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1.
J Fungi (Basel) ; 8(8)2022 Aug 10.
Article in English | MEDLINE | ID: mdl-36012826

ABSTRACT

Coccidioidomycosis is an endemic fungal infection that is reported in up to 20,000 persons per year and has an economic impact close to $1.5 billion. Natural infection virtually always confers protection from future exposure, and this suggests that a preventative vaccine strategy is likely to succeed. We here review progress toward that objective. There has been ongoing research to discover a coccidioidal vaccine over the past seven decades, including one phase III clinical trial, but for reasons of either efficacy or feasibility, a safe and effective vaccine has not yet been developed. This review first summarizes the past research to develop a coccidioidal vaccine. It then details the evidence that supports a live, gene-deletion vaccine candidate as suitable for further development as both a veterinary and a human clinical product. Finally, a plausible vaccine development plan is described which would be applicable to this vaccine candidate and also useful to other future candidates. The public health and economic impact of coccidioidomycosis fully justifies a public private partnership for vaccine development, and the development of a vaccine for this orphan disease will likely require some degree of public funding.

2.
PLoS Pathog ; 18(4): e1009832, 2022 04.
Article in English | MEDLINE | ID: mdl-35385558

ABSTRACT

Coccidioides spp. are mammalian fungal pathogens endemic to the Southwestern US and other desert regions of Mexico, Central and South America, with the bulk of US infections occurring in California and Arizona. In the soil, Coccidioides grows in a hyphal form that differentiates into 3-5 micron asexual spores (arthroconidia). When arthroconidia are inhaled by mammals they undergo a unique developmental transition from polar hyphal growth to isotropic expansion with multiple rounds of nuclear division, prior to segmentation, forming large spherules filled with endospores. Very little is understood about the molecular basis of spherule formation. Here we characterize the role of the conserved transcription factor Ryp1 in Coccidioides development. We show that Coccidioides Δryp1 mutants have altered colony morphology under hypha-promoting conditions and are unable to form mature spherules under spherule-promoting conditions. We analyze the transcriptional profile of wild-type and Δryp1 mutant cells under hypha- and spherule-promoting conditions, thereby defining a set of hypha- or spherule-enriched transcripts ("morphology-regulated" genes) that are dependent on Ryp1 for their expression. Forty percent of morphology-regulated expression is Ryp1-dependent, indicating that Ryp1 plays a dual role in both hyphal and spherule development. Ryp1-dependent transcripts include key virulence factors such as SOWgp, which encodes the spherule outer wall glycoprotein. Concordant with its role in spherule development, we find that the Δryp1 mutant is completely avirulent in the mouse model of coccidioidomycosis, indicating that Ryp1-dependent pathways are essential for the ability of Coccidioides to cause disease. Vaccination of C57BL/6 mice with live Δryp1 spores does not provide any protection from lethal C. posadasii intranasal infection, consistent with our findings that the Δryp1 mutant fails to make mature spherules and likely does not express key antigens required for effective vaccination. Taken together, this work identifies the first transcription factor that drives mature spherulation and virulence in Coccidioides.


Subject(s)
Coccidioides , Transcription Factors , Animals , Coccidioides/genetics , Fungal Proteins , Gene Expression , Mammals , Mice , Mice, Inbred C57BL , Spores, Fungal/genetics , Transcription Factors/genetics , Virulence
3.
PLoS One ; 12(8): e0181998, 2017.
Article in English | MEDLINE | ID: mdl-28771520

ABSTRACT

Cassava (Manihot esculenta) is an important tropical subsistence crop that is severely affected by cassava brown streak disease (CBSD) in East Africa. The disease is caused by Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV). Both have a (+)-sense single-stranded RNA genome with a 5' covalently-linked viral protein, which functionally resembles the cap structure of mRNA, binds to eukaryotic translation initiation factor 4E (eIF4E) or its analogues, and then enable the translation of viral genomic RNA in host cells. To characterize cassava eIF4Es and their potential role in CBSD tolerance and susceptibility, we cloned five eIF4E transcripts from cassava (accession TMS60444). Sequence analysis indicated that the cassava eIF4E family of proteins consisted of one eIF4E, two eIF(iso)4E, and two divergent copies of novel cap-binding proteins (nCBPs). Our data demonstrated experimentally the coding of these five genes as annotated in the published cassava genome and provided additional evidence for refined annotations. Illumina resequencing data of the five eIF4E genes were analyzed from 14 cassava lines tolerant or susceptible to CBSD. Abundant single nucleotide polymorphisms (SNP) and biallelic variations were observed in the eIF4E genes; however, most of the SNPs were located in the introns and non-coding regions of the exons. Association studies of non-synonymous SNPs revealed no significant association between any SNP of the five eIF4E genes and the tolerance or susceptibility to CBSD. However, two SNPs in two genes were weakly associated with the CBSD responses but had no direct causal-effect relationship. SNPs in an intergenic region upstream of eIF4E_me showed a surprising strong association with CBSD responses. Digital expression profile analysis showed differential expression of different eIF4E genes but no significant difference in gene expression was found between susceptible and tolerant cassava accessions despite the association of the intergenic SNPs with CBSD responses.


Subject(s)
Disease Resistance/immunology , Eukaryotic Initiation Factor-4E/genetics , Genetic Variation/genetics , Manihot/immunology , Plant Diseases/immunology , Plants, Genetically Modified/immunology , Potyviridae/physiology , Disease Resistance/genetics , Host-Pathogen Interactions , Manihot/growth & development , Manihot/virology , Plant Diseases/virology , Plants, Genetically Modified/genetics , Plants, Genetically Modified/growth & development , RNA, Viral/genetics
4.
Adv Biosyst ; 1(10): e1700098, 2017 Oct.
Article in English | MEDLINE | ID: mdl-32646190

ABSTRACT

This work demonstrates for the first time rapid, real-time Mie scatter sensing of colloidal emulsion nucleic acid amplification directly from emulsion droplets. Loop-mediated isothermal amplification is used in this study, and, to our knowledge, has not previously been used in a colloidal emulsion platform. Interfacial tension values (γ) associated with bulk protein adsorption and denaturation at the oil-water interface exhibit characteristic changes in the absence or presence of amplification. In the presence of target and amplicon, emulsions maintain a constant 300-400 nm diameter, whereas emulsions formed with no target control show a rapid decrease in droplet diameter to <100 nm over the first 20 min of incubation. This method is validated using whole bacteria (Staphylococcus aureus MSSA and Escherichia coli O157:H7) and whole virus (Potato virus Y and Zika virus) samples suspended in water, buffer, or serum-like matrices. Short-term formation of colloidal emulsion is quantified via 60° scatter monitoring, where the initial slope of scattering intensity is utilized to confirm target amplification in less than 5 min. The unique benefits of this method render it more cost-effective and field-deployable than existing methods, while being adaptable to a multitude of targets, sample matrices, and nucleic acid amplification tests.

6.
Infect Immun ; 84(10): 3007-16, 2016 10.
Article in English | MEDLINE | ID: mdl-27481239

ABSTRACT

The CPS1 gene was identified as a virulence factor in the maize pathogen Cochliobolus heterostrophus Hypothesizing that the homologous gene in Coccidioides posadasii could be important for virulence, we created a Δcps1 deletion mutant which was unable to cause disease in three strains of mice (C57BL/6, BALB/c, or the severely immunodeficient NOD-scid,γc(null) [NSG]). Only a single colony was recovered from 1 of 60 C57BL/6 mice following intranasal infections of up to 4,400 spores. Following administration of very high doses (10,000 to 2.5 × 10(7) spores) to NSG and BALB/c mice, spherules were observed in lung sections at time points from day 3 to day 10 postinfection, but nearly all appeared degraded with infrequent endosporulation. Although the role of CPS1 in virulence is not understood, phenotypic alterations and transcription differences of at least 33 genes in the Δcps1 strain versus C. posadasii is consistent with both metabolic and regulatory functions for the gene. The in vitro phenotype of the Δcps1 strain showed slower growth of mycelia with delayed and lower spore production than C. posadasii, and in vitro spherules were smaller. Vaccination of C57BL/6 or BALB/c mice with live Δcps1 spores either intranasally, intraperitoneally, or subcutaneously resulted in over 95% survival with mean residual lung fungal burdens of <1,000 CFU from an otherwise lethal C. posadasii intranasal infection. Considering its apparently complete attenuation of virulence and the high degree of resistance to C. posadasii infection when used as a vaccine, the Δcps1 strain is a promising vaccine candidate for preventing coccidioidomycosis in humans or other animals.


Subject(s)
Coccidioides/physiology , Coccidioidomycosis/genetics , Sequence Deletion , Virulence Factors/genetics , Virulence/physiology , Animals , Coccidioides/genetics , Coccidioidomycosis/prevention & control , Disease Models, Animal , Female , Fungal Proteins/genetics , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Inbred NOD , Vaccination/methods
7.
Genome Res ; 19(10): 1722-31, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19717792

ABSTRACT

While most Ascomycetes tend to associate principally with plants, the dimorphic fungi Coccidioides immitis and Coccidioides posadasii are primary pathogens of immunocompetent mammals, including humans. Infection results from environmental exposure to Coccidiodies, which is believed to grow as a soil saprophyte in arid deserts. To investigate hypotheses about the life history and evolution of Coccidioides, the genomes of several Onygenales, including C. immitis and C. posadasii; a close, nonpathogenic relative, Uncinocarpus reesii; and a more diverged pathogenic fungus, Histoplasma capsulatum, were sequenced and compared with those of 13 more distantly related Ascomycetes. This analysis identified increases and decreases in gene family size associated with a host/substrate shift from plants to animals in the Onygenales. In addition, comparison among Onygenales genomes revealed evolutionary changes in Coccidioides that may underlie its infectious phenotype, the identification of which may facilitate improved treatment and prevention of coccidioidomycosis. Overall, the results suggest that Coccidioides species are not soil saprophytes, but that they have evolved to remain associated with their dead animal hosts in soil, and that Coccidioides metabolism genes, membrane-related proteins, and putatively antigenic compounds have evolved in response to interaction with an animal host.


Subject(s)
Coccidioides/genetics , Genome, Fungal , Mitosporic Fungi/genetics , Animals , Genetic Speciation , Genomics/methods , Histoplasma/genetics , Humans , Molecular Sequence Data , Onygenales/genetics , Phylogeny , Selection, Genetic , Sequence Analysis, DNA , Synteny
8.
J Neurol Sci ; 284(1-2): 116-9, 2009 Sep 15.
Article in English | MEDLINE | ID: mdl-19428028

ABSTRACT

OBJECTIVE: To determine the rate of treatment failure in patients outside of a controlled treatment trial and to ascertain the factors physicians used to make this decision. METHODS: One hundred and thirty four patients with the diagnosis of relapsing-remitting (RR) multiple sclerosis (MS) or clinically isolated symptom (CIS) enrolled in the CLIMB study (Comprehensive Longitudinal Investigation of Multiple Sclerosis at the Brigham and Women's Hospital) were treated with either interferon beta or glatiramer acetate as their initial treatment for MS. RESULTS: The probability of failing initial treatment within 3 years was 30%. Clinical activity, defined as relapses and/or progression in disability, determined treatment failure in 35.7% (n=10) of nonresponders. New T2 hyperintense or gadolinium-enhancing lesions on MRI was used to define treatment failure in 28.6% (n=8) and new MRI lesions were used in combination with clinical activity in 35.7% (n=10). Treatment failures had a higher T2 hyperintense lesion volume (p=0.015) and number of gadolinium-enhancing lesions (p=0.0001) on the enrollment MRI than responders. CONCLUSIONS: These observations demonstrate that treating physicians use both clinical and MRI parameters to define a response to treatment and initiation of a treatment change and that baseline MRI identified those with increased risk of treatment failure.


Subject(s)
Immunologic Factors/therapeutic use , Interferon-beta/therapeutic use , Multiple Sclerosis, Relapsing-Remitting/drug therapy , Peptides/therapeutic use , Adult , Contrast Media , Disease Progression , Female , Follow-Up Studies , Gadolinium , Glatiramer Acetate , Humans , Incidence , Interferon beta-1a , Interferon beta-1b , Magnetic Resonance Imaging , Male , Middle Aged , Multiple Sclerosis, Relapsing-Remitting/pathology , Prospective Studies , Risk Factors , Treatment Failure , Young Adult
9.
Fungal Genet Biol ; 44(10): 1035-49, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17600737

ABSTRACT

Towards the goal of disrupting all genes in the genome of Magnaporthe oryzae and identifying their function, a collection of >55,000 random insertion lines of M. oryzae strain 70-15 were generated. All strains were screened to identify genes involved in growth rate, conidiation, pigmentation, auxotrophy, and pathogenicity. Here, we provide a description of the high throughput transformation and analysis pipeline used to create our library. Transformed lines were generated either by CaCl(2)/PEG treatment of protoplasts with DNA or by Agrobacterium tumefaciens-mediated transformation (ATMT). We describe the optimization of both approaches and compare their efficiency. ATMT was found to be a more reproducible method, resulting in predominantly single copy insertions, and its efficiency was high with up to 0.3% of conidia being transformed. The phenotypic data is accessible via a public database called MGOS and all strains are publicly available. This represents the most comprehensive insertional mutagenesis analysis of a fungal pathogen.


Subject(s)
Magnaporthe/genetics , Mutagenesis, Insertional/methods , 3' Flanking Region , 5' Flanking Region , Agrobacterium tumefaciens/genetics , Phenotype , Protoplasts , Transformation, Genetic
10.
Neurology ; 68(24): 2059-65, 2007 Jun 12.
Article in English | MEDLINE | ID: mdl-17562826

ABSTRACT

OBJECTIVE: To develop covariate specific short-term disability curves to demonstrate the probability of progressing by Expanded Disability Status Scale (EDSS) at semiannual visits. METHODS: Semiannual EDSS scores were prospectively collected in 218 relapsing-remitting (RR) and clinically isolated syndrome (CIS) patients as part of the Comprehensive Longitudinal Investigation of Multiple Sclerosis at the Brigham and Women's Hospital (CLIMB) study. Baseline brain parenchymal fraction (BPF) and T2 lesion volume were available on 205 patients. A partial proportional odds model determined the influence of covariates on the change in EDSS score at subsequent visits. A discrete second order Markov transitional model was fit and generated a probability matrix for each subject; the 6-month probabilities of EDSS change were graphically represented. RESULTS: The univariate analysis demonstrated the lowest baseline BPF quartile (OR 1.99; p = 0.0203) and the highest T2 lesion volume quartile (OR 2.19; p = 0.0130) were associated with progression in EDSS. Covariate specific disability curves demonstrated the effect of BPF and T2 lesion volume on short-term progression. In subjects with a 6-month EDSS of 2, the probability of a sustained progression of an EDSS of 3 within 3 years was 0.277 for a subject with low BPF and a high T2 lesion volume vs 0.055 for a subject with high BPF and a low T2 lesion volume. CONCLUSIONS: Markov transitional models allow for the comparison of covariate specific short-term disability changes among groups of patients with multiple sclerosis.


Subject(s)
Brain/pathology , Disability Evaluation , Multiple Sclerosis/diagnosis , Multiple Sclerosis/epidemiology , Adult , Brain/physiopathology , Disease Progression , Female , Humans , Longitudinal Studies , Magnetic Resonance Imaging , Male , Markov Chains , Middle Aged , Models, Statistical , Predictive Value of Tests , Prognosis , Prospective Studies , Time Factors
11.
Eukaryot Cell ; 6(7): 1189-99, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17513566

ABSTRACT

Coccidioides species, the fungi responsible for the valley fever disease, are known to reproduce asexually through the production of arthroconidia that are the infectious propagules. The possible role of sexual reproduction in the survival and dispersal of these pathogens is unexplored. To determine the potential for mating of Coccidioides, we analyzed genome sequences and identified mating type loci characteristic of heterothallic ascomycetes. Coccidioides strains contain either a MAT1-1 or a MAT1-2 idiomorph, which is 8.1 or 9 kb in length, respectively, the longest reported for any ascomycete species. These idiomorphs contain four or five genes, respectively, more than are present in the MAT loci of most ascomycetes. Along with their cDNA structures, we determined that all genes in the MAT loci are transcribed. Two genes frequently found in common sequences flanking MAT idiomorphs, APN2 and COX13, are within the MAT loci in Coccidioides, but the MAT1-1 and MAT1-2 copies have diverged dramatically from each other. Data indicate that the acquisition of these genes in the MAT loci occurred prior to the separation of Coccidioides from Uncinocarpus reesii. An analysis of 436 Coccidioides isolates from patients and the environment indicates that in both Coccidioides immitis and C. posadasii, there is a 1:1 distribution of MAT loci, as would be expected for sexually reproducing species. In addition, an analysis of isolates obtained from 11 soil samples demonstrated that at three sampling sites, strains of both mating types were present, indicating that compatible strains were in close proximity in the environment.


Subject(s)
Coccidioides , Genes, Mating Type, Fungal , Genome, Fungal , Reproduction , Coccidioides/genetics , Coccidioides/physiology , DNA-(Apurinic or Apyrimidinic Site) Lyase/classification , DNA-(Apurinic or Apyrimidinic Site) Lyase/genetics , DNA-(Apurinic or Apyrimidinic Site) Lyase/metabolism , Fungal Proteins/classification , Fungal Proteins/genetics , Fungal Proteins/metabolism , Membrane Proteins/classification , Membrane Proteins/genetics , Membrane Proteins/metabolism , Nuclear Proteins/classification , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Phylogeny , Transcription, Genetic
12.
Clin Exp Immunol ; 149(2): 235-42, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17488294

ABSTRACT

Multiple sclerosis (MS) is a demyelinating disease characterized by an unpredictable clinical course with intermittent relapses that lead over time to significant neurological disability. Clinical and radiological variables are limited in the ability to predict disease course. Peripheral blood genome scale analyses were used to characterize MS patients with different disease types, but not for prediction of outcome. Using complementary-DNA microarrays we studied peripheral-blood gene expression patterns in 53 relapsing-remitting MS patients. Patients were classified into good, intermediate and poor clinical outcome established after 2-year follow-up. A training set of 26 samples was used to identify clinical outcome differentiating gene-expression signature. Supervised learning and feature selection algorithms were applied to identify a predictive signature that was validated in an independent group of 27 patients. Key genes within the predictive signature were confirmed by quantitative reverse transcription-polymerase chain reaction in an additional 10 patients. The analysis identified 431 differentiating genes between patients with good and poor clinical outcome (change in neurological disability by the expanded disability status scale was -0.33 +/- 0.24 and 1.6 +/- 0.35, P = 0.0002, total number of relapses were 0 and 1.80 +/- 0.35, P = 0.00009, respectively). An optimal set of 29 genes was depicted as a clinical outcome predictive gene expression signature and classified appropriately 88.9% of patients. This predictive signature was enriched by genes related biologically to zinc-ion binding and cytokine activity regulation pathways involved in inflammation and apoptosis. Our findings provide a basis for monitoring patients by prediction of disease outcome and can be incorporated into clinical decision-making in relapsing-remitting MS.


Subject(s)
Cytokines/genetics , Gene Expression Regulation , Multiple Sclerosis, Relapsing-Remitting/genetics , Zinc/metabolism , Adult , Algorithms , Cytokines/metabolism , Disease Progression , Female , Follow-Up Studies , Gene Expression Profiling/methods , Humans , Male , Middle Aged , Multiple Sclerosis, Relapsing-Remitting/diagnosis , Multiple Sclerosis, Relapsing-Remitting/metabolism , Oligonucleotide Array Sequence Analysis/methods , Prognosis , Reverse Transcriptase Polymerase Chain Reaction/methods , Severity of Illness Index , Signal Transduction/genetics
13.
Lupus ; 15(7): 451-6, 2006.
Article in English | MEDLINE | ID: mdl-16898181

ABSTRACT

In a single assay, gene microarrays generate tens of thousands of measurements for the relative levels of messenger RNA expression, and thus hold promise to uncover the regulation of transcriptional responses behind clinical phenotypes of various diseases. Systemic lupus erythematosus (SLE) offers a unique opportunity to study gene expression both systemically and organ specific, as the tissues involved and specifically peripheral blood cells are readily accessible for molecular analysis. In the current review we highlight the current knowledge related to gene microarray in SLE. We approached the following questions: 1) Can gene microarray technology be used to translate molecular profiles into meaningful and applicable clinical information? 2) Does the assessment of differential gene expression provide specific signatures that may contribute to diagnostic and prognostic markers of SLE? 3) Can clinicians be helped in monitoring disease activity by identification of drug response gene profile? 4) Does evaluation of differential gene expression provide clues to detect previously unrecognized genes associated with the disease? It is evident that though not all questions can be currently answered appropriately, gene expression studies in SLE have important implications and will not only be beneficial for SLE patients, but will also lead to a better understanding of other autoimmune inflammatory diseases, thereby leading to novel diagnostic and therapeutic strategies in autoimmunity.


Subject(s)
Gene Expression/genetics , Lupus Erythematosus, Systemic/genetics , Oligonucleotide Array Sequence Analysis/methods , Autoimmunity/genetics , Gene Expression Profiling/methods , Humans , Lupus Erythematosus, Systemic/diagnosis , Lupus Erythematosus, Systemic/immunology , Reproducibility of Results
14.
Fungal Genet Biol ; 43(11): 775-88, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16857399

ABSTRACT

Coccidioides posadasii is a dimorphic fungal pathogen of humans and other mammals. The switch between saprobic and parasitic growth involves synthesis of new cell walls of which chitin is a significant component. To determine whether particular subsets of chitin synthases (CHSes) are responsible for production of chitin at different stages of differentiation, we have isolated six CHS genes from this fungus. They correspond, together with another reported CHS gene, to single members of the seven defined classes of chitin synthases (classes I-VII). Using Real-Time RT-PCR we show their pattern of expression during morphogenesis. CpCHS2, CpCHS3, and CpCHS6 are preferentially expressed during the saprobic phase, while CpCHS1 and CpCHS4 are more highly expressed during the parasitic phase. CpCHS5 and CpCHS7 expression is similar in both saprobic and parasitic phases. Because C. posadasii contains single members of the seven classes of CHSes found in fungi, it is a good model to investigate the putatively different roles of these genes in fungal growth and differentiation.


Subject(s)
Chitin Synthase/genetics , Coccidioides/genetics , Fungal Proteins/genetics , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Fungal , Animals , Base Sequence , Chitin Synthase/classification , Coccidioides/enzymology , Coccidioides/growth & development , Coccidioides/pathogenicity , Fungal Proteins/biosynthesis , Gene Expression Profiling/methods , Gene Expression Regulation, Enzymologic/genetics , Gene Expression Regulation, Fungal/genetics , Humans , Molecular Sequence Data , Reverse Transcriptase Polymerase Chain Reaction/methods
15.
Stat Med ; 24(12): 1933-45, 2005 Jun 30.
Article in English | MEDLINE | ID: mdl-15806618

ABSTRACT

In the last decade, many statistics have been suggested to evaluate the performance of survival models. These statistics evaluate the overall performance of a model ignoring possible variability in performance over time. Using an extension of measures used in binary regression, we propose a graphical method to depict the performance of a survival model over time. The method provides estimates of performance at specific time points and can be used as an informal test for detecting time varying effects of covariates in the Cox model framework. The method is illustrated on real and simulated data using Cox proportional hazard model and rank statistics.


Subject(s)
Models, Statistical , Survival Analysis , Humans , Israel , Proportional Hazards Models , ROC Curve , Reproducibility of Results
16.
J Hosp Infect ; 59(4): 331-42, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15749322

ABSTRACT

Critically ill patients, eligible for admission into intensive care units (ICUs), are often hospitalized in other wards due to a lack of ICU beds. Differences in morbidity between patients managed in ICUs and elsewhere are unknown, specifically the morbidity related to hospital-acquired infection. Patients fitting ICU admission criteria were identified by screening five entire hospitals on four separate days. Hospital infections within a 30-day follow-up period were compared in ICU patients and in patients on other wards using Kaplan-Meier curves. Residual differences in the patients' case mix between ICUs and other wards were adjusted for utilizing multivariate Cox models. Of 13415 patients screened, 668 were critically ill. The overall infection rates (per 100 patient-days) were 1.2 for bloodstream infection (BSI) and 1.9 for urinary tract infection (UTI). The adjusted hazard ratios in ICU patients compared with patients on regular wards were 3.1 (P<0.001) for BSI and 2.5 (P<0.001) for UTI. This increased risk persisted even after adjusting for the disparity in the number of cultures sent from ICUs compared with ordinary wards. No interdepartmental differences were found in the rates of pneumonia, surgical wound infections and other infections. Minimizing the differences between characteristics of patients hospitalized in ICUs and in other wards, and controlling for the higher frequency of cultures sent from ICUs did not eliminate the increased risk of BSI and UTI associated with admission into ICUs.


Subject(s)
Bacteremia/mortality , Cross Infection/mortality , Intensive Care Units/statistics & numerical data , Patient Admission , Risk Assessment , Urinary Tract Infections/mortality , Aged , Bacteremia/etiology , Bacteremia/prevention & control , Critical Illness/mortality , Cross Infection/etiology , Cross Infection/prevention & control , Female , Hospital Mortality , Humans , Infection Control , Israel/epidemiology , Male , Middle Aged , Patients' Rooms/statistics & numerical data , Proportional Hazards Models , Risk Factors , Urinary Tract Infections/etiology , Urinary Tract Infections/prevention & control
17.
Eukaryot Cell ; 4(1): 111-20, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15643067

ABSTRACT

1,3-beta-Glucan synthase is responsible for the synthesis of beta-glucan, an essential cell wall structural component in most fungi. We sought to determine whether Coccidioides posadasii possesses genes homologous to known fungal FKS genes that encode the catalytic subunit of 1,3-beta-glucan synthase. A single gene, designated FKS1, was identified, and examination of its predicted protein product showed a high degree of conservation with Fks proteins from other filamentous fungi. FKS1 is expressed at similar levels in mycelia and early spherulating cultures, and expression decreases as the spherules mature. We used Agrobacterium-mediated transformation to create strains that harbor DeltaFKS1::hygB, a null allele of FKS1, and hypothesize that Fks1p function is essential, due to our inability to purify this allele away from a complementing wild-type FKS1 allele in a heterokaryotic strain. The heterokaryon appears normal with respect to growth rate and arthroconidium production; however, microscopic examination of strains with DeltaFKS1::hygB alleles revealed abnormal swelling of hyphal elements.


Subject(s)
Coccidioides/enzymology , Coccidioides/physiology , Glucosyltransferases/genetics , Glucosyltransferases/physiology , Alleles , Amino Acid Sequence , Blotting, Southern , Catalytic Domain , Cell Nucleus/metabolism , Cell Proliferation , Cell Survival , Cell Wall/metabolism , Cells, Cultured , Fungal Proteins/metabolism , Gene Deletion , Gene Library , Genes, Fungal , Mitosis , Models, Genetic , Molecular Sequence Data , Plasmids/metabolism , RNA/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Rhizobium/genetics , Sequence Homology, Amino Acid , Time Factors
18.
Clin Dev Immunol ; 11(3-4): 299-305, 2004.
Article in English | MEDLINE | ID: mdl-15559377

ABSTRACT

Multiple sclerosis (MS) is a central nervous system disease in which activated autoreactive T-cells invade the blood brain barrier and initiate an inflammatory response that leads to myelin destruction and axonal loss. The etiology of MS, as well as the mechanisms associated with its unexpected onset, the unpredictable clinical course spanning decades, and the different rates of progression leading to disability over time, remains an enigma. We have applied gene expression microarrays technology in peripheral blood mononuclear cells (PBMC) to better understand MS pathogenesis and better target treatment approaches. A signature of 535 genes were found to distinguish immunomodulatory treatment effects between 13 treated and 13 untreated MS patients. In addition, the expression pattern of 1109 gene transcripts that were previously reported to significantly differentiate between MS patients and healthy subjects were further analyzed to study the effect of cytokine-related pathways on disease pathogenesis. When relative gene expression for 26 MS patients was compared to 18 healthy controls, 30 genes related to various cytokine-associated pathways were identified. These genes belong to a variety of families such as interleukins, small inducible cytokine subfamily and tumor necrosis factor ligand and receptor. Further analysis disclosed seven cytokine-associated genes within the immunomodulatory treatment signature, and two cytokine-associated genes SCYA4 (small inducible cytokine A4) and FCAR (Fc fragment of IgA, CD89) that were common to both the MS gene expression signature and the immunomodulatory treatment gene expression signature. Our results indicate that cytokine-associated genes are involved in various pathogenic pathways in MS and also related to immunomodulatory treatment effects.


Subject(s)
Autoimmunity , Multiple Sclerosis, Relapsing-Remitting/genetics , Multiple Sclerosis, Relapsing-Remitting/immunology , Apoptosis , Autoimmunity/genetics , Case-Control Studies , Cell Movement , Cytokines/genetics , Cytokines/metabolism , Demyelinating Diseases , Gene Expression Profiling , Humans , Immunologic Factors/therapeutic use , Leukocytes, Mononuclear/immunology , Lymphocyte Activation , Models, Immunological , Multiple Sclerosis, Relapsing-Remitting/therapy , Oligonucleotide Array Sequence Analysis , T-Lymphocytes/immunology
19.
Clin Immunol ; 113(2): 155-60, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15451472

ABSTRACT

Myelin autoreactive T cells are involved in the pathogenesis of multiple sclerosis (MS) and lead to propagation of the disease. We evaluated the efficacy of T cell vaccination (TCV) therapy for patients with aggressive relapsing-remitting MS who failed to respond to immunomodulatory treatments. Twenty nonresponders relapsing-remitting MS patients were immunized with autologous attenuated T cell lines after activation with synthetic myelin basic protein (MBP) and myelin oligodendrocyte glycoprotein (MOG) encephalitogenic peptides. Each patient received three vaccinations in 6- to 8-week intervals. Annual relapse rate decreased from 2.6 to 1.1, P = 0.026. Neurological disability stabilized as compared with the 2- and 1-year pretreatment progression rates. Significant reduction in the number and volume of active lesions, as well as reduction in T2 lesion burden, was demonstrated by quantitative MRI analysis. No serious adverse events were observed. Our findings suggest that TCV has beneficial clinical effects in MS patients who, in spite of immunomodulatory treatments, continue to deteriorate. TCV could serve as a potential alternative therapy for this subgroup of nonresponders patients.


Subject(s)
Immunotherapy, Active , Multiple Sclerosis, Relapsing-Remitting/immunology , Multiple Sclerosis, Relapsing-Remitting/therapy , T-Lymphocytes/transplantation , Adult , Brain/pathology , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Multiple Sclerosis, Relapsing-Remitting/pathology , Myelin Basic Protein/immunology , Myelin Proteins , Myelin-Associated Glycoprotein/immunology , Myelin-Oligodendrocyte Glycoprotein , T-Lymphocytes/immunology , Treatment Outcome
20.
Clin Exp Immunol ; 138(1): 164-70, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15373920

ABSTRACT

Autoimmune diseases are either tissue-specific like multiple sclerosis (MS) or multisystemic like systemic lupus erythematosus (SLE), although clinically both exhibit common features. To gain insight into the properties of the genes involved in each disease we have investigated the gene expression signature of peripheral blood mononuclear cells (PBMC) in MS and SLE in comparison to healthy subjects. Total RNA was purified, hybridized to Genechip array and analysed in 36 subjects (13 relapsing-remitting MS patients, five SLE patients and 18 age-matched healthy subjects that served as controls). Additional blood samples from 15 relapsing-remitting MS patients, 8 SLE patients and 10 healthy subjects were used for confirmation of microarray gene expression findings by ELISA and RT-PCR. MS and SLE patients demonstrated a common gene expression autoimmune signature of 541 genes which differentiated them from healthy subjects. The autoimmune signature included genes that encode proteins involved in apoptosis, cell cycle, inflammation and regulation of matrix metalloproteinase pathways. Specifically, decreased TIMP1 gene expression in the autoimmunity signature suggests increased MMP activity in target tissues as a result of the lack of feedback mechanism. An additional different disease specific signature identified the gene expression pattern for MS (1031 genes), mainly associated with over-expression of adhesion molecules and down-expression of heat shock proteins; the SLE specific signature (1146 genes) mainly involved DNA damage/repair pathways that result in production of nuclear autoantibodies. These results provide insights into the genetic pathways underlying autoimmune diseases, and identify specific disease-associated signatures that may enable targetted disease-related specific therapies to be developed.


Subject(s)
Gene Expression/immunology , Lupus Erythematosus, Systemic/immunology , Multiple Sclerosis/immunology , Adult , Antibody Formation/genetics , Antibody Formation/immunology , Apoptosis/genetics , Apoptosis/immunology , Autoimmunity/genetics , Autoimmunity/immunology , Cell Division/genetics , Cell Division/immunology , Female , Gene Expression/genetics , Humans , Inflammation/genetics , Inflammation/immunology , Leukocytes, Mononuclear/immunology , Lupus Erythematosus, Systemic/genetics , Male , Matrix Metalloproteinases/genetics , Matrix Metalloproteinases/immunology , Multiple Sclerosis/genetics , Oligonucleotide Array Sequence Analysis/methods
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