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Utpal Pal - One of the best experts on this subject based on the ideXlab platform.
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interactions between Borrelia burgdorferi and ticks
Nature Reviews Microbiology, 2020Co-Authors: Cheyne Kurokawa, Erol Fikrig, Utpal Pal, Geoffrey E Lynn, Joao H F Pedra, Sukanya NarasimhanAbstract:Borrelia burgdorferi is the causative agent of Lyme disease and is transmitted to vertebrate hosts by Ixodes spp. ticks. The spirochaete relies heavily on its arthropod host for basic metabolic functions and has developed complex interactions with ticks to successfully colonize, persist and, at the optimal time, exit the tick. For example, proteins shield spirochaetes from immune factors in the bloodmeal and facilitate the transition between vertebrate and arthropod environments. On infection, B. burgdorferi induces selected tick proteins that modulate the vector gut microbiota towards an environment that favours colonization by the spirochaete. Additionally, the recent sequencing of the Ixodes scapularis genome and characterization of tick immune defence pathways, such as the JAK-STAT, immune deficiency and cross-species interferon-γ pathways, have advanced our understanding of factors that are important for B. burgdorferi persistence in the tick. In this Review, we summarize interactions between B. burgdorferi and I. scapularis during infection, as well as interactions with tick gut and salivary gland proteins important for establishing infection and transmission to the vertebrate host.
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lyme disease spirochaete Borrelia burgdorferi does not require thiamin
Nature microbiology, 2017Co-Authors: Kai Zhang, Utpal Pal, Weigang Qiu, Jiang Bian, Yijie Deng, Alexis A Smith, Roy Nunez, Steven E EalickAbstract:Thiamin pyrophosphate (ThDP), the active form of thiamin (vitamin B1), is believed to be an essential cofactor for all living organisms1,2. Here, we report the unprecedented result that thiamin is dispensable for the growth of the Lyme disease pathogen Borrelia burgdorferi (Bb)3. Bb lacks genes for thiamin biosynthesis and transport as well as known ThDP-dependent enzymes4, and we were unable to detect thiamin or its derivatives in Bb cells. We showed that eliminating thiamin in vitro and in vivo using BcmE, an enzyme that degrades thiamin, has no impact on Bb growth and survival during its enzootic infectious cycle. Finally, high-performance liquid chromatography analysis reveals that the level of thiamin and its derivatives in Ixodes scapularis ticks, the enzootic vector of Bb, is extremely low. These results suggest that by dispensing with use of thiamin, Borrelia, and perhaps other tick-transmitted bacterial pathogens, are uniquely adapted to survive in tick vectors before transmitting to mammalian hosts. To our knowledge, such a mechanism has not been reported previously in any living organisms.
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Borrelia burgdorferi and tick proteins supporting pathogen persistence in the vector
Future Microbiology, 2013Co-Authors: Faith Kung, Juan Anguita, Utpal PalAbstract:Borrelia burgdorferi, a pathogen transmitted by Ixodes ticks, is responsible for a prevalent illness known as Lyme disease, and a vaccine for human use is unavailable. Recently, genome sequences of several B. burgdorferi strains and Ixodes scapularis ticks have been determined. In addition, remarkable progress has been made in developing molecular genetic tools to study the pathogen and vector, including their intricate relationship. These developments are helping unravel the mechanisms by which Lyme disease pathogens survive in a complex enzootic infection cycle. Notable discoveries have already contributed to understanding the spirochete gene regulation accounting for the temporal and spatial expression of B. burgdorferi genes during distinct phases of the lifecycle. A number of pathogen and vector gene products have also been identified that contribute to microbial virulence and/or persistence. These research directions will enrich our knowledge of vector-borne infections and contribute towards the dev...
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TROSPA, an Ixodes scapularis receptor for Borrelia burgdorferi
Cell, 2004Co-Authors: Utpal Pal, Nandhini Ramamoorthi, Tian Wang, Ruth R. Montgomery, Aravinda Desilva, Fukai Bao, Xiaofeng Yang, Marc Pypaert, Deepti PradhanAbstract:The Lyme disease agent Borrelia burgdorferi naturally persists in a cycle that primarily involves ticks and mammals. We have now identified a tick receptor (TROSPA) that is required for spirochetal colonization of Ixodes scapularis. B. burgdorferi outer surface protein A, which is abundantly expressed on spirochetes within the arthropod and essential for pathogen adherence to the vector, specifically bound to TROSPA. TROSPA mRNA levels in ticks increased following spirochete infestation and decreased in response to engorgement, events that are temporally linked to B. burgdorferi entry into and egress from the vector. The blockade of TROSPA by TROSPA antisera or by the repression of TROSPA expression via RNA interference reduced B. burgdorferi adherence to the I. scapularis gut in vivo, thereby preventing efficient colonization of the vector and subsequently reducing pathogen transmission to the mammalian host. Identification of an I. scapularis receptor for B. burgdorferi is the first step toward elucidating arthropod ligands that are required for survival of spirochetes in nature.
Goudarz Molaei - One of the best experts on this subject based on the ideXlab platform.
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passive tick surveillance exploring spatiotemporal associations of Borrelia burgdorferi spirochaetales spirochaetaceae babesia microti piroplasmida babesiidae and anaplasma phagocytophilum rickettsiales anaplasmataceae infection in ixodes scapularis
Vector-borne and Zoonotic Diseases, 2020Co-Authors: Eliza A H Little, Goudarz MolaeiAbstract:Ixodes scapularis transmits a group of pathogens, including Borrelia burgdorferi, Babesia microti, and Anaplasma phagocytophilum, the causative agents for Lyme disease, babesiosis, and anaplasmosis...
Erol Fikrig - One of the best experts on this subject based on the ideXlab platform.
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interactions between Borrelia burgdorferi and ticks
Nature Reviews Microbiology, 2020Co-Authors: Cheyne Kurokawa, Erol Fikrig, Utpal Pal, Geoffrey E Lynn, Joao H F Pedra, Sukanya NarasimhanAbstract:Borrelia burgdorferi is the causative agent of Lyme disease and is transmitted to vertebrate hosts by Ixodes spp. ticks. The spirochaete relies heavily on its arthropod host for basic metabolic functions and has developed complex interactions with ticks to successfully colonize, persist and, at the optimal time, exit the tick. For example, proteins shield spirochaetes from immune factors in the bloodmeal and facilitate the transition between vertebrate and arthropod environments. On infection, B. burgdorferi induces selected tick proteins that modulate the vector gut microbiota towards an environment that favours colonization by the spirochaete. Additionally, the recent sequencing of the Ixodes scapularis genome and characterization of tick immune defence pathways, such as the JAK-STAT, immune deficiency and cross-species interferon-γ pathways, have advanced our understanding of factors that are important for B. burgdorferi persistence in the tick. In this Review, we summarize interactions between B. burgdorferi and I. scapularis during infection, as well as interactions with tick gut and salivary gland proteins important for establishing infection and transmission to the vertebrate host.
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the tick salivary protein salp15 inhibits the killing of serum sensitive Borrelia burgdorferi sensu lato isolates
Infection and Immunity, 2008Co-Authors: Tim J Schuijt, Erol Fikrig, Joppe W. Hovius, Nandhini Ramamoorthi, Nathalie D Van Burgel, Alje P Van DamAbstract:Borrelia burgdorferi, the agent of Lyme disease, is transmitted by ticks. During transmission from the tick to the host, spirochetes are delivered with tick saliva, which contains the salivary protein Salp15. Salp15 has been shown to protect spirochetes against B. burgdorferi-specific antibodies. We now show that Salp15 from both Ixodes ricinus and Ixodes scapularis protects serum-sensitive isolates of Borrelia burgdorferi sensu lato against complement-mediated killing. I. ricinus Salp15 showed strong protective effects compared to those of I. scapularis Salp15. Deposition of terminal C5b to C9 (one molecule each of C5b, C6, C7, and C8 and one or more molecules of C9) complement complexes, part of the membrane attack complex, on the surface of B. burgdorferi was inhibited in the presence of Salp15. In the presence of normal human serum, serum-sensitive Borrelia burgdorferi requires protection against complement-mediated killing, which is provided, at least in part, by the binding to the tick salivary protein Salp15.
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p55 an immunogenic but nonprotective 55 kilodalton Borrelia burgdorferi protein in murine lyme disease
Infection and Immunity, 1996Co-Authors: Sunlian Feng, Stephen W Barthold, Sam R Telford, Erol FikrigAbstract:Immunization of C3H mice with P55 (previously called S1), a 55-kDa Borrelia burgdorferi antigen that is immunogenic after infection, elicited a strong antibody response but did not protect mice against B. burgdorferi challenge. Mice immunized with a P55 fusion protein in complete Freund's adjuvant developed anti-P55 antibodies, detectable at a titer of 1:10,000 by immunoblotting. To determine, if a protective response had been elicited, P55-vaccinated mice were fed upon by ticks infected with B. burgdorferi. The frequency of B. burgdorferi infection was similar in P55-immunized and control mice, and spirochetes were not destroyed within ticks that fed on P55-vaccinated mice. P55 is an immunogenic antigen that does not induce a protective response in the vertebrate or invertebrate host.
Patricia A Rosa - One of the best experts on this subject based on the ideXlab platform.
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biology of infection with Borrelia burgdorferi
Infectious Disease Clinics of North America, 2008Co-Authors: Kit Tilly, Patricia A Rosa, Philip E StewartAbstract:The spirochete Borrelia burgdorferi is a tick-borne obligate parasite whose normal reservoir is a variety of small mammals. Although infection of these natural hosts does not lead to disease, infection of humans can result in Lyme disease as a consequence of the human immunopathologic response to B burgdorferi . Consistent with the pathogenesis of Lyme disease, bacterial products that allow B burgdorferi to replicate and survive seem to be primarily what is required for the bacterium to cause disease in a susceptible host. This article describes the basic biology of B burgdorferi and reviews some of the bacterial components required for infection of and survival in the mammalian and tick hosts.
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temperature related differential expression of antigens in the lyme disease spirochete Borrelia burgdorferi
Infection and Immunity, 1995Co-Authors: Brian Stevenson, Tom G Schwan, Patricia A RosaAbstract:Previous studies have demonstrated that Borrelia burgdorferi in the midguts of infected ticks shows increased expression of the antigenic outer surface protein OspC after the ticks have ingested a blood meal. This differential expression is at least partly due to a change in temperature, as an increase in OspC levels is also observed when cultures are shifted from 23 to 35 degrees C. Immunoblotting of bacterial lysates with sera from infected mice indicated that the levels of several additional antigens were also increased in bacterial cultures shifted to 35 degrees C; we have identified one antigen as OspE. We have also observed differential expression of OspF, which has been proposed to be coexpressed in an operon with the gene encoding OspE.
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induction of an outer surface protein on Borrelia burgdorferi during tick feeding
Proceedings of the National Academy of Sciences of the United States of America, 1995Co-Authors: Tom G Schwan, Joseph Piesman, William T Golde, Marc C Dolan, Patricia A RosaAbstract:Lyme disease spirochetes, Borrelia burgdorferi sensu lato, are maintained in zoonotic cycles involving ticks and small mammals. In unfed ticks, the spirochetes produce one outer surface protein, OspA, but not OspC. During infection in mammals, immunological data suggest that the spirochetes have changed their surface, now expressing OspC but little or no OspA. We find by in vitro growth experiments that this change is regulated in part by temperature; OspC is produced by spirochetes at 32-37 degrees C but not at 24 degrees C. Furthermore, spirochetes in the midgut of ticks that have fully engorged on mice now have OspC on their surface. Thus two environmental cues, an increase in temperature and tick feeding, trigger a major alteration of the spirochetal outer membrane. This rapid synthesis of OspC by spirochetes during tick feeding may play an essential role in the capacity of these bacteria to successfully infect mammalian hosts, including humans, when transmitted by ticks.
Robert S. Lane - One of the best experts on this subject based on the ideXlab platform.
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Spatial clustering of Borrelia burgdorferi sensu lato within populations of Allen's chipmunks and dusky-footed woodrats in northwestern California
2018Co-Authors: Gregory M. Hacker, Richard N Brown, Natalia Fedorova, Yvette A. Girard, Mark Higley, Bernadette Clueit, Robert S. LaneAbstract:The ecology of Lyme borreliosis is complex in northwestern California, with several potential reservoir hosts, tick vectors, and genospecies of Borrelia burgdorferi sensu lato. The primary objective of this study was to determine the fine-scale spatial distribution of different genospecies in four rodent species, the California ground squirrel (Otospermophilus beecheyi), northern flying squirrel (Glaucomys sabrinus), dusky-footed woodrat (Neotoma fuscipes), and Allen’s chipmunk (Neotamias senex). Rodents were live-trapped between June 2004 and May 2005 at the Hoopa Valley Tribal Reservation (HVTR) in Humboldt County, California. Ear-punch biopsies obtained from each rodent were tested by polymerase chain reaction (PCR) and sequencing analysis. The programs ArcGIS and SaTScan were used to examine the spatial distribution of genospecies. Multinomial log-linear models were used to model habitat and host-specific characteristics and their effect on the presence of each Borrelial genospecies. The Akaike information criterion (AICc) was used to compare models and determine model fit. Borrelia burgdorferi sensu stricto was primarily associated with chipmunks and B. bissettiae largely with woodrats. The top model included the variables “host species”, “month”, and “elevation” (weight = 0.84). Spatial clustering of B. bissettiae was detected in the northwestern section of the HVTR, whereas B. burgdorferi sensu stricto was clustered in the southeastern section. We conclude that the spatial distribution of these Borreliae are driven at least in part by host species, time-of-year, and elevation.
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sylvatic maintenance of Borrelia burgdorferi spirochaetales in northern california untangling the web of transmission
Journal of Medical Entomology, 2006Co-Authors: Richard N Brown, Mark A. Peot, Robert S. LaneAbstract:Lyme borreliosis is associated with several genospecies of Borrelia burgdorferi sensu lato (s.l.) (Spirochaetales), but human disease has been associated only withBorreliaburgdorferi sensu stricto (s.s.) Johnson, Schmid, Hyde, Steigerwalt & Brenner in the western United States. Restriction fragment length polymorphism (RFLP) analysis of rrf-rrl amplicons from 124 tick and mammalian isolates from various habitats yielded 13 RFLP patterns. Of these patterns, six were patterns previously associated either with Borrelia bissettii Postic, Marti Ras, Lane, Hendson & Baranton or Borrelia burgdorferi s.s., and the remaining seven patterns belonged to diverse and previously uncharacterized Borrelia spp. Uncharacterized Borrelia spp. were cultured most frequently from Ixodes spinipalpis Hadwen & Nuttall and California kangaroo rats, Dipodomys californicus Merriam, inhabiting grass- lands, andB.bissettii fromI.spinipalpis and dusky-footed woodrats,Neotoma fuscipes Baird, associated with oak woodlands or chaparral. B. burgdorferi s.s. typically was isolated from host-seeking Ixodes pacificus Cooley & Kohls collected in dense oak woodlands, woodlandÐ grass, or redwood forests. Although some isolates of B. burgdorferi s.s. were cultured from woodrats, there was no clear association of this human pathogen with any vertebrate host. These Þndings, along with recent evidence indicating that the western gray squirrel, Sciurus griseus Ord, may be an important reservoir of B. burgdorferi s.s. in Californian oak woodlands, suggest that our earlier hypothesis implicating an enzootic cycle involving woodrats and I. spinipalpis is insufÞcient to account for observed patterns of infection in nature.
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Common ancestry of Borrelia burgdorferi sensu lato strains from North America and Europe.
Journal of clinical microbiology, 1999Co-Authors: D. Postic, Robert S. Lane, N. Marti Ras, P.-f. Humair, M. M. Wittenbrink, G. BarantonAbstract:Ten atypical European Borrelia burgdorferi sensu lato (Borrelia spp.) strains were genetically characterized, and the diversity was compared to that encountered among related Borrelia spp. from North America. Phylogenetic analyses of a limited region of the genome and of the whole genome extend existing knowledge about Borrelial diversity reported earlier in Europe and the United States. Our results accord with the evidence that North American and European strains may have a common ancestry.
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lyme disease in california a novel enzootic transmission cycle of Borrelia burgdorferi
Science, 1992Co-Authors: R N Brown, Robert S. LaneAbstract:Knowledge of zoonotic transmission cycles is essential for the development of effective strategies for disease prevention. The enzootiology of Lyme disease in California differs fundamentally from that reported from the eastern United States. Woodrats, not mice, serve as reservoir hosts, and Ixodes neotomae, a nonhuman-biting tick, maintains the agent of Lyme disease, Borrelia burgdorferi, in enzootic cycles. The western black-legged tick, Ixodes pacificus, is the primary vector to humans, but it appears to be an inefficient maintenance vector. Isolates of B. burgdorferi from California exhibit considerable antigenic heterogeneity, and some isolates differ strikingly from isolates recovered from this and other geographic regions.