Lack of evidence for bacterial infections in skin in patients with systemic sclerosis.

BACKGROUND: 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. METHODS: Chlamydiae of many species are known to undergo persistent infection. Highly sensitive and specific PCR assays targeting chromosomal DNA sequences from C. trachomatis and C. pneumoniae were used to screen skin biopsy samples from each of 18 patients and 26 control individuals. Additional screening was performed using a highly sensitive "pan-bacteria" PCR screening system. RESULTS: All patient and control samples proved to be PCR-negative for both chlamydial species. Similarly, all patient and control samples were PCR-negative when the broad range pan-bacteria assay system was used. CONCLUSION: Although some caveats apply, the data presented here do not support the contention that persistent bacterial infections play an important role in the pathogenesis of SSc.

Chlamydophila (Chlamydia) pneumoniae in the Alzheimer's brain.

We assessed the presence and characteristics of the intracellular pathogen Chlamydophila (Chlamydia) pneumoniae in brain-tissue samples from 25 patients with late-onset Alzheimer's disease (AD) and 27 non-AD control individuals. 20/27 AD patients, but only 3/27 controls, were PCR-positive in multiple assays targetting the Cpn1046 and Cpn0695 genes. Culture of the organism from brain-tissue homogenate from one AD patient, and assessment of various chlamydial transcripts in RNA preparations from several patients, demonstrated that the organisms were viable and metabolically active in those samples. Immunohistochemical analyses showed that astrocytes, microglia, and neurons all served as host cells for C. pneumoniae in the AD brain, and that infected cells were found in close proximity to both neuritic senile plaques and neurofibrillary tangles in the AD brain. These observations confirm and significantly extend our earlier study suggesting that this unusual pathogen may play a role in the neuropathogenesis characteristic of AD.

Functional CCR5 receptor protects patients with arthritis from high synovial burden of infecting Chlamydia trachomatis.

INTRODUCTION: 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. METHODS: Polymerase chain reaction (PCR) defined CCR5 genotype in synovial tissue DNA from 218 individuals: 21 controls, 110 with reactive arthritis (ReA), 83 with undifferentiated oligoarthritis (UO), 4 with osteoarthritis (OA). Disease durations were 0.5 to 21 years. Additional PCR assays defined the presence of C trachomatis DNA. Bacterial load was assessed by real-time PCR in selected samples. RESULTS: Five controls were wt/Δ32, 16 were wt/wt; 2 of 21 controls (both wt/wt) were PCR positive for C trachomatis. Eighty-five (44%) patients with arthritis were PCR positive for C trachomatis (69 ReA and 16 UO). For patients with ReA, 14 (13%) had wt/Δ32, 10 (71%) of whom were PCR positive. Nineteen patients with UO (23%) were wt/Δ32, with 1 (1%) PCR positive. No differences existed for gender or other factors. One patient with OA had wt/Δ32. In ReA and UO samples, wt/Δ32 heterozygotes had a 5- to 10-fold higher bacterial burden than did wt/wt patients (P = 0.03), regardless of diagnosis. CONCLUSION: These results indicate that the wt/wt genotype is associated with attenuated synovial bacterial load compared with loads in wt/Δ32 patients. Although no alleles other than Δ32 were assessed, our data suggest that this allele provides little/no protection from ReA in patients infected with Chlamydia- but it may provide some protection in patients with UO. The basis of this possible differential effect of CCR5 genotype is under study.

Chlamydiae as etiologic agents in chronic undifferentiated spondylarthritis.

OBJECTIVE: The majority of patients with Chlamydia-induced reactive arthritis do not present with the classic triad of arthritis, conjunctivitis/iritis, and urethritis. Moreover, acute chlamydial infections are often asymptomatic. The aim of the present study was to assess the prevalence of synovial Chlamydia trachomatis and Chlamydia pneumoniae infections in patients with chronic undifferentiated spondylarthritis (uSpA). METHODS: Study patients met the European Spondylarthropathy Study Group criteria for SpA, without evidence of ankylosing spondylitis, psoriasis, inflammatory bowel disease, or preceding dysentery. Symptoms were present for >or=6 months. Each patient underwent a synovial biopsy; tissue and concomitantly obtained peripheral blood mononuclear cells (PBMCs) were analyzed by polymerase chain reaction (PCR) for C trachomatis and C pneumoniae DNA. Other data collected on the day of the biopsy included standard demographic information and medical history, including any known history of C trachomatis or C pneumoniae. Physical examination (including joint count, evaluation for dactylitis and/or enthesitis, and skin examination) and HLA-B27 typing were performed. Synovial tissue (ST) samples from 167 patients with osteoarthritis (OA) were used as controls. RESULTS: Twenty-six patients met the entry criteria and underwent synovial biopsy (25 knee, 1 wrist). Sixteen of them (62%) were positive for C trachomatis and/or C pneumoniae DNA (10 for C trachomatis, 4 for C pneumoniae, and 2 for both). PCR analysis of ST revealed the presence of Chlamydia significantly more frequently in patients with uSpA than in OA controls (P<0.0001). No specific clinical characteristics differentiated Chlamydia-positive from Chlamydia-negative patients. PBMCs from 4 of the 26 uSpA patients (15%) were positive for Chlamydia, and Chlamydia was found in ST from 2 of these 4 patients. No significant correlation between PCR positivity and HLA-B27 positivity was found. CONCLUSION: The frequency of Chlamydia-positive ST samples, as determined by PCR, was found to be significantly higher in patients with uSpA than in patients with OA. Our results suggest that in many patients with uSpA, chlamydial infection, which is often occult, may be the cause.

The YJR127C/ZMS1 gene product is involved in glycerol-based respiratory growth of the yeast Saccharomyces cerevisiae.

A putative yeast mitochondrial upstream activating sequence (UAS) was used in a one-hybrid screening procedure that identified the YJR127C ORF on chromosome X. This gene was previously designated ZMS1 and is listed as a transcription factor on the SGD website. Real time RT-PCR assays showed that expression of YJR127C/ZMS1 was glucose-repressible, and a deletion mutant for the gene showed a growth defect on glycerol-based but not on glucose- or ethanol-based medium. Real time RT-PCR analyses identified severely attenuated transcript levels from GUT1 and GUT2 to be the source of that growth defect, the products of GUT1 and GUT2 are required for glycerol utilization. mRNA levels from a large group of mitochondria- and respiration-related nuclear genes also were shown to be attenuated in the deletion mutant. Importantly, transcript levels from the mitochondrial OLI1 gene, which has an associated organellar UAS, were attenuated in the DeltaYJR127C mutant during glycerol-based growth, but those from COX3 (OXI2), which lacks an associated mitochondrial UAS, were not. Transcriptome analysis of the glycerol-grown deletion mutant showed that genes in several metabolic and other categories are affected by loss of this gene product, including protein transport, signal transduction, and others. Thus, the product of YJR127C/ZMS1 is involved in transcriptional control for genes in both cellular genetic compartments, many of which specify products required for glycerol-based growth, respiration, and other functions.