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1.
Microbiol Spectr ; 10(2): e0256421, 2022 04 27.
Article in English | MEDLINE | ID: mdl-35234489

ABSTRACT

Next-generation sequencing (NGS) is a powerful tool for detecting and investigating viral pathogens; however, analysis and management of the enormous amounts of data generated from these technologies remains a challenge. Here, we present VPipe (the Viral NGS Analysis Pipeline and Data Management System), an automated bioinformatics pipeline optimized for whole-genome assembly of viral sequences and identification of diverse species. VPipe automates the data quality control, assembly, and contig identification steps typically performed when analyzing NGS data. Users access the pipeline through a secure web-based portal, which provides an easy-to-use interface with advanced search capabilities for reviewing results. In addition, VPipe provides a centralized system for storing and analyzing NGS data, eliminating common bottlenecks in bioinformatics analyses for public health laboratories with limited on-site computational infrastructure. The performance of VPipe was validated through the analysis of publicly available NGS data sets for viral pathogens, generating high-quality assemblies for 12 data sets. VPipe also generated assemblies with greater contiguity than similar pipelines for 41 human respiratory syncytial virus isolates and 23 SARS-CoV-2 specimens. IMPORTANCE Computational infrastructure and bioinformatics analysis are bottlenecks in the application of NGS to viral pathogens. As of September 2021, VPipe has been used by the U.S. Centers for Disease Control and Prevention (CDC) and 12 state public health laboratories to characterize >17,500 and 1,500 clinical specimens and isolates, respectively. VPipe automates genome assembly for a wide range of viruses, including high-consequence pathogens such as SARS-CoV-2. Such automated functionality expedites public health responses to viral outbreaks and pathogen surveillance.


Subject(s)
COVID-19 , Viruses , Computational Biology/methods , High-Throughput Nucleotide Sequencing/methods , Humans , SARS-CoV-2/genetics , Viruses/genetics
2.
Front Genet ; 11: 601870, 2020.
Article in English | MEDLINE | ID: mdl-33324449

ABSTRACT

Effective laboratory-based surveillance and public health response to bacterial meningitis depends on timely characterization of bacterial meningitis pathogens. Traditionally, characterizing bacterial meningitis pathogens such as Neisseria meningitidis (Nm) and Haemophilus influenzae (Hi) required several biochemical and molecular tests. Whole genome sequencing (WGS) has enabled the development of pipelines capable of characterizing the given pathogen with equivalent results to many of the traditional tests. Here, we present the Bacterial Meningitis Genomic Analysis Platform (BMGAP): a secure, web-accessible informatics platform that facilitates automated analysis of WGS data in public health laboratories. BMGAP is a pipeline comprised of several components, including both widely used, open-source third-party software and customized analysis modules for the specific target pathogens. BMGAP performs de novo draft genome assembly and identifies the bacterial species by whole-genome comparisons against a curated reference collection of 17 focal species including Nm, Hi, and other closely related species. Genomes identified as Nm or Hi undergo multi-locus sequence typing (MLST) and capsule characterization. Further typing information is captured from Nm genomes, such as peptides for the vaccine antigens FHbp, NadA, and NhbA. Assembled genomes are retained in the BMGAP database, serving as a repository for genomic comparisons. BMGAP's species identification and capsule characterization modules were validated using PCR and slide agglutination from 446 bacterial invasive isolates (273 Nm from nine different serogroups, 150 Hi from seven different serotypes, and 23 from nine other species) collected from 2017 to 2019 through surveillance programs. Among the validation isolates, BMGAP correctly identified the species for all 440 isolates (100% sensitivity and specificity) and accurately characterized all Nm serogroups (99% sensitivity and 98% specificity) and Hi serotypes (100% sensitivity and specificity). BMGAP provides an automated, multi-species analysis pipeline that can be extended to include additional analysis modules as needed. This provides easy-to-interpret and validated Nm and Hi genome analysis capacity to public health laboratories and collaborators. As the BMGAP database accumulates more genomic data, it grows as a valuable resource for rapid comparative genomic analyses during outbreak investigations.

3.
BMC Genomics ; 20(1): 733, 2019 Oct 12.
Article in English | MEDLINE | ID: mdl-31606037

ABSTRACT

BACKGROUND: Haemophilus influenzae (Hi) can cause invasive diseases such as meningitis, pneumonia, or sepsis. Typeable Hi includes six serotypes (a through f), each expressing a unique capsular polysaccharide. The capsule, encoded by the genes within the capsule locus, is a major virulence factor of typeable Hi. Non-typeable (NTHi) does not express capsule and is associated with invasive and non-invasive diseases. METHODS: A total of 395 typeable and 293 NTHi isolates were characterized by whole genome sequencing (WGS). Phylogenetic analysis and multilocus sequence typing were used to characterize the overall genetic diversity. Pair-wise comparisons were used to evaluate the capsule loci. A WGS serotyping method was developed to predict the Hi serotype. WGS serotyping results were compared to slide agglutination (SAST) or real-time PCR (rt-PCR) serotyping. RESULTS: Isolates of each Hi serotype clustered into one or two subclades, with each subclade being associated with a distinct sequence type (ST). NTHi isolates were genetically diverse, with seven subclades and 125 STs being detected. Regions I and III of the capsule locus were conserved among the six serotypes (≥82% nucleotide identity). In contrast, genes in Region II were less conserved, with only six gene pairs from all serotypes showing ≥56% nucleotide identity. The WGS serotyping method was 99.9% concordant with SAST and 100% concordant with rt-PCR in determining the Hi serotype. CONCLUSIONS: Genomic analysis revealed a higher degree of genetic diversity among NTHi compared to typeable Hi. The WGS serotyping method accurately predicted the Hi capsule type and can serve as an alternative method for Hi serotyping.


Subject(s)
Bacterial Capsules/genetics , Genomics/methods , Haemophilus influenzae/classification , Polysaccharides, Bacterial/genetics , Bacterial Typing Techniques , Genetic Variation , Haemophilus influenzae/genetics , Haemophilus influenzae/isolation & purification , Humans , Multilocus Sequence Typing , Phylogeny , Serotyping , Virulence Factors/genetics , Whole Genome Sequencing
4.
J Clin Microbiol ; 57(3)2019 03.
Article in English | MEDLINE | ID: mdl-30567750

ABSTRACT

Invasive meningococcal disease is mainly caused by Neisseria meningitidis serogroups A, B, C, X, W, and Y. The serogroup is typically determined by slide agglutination serogrouping (SASG) and real-time PCR (RT-PCR). We describe a whole-genome sequencing (WGS)-based method to characterize the capsule polysaccharide synthesis (cps) locus, classify N. meningitidis serogroups, and identify mechanisms for nongroupability using 453 isolates from a global strain collection. We identified novel genomic organizations within functional cps loci, consisting of insertion sequence (IS) elements in unique positions that did not disrupt the coding sequence. Genetic mutations (partial gene deletion, missing genes, IS insertion, internal stop, and phase-variable off) that led to nongroupability were identified. The results of WGS and SASG were in 91% to 100% agreement for all serogroups, while the results of WGS and RT-PCR showed 99% to 100% agreement. Among isolates determined to be nongroupable by WGS (31 of 453), the results of all three methods agreed 100% for those without a capsule polymerase gene. However, 61% (WGS versus SASG) and 36% (WGS versus RT-PCR) agreements were observed for the isolates, particularly those with phase variations or internal stops in cps loci, which warrant further characterization by additional tests. Our WGS-based serogrouping method provides comprehensive characterization of the N. meningitidis capsule, which is critical for meningococcal surveillance and outbreak investigations.


Subject(s)
Bacterial Capsules/genetics , Genome, Bacterial , Genome-Wide Association Study , Meningococcal Infections/microbiology , Neisseria meningitidis/genetics , Serogroup , Bacterial Capsules/metabolism , Humans , Phylogeny
5.
Nucleic Acids Res ; 44(7): e69, 2016 Apr 20.
Article in English | MEDLINE | ID: mdl-26826710

ABSTRACT

The identification of genes with specific patterns of change (e.g. down-regulated and methylated) as phenotype drivers or samples with similar profiles for a given gene set as drivers of clinical outcome, requires the integration of several genomic data types for which an 'integrate by intersection' (IBI) approach is often applied. In this approach, results from separate analyses of each data type are intersected, which has the limitation of a smaller intersection with more data types. We introduce a new method, GISPA (Gene Integrated Set Profile Analysis) for integrated genomic analysis and its variation, SISPA (Sample Integrated Set Profile Analysis) for defining respective genes and samples with the context of similar, a priori specified molecular profiles. With GISPA, the user defines a molecular profile that is compared among several classes and obtains ranked gene sets that satisfy the profile as drivers of each class. With SISPA, the user defines a gene set that satisfies a profile and obtains sample groups of profile activity. Our results from applying GISPA to human multiple myeloma (MM) cell lines contained genes of known profiles and importance, along with several novel targets, and their further SISPA application to MM coMMpass trial data showed clinical relevance.


Subject(s)
Genes, Neoplasm , Genomics/methods , Cell Line, Tumor , DNA Methylation , Gene Expression Profiling , Humans , Multiple Myeloma/genetics , Multiple Myeloma/mortality , Mutation , Prognosis
6.
Cancer Genet ; 208(11): 525-36, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26454669

ABSTRACT

Cytogenomic microarray analysis (CMA) offers high resolution, genome-wide copy number information and is widely used in clinical laboratories for diagnosis of constitutional abnormalities. The Cancer Genomics Consortium (CGC) conducted a multiplatform, multicenter clinical validation project to compare the reliability and inter- and intralaboratory reproducibility of this technology for clinical oncology applications. Four specimen types were processed on three different microarray platforms-from Affymetrix, Agilent, and Illumina. Each microarray platform was employed at two independent test sites. The results were compared in a blinded manner with current standard methods, including karyotype, FISH, or morphology. Twenty-nine chronic lymphocytic leukemia blood, 34 myelodysplastic syndrome bone marrow, and 30 fresh frozen renal epithelial tumor samples were assessed by all six laboratories. Thirty formalin fixed paraffin embedded renal tumor samples were analyzed at the Affymetrix and Agilent test sites only. All study samples were initial diagnostic samples. Array data were analyzed at each participating site and were submitted to caArray for central analysis. Laboratory interpretive results were submitted to the central analysis team for comparison with the standard-of-care assays and for calculation of intraplatform reproducibility and cross-platform concordance. The results demonstrated that the three microarray platforms 1) detect clinically actionable genomic changes in cancer compatible to standard-of-care methods; 2) further define cytogenetic aberrations; 3) identify submicroscopic alterations and loss of heterozygosity (LOH); and 4) yield consistent results within and between laboratories. Based on this study, the CGC concludes that CMA is a sensitive and reliable technique for copy number and LOH assessment that may be used for clinical oncology genomic analysis.


Subject(s)
Comparative Genomic Hybridization/methods , Cytogenetic Analysis/methods , Neoplasms/diagnosis , Oligonucleotide Array Sequence Analysis/methods , Chromosome Aberrations , Gene Dosage , Humans , In Situ Hybridization, Fluorescence , Karyotype , Kidney Neoplasms/diagnosis , Kidney Neoplasms/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Loss of Heterozygosity , Myelodysplastic Syndromes/diagnosis , Myelodysplastic Syndromes/genetics , Neoplasms/genetics , Neoplasms, Glandular and Epithelial/diagnosis , Neoplasms, Glandular and Epithelial/genetics , Reproducibility of Results , Standard of Care
7.
Radiat Res ; 184(3): 249-58, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26284422

ABSTRACT

Cell populations that have been exposed to high-charge and energy (HZE) particle radiation, and then challenged by expression of a rare-cutting nuclease, show an increased frequency of deletions and translocations originating at the enzyme cut sites. Here, we examine whether this effect also occurs in nonirradiated cells that have been co-cultured with irradiated cells. Human cells were irradiated with 0.3-1.0 Gy of either 600 MeV/u (56)Fe or 1,000 MeV/u (48)Ti ions or with 0.3-3.0 Gy of 320 kV X rays. These were co-cultured with I-SceI-expressing reporter cells at intervals up to 21 days postirradiation. Co-culture with HZE-irradiated cells led to an increase in the frequency of I-SceI-stimulated translocations and deletions in the nonirradiated cells. The effect size was similar to that seen previously in directly irradiated populations (maximum effect in bystander cells of 1.7- to 4-fold depending on ion and end point). The effect was not observed when X-ray-irradiated cells were co-cultured with nonirradiated cells, but was correlated with an increase in γ-H2AX foci-positive cells in the nonirradiated population, suggesting the presence of genomic stress. Transcriptional profiling of a directly irradiated cell population showed that many genes for cytokines and other secretory proteins were persistently upregulated, but their induction was not well correlated with functional effects on repair in co-cultured cells, suggesting that this transcriptional response alone is not sufficient to evoke the effect. The finding that HZE-irradiated cells influence the DNA double-strand break repair fidelity in their nonirradiated neighbors has implications for risk in the space radiation environment.


Subject(s)
Cosmic Radiation , DNA Breaks, Double-Stranded/radiation effects , Bystander Effect , Cell Line, Tumor , Coculture Techniques , DNA Repair , Gene Expression Profiling , Humans , Mutation
8.
Head Neck Pathol ; 9(2): 223-35, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25236499

ABSTRACT

The role of molecular methods in the diagnosis of head and neck cancer is rapidly evolving and holds great potential for improving outcomes for all patients who suffer from this diverse group of malignancies . However, there is considerable debate as to the best clinical approaches, particularly for Next Generation Sequencing (NGS). The choices of NGS methods such as whole exome, whole genome, whole transcriptomes (RNA-Seq) or multiple gene resequencing panels, each have strengths and weakness based on data quality, the size of the data, the turnaround time for data analysis, and clinical actionability. There have also been a variety of gene expression signatures established from microarray studies that correlate with relapse and response to treatment, but none of these methods have been implemented as standard of care for oropharyngeal squamous cell carcinoma (OPSCC). Because many genomic methodologies are still far from the capabilities of most clinical laboratories, we chose to explore the use of a combination of off the shelf targeted mutation analysis and gene expression analysis methods to complement standard anatomical pathology methods. Specifically, we have used the Ion Torrent AmpliSeq cancer panel in combination with the NanoString nCounter Human Cancer Reference Kit on 8 formalin-fixed paraffin embedded (FFPE) OPSCC tumor specimens, (4) HPV-positive and (4) HPV-negative. Differential expression analysis between HPV-positive and negative groups showed that expression of several genes was highly likely to correlate with HPV status. For example, WNT1, PDGFA and OGG1 were all over-expressed in the positive group. Our results show the utility of these methods with routine FFPE clinical specimens to identify potential therapeutic targets which could be readily applied in a clinical trial setting for clinical laboratories lacking the instrumentation or bioinformatics infrastructure to support comprehensive genomics workflows. To the best of our knowledge, these preliminary experiments are among the earliest to combine both mutational and gene expression profiles using Ion Torrent and NanoString technologies. This reports serves as a proof of principle methodology in OPSCC.


Subject(s)
Biomarkers, Tumor/genetics , Carcinoma, Squamous Cell/genetics , Gene Expression Profiling/methods , Immunohistochemistry/methods , Mutation/genetics , Oropharyngeal Neoplasms/genetics , Transcription, Genetic/genetics , Antineoplastic Agents/therapeutic use , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/virology , DNA Glycosylases/genetics , DNA Mutational Analysis/methods , Gene Expression Regulation, Neoplastic , High-Throughput Nucleotide Sequencing/methods , Humans , Oropharyngeal Neoplasms/drug therapy , Oropharyngeal Neoplasms/virology , Papillomaviridae , Pilot Projects , Platelet-Derived Growth Factor/genetics , Wnt1 Protein/genetics
9.
Cancer Inform ; 13(Suppl 2): 49-53, 2014.
Article in English | MEDLINE | ID: mdl-25288879

ABSTRACT

We present a pipeline to perform integrative analysis of mate-pair (MP) and paired-end (PE) genomic DNA sequencing data. Our pipeline detects structural variations (SVs) by taking aligned sequencing read pairs as input and classifying these reads into properly paired and discordantly paired categories based on their orientation and inferred insert sizes. Recurrent SV was identified from the discordant read pairs. Our pipeline takes into account genomic annotation and genome repetitive element information to increase detection specificity. Application of our pipeline to whole-genome MP and PE sequencing data from three multiple myeloma cell lines (KMS11, MM.1S, and RPMI8226) recovered known SVs, such as heterozygous TRAF3 deletion, as well as a novel experimentally validated SPI1 - ZNF287 inter-chromosomal rearrangement in the RPMI8226 cell line.

10.
Cancer Med ; 3(6): 1579-94, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25124282

ABSTRACT

Poly (ADP) ribose polymerase (PARP) plays a key role in DNA repair and is highly expressed in small cell lung cancer (SCLC). We investigated the therapeutic impact of PARP inhibition in SCLC. In vitro cytotoxicity of veliparib, cisplatin, carboplatin, and etoposide singly and combined was determined by MTS in 9 SCLC cell lines (H69, H128, H146, H526, H187, H209, DMS53, DMS153, and DMS114). Subcutaneous xenografts in athymic nu/nu mice of H146 and H128 cells with relatively high and low platinum sensitivity, respectively, were employed for in vivo testing. Mechanisms of differential sensitivity of SCLC cell lines to PARP inhibition were investigated by comparing protein and gene expression profiles of the platinum sensitive and the less sensitive cell lines. Veliparib showed limited single-agent cytotoxicity but selectively potentiated (≥ 50% reduction in IC50 ) cisplatin, carboplatin, and etoposide in vitro in five of nine SCLC cell lines. Veliparib with cisplatin or etoposide or with both cisplatin and etoposide showed greater delay in tumor growth than chemotherapy alone in H146 but not H128 xenografts. The potentiating effect of veliparib was associated with in vitro cell line sensitivity to cisplatin (CC = 0.672; P = 0.048) and DNA-PKcs protein modulation. Gene expression profiling identified differential expression of a 5-gene panel (GLS, UBEC2, HACL1, MSI2, and LOC100129585) in cell lines with relatively greater sensitivity to platinum and veliparib combination. Veliparib potentiates standard cytotoxic agents against SCLC in a cell-specific manner. This potentiation correlates with platinum sensitivity, DNA-PKcs expression and a 5-gene expression profile.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Benzimidazoles/pharmacology , Lung Neoplasms/drug therapy , Lung Neoplasms/radiotherapy , Poly(ADP-ribose) Polymerase Inhibitors , Small Cell Lung Carcinoma/drug therapy , Small Cell Lung Carcinoma/radiotherapy , Animals , Benzimidazoles/administration & dosage , Carboplatin/administration & dosage , Carboplatin/pharmacology , Cell Line, Tumor , Chemoradiotherapy , Cisplatin/administration & dosage , Cisplatin/pharmacology , Drug Synergism , Etoposide/administration & dosage , Etoposide/pharmacology , Humans , In Vitro Techniques , Lung Neoplasms/pathology , Mice , Mice, Nude , Random Allocation , Small Cell Lung Carcinoma/pathology , Xenograft Model Antitumor Assays
11.
Cancer ; 119(11): 1951-9, 2013 Jun 01.
Article in English | MEDLINE | ID: mdl-23512358

ABSTRACT

BACKGROUND: Depression is common during and after breast cancer treatment. However, the role of specific therapeutic modalities and related biologic mechanisms remains unclear. Radiation is an essential component of breast-conserving therapy and may contribute to depression in patients with breast cancer through the activation of inflammatory pathways. METHODS: Depressive symptoms and inflammatory mediators, including nuclear factor kappa B (NF-κB), were assessed at baseline (before radiation), during radiation, and 6 weeks after radiation in 64 women who had stage 0 through IIIA breast cancer. RESULTS: No significant increases in depressive symptoms occurred during or after radiation, although a number of patients exhibited moderate-to-severe depression throughout the study. Multivariate analyses of baseline factors predictive of depression revealed that educational status, perceived stress, prior chemotherapy, and peripheral blood NF-κB DNA binding all were independent predictors of persistent depressive symptoms after radiation (all P < .05). Of these factors, only prior chemotherapy was associated with inflammatory mediators, including NF-κB DNA binding, soluble tumor necrosis factor-alpha receptor 2, and interleukin-6, which, in univariate analyses predicted depressive symptoms after radiation (all P < .05). Chemotherapy-treated patients also exhibited an over-representation of gene transcripts regulated by NF-κB. CONCLUSIONS: Radiation was not associated with increased depressive symptoms in the current study, but of disease and treatment-related factors, prior chemotherapy predicted significant depression after radiation. Longitudinal studies are warranted to investigate the relationship among prior chemotherapy, inflammation, and persistent depression after breast cancer treatment.


Subject(s)
Breast Neoplasms/psychology , Breast Neoplasms/therapy , Depression/etiology , Radiation Injuries/psychology , Adult , Aged , Breast Neoplasms/metabolism , Breast Neoplasms/radiotherapy , Chemotherapy, Adjuvant , Depression/metabolism , Female , Humans , Inflammation Mediators/blood , Inflammation Mediators/metabolism , Interleukin-1/blood , Interleukin-1/metabolism , Interleukin-6/blood , Interleukin-6/metabolism , Middle Aged , NF-kappa B/blood , NF-kappa B/metabolism , Tumor Necrosis Factor-alpha/blood , Tumor Necrosis Factor-alpha/metabolism
12.
J Immunol ; 186(7): 4200-12, 2011 Apr 01.
Article in English | MEDLINE | ID: mdl-21383243

ABSTRACT

T cell dysfunction is an important feature of many chronic viral infections. In particular, it was shown that programmed death-1 (PD-1) regulates T cell dysfunction during chronic lymphocytic choriomeningitis virus infection in mice, and PD-1(hi) cells exhibit an intense exhausted gene signature. These findings were extended to human chronic infections such as HIV, hepatitis C virus, and hepatitis B virus. However, it is not known if PD-1(hi) cells of healthy humans have the traits of exhausted cells. In this study, we provide a comprehensive description of phenotype, function, and gene expression profiles of PD-1(hi) versus PD-1(lo) CD8 T cells in the peripheral blood of healthy human adults as follows: 1) the percentage of naive and memory CD8 T cells varied widely in the peripheral blood cells of healthy humans, and PD-1 was expressed by the memory CD8 T cells; 2) PD-1(hi) CD8 T cells in healthy humans did not significantly correlate with the PD-1(hi) exhausted gene signature of HIV-specific human CD8 T cells or chronic lymphocytic choriomeningitis virus-specific CD8 T cells from mice; 3) PD-1 expression did not directly affect the ability of CD8 T cells to secrete cytokines in healthy adults; 4) PD-1 was expressed by the effector memory compared with terminally differentiated effector CD8 T cells; and 5) finally, an interesting inverse relationship between CD45RA and PD-1 expression was observed. In conclusion, our study shows that most PD-1(hi) CD8 T cells in healthy adult humans are effector memory cells rather than exhausted cells.


Subject(s)
Antigens, CD/biosynthesis , Antigens, CD/genetics , Apoptosis Regulatory Proteins/biosynthesis , Apoptosis Regulatory Proteins/genetics , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Gene Expression Profiling/methods , Immunophenotyping , Adult , Animals , Antigens, CD/physiology , Apoptosis Regulatory Proteins/physiology , CD8-Positive T-Lymphocytes/microbiology , Down-Regulation/genetics , Down-Regulation/immunology , Humans , Immunologic Memory/genetics , Immunologic Memory/immunology , Lymphocyte Activation/genetics , Lymphocyte Activation/immunology , Lymphocyte Count/methods , Lymphocytic choriomeningitis virus/immunology , Mice , Oligonucleotide Array Sequence Analysis/methods , Programmed Cell Death 1 Receptor , Resting Phase, Cell Cycle/genetics , Resting Phase, Cell Cycle/immunology , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , T-Lymphocyte Subsets/microbiology , Up-Regulation/genetics , Up-Regulation/immunology
13.
J Immunol ; 176(4): 2455-64, 2006 Feb 15.
Article in English | MEDLINE | ID: mdl-16456005

ABSTRACT

The sole human cathelicidin peptide, LL-37, has been demonstrated to protect animals against endotoxemia/sepsis. Low, physiological concentrations of LL-37 (< or =1 microg/ml) were able to modulate inflammatory responses by inhibiting the release of the proinflammatory cytokine TNF-alpha in LPS-stimulated human monocytic cells. Microarray studies established a temporal transcriptional profile and identified differentially expressed genes in LPS-stimulated monocytes in the presence or absence of LL-37. LL-37 significantly inhibited the expression of specific proinflammatory genes up-regulated by NF-kappaB in the presence of LPS, including NFkappaB1 (p105/p50) and TNF-alpha-induced protein 2 (TNFAIP2). In contrast, LL-37 did not significantly inhibit LPS-induced genes that antagonize inflammation, such as TNF-alpha-induced protein 3 (TNFAIP3) and the NF-kappaB inhibitor, NFkappaBIA, or certain chemokine genes that are classically considered proinflammatory. Nuclear translocation, in LPS-treated cells, of the NF-kappaB subunits p50 and p65 was reduced > or =50% in the presence of LL-37, demonstrating that the peptide altered gene expression in part by acting directly on the TLR-to-NF-kappaB pathway. LL-37 almost completely prevented the release of TNF-alpha and other cytokines by human PBMC following stimulation with LPS and other TLR2/4 and TLR9 agonists, but not with cytokines TNF-alpha or IL-1beta. Biochemical and inhibitor studies were consistent with a model whereby LL-37 modulated the inflammatory response to LPS/endotoxin and other agonists of TLR by a complex mechanism involving multiple points of intervention. We propose that the natural human host defense peptide LL-37 plays roles in the delicate balancing of inflammatory responses in homeostasis as well as in combating sepsis induced by certain TLR agonists.


Subject(s)
Antimicrobial Cationic Peptides/pharmacology , Inflammation/immunology , Toll-Like Receptors/metabolism , Antimicrobial Cationic Peptides/metabolism , Cell Line , Gene Expression Profiling , Humans , Inflammation/genetics , Inflammation/metabolism , Kinetics , Lipopolysaccharides/pharmacology , NF-kappa B/metabolism , Protein Subunits/metabolism , Protein Transport , Toll-Like Receptors/immunology , Transcription, Genetic/genetics , Tumor Necrosis Factor-alpha/metabolism , Cathelicidins
14.
Biol Blood Marrow Transplant ; 8(12): 648-55, 2002.
Article in English | MEDLINE | ID: mdl-12523576

ABSTRACT

The 4-aminoquinolines, chloroquine and hydroxychloroquine, are established, with a 52% response rate, as therapy for human steroid-refractory GVHD after BMT. Chloroquine affects numerous mechanisms that play a role in GVHD, including inhibition of major histocompatibility complex (MHC) class II antigen presentation, cytokine production, and antigen-presenting cell activation by bacterially derived CpG oligodeoxynucleotides (ODNs). Using an MHC-disparate murine model, we evaluated the effect of chloroquine treatment on the development of acute GVHD. We assessed the effect of chloroquine on the immunostimulatory responses induced by CpG ODNs after BMT. We also evaluated the impact of chloroquine on cytokine-producing populations known to affect GVHD, including CD4+ and CD8+ T-cell and CD3(+)/NK1.1(+) natural killer T-cell (NKT cell) populations. Twelve (86%) of 14 mice receiving phosphate-buffered saline solution (PBS) developed lethal GVHD; only 4 (29%) of 14 mice receiving chloroquine 20 mg/kg 3 times per week developed lethal GVHD (P < .01). Chloroquine significantly suppressed CpG ODN-induced splenic proliferation and interleukin 6 (IL-6) production associated with GVHD. Chloroquine suppressed CD8+ T-cell production of IL-2 and IL-4 associated with GVHD in this model and maintained an early expansion (day 7) of splenic NKT cells. These results indicate that the 4-aminoquinolines are effective in therapy for or prevention of acute GVHD secondary to MHC disparities. Chloroquine actions may include inhibition of CpG ODN augmentation of GVHD. Other mechanisms involved may include suppression of CD8+ T-cell production of IL-2 and IL-4 and an increase in NKT cells associated with GVHD inhibition by chloroquine.


Subject(s)
Bone Marrow Transplantation/immunology , Chloroquine/therapeutic use , Graft vs Host Disease/prevention & control , Major Histocompatibility Complex , Oligodeoxyribonucleotides/pharmacology , Spleen/immunology , T-Lymphocytes/immunology , Animals , Cytokines/biosynthesis , Dinucleoside Phosphates , Female , Graft vs Host Disease/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Inbred Strains , Spleen/drug effects , T-Lymphocytes/drug effects
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