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Parasites & Vectors Feb 2021The incidence of Lyme borreliosis varies over time and space through as yet incompletely understood mechanisms. In Europe, Lyme borreliosis is caused by infection with a...
BACKGROUND
The incidence of Lyme borreliosis varies over time and space through as yet incompletely understood mechanisms. In Europe, Lyme borreliosis is caused by infection with a Borrelia burgdorferi (s.l.) genospecies, which is primarily transmitted by a bite of Ixodes ricinus nymphs. The aim of this study was to investigate the spatial and temporal variation in nymphal infection prevalence of B. burgdorferi (s.l.) (NIP), density of questing nymphs (DON) and the resulting density of infected nymphs (DIN).
METHODS
We investigated the infection rates in I. ricinus nymphs that were collected monthly between 2009 and 2016 in 12 locations in the Netherlands. Using generalized linear mixed models, we explored how the NIP, DON and DIN varied during the seasons, between years and between locations. We also determined the genospecies of the Borrelia infections and investigated whether the genospecies composition differed between locations.
RESULTS
The overall NIP was 14.7%. A seasonal pattern in infection prevalence was observed, with higher estimated prevalences in the summer than in the spring and autumn. This, combined with higher nymphal densities in summer, resulted in a pronounced summer peak in the estimated DIN. Over the 7.5-year study period, a significant decrease in infection prevalence was found, as well as a significant increase in nymphal density. These two effects appear to cancel each other out; the density of infected nymphs, which is the product of NIP × DON, showed no significant trend over years. Mean infection prevalence (NIP, averaged over all years and all months) varied considerably between locations, ranging from 5 to 26%. Borrelia genospecies composition differed between locations: in some locations almost all infections consisted of B. afzelii, whereas other locations had more diverse genospecies compositions.
CONCLUSION
In the Netherlands, the summer peak in DIN is a result of peaks in both NIP and DON. No significant trend in DIN was observed over the years of the study, and variations in DIN between locations were mostly a result of the variation in DON. There were considerable differences in acarological risk between areas in terms of infection prevalence and densities of ticks as well as in Borrelia genospecies composition.
Topics: Animals; Borrelia; Borrelia burgdorferi; Ixodes; Netherlands; Nymph; Seasons
PubMed: 33627166
DOI: 10.1186/s13071-021-04607-7 -
Current Opinion in Microbiology Aug 2023The Lyme disease spirochete persists in nature through cycles between ticks and vertebrates. Although the spirochete interacts with numerous, distinct tissues and... (Review)
Review
The Lyme disease spirochete persists in nature through cycles between ticks and vertebrates. Although the spirochete interacts with numerous, distinct tissues and environmental conditions during its infectious cycle, Borrelia burgdorferi appears to possess a limited ability to sense its external environment. This apparent paradox is being resolved through detailed investigations of the molecular mechanisms through which B. burgdorferi controls production of virulence-associated factors such as the Erp outer surface proteins. The results have led to development of a model for how B. burgdorferi controls expression of its diverse proteins, wherein physiological and metabolic states that are unique to specific points in the infectious cycle trigger changes in gene and protein expression levels.
Topics: Animals; Borrelia burgdorferi; Bacterial Proteins; Ticks; Lyme Disease
PubMed: 37279610
DOI: 10.1016/j.mib.2023.102332 -
Archives of Dermatological Research Mar 2018Skin fibrosis has been reported in Borrelia burgdorferi infection in Europe, but has been questioned by several authors. The objective of the present study was to...
Skin fibrosis has been reported in Borrelia burgdorferi infection in Europe, but has been questioned by several authors. The objective of the present study was to examine the interaction of skin fibroblasts with B. burgdorferi sensu stricto B31 (BB) and B. afzelii (BA) in vitro by electron microscopy. We also determined the expression of collagen type I, TGF-β, FGF-1, calreticulin (CALR), decorin (DCN), and PDGF-α at the mRNA level in Borrelia/fibroblast co-cultures. Intact Borrelia attach to and transmigrate fibroblasts, and undergo cystic transformation outside the fibroblasts. Fibroblasts preserve their vitality and express a prominent granular endoplasmic reticulum, suggesting activated protein synthesis. On two different semi-quantitative real-time PCR assays, BB- and BA/fibroblast co-cultures showed a significant induction of type I collagen mRNA after 2 days compared to fibroblasts (fourfold for BA and 1.8-fold for BB; p < 0.02). In addition, there was a significant upregulation of mRNA expression of TGF-β, CALR, PDGF-α, and DCN in BA and BB co-cultures compared to control fibroblasts in monolayer cultures after 2 days (p < 0.01). The BA/fibroblast co-culture induced a considerably greater upregulation of collagen and growth factor mRNA compared to BB/fibroblast co-culture. In contrast, a significant down-regulation of FGF-1 (20-fold for BA and 4.5-fold for BB) mRNA expression was detected in co-cultures compared to controls (p < 0.01). The results of the study support the hypothesis that BB sensu lato, and BA in particular, enhances collagen mRNA expression and can stimulate growth factors responsible for increased collagen production.
Topics: Animals; Borrelia burgdorferi; Cell Line; Cells, Cultured; Coculture Techniques; Collagen; Down-Regulation; Fibroblasts; Fibrosis; Humans; Intercellular Signaling Peptides and Proteins; Microscopy, Electron; RNA, Messenger; Skin; Transforming Growth Factor beta
PubMed: 29214350
DOI: 10.1007/s00403-017-1797-1 -
Biomedical and Environmental Sciences :... May 2021To study the polymorphism in P66 and its human B-cell epitopes of strains in China.
OBJECTIVE
To study the polymorphism in P66 and its human B-cell epitopes of strains in China.
METHODS
Polymerase chain reaction (PCR) and sequencing were used to obtain the P66 sequences of 59 Chinese . Then the sequences were analyzed by MEGA 5.10 software and compared with the human B-cell epitope sequences from the Immune Epitope Database (IEDB) based on the reference strain of each genotype.
RESULTS
Results showed that genetic and amino acid diversity presented in the 66 kD protein of all 59 Chinese strains, especially in ( ) and ( ) strains. strains were divided into three subclusters and two scattered strains JC1-7 and JC2-2 according to the amino acid sequences of P66. The P66 sequences of 15 Xinjiang strains represented by XI91-12 in the subcluster 1, changed from CAA to TAA codon at 508aa position, resulting in early termination. Bases A and C were inserted at sequence position 1 523 bp of strains FP1, LB20, LB21, and SZ21 in the genotype, which resulted to early termination at position 511 aa. G base was inserted at 438 bp of LIP94-11 strain, which led to early termination at position 172 aa.
CONCLUSION
In P66 of 59 Chinese strains, polymorphisms were widely distributed. More importantly, the P66 amino acid sequences of strains had a certain regional character. One of the characteristics of Xinjiang isolates might be the variation at the 508aa location in 15 Xinjiang strains, which may be related to the strains' pathogenicity in this area.
Topics: Bacterial Proteins; Borrelia burgdorferi; China; Cluster Analysis; Epitopes, B-Lymphocyte; Genetic Markers; Genotype; Humans; Mutation; Polymerase Chain Reaction; Polymorphism, Genetic; Porins
PubMed: 34059173
DOI: 10.3967/bes2021.048 -
Ticks and Tick-borne Diseases Sep 2011Borrelia burgdorferi sensu lato (s.l.) complex is a diverse group of worldwide distributed bacteria that includes 18 named spirochete species and a still not named group... (Review)
Review
Borrelia burgdorferi sensu lato (s.l.) complex is a diverse group of worldwide distributed bacteria that includes 18 named spirochete species and a still not named group proposed as genomospecies 2. Descriptions of new species and variants continue to be recognized, so the current number of described species is probably not final. Most of known spirochete species are considered to have a limited distribution. Eleven species from the B. burgdorferi s.l. complex were identified in and strictly associated with Eurasia (B. afzelii, B. bavariensis, B. garinii, B. japonica, B. lusitaniae, B. sinica, B. spielmanii, B. tanukii, B. turdi, B. valaisiana, and B. yangtze), while another 5 (B. americana, B. andersonii, B. californiensis, B. carolinensis, and B. kurtenbachii) were previously believed to be restricted to the USA only. B. burgdorferi sensu stricto (s.s.), B. bissettii, and B. carolinensis share the distinction of being present in both the Old and the New World. Out of the 18 genospecies, 3 commonly and 4 occasionally infect humans, causing Lyme borreliosis (LB) - a multisystem disease that is often referred to as the 'great imitator' due to diversity of its clinical manifestations. Among the genospecies that commonly infect people, i.e. B. burgdorferi s.s., B. afzelii, and B. garinii, only B. burgdorferi s.s. causes LB both in the USA and in Europe, with a wide spectrum of clinical conditions ranging from minor cutaneous erythema migrans (EM) to severe arthritis or neurological manifestations. The epidemiological data from many European countries and the USA show a dramatic increase of the diagnosed cases of LB due to the development of new progressive diagnostic methods during the last decades (Hubálek, 2009). Recently, the definition of the disease has also changed. What was not considered Lyme borreliosis before might be now.
Topics: Animals; Arachnid Vectors; Asia; Bacterial Typing Techniques; Birds; Borrelia burgdorferi; DNA, Bacterial; Disease Reservoirs; Europe; Genetic Variation; Humans; Lyme Disease; Phylogeny; Phylogeography; Polymerase Chain Reaction; Public Health; Rodentia; Species Specificity; Ticks; United States
PubMed: 21890064
DOI: 10.1016/j.ttbdis.2011.04.002 -
The Yale Journal of Biology and Medicine Jun 2017() and closely related genospecies are the causative agents of Lyme disease, the most common tick-borne disease north of the equator. The bacterium, a member of the... (Review)
Review
() and closely related genospecies are the causative agents of Lyme disease, the most common tick-borne disease north of the equator. The bacterium, a member of the spirochete phylum, is acquired by a tick vector that feeds on an infected vertebrate host and is transmitted to another vertebrate during subsequent feeding by the next tick stage. The precise navigation of this enzootic cycle entails the regulation of genes required for these two host-specific phases as well as the transitions between them. Recently, an expansive swath of small RNAs has been identified in and likely many, if not most, are involved in regulating gene expression. Regardless, with only a few exceptions, the functions of these RNAs are completely unknown. However, several state-of-the-art approaches are available to identify the targets of these RNAs and provide insight into their role in the enzootic cycle and infection.
Topics: Borrelia burgdorferi; Humans; Lyme Disease; RNA, Antisense; RNA, Small Untranslated
PubMed: 28656017
DOI: No ID Found -
Microbiology (Reading, England) Nov 2016The spirochaete bacterium Borrelia burgdorferisensu lato is the aetiologic agent of Lyme disease. Borrelia is transmitted to mammals through tick bite and is adapted to...
The spirochaete bacterium Borrelia burgdorferisensu lato is the aetiologic agent of Lyme disease. Borrelia is transmitted to mammals through tick bite and is adapted to survive at tick and mammalian physiological temperatures. We have previously shown that B. burgdorferi can exist in different morphological forms, including the antibiotic-resistant biofilm form, in vitro and in vivo. B. burgdorferi forms aggregates in ticks as well as in humans, indicating potential of biofilm formation at both 23 and 37 °C. However, the role of various environmental factors that influence Borrelia biofilm formation remains unknown. In this study, we investigated the effect of tick (23 °C), mammalian physiological (37 °C) and standard in vitro culture (33 °C) temperatures with the objective of elucidating the effect of temperature on Borrelia biofilm phenotypes invitro using two B. burgdorferisensu stricto strains (B31 and 297). Our findings show increased biofilm quantity, biofilm size, exopolysaccharide content and enhanced adherence as well as reduced free spirochaetes at 37 °C for both strains, when compared to growth at 23 and 33 °C. There were no significant variations in the biofilm nano-topography and the type of extracellular polymeric substance in Borrelia biofilms formed at all three temperatures. Significant variations in extracellular DNA content were observed in the biofilms of both strains cultured at the three temperatures. Our results indicate that temperature is an important regulator of Borrelia biofilm development, and that the mammalian physiological temperature favours increased biofilm formation in vitro compared to tick physiological temperature and in vitro culture temperature.
Topics: Animals; Biofilms; Body Temperature; Borrelia burgdorferi; Humans; Lyme Disease; Ticks
PubMed: 27902419
DOI: 10.1099/mic.0.000380 -
Current Protocols in Microbiology Aug 2014Borrelia burgdorferi sensu lato is a group of spirochetes belonging to the genus Borrelia in the family of Spirochaetaceae. The spirochete is transmitted between...
Borrelia burgdorferi sensu lato is a group of spirochetes belonging to the genus Borrelia in the family of Spirochaetaceae. The spirochete is transmitted between reservoirs and hosts by ticks of the family Ixodidae. Infection with B. burgdorferi in humans causes Lyme disease or Lyme borreliosis. Currently, 20 Lyme disease-associated Borrelia species and more than 20 relapsing fever-associated Borrelia species have been described. Identification and differentiation of different Borrelia species and strains is largely dependent on analyses of their genetic characteristics. A variety of molecular techniques have been described for Borrelia isolate speciation, molecular epidemiology, and pathogenicity studies. In this unit, we focus on three basic protocols, PCR-RFLP-based typing of the rrs-rrlA and rrfA-rrlB ribosomal spacer, ospC typing, and MLST. These protocols can be employed alone or in combination for characterization of B. burgdorferi isolates or directly on uncultivated organisms in ticks, mammalian host reservoirs, and human clinical specimens.
Topics: Bacterial Outer Membrane Proteins; Bacterial Typing Techniques; Borrelia burgdorferi; Molecular Typing; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; RNA, Bacterial; RNA, Ribosomal
PubMed: 25082003
DOI: 10.1002/9780471729259.mc12c05s34 -
Arthritis and Rheumatism Aug 2006Myositis has been reported as a rare manifestation of Lyme disease, and Lyme myositis can be an important consideration in the differential diagnosis of unusual cases,...
Myositis has been reported as a rare manifestation of Lyme disease, and Lyme myositis can be an important consideration in the differential diagnosis of unusual cases, especially in patients who live in or travel to endemic areas. We report the case of a 43-year-old man who presented with focal myositis of the proximal lower extremity and was subsequently diagnosed as having Lyme myositis. The patient had previously experienced a febrile illness and rash, but had no ongoing symptoms of Lyme disease. Myositis was confirmed by magnetic resonance imaging and muscle biopsy; Borrelia burgdorferi infection was confirmed by Lyme serology and polymerase chain reaction testing of synovial fluid and biopsy material. The current case is reviewed in the context of findings from previous case descriptions.
Topics: Adult; Anti-Bacterial Agents; Antibodies, Bacterial; Borrelia burgdorferi; Ceftriaxone; DNA, Bacterial; Humans; Lower Extremity; Lyme Disease; Magnetic Resonance Imaging; Male; Myositis; Reference Values; Treatment Outcome
PubMed: 16871548
DOI: 10.1002/art.22007 -
Infection and Immunity Sep 2021Riboflavin is an essential micronutrient, but its transport and utilization have remained largely understudied among pathogenic spirochetes. Here, we show that Borrelia...
Riboflavin is an essential micronutrient, but its transport and utilization have remained largely understudied among pathogenic spirochetes. Here, we show that Borrelia burgdorferi, the zoonotic spirochete that causes Lyme disease, is able to import riboflavin via products of its -like operon as well as synthesize flavin mononucleotide and flavin adenine dinucleotide despite lacking canonical genes for their synthesis. Additionally, a mutant deficient in the -like operon is resistant to the antimicrobial effect of roseoflavin, a natural riboflavin analog, and is attenuated in a murine model of Lyme borreliosis. Our combined results indicate not only that are riboflavin and the maintenance of flavin pools essential for B. burgdorferi growth but also that flavin utilization and its downstream products (e.g., flavoproteins) may play a more prominent role in B. burgdorferi pathogenesis than previously appreciated.
Topics: Animals; Bacterial Proteins; Borrelia burgdorferi; Female; Lyme Disease; Mammals; Mice; Mice, Inbred C3H; Operon; Riboflavin
PubMed: 34310888
DOI: 10.1128/IAI.00307-21