to identify and characterize the functional implications of Subolesin in tick cells, demonstrating once again the importance of this antigen in vaccine development against tick and TBDs.
Project description:Ticks are blood feeding arthropod ectoparasites that transmit pathogens, which cause diseases in humans and animals worldwide. In the past ten decades, the continuous human exploitation of environmental resources and the increase in human outdoor activities has promoted contact with arthropod vectors normally present in the wild, resulting in increased transmission of vector-borne pathogens. In addition, vector populations are expanding in response to climate change and human interventions that impact reservoir host movement and human exposure to infected vectors. Among these emerging vector-borne pathogens, Anaplasma phagocytophilum (Rickettsiales: Anaplasmataceae) has become an important tick-borne pathogen in the United States, Europe and Asia, with increasing numbers of infected people and animals every year. Diseases caused by A. phagocytophilum include human granulocytic anaplasmosis (HGA), equine and canine granulocytic anaplasmosis and tick-borne fever (TBF) in ruminants. The natural infection cycle of A. phagocytophilum is dependent upon the presence of infected vertebrate reservoir hosts and Ixodid tick vectors. In the United States and Europe the main vector species are Ixodes scapularis, Ixodes pacificus, and Ixodes ricinus, while a wide range of mammals, lizards, and birds serve as reservoir hosts for various A. phagocytophilum genotypes. A. phagocytophilum initially infects tick midgut cells and then subsequently develops in salivary glands for transmission to susceptible hosts during tick feeding where the pathogen infects granulocytic cells, primarily neutrophils. Anaplasma phagocytophilum develops within membrane-bound inclusions in the host cell cytoplasm. This pathogen has evolved with its tick and vertebrate hosts through dynamic processes involving genetic traits of the pathogen and hosts that collectively mediate pathogen infection, development, persistence, and survival. However, the mechanisms used by A. phagocytophilum for molecular mechanisms involved in tick-pathogen interactions have not been fully characterized. The objective of this study is to characterize the dynamics of the microRNA response in the tick vector Ixodes scapularis in response to A. phagocytophilum infection. To address this objective, the composition of tick microRNAs was characterize using RNA sequencing in I. scapularis tick cells in response to A. phagocytophilum infection. The discovery of these mechanisms provides evidence that a control strategy could be developed targeted at both vertebrate and tick hosts for more complete control of A. phagocytophilum and its associated diseases.
Project description:Anaplasma phagocytophilum is an emerging zoonotic pathogen that causes human granulocytic anaplasmosis. These intracellular bacteria establish infection by affecting cell function in both the vertebrate host and the tick vector, Ixodes scapularis. Previous studies have characterized the tick transcriptome and proteome in response to A. phagocytophilum infection. However, in the post-genomic era, the integration of omics datasets through a systems biology approach allows network-based analyses to describe the complexity and functionality of biological systems such as host-pathogen interactions and the discovery of new targets for prevention and control of infectious diseases. This study reports for the first time a systems biology integration of metabolomics, transcriptomics and proteomics data to characterize essential metabolic pathways involved in the response of tick cells to A. phagocytophilum infection. The results showed that infection affected protein processing in endoplasmic reticulum and glucose metabolic pathways in tick cells. These results supported tick-Anaplasma co-evolution by providing new evidence of how tick cells limit pathogen infection, while the pathogen benefits from the tick cell response to establish infection. The results suggested that A. phagocytophilum induces protein misfolding to limit the tick cell response and facilitate infection, but requires protein degradation to prevent ER stress and cell apoptosis to survive in infected cells. Additionally, A. phagocytophilum may benefit from the tick cell’s ability to limit bacterial infection through PEPCK inhibition leading to decreased glucose metabolism, which also results in the inhibition of cell apoptosis that increases infection of tick cells. These results support the use of this experimental approach to systematically identify tick cell pathways and molecular mechanisms involved in tick-pathogen interactions
Project description:Anaplasma phagocytophilum is an emerging zoonotic pathogen that causes human granulocytic anaplasmosis. These intracellular bacteria establish infection by affecting cell function in both the vertebrate host and the tick vector, Ixodes scapularis. Previous studies have characterized the tick transcriptome and proteome in response to A. phagocytophilum infection. However, in the post-genomic era, the integration of omics datasets through a systems biology approach allows network-based analyses to describe the complexity and functionality of biological systems such as host-pathogen interactions and the discovery of new targets for prevention and control of infectious diseases. This study reports for the first time a systems biology integration of metabolomics, transcriptomics and proteomics data to characterize essential metabolic pathways involved in the response of tick cells to A. phagocytophilum infection. The results showed that infection affected protein processing in endoplasmic reticulum and glucose metabolic pathways in tick cells. These results supported tick-Anaplasma co-evolution by providing new evidence of how tick cells limit pathogen infection, while the pathogen benefits from the tick cell response to establish infection. The results suggested that A. phagocytophilum induces protein misfolding to limit the tick cell response and facilitate infection, but requires protein degradation to prevent ER stress and cell apoptosis to survive in infected cells. Additionally, A. phagocytophilum may benefit from the tick cellâs ability to limit bacterial infection through PEPCK inhibition leading to decreased glucose metabolism, which also results in the inhibition of cell apoptosis that increases infection of tick cells. These results support the use of this experimental approach to systematically identify tick cell pathways and molecular mechanisms involved in tick-pathogen interactions Two samples with two replicates each were analyzed. Samples included Ixodes scapularis ISE6 cells uninfected (control) and infected with Anaplasma phagocytophilum human NY18 isolate.
Project description:Babesia parasites transition between a mammalian host, where they cause babesiosis, and the tick vector that transmits them. This transition provides an environmental signal resulting in altered gene expression allowing the completion of the parasite’s life cycle. A comparison of the different life stages that occur within mammalian and tick hosts can provide insight into the adaptation of Babesia to these different environments. In this study, we used RNA-Seq to compare gene expression between Babesia bovis blood stages and tick derived kinetes.
Project description:Tick infestations by Rhipicephalus microplus, the cattle tick, cause enormous losses to health and animal production. Ticks induce immune response in their hosts; therefore their immunobiological control is feasible. The available anti-tick vaccines display variable efficacy and short-lived, encouraging the search for new protective antigens. The identification of important genes in tick parasitism may indicate protective antigens useful to compose an anti-tick vaccine. We have developed and tested so far four recombinant salivary antigens as a multicomponent anti-tick vaccine in tick-susceptible bovines (Holstein breed). The challenge with R. microplus larvae displayed that tick infestation in vaccinated bovines was significantly reduced. In order to elucidate the molecular mechanisms trigged after immunisation and during infestation, RNA-seq data of peripheral blood from vaccinated and control animals were obtained in different periods of the immunisation trial. A total of 24 mRNA-seq Illumina libraries (single-end, 100 bp) were analysed to identify differential gene expression according to the experimental condition.
Project description:This experiment was undertaken to document changes in gene expression in the skin of tick-resistant Brahman (Bos indicus) and tick-susceptible Holstein-Friesian (Bos taurus) cattle prior to, and following, infestation with the cattle tick Rhipicephalus (Boophilus) microplus Experiment Overall Design: RNA was extracted from skin samples of tick-naïve cattle (animals with no previous R.microplus exposure) and tick-infested cattle after a period of successive, heavy infestations with R. microplus. Skin samples taken from tick-infested animals were taken at sites where tick larvae (approximately 24 h old) were attached to the skin sample. Skin samples were of 8 mm diameter and full skin thickness (approximately 10 mm). RNA samples from 12 animals (3 tick-naive Holstein-Friesian, 3 tick-naive Brahman, 3 tick-infested Holstein-Friesian and 3 tick-infested Brahman) were processed and hybridised to individual slides.
Project description:Anaplasma phagocytophilum is an emerging zoonotic pathogen that causes human granulocytic anaplasmosis. These intracellular bacteria establish infection by affecting cell function in both the vertebrate host and the tick vector, Ixodes scapularis. Previous studies have characterized the tick transcriptome and proteome in response to A. phagocytophilum infection. However, in the post-genomic era, the integration of omics datasets through a systems biology approach allows network-based analyses to describe the complexity and functionality of biological systems such as host-pathogen interactions and the discovery of new targets for prevention and control of infectious diseases. This study reports for the first time a systems biology integration of metabolomics, transcriptomics and proteomics data to characterize essential metabolic pathways involved in the response of tick cells to A. phagocytophilum infection. The results showed that infection affected protein processing in endoplasmic reticulum and glucose metabolic pathways in tick cells. These results supported tick-Anaplasma co-evolution by providing new evidence of how tick cells limit pathogen infection, while the pathogen benefits from the tick cell response to establish infection. The results suggested that A. phagocytophilum induces protein misfolding to limit the tick cell response and facilitate infection, but requires protein degradation to prevent ER stress and cell apoptosis to survive in infected cells. Additionally, A. phagocytophilum may benefit from the tick cell’s ability to limit bacterial infection through PEPCK inhibition leading to decreased glucose metabolism, which also results in the inhibition of cell apoptosis that increases infection of tick cells. These results support the use of this experimental approach to systematically identify tick cell pathways and molecular mechanisms involved in tick-pathogen interactions.
Project description:There has been an emergence and expansion of tick-borne diseases in Europe, Asia and North America in recent years, including Lyme disease, tick-borne encephalitis, and human anaplasmosis. The primary tick vectors implicated are hard ticks of the Ixodes genera. Although much is known about the host response to these bacterial and viral pathogens, there is limited knowledge of the cellular responses to infection within the tick vector. The bacterium Anaplasma phagocytophilum (A. phagocytophilum), is able to bypass apoptotic processes in ticks, enabling infection to proceed. However, the tick cellular responses to infection with the flaviviruses tick-borne encephalitis virus (TBEV) and louping ill virus (LIV), which cause tick-borne encephalitis and louping ill respectively, are less clear. Infection of an Ixodes ricinus (I. ricinus) tick cell line with the viruses LIV and TBEV, and the bacterium A. phagocytophilum, identified activation of common and distinct cellular pathways. In particular, commonly-upregulated genes included those that modulate apoptotic pathways (HSP70), putative anti-pathogen genes (FKBP and XBL1), and genes that influence the tick innate immune response, including selective activation of toll genes. These data provide an insight into potentially key genes involved in the tick cellular response to viral or bacterial infection.