Front Aging Neurosci
October 2018
The disease known as late-onset Alzheimer's disease is a neurodegenerative condition recognized as the single most commonform of senile dementia. The condition is sporadic and has been attributed to neuronal damage and loss, both of which have been linked to the accumulation of protein deposits in the brain. Significant progress has been made over the past two decades regarding our overall understanding of the apparently pathogenic entities that arise in the affected brain, both for early-onset disease, which constitutes approximately 5% of all cases, as well as late-onset disease, which constitutes the remainder of cases.
View Article and Find Full Text PDFPeptide-based vaccines have emerged in recent years as promising candidates in the prevention of infectious diseases. However, there are many challenges to maintaining in vivo peptide stability and enhancement of peptide immunogenicity to generate protective immunity which enhances clearance of infections. Here, a dendrimer-based carrier system is proposed for peptide-based vaccine delivery, and shows its anti-microbial feasibility in a mouse model of Chlamydia trachomatis.
View Article and Find Full Text PDFChlamydia trachomatis is an intracellular human pathogen that causes a sexually transmitted disease which may result in an inflammatory arthritis designated Chlamydia-induced reactive arthritis (ReA). The arthritis develops after dissemination of infected cells from the initial site of chlamydial infection. During Chlamydia-associated ReA, the organism may enter into a persistent infection state making treatment with antibiotics a challenge.
View Article and Find Full Text PDFLack of a system for genetic manipulation of Chlamydia trachomatis has been a key challenge to advancing understanding the molecular genetic basis of virulence for this bacterial pathogen. We developed a non-viral, dendrimer-enabled system for transformation of this organism and used it to characterize the effects of inserting the common 7.5 kbp chlamydial plasmid into strain L2(25667R), a C.
View Article and Find Full Text PDFUnlabelled: The chlamydiae are important human pathogens. Lack of a genetic manipulation system has impeded understanding of the molecular bases of virulence for these bacteria. We developed a dendrimer-enabled system for transformation of chlamydiae and used it to characterize the effects of inserting the C.
View Article and Find Full Text PDFInt J Clin Rheumtol
December 2012
Genital Chlamydia trachomatis infections can elicit an inflammatory arthritis in some individuals, and recent surprising studies have demonstrated that only ocular (trachoma) strains, not genital strains, of the organism are present in the synovial tissues of patients with the disease. This observation suggests an explanation for the small proportion of genitally-infected patients who develop Chlamydia-induced arthritis. Other recent studies have begun to identify the specific chlamydial gene products that elicit the synovial inflammatory response during both active and quiescent disease, although much more study will be required to complete the understanding of that complex process of host-pathogen interaction.
View Article and Find Full Text PDFThe obligate intracellular bacterium Chlamydia trachomatis is an important human pathogen. The genome of this organism is small but encodes many genes of currently unknown function that are thought to be involved in virulence. Lack of a system for genetic manipulation has been a key challenge to advancing the understanding of molecular genetics underlying virulence for this bacterium.
View Article and Find Full Text PDFThe inflammatory arthritis that develops in some patients subsequent to urogenital infection by the obligate intracellular bacterial pathogen Chlamydia trachomatis, and that induced subsequent to pulmonary infection with C. pneumoniae, both have proved difficult to treat in either their acute or chronic forms. Over the last two decades, molecular genetic and other studies of these pathogens have provided a good deal of information regarding their metabolic and genetic structures, as well as the detailed means by which they interact with their host cells.
View Article and Find Full Text PDFUnlabelled: Chlamydia trachomatis is an important bacterial pathogen known to be etiological in genital infections, as well as several serious disease sequelae, including inflammatory arthritis. Chlamydiae can persist in infection, making treatment with antibiotics such as azithromycin (AZ) a challenge. The authors explore the use of neutral generation-4 polyamidoamine (PAMAM) dendrimers as intracellular drug-delivery vehicles into chlamydial inclusions.
View Article and Find Full Text PDFChlamydia trachomatis and Chlamydia pneumoniae are intracellular bacterial pathogens that have been shown to cause, or are strongly associated with, diverse chronic diseases. Persistent infections by both organisms are refractory to antibiotic therapy. The lack of therapeutic efficacy results from the attenuated metabolic rate of persistently infecting chlamydiae in combination with the modest intracellular drug concentrations achievable by normal delivery of antibiotics to the inclusions within which chlamydiae reside in the host cell cytoplasm.
View Article and Find Full Text PDFIntroduction: The CCR5 chemokine receptor occurs in a wild-type (wt) and a nonfunctional deleted form (Δ32). Reports suggested that Chlamydia-induced reproductive tract pathology is attenuated in women bearing Δ32. The authors asked whether the mutation affects synovial prevalence and burden of Chlamydia trachomatis.
View Article and Find Full Text PDFA novel strategy for pulmonary delivery of polymeric nanocarriers (NCs) pressurized-metered dose inhalers (pMDIs) is reported in this work. Core-shell particles consisting of a water soluble, hydrofluoroalkane(HFA)-philic biodegradable copolymer of chitosan and poly(lactic acid), and a core of poly(d,l-lactide-co-glycolide) (PLGA) NCs were prepared by a modified emulsification-diffusion methodology. Dispersions of the core-shell particles in HFA propellant revealed enhanced physical stability compared to polymeric NCs alone, and more importantly, excellent aerosol characteristics as determined by inertial impaction studies.
View Article and Find Full Text PDFIn all animal models for chlamydial infection, there is strong evidence for immunity to reinfection; however, immunity is only complete (ie, preventing infection) in the short term. In the long term, animals are only partially immune (ie, they can be reinfected, but infections are usually abbreviated and less intense than the primary infection). This review will target the mechanisms responsible for long-term versus short-term immunity and explore the roles of various components of the host response in immunity to chlamydial genital infection.
View Article and Find Full Text PDFPurpose Of Review: Topics relating to the spondyloarthropathies have been reviewed recently, but the detailed roles of Chlamydia trachomatis and C. pneumoniae in induction of spondyloarthritis have not been discussed. This review focuses on new information regarding how these pathogens elicit joint disease, with emphasis on C.
View Article and Find Full Text PDFSome individuals with a genital Chlamydia trachomatis infection develop inflammatory arthritis, but it is unknown whether particular chlamydial serovar(s) engender the disease more often than others. We defined serovar in synovial tissues from arthritis patients infected with this organism. DNA from synovial biopsies of 36 patients with PCR-confirmed synovial C.
View Article and Find Full Text PDFA crucial process of chlamydial development involves differentiation of the replicative reticulate body (RB) into the infectious elementary body (EB). We present experimental evidence to provide support for a contact-dependent hypothesis for explaining the trigger involved in differentiation. We recorded live-imaging of Chlamydia trachomatis-infected McCoy cells at key times during development and tracked the temporospatial trajectories of individual chlamydial particles.
View Article and Find Full Text PDFSevere and chronic inflammatory arthritis sometimes follows urogenital infection with Chlamydia trachomatis or gastrointestinal infection with enteric bacterial pathogens. A similar clinical entity can be elicited by the respiratory pathogen Chlamydophila (Chlamydia) pneumoniae. Arthritogenesis does not universally require viable enteric bacteria in the joint.
View Article and Find Full Text PDFBackground: In some patients with systemic sclerosis (SSc), persistent bacterial infection involving dermal microvascular endothelial cells may result in endothelial injury, leading to the obliterative microvasculopathy typical of the disease. Alternatively, in some patients with SSc persistent bacterial infection involving activated dermal fibroblasts or other cells found in scleroderma skin might result in the fibrosing features of this disease. In this study, we investigated bacterial infection in skin in patients with SSc.
View Article and Find Full Text PDFPrevious studies from this laboratory provided evidence that the intracellular bacterial pathogen Chlamydophila (Chlamydia) pneumoniae is present in the late-onset Alzheimer's disease (AD) brain. Here we report culture of the organism from two AD brain samples, each of which originated from a different geographic region of North America. Culturable organisms were detectable after one and two passages in HEp-2 cells for the two samples.
View Article and Find Full Text PDFSporadic, late-onset Alzheimer's disease (LOAD) is a non-familial, progressive neurodegenerative disease that is now the most common and severe form of dementia in the elderly. That dementia is a direct result of neuronal damage and loss associated with accumulations of abnormal protein deposits in the brain. Great strides have been made in the past 20 years with regard to understanding the pathological entities that arise in the AD brain, both for familial AD ( approximately 5% of all cases) and LOAD ( approximately 95% of all cases).
View Article and Find Full Text PDFOral Surg Oral Med Oral Pathol Oral Radiol Endod
June 2008
Background: Conflicting results have been reported regarding the presence or absence of estrogen-binding sites (EBS) in the human temporomandibular joint (TMJ). The possible role of female sex hormones in the pathophysiology of internal derangement of the TMJ has been suggested to explain the prevalence of TMJ symptoms in female patients.
Patients And Methods: Posterior bilaminar tissue excised during TMJ articular disc repositioning and posterior ligament repair was taken from 28 patients (26 female, 2 male) for evaluation.
Purpose: MRL/MpJ mice of substrains MRL/MpJ-fas(+)/fas(+) (MRL/+) and MRL/MpJ-fas(lpr)/fas(lpr) (MRL/lpr) spontaneously develop autoimmune dacryoadenitis and sialadenitis and are a model for the human disorder Sjögren syndrome. The dacryoadenitis in both substrains appears to be Th2 in nature, with little IFN-gamma and substantial IL-4 at the site of lacrimal gland inflammation.
Methods: MRL/MpJ mice with a defective IL-4 gene-both MRL/+-IL-4(tm)/IL-4(tm) (MRL/+/IL-4(tm)) and MRL/lpr-IL-4(tm)/IL-4(tm) (MRL/lpr-IL-4(tm))-that resulted in a loss of IL-4 production were bred and evaluated for dacryoadenitis.
Chlamydophila (Chlamydia) pneumoniae is an intracellular respiratory pathogen known to cause community-acquired pneumonia. Infection with this organism has been associated with atherosclerosis, inflammatory arthritis, and other chronic diseases, many of which also have been associated with possession of the epsilon4 allele at the APOE locus on (human) chromosome 19. An earlier study from this laboratory suggested that some relationship exists between apolipoprotein E4 (apoE4), the product of the epsilon4 allele, and the pathobiology of C.
View Article and Find Full Text PDFOral Surg Oral Med Oral Pathol Oral Radiol Endod
July 2007
Objective: The objective of this study was to determine if temporomandibular joint (TMJ) samples positive for Chlamydia trachomatis have a greater presence of tumor necrosis factor-alpha (TNFalpha) or interleukin-6 (IL-6) when compared with Chlamydia-negative samples.
Study Design: Posterior bilaminar tissue samples removed during TMJ surgery from 70 patients were evaluated. Cryosections were stained using monoclonal antibody that identifies C.