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1.
Rheumatology (Oxford) ; 63(2): 542-550, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37252826

RESUMO

OBJECTIVES: To determine whether an expanded antigen-specific ACPA profile predicts changes in disease activity in patients with RA initiating biologics. METHODS: The study included participants from a prospective, non-randomized, observational RA cohort. For this sub-study, treatment groups of interest included biologic-naïve initiating anti-TNF, biologic-exposed initiating non-TNF, and biologic-naïve initiating abatacept. ACPAs to 25 citrullinated peptides were measured using banked enrolment serum. Principal component analysis (PCA) was performed and associations of resulting principal component (PC) scores (in quartiles) and anti-CCP3 antibody (≤15, 16-250 or >250 U/ml) with EULAR (good/moderate/none) treatment response at 6 months were examined using adjusted ordinal regression models. RESULTS: Participants (n = 1092) had a mean age of 57 (13) years and 79% were women. At 6 months, 68.5% achieved a moderate/good EULAR response. There were three PCs that cumulatively explained 70% of variation in ACPA values. In models including the three components and anti-CCP3 antibody category, only PC1 and PC2 were associated with treatment response. The highest quartile for PC1 (odds ratio [OR] 1.76; 95% CI: 1.22, 2.53) and for PC2 (OR 1.74; 95% CI: 1.23, 2.46) were associated with treatment response after multivariable adjustment. There was no evidence of interaction between PCs and treatment group in EULAR responses (P-value for interaction >0.1). CONCLUSION: An expanded ACPA profile appears to be more strongly associated with biologic treatment response in RA than commercially available anti-CCP3 antibody levels. However, further enhancements to PCA will be needed to effectively prioritize between different biologics available for the treatment of RA.


Assuntos
Antirreumáticos , Artrite Reumatoide , Produtos Biológicos , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Antirreumáticos/uso terapêutico , Anticorpos Antiproteína Citrulinada , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Estudos Prospectivos , Produtos Biológicos/uso terapêutico
2.
J Infect Dis ; 227(3): 371-380, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36314635

RESUMO

BACKGROUND: Evaluating the performance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological assays and clearly articulating the utility of selected antigens, isotypes, and thresholds is crucial to understanding the prevalence of infection within selected communities. METHODS: This cross-sectional study, implemented in 2020, screened PCRconfirmed coronavirus disease 2019 patients (n 86), banked prepandemic and negative samples (n 96), healthcare workers and family members (n 552), and university employees (n 327) for antiSARS-CoV-2 receptor-binding domain, trimeric spike protein, and nucleocapsid protein immunoglobulin (Ig)G and IgA antibodies with a laboratory-developed enzyme-linked immunosorbent assay and tested how antigen, isotype and threshold choices affected the seroprevalence outcomes. The following threshold methods were evaluated: (i) mean 3 standard deviations of the negative controls; (ii) 100 specificity for each antigen-isotype combination; and (iii) the maximal Youden index. RESULTS: We found vastly different seroprevalence estimates depending on selected antigens and isotypes and the applied threshold method, ranging from 0.0 to 85.4. Subsequently, we maximized specificity and reported a seroprevalence, based on more than one antigen, ranging from 9.3 to 25.9. CONCLUSIONS: This study revealed the importance of evaluating serosurvey tools for antigen-, isotype-, and threshold-specific sensitivity and specificity, to interpret qualitative serosurvey outcomes reliably and consistently across studies.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , Estudos Soroepidemiológicos , Estudos Transversais , Proteínas do Nucleocapsídeo , Ensaio de Imunoadsorção Enzimática/métodos , Sensibilidade e Especificidade , Imunoglobulina G , Anticorpos Antivirais , Glicoproteína da Espícula de Coronavírus
3.
J Clin Rheumatol ; 29(7): 332-340, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37644656

RESUMO

BACKGROUND: The type of failure may predict response to a second biologic. We evaluated the response to a second tumor necrosis factor inhibitor (TNFi) or non-TNFi in patients failing their initial TNFi, either primarily or secondarily. METHODS: Patients with rheumatoid arthritis who were biologic-naive and had a Clinical Disease Activity Index (CDAI) >10, who started their first TNFi for ≥3 months and then switched to a second biologic, were included in the study. Secondary failure was defined as 2 consecutive low-CDAI visits and then switching to a second biologic while they had moderate/severe CDAI. Primary failure was defined if it did not meet the definition of secondary failure, or if they had at least 1 moderate/severe CDAI after 3 months on treatment. We used multivariable logistic regression comparing primary versus secondary failure for achievement of CDAI ≤10 (primary outcome) and minimal clinically important differences (secondary outcome) at 6 months after switch. RESULTS: Of the 462 patients included, 64.3% and 35.7% stopped the first TNFi because of a primary and secondary failure, respectively. Patients with primary failure had a more severe disease (CDAI mean, 26.39 vs. 21.61; p < 0.001). The likelihood of achieving CDAI ≤10 (odds ratio, 4.367; 95% confidence interval, 2.428-7.856) and minimal clinically important difference (odds ratio, 2.851; 95% confidence interval, 1.619-5.020) was significantly higher for secondary than primary failure regardless of choice of a second agent. CONCLUSION: Patients with rheumatoid arthritis with secondary failure to a first TNFi responded better to a second biologic agent, regardless of the choice of biologic.


Assuntos
Antirreumáticos , Artrite Reumatoide , Produtos Biológicos , Humanos , Antirreumáticos/uso terapêutico , Fator de Necrose Tumoral alfa , Resultado do Tratamento , Artrite Reumatoide/tratamento farmacológico , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Produtos Biológicos/uso terapêutico
4.
J Infect Dis ; 226(12): 2192-2203, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36201640

RESUMO

BACKGROUND: Likelihood of Neisseria gonorrhoeae infection in women exposed to male sex partners with increasing N. gonorrhoeae burdens and enhancement by Chlamydia trachomatis is not defined. METHODS: We identified men with urethritis and their regular female sex partners. Exposure to N. gonorrhoeae burdens in men was compared in N. gonorrhoeae-infected versus -uninfected partners. Association of N. gonorrhoeae infection in women with burdens in male partners was estimated using logistic regression. Association of C. trachomatis coinfection and N. gonorrhoeae burdens in women adjusted for burdens in male partners was estimated by linear regression. RESULTS: In total, 1816 men were enrolled; 202 had ≥2 partners, 91 who confirmed monogamy and were enrolled; 77% were married. Seventy were partners of N. gonorrhoeae-infected men; 58 (83%) were N. gonorrhoeae infected, 26 (45%) C. trachomatis coinfected. Infected women had partners with 9.3-fold higher N. gonorrhoeae burdens than partners of uninfected women (P = .0041). Association of N. gonorrhoeae infection in women with upper quartiles of N. gonorrhoeae burdens in partners increased (odds ratios ≥ 2.97)compared to the first quartile (P = .032). N. gonorrhoeae burdens in C. trachomatis-coinfected women were 2.82-fold higher than in C. trachomatis-uninfected women (P = .036). CONCLUSIONS: N. gonorrhoeae infections increased in women whose partners were infected with higher N. gonorrhoeae burdens. C. trachomatis coinfection was associated with increased N. gonorrhoeae burdens in women.


Assuntos
Infecções por Chlamydia , Coinfecção , Gonorreia , Feminino , Masculino , Humanos , Gonorreia/complicações , Gonorreia/epidemiologia , Infecções por Chlamydia/complicações , Infecções por Chlamydia/epidemiologia , Coinfecção/epidemiologia , Coinfecção/complicações , Chlamydia trachomatis , Neisseria gonorrhoeae
5.
Ann Rheum Dis ; 80(12): 1522-1529, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34215644

RESUMO

OBJECTIVES: Rheumatoid arthritis (RA), along with glucocorticoid use, is associated with cardiovascular disease. Cardiovascular safety of glucocorticoids in RA is controversial and may be related to dose and duration of use. We determined if initiating glucocorticoids in steroid-naive RA patients would increase cardiovascular event (CVE) risk in a dose and duration-dependent manner over short-term intervals. METHODS: Patients enrolled in CorEvitas (formerly Corrona) RA registry. Cox proportional-hazards models estimated adjusted HRs (aHR) for incident CVE in patients who initiated glucocorticoid treatment, adjusting for RA duration, traditional cardiovascular risk factors and time-varying covariates: Clinical Disease activity Index, disease-modifying antirheumatic drugs use and prednisone-equivalent use. Glucocorticoid use assessed current daily dose, cumulative dose and duration of use over rolling intervals of preceding 6 months and 1 year. RESULTS: 19 902 patients met criteria. 1106 CVE occurred (1.66/100 person-years). Increased aHR occurred at current doses of ≥5-9 mg 1.56 (1.18-2.06) and ≥10 mg 1.91 (1.31-2.79), without increased risk at 0-4 mg 1.04 (0.55-1.59). Cumulative dose over preceding 6 months showed increased aHR at 751-1100 mg 1.43 (1.04-1.98) and >1100 mg 2.05 (1.42-2.94), without increased risk at lower doses; duration of use over preceding 6 months exhibited increased aHR for >81 days of use 1.54 (1.08-2.32), without increased risk at shorter durations. One-year analyses were consistent. CONCLUSIONS: Over preceding 6-month and 1-year intervals, initiating glucocorticoids in steroid-naïve RA patients is associated with increased risk of CVE at daily doses ≥5 mg and increased cumulative dose and duration of use. No association with risk for CVE was found with daily prednisone of ≤4 mg or shorter cumulative doses and durations.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Doenças Cardiovasculares/epidemiologia , Duração da Terapia , Glucocorticoides/uso terapêutico , Prednisona/uso terapêutico , Síndrome Coronariana Aguda/epidemiologia , Adulto , Idoso , Angina Instável/epidemiologia , Antirreumáticos/uso terapêutico , Arritmias Cardíacas/epidemiologia , Artrite Reumatoide/fisiopatologia , Doenças Cardiovasculares/mortalidade , Relação Dose-Resposta a Droga , Feminino , Fatores de Risco de Doenças Cardíacas , Insuficiência Cardíaca/epidemiologia , Hospitalização/estatística & dados numéricos , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Revascularização Miocárdica/estatística & dados numéricos , Doença Arterial Periférica/epidemiologia , Modelos de Riscos Proporcionais , Embolia Pulmonar/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Tromboembolia/epidemiologia , Trombose Venosa/epidemiologia
6.
Immunity ; 37(1): 96-107, 2012 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-22840842

RESUMO

Yersinia pestis, the causative agent of plague, is able to suppress production of inflammatory cytokines IL-18 and IL-1ß, which are generated through caspase-1-activating nucleotide-binding domain and leucine-rich repeat (NLR)-containing inflammasomes. Here, we sought to elucidate the role of NLRs and IL-18 during plague. Lack of IL-18 signaling led to increased susceptibility to Y. pestis, producing tetra-acylated lipid A, and an attenuated strain producing a Y. pseudotuberculosis-like hexa-acylated lipid A. We found that the NLRP12 inflammasome was an important regulator controlling IL-18 and IL-1ß production after Y. pestis infection, and NLRP12-deficient mice were more susceptible to bacterial challenge. NLRP12 also directed interferon-γ production via induction of IL-18, but had minimal effect on signaling to the transcription factor NF-κB. These studies reveal a role for NLRP12 in host resistance against pathogens. Minimizing NLRP12 inflammasome activation may have been a central factor in evolution of the high virulence of Y. pestis.


Assuntos
Inflamassomos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peste/imunologia , Peste/metabolismo , Yersinia pestis/imunologia , Animais , Inflamassomos/imunologia , Interferon gama/biossíntese , Interleucina-18/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peste/mortalidade , Transdução de Sinais
7.
Clin Infect Dis ; 70(5): 805-810, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-30972419

RESUMO

BACKGROUND: Mycoplasma genitalium (MG) causes symptomatic urethritis in men, and can infect alone or together with other sexually transmitted infection (STI) agents. METHODS: The prevalence of MG and other STIs was determined in 1816 men with symptomatic urethritis. Resistance of MG to macrolides and fluoroquinolones was determined by sequencing; the impact of recent antimicrobial usage on the distribution of MG single or mixed infections was determined. RESULTS: Overall, prevalence of MG infection was 19.7% (358/1816). Fifty-four percent (166/307) of MG infections occurred alone in the absence of other STI agents. Men with single MG infection self-administered or were prescribed antibiotics more often in the 30 days prior to enrollment than subjects with urethritis caused by MG coinfection (P < .0001). Higher rates (96.7%) of infection with macrolide resistance in MG were identified in men who had taken macrolides prior to enrollment (P < .03). Overall, 88.9% (303/341) of 23S ribosomal RNA (rRNA) genes contained mutations responsible for macrolide resistance; 89.5% (308/344) of parC and 12.4% (42/339) of gyrA genes had mutations responsible for fluoroquinolone resistance. Approximately 88% (270/308) of MG had combined mutations in 23S rRNA and parC genes; 10.4% (32/308) had mutations in all 3 genes. CONCLUSIONS: MG was the single pathogen identified in 11% of men with symptomatic urethritis. Overall, nearly 90% of MG infections were resistant to macrolides and fluoroquinolones. Men who took macrolides in the 30 days prior to enrollment had higher rates (97%) of macrolide-resistant MG. Resistance was associated with numerous mutations in 23SrRNA, parC, and gyrA genes.


Assuntos
Infecções por Mycoplasma , Mycoplasma genitalium , Uretrite , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , DNA Bacteriano , Farmacorresistência Bacteriana , Humanos , Macrolídeos/farmacologia , Macrolídeos/uso terapêutico , Masculino , Infecções por Mycoplasma/tratamento farmacológico , Infecções por Mycoplasma/epidemiologia , Mycoplasma genitalium/genética , RNA Ribossômico 23S/genética , Uretrite/tratamento farmacológico , Uretrite/epidemiologia
8.
J Immunol ; 201(9): 2700-2709, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30266769

RESUMO

Novel therapeutics against multidrug-resistant Neisseria gonorrhoeae are urgently needed. Gonococcal lipooligosaccharide often expresses lacto-N-neotetraose (LNnT), which becomes sialylated in vivo, enhancing factor H (FH) binding and contributing to the organism's ability to resist killing by complement. We previously showed that FH domains 18-20 (with a D-to-G mutation at position 1119 in domain 19) fused to Fc (FHD1119G/Fc) displayed complement-dependent bactericidal activity in vitro and attenuated gonococcal vaginal colonization of mice. Gonococcal lipooligosaccharide phase variation can result in loss of LNnT expression. Loss of sialylated LNnT, although associated with a considerable fitness cost, could decrease efficacy of FHD1119G/Fc. Similar to N. meningitidis, gonococci also bind FH domains 6 and 7 through Neisserial surface protein A (NspA). In this study, we show that a fusion protein comprising FH domains 6 and 7 fused to human IgG1 Fc (FH6,7/Fc) bound to 15 wild-type antimicrobial resistant isolates of N. gonorrhoeae and to each of six lgtA gonococcal deletion mutants. FH6,7/Fc mediated complement-dependent killing of 8 of the 15 wild-type gonococcal isolates and effectively reduced the duration and burden of vaginal colonization of three gonococcal strains tested in wild-type mice, including two strains that resisted complement-dependent killing but on which FH6,7/Fc enhanced C3 deposition. FH/Fc lost efficacy when Fc was mutated to abrogate C1q binding and in C1q-/- mice, highlighting the requirement of the classical pathway for its activity. Targeting gonococci with FH6,7/Fc provides an additional immunotherapeutic approach against multidrug-resistant gonorrhea.


Assuntos
Gonorreia , Fragmentos Fc das Imunoglobulinas , Imunoterapia/métodos , Proteínas Recombinantes de Fusão/farmacologia , Animais , Fator H do Complemento , Humanos , Imunoglobulina G , Camundongos , Neisseria gonorrhoeae/imunologia
9.
J Immunol ; 200(4): 1243-1248, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29330325

RESUMO

Malarial infection in naive individuals induces a robust innate immune response. In the recently described model of innate immune memory, an initial stimulus primes the innate immune system to either hyperrespond (termed training) or hyporespond (tolerance) to subsequent immune challenge. Previous work in both mice and humans demonstrated that infection with malaria can both serve as a priming stimulus and promote tolerance to subsequent infection. In this study, we demonstrate that initial stimulation with Plasmodium falciparum-infected RBCs or the malaria crystal hemozoin induced human adherent PBMCs to hyperrespond to subsequent ligation of TLR2. This hyperresponsiveness correlated with increased H3K4me3 at important immunometabolic promoters, and these epigenetic modifications were also seen in Kenyan children naturally infected with malaria. However, the use of epigenetic and metabolic inhibitors indicated that the induction of trained immunity by malaria and its ligands may occur via a previously unrecognized mechanism(s).


Assuntos
Imunidade Inata/imunologia , Malária Falciparum/imunologia , Criança , Pré-Escolar , Epigênese Genética/imunologia , Feminino , Regulação da Expressão Gênica/imunologia , Histonas/biossíntese , Humanos , Lactente , Malária Falciparum/metabolismo , Masculino
10.
Infect Immun ; 86(8)2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29844237

RESUMO

Sialylation of lacto-N-neotetraose (LNnT) extending from heptose I (HepI) of gonococcal lipooligosaccharide (LOS) contributes to pathogenesis. Previously, gonococcal LOS sialyltransterase (Lst) was shown to sialylate LOS in Triton X-100 extracts of strain 15253, which expresses lactose from both HepI and HepII, the minimal structure required for monoclonal antibody (MAb) 2C7 binding. Ongoing work has shown that growth of 15253 in cytidine monophospho-N-acetylneuraminic acid (CMP-Neu5Ac)-containing medium enables binding to CD33/Siglec-3, a cell surface receptor that binds sialic acid, suggesting that lactose termini on LOSs of intact gonococci can be sialylated. Neu5Ac was detected on LOSs of strains 15253 and an MS11 mutant with lactose only from HepI and HepII by mass spectrometry; deleting HepII lactose rendered Neu5Ac undetectable. Resistance of HepII lactose Neu5Ac to desialylation by α2-3-specific neuraminidase suggested an α2-6 linkage. Although not associated with increased factor H binding, HepII lactose sialylation inhibited complement C3 deposition on gonococci. Strain 15253 mutants that lacked Lst or HepII lactose were significantly attenuated in mice, confirming the importance of HepII Neu5Ac in virulence. All 75 minimally passaged clinical isolates from Nanjing, China, expressed HepII lactose, evidenced by reactivity with MAb 2C7; MAb 2C7 was bactericidal against the first 62 (of 75) isolates that had been collected sequentially and were sialylated before testing. MAb 2C7 effectively attenuated 15253 vaginal colonization in mice. In conclusion, this novel sialylation site could explain the ubiquity of gonococcal HepII lactose in vivo Our findings reinforce the candidacy of the 2C7 epitope as a vaccine antigen and MAb 2C7 as an immunotherapeutic antibody.


Assuntos
Gonorreia/microbiologia , Heptoses/metabolismo , Lactose/metabolismo , Lipopolissacarídeos/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Neisseria gonorrhoeae/metabolismo , Neisseria gonorrhoeae/patogenicidade , Adulto , Animais , Anticorpos Antibacterianos/imunologia , Anticorpos Antibacterianos/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , China , Modelos Animais de Doenças , Feminino , Voluntários Saudáveis , Humanos , Lipopolissacarídeos/química , Masculino , Espectrometria de Massas , Camundongos , Viabilidade Microbiana/efeitos dos fármacos , Ácido N-Acetilneuramínico/análise , Neisseria gonorrhoeae/química , Neisseria gonorrhoeae/isolamento & purificação
11.
J Immunol ; 196(4): 1732-40, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26773149

RESUMO

Neisseria gonorrhoeae, the causative agent of the sexually transmitted infection gonorrhea, has developed resistance to almost every conventional antibiotic. There is an urgent need to develop novel therapies against gonorrhea. Many pathogens, including N. gonorrhoeae, bind the complement inhibitor factor H (FH) to evade complement-dependent killing. Sialylation of gonococcal lipooligosaccharide, as occurs in vivo, augments binding of human FH through its domains 18-20 (FH18-20). We explored the use of fusing FH18-20 with IgG Fc (FH18-20/Fc) to create a novel anti-infective immunotherapeutic. FH18-20 also binds to select host glycosaminoglycans to limit unwanted complement activation on host cells. To identify mutation(s) in FH18-20 that eliminated complement activation on host cells, yet maintained binding to N. gonorrhoeae, we created four mutations in domains 19 or 20 described in atypical hemolytic uremic syndrome that prevented binding of mutated fH to human erythrocytes. One of the mutant proteins (D to G at position 1119 in domain 19; FHD1119G/Fc) facilitated complement-dependent killing of gonococci similar to unmodified FH18-20/Fc but, unlike FH18-20/Fc, did not lyse human erythrocytes. FHD1119G/Fc bound to all (100%) of 15 sialylated clinical N. gonorrhoeae isolates tested (including three contemporary ceftriaxone-resistant strains), mediated complement-dependent killing of 10 of 15 (67%) strains, and enhanced C3 deposition (≥10-fold above baseline levels) on each of the five isolates not directly killed by complement. FHD1119G/Fc facilitated opsonophagocytic killing of a serum-resistant strain by human polymorphonuclear neutrophils. FHD1119G/Fc administered intravaginally significantly reduced the duration and burden of gonococcal infection in the mouse vaginal colonization model. FHD1119G/Fc represents a novel immunotherapeutic against multidrug-resistant N. gonorrhoeae.


Assuntos
Fator H do Complemento/imunologia , Gonorreia/imunologia , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoterapia/métodos , Proteínas Recombinantes de Fusão/imunologia , Animais , Fator H do Complemento/farmacologia , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Humanos , Fragmentos Fc das Imunoglobulinas/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Neisseria gonorrhoeae/imunologia , Proteínas Recombinantes de Fusão/farmacologia
12.
Biochemistry ; 56(22): 2824-2835, 2017 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-28514140

RESUMO

Oxalate:ferredoxin oxidoreductase (OOR) is an unusual member of the thiamine pyrophosphate (TPP)-dependent 2-oxoacid:ferredoxin oxidoreductase (OFOR) family in that it catalyzes the coenzyme A (CoA)-independent conversion of oxalate into 2 equivalents of carbon dioxide. This reaction is surprising because binding of CoA to the acyl-TPP intermediate of other OFORs results in formation of a CoA ester, and in the case of pyruvate:ferredoxin oxidoreductase (PFOR), CoA binding generates the central metabolic intermediate acetyl-CoA and promotes a 105-fold acceleration of the rate of electron transfer. Here we describe kinetic, spectroscopic, and computational results to show that CoA has no effect on catalysis by OOR and describe the chemical rationale for why this cofactor is unnecessary in this enzymatic transformation. Our results demonstrate that, like PFOR, OOR binds pyruvate and catalyzes decarboxylation to form the same hydroxyethylidine-TPP (HE-TPP) intermediate and one-electron transfer to generate the HE-TPP radical. However, in OOR, this intermediate remains stranded at the active site as a covalent inhibitor. These and other results indicate that, like other OFOR family members, OOR generates an oxalate-derived adduct with TPP (oxalyl-TPP) that undergoes decarboxylation and one-electron transfer to form a radical intermediate remaining bound to TPP (dihydroxymethylidene-TPP). However, unlike in PFOR, where CoA binding drives formation of the product, in OOR, proton transfer and a conformational change in the "switch loop" alter the redox potential of the radical intermediate sufficiently to promote the transfer of an electron into the iron-sulfur cluster network, leading directly to a second decarboxylation and completing the catalytic cycle.


Assuntos
Oxalatos/metabolismo , Oxirredutases/metabolismo , Ácido Pirúvico/metabolismo , Catálise , Espectroscopia de Ressonância de Spin Eletrônica , Espectrofotometria Ultravioleta
13.
PLoS Pathog ; 11(12): e1005290, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26630657

RESUMO

Neisseria gonorrhoeae deploys a novel immune evasion strategy wherein the lacto-N-neotetraose (LNnT) structure of lipooligosaccharide (LOS) is capped by the bacterial sialyltransferase, using host cytidine-5'-monophosphate (CMP)-activated forms of the nine-carbon nonulosonate (NulO) sugar N-acetyl-neuraminic acid (Neu5Ac), a sialic acid (Sia) abundant in humans. This allows evasion of complement-mediated killing by recruiting factor H (FH), an inhibitor of the alternative complement pathway, and by limiting classical pathway activation ("serum-resistance"). We utilized CMP salts of six additional natural or synthetic NulOs, Neu5Gc, Neu5Gc8Me, Neu5Ac9Ac, Neu5Ac9Az, legionaminic acid (Leg5Ac7Ac) and pseudaminic acid (Pse5Ac7Ac), to define structural requirements of Sia-mediated serum-resistance. While all NulOs except Pse5Ac7Ac were incorporated into the LNnT-LOS, only Neu5Gc incorporation yielded high-level serum-resistance and FH binding that was comparable to Neu5Ac, whereas Neu5Ac9Az and Leg5Ac7Ac incorporation left bacteria fully serum-sensitive and did not enhance FH binding. Neu5Ac9Ac and Neu5Gc8Me rendered bacteria resistant only to low serum concentrations. While serum-resistance mediated by Neu5Ac was associated with classical pathway inhibition (decreased IgG binding and C4 deposition), Leg5Ac7Ac and Neu5Ac9Az incorporation did not inhibit the classical pathway. Remarkably, CMP-Neu5Ac9Az and CMP-Leg5Ac7Ac each prevented serum-resistance despite a 100-fold molar excess of CMP-Neu5Ac in growth media. The concomitant presence of Leg5Ac7Ac and Neu5Ac on LOS resulted in uninhibited classical pathway activation. Surprisingly, despite near-maximal FH binding in this instance, the alternative pathway was not regulated and factor Bb remained associated with bacteria. Intravaginal administration of CMP-Leg5Ac7Ac to BALB/c mice infected with gonorrhea (including a multidrug-resistant isolate) reduced clearance times and infection burden. Bacteria recovered from CMP-Leg5Ac7Ac-treated mice were sensitive to human complement ex vivo, simulating in vitro findings. These data reveal critical roles for the Sia exocyclic side-chain in gonococcal serum-resistance. Such CMP-NulO analogs may provide a novel therapeutic strategy against the global threat of multidrug-resistant gonorrhea.


Assuntos
Monofosfato de Citidina/análogos & derivados , Resistência Microbiana a Medicamentos/imunologia , Resistência a Múltiplos Medicamentos/imunologia , Gonorreia/imunologia , Ácidos Siálicos/farmacologia , Animais , Western Blotting , Proteínas do Sistema Complemento/imunologia , Monofosfato de Citidina/farmacologia , Ácido N-Acetilneuramínico do Monofosfato de Citidina/análogos & derivados , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Gonorreia/metabolismo , Humanos , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/metabolismo , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos BALB C , Neisseria gonorrhoeae/imunologia , Neisseria gonorrhoeae/metabolismo
14.
Rheumatology (Oxford) ; 56(7): 1095-1101, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28340006

RESUMO

Objectives: To compare clinical outcomes and treatment patterns among patients with moderate vs severe RA following biologic DMARD initiation. Methods: Biologics-naive patients with moderate to severe RA [Clinical Disease Activity Index (CDAI) >10] who initiated a biologic DMARD were selected from the Corrona registry (2001-13). CDAI, functional status [modified HAQ (mHAQ)] and patterns of drug use were compared at 1 and 2 years post-initiation between patients with moderate (CDAI >10⩽22) vs severe (CDAI >22) baseline disease activity. Results: A total of 1596 patients (817 severe, 779 moderate) had ⩾1 year of follow-up and 1269 (635 severe, 634 moderate) had ⩾2 years of follow-up. Patients with severe vs moderate baseline disease activity experienced greater improvements in disease activity [mean change in CDAI -18.9 vs -6.0 at year 1; -21.0 vs -7.1 at year 2 ( P < 0.0001)] and physical function [mean change in mHAQ -0.2 vs -0.1 ( P < 0.0001) at year 1; -0.2 vs -0.1 ( P = 0.0013) at year 2]. Greater proportions of patients with moderate vs severe disease activity achieved remission (CDAI ⩽2.8) [22.7 vs 15.8% ( P = 0.0003) at year 1; 25.9 vs 20.9% ( P = 0.0396) at year 2] or low disease activity (CDAI <10) [60.1 vs 41.2% at year 1; 66.7 vs 49.4% at year 2 ( P < 0.0001)]. Most patients remained on the original biologic drug (>70% at year 1; >62% at year 2). Conclusion: With biologic therapy, RA patients with higher baseline disease activity achieved greater improvements in measures of disease activity than those with lower levels of disease, but less often achieved the common targets of remission or low disease activity.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Produtos Biológicos/uso terapêutico , Qualidade de Vida , Sistema de Registros , Adulto , Fatores Etários , Idoso , Artrite Reumatoide/psicologia , Progressão da Doença , Relação Dose-Resposta a Droga , Esquema de Medicação , Medicina Baseada em Evidências , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
15.
Ann Rheum Dis ; 75(10): 1789-96, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26621482

RESUMO

BACKGROUND: The overall incidence of cancer in patients with rheumatoid arthritis (RA) is modestly elevated. The extent to which cancer rates in RA vary across clinical cohorts and patient subsets, as defined by disease activity or treatment is less known but critical for understanding the safety of existing and new antirheumatic therapies. We investigated comparability of, and means to harmonise, malignancy rates in five RA registries from four continents. METHODS: Participating RA registries were Consortium of Rheumatology Researchers of North America (CORRONA) (USA), Swedish Rheumatology Quality of Care Register (SRR) (Sweden), Norfolk Arthritis Register (NOAR) (UK), CORRONA International (several countries) and Institute of Rheumatology, Rheumatoid Arthritis (IORRA) (Japan). Within each registry, we analysed a main cohort of all patients with RA from January 2000 to last available data, and sensitivity analyses of sub-cohorts defined by disease activity, treatment change, prior comorbidities and restricted by calendar time or follow-up, respectively. Malignancy rates with 95% CIs were estimated, and standardised for age and sex, based on the distributions from a typical RA clinical trial programme population (fostamatinib). RESULTS: There was a high consistency in rates for overall malignancy excluding non-melanoma skin cancer (NMSC), for malignant lymphomas, but not for all skin cancers, across registries, in particular following age/sex standardisation. Standardised rates of overall malignancy excluding NMSC varied from 0.56 to 0.87 per 100 person-years. Within each registry, rates were generally consistent across sensitivity analyses, which differed little from the main analysis. CONCLUSION: In real-world RA populations, rates of both overall malignancy and of lymphomas are consistent.


Assuntos
Artrite Reumatoide/complicações , Linfoma/epidemiologia , Neoplasias/epidemiologia , Sistema de Registros/estatística & dados numéricos , Idoso , Feminino , Humanos , Incidência , Japão/epidemiologia , Linfoma/etiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/etiologia , América do Norte/epidemiologia , Suécia/epidemiologia , Reino Unido/epidemiologia
16.
Ann Rheum Dis ; 75(10): 1797-805, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26857699

RESUMO

BACKGROUND: We implemented a novel method for providing contextual adverse event rates for a randomised controlled trial (RCT) programme through coordinated analyses of five RA registries, focusing here on cardiovascular disease (CVD) and mortality. METHODS: Each participating registry (Consortium of Rheumatology Researchers of North America (CORRONA) (USA), Swedish Rheumatology Quality of Care Register (SRR) (Sweden), Norfolk Arthritis Register (NOAR) (UK), CORRONA International (East Europe, Latin America, India) and Institute of Rheumatology, Rheumatoid Arthritis (IORRA) (Japan)) defined a main cohort from January 2000 onwards. To address comparability and potential bias, we harmonised event definitions and defined several subcohorts for sensitivity analyses based on disease activity, treatment, calendar time, duration of follow-up and RCT exclusions. Rates were standardised for age, sex and, in one sensitivity analysis, also HAQ. RESULTS: The combined registry cohorts included 57 251 patients with RA (234 089 person-years)-24.5% men, mean (SD) baseline age 58.2 (13.8) and RA duration 8.2 (11.7) years. Standardised registry mortality rates (per 100 person-years) varied from 0.42 (CORRONA) to 0.80 (NOAR), with 0.60 for RCT patients. Myocardial infarction and major adverse cardiovascular events (MACE) rates ranged from 0.09 and 0.31 (IORRA) to 0.39 and 0.77 (SRR), with RCT rates intermediate (0.18 and 0.42), respectively. Additional subcohort analyses showed small and mostly consistent changes across registries, retaining reasonable consistency in rates across the Western registries. Additional standardisation for HAQ returned higher mortality and MACE registry rates. CONCLUSIONS: This coordinated approach to contextualising RA RCT safety data demonstrated reasonable differences and consistency in rates for mortality and CVD across registries, and comparable RCT rates, and may serve as a model method to supplement clinical trial analyses for drug development programmes.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Doenças Cardiovasculares/mortalidade , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Sistema de Registros/estatística & dados numéricos , Idoso , Artrite Reumatoide/complicações , Viés , Doenças Cardiovasculares/etiologia , Europa (Continente)/epidemiologia , Feminino , Humanos , Índia/epidemiologia , Japão/epidemiologia , América Latina/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , América do Norte/epidemiologia , Suécia/epidemiologia , Resultado do Tratamento
17.
PLoS Pathog ; 10(1): e1003885, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24453977

RESUMO

Cyclic paroxysm and high fever are hallmarks of malaria and are associated with high levels of pyrogenic cytokines, including IL-1ß. In this report, we describe a signature for the expression of inflammasome-related genes and caspase-1 activation in malaria. Indeed, when we infected mice, Plasmodium infection was sufficient to promote MyD88-mediated caspase-1 activation, dependent on IFN-γ-priming and the expression of inflammasome components ASC, P2X7R, NLRP3 and/or NLRP12. Pro-IL-1ß expression required a second stimulation with LPS and was also dependent on IFN-γ-priming and functional TNFR1. As a consequence of Plasmodium-induced caspase-1 activation, mice produced extremely high levels of IL-1ß upon a second microbial stimulus, and became hypersensitive to septic shock. Therapeutic intervention with IL-1 receptor antagonist prevented bacterial-induced lethality in rodents. Similar to mice, we observed a significantly increased frequency of circulating CD14(+)CD16(-)Caspase-1(+) and CD14(dim)CD16(+)Caspase-1(+) monocytes in peripheral blood mononuclear cells from febrile malaria patients. These cells readily produced large amounts of IL-1ß after stimulation with LPS. Furthermore, we observed the presence of inflammasome complexes in monocytes from malaria patients containing either NLRP3 or NLRP12 pyroptosomes. We conclude that NLRP12/NLRP3-dependent activation of caspase-1 is likely to be a key event in mediating systemic production of IL-1ß and hypersensitivity to secondary bacterial infection during malaria.


Assuntos
Infecções Bacterianas/metabolismo , Proteínas de Transporte/metabolismo , Caspase 1/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Malária Vivax/microbiologia , Plasmodium chabaudi/metabolismo , Plasmodium vivax/metabolismo , Animais , Infecções Bacterianas/genética , Infecções Bacterianas/imunologia , Proteínas de Transporte/genética , Proteínas de Transporte/imunologia , Caspase 1/genética , Caspase 1/imunologia , Feminino , Humanos , Inflamassomos/genética , Inflamassomos/imunologia , Inflamassomos/metabolismo , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/patologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Malária Vivax/imunologia , Malária Vivax/metabolismo , Malária Vivax/patologia , Masculino , Camundongos , Camundongos Knockout , Monócitos/imunologia , Monócitos/metabolismo , Monócitos/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Plasmodium chabaudi/imunologia , Plasmodium vivax/imunologia , Choque Séptico/genética , Choque Séptico/imunologia , Choque Séptico/metabolismo , Choque Séptico/patologia
18.
J Infect Dis ; 212(2): 311-5, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25596304

RESUMO

Antibodies against reduction modifiable protein (anti-Rmp Abs) can block complement-dependent killing of Neisseria gonorrhoeae by otherwise bactericidal Abs. An anti-lipooligosaccharide bactericidal monoclonal Ab (mAb) 2C7, a gonococcal vaccine candidate Ab, attenuates vaginal colonization by gonococci in BALB/c mice. Here we show that anti-Rmp Abs block the efficacy of mAb 2C7 in mice in a dose-dependent manner. Anti-Rmp Abs also counteract 2C7-mediated enhancement of C3 deposition on gonococci in vivo. The mouse model will prove useful to study how blocking Abs influence the efficacy of gonococcal vaccines. Preexisting anti-Rmp Abs will be an important consideration in evaluating the efficacy of gonococcal vaccine candidates.


Assuntos
Anticorpos Antibacterianos/administração & dosagem , Proteínas da Membrana Bacteriana Externa/imunologia , Gonorreia/imunologia , Neisseria gonorrhoeae/imunologia , Animais , Antígenos de Bactérias/imunologia , Carga Bacteriana/imunologia , Feminino , Gonorreia/microbiologia , Gonorreia/terapia , Humanos , Imunização Passiva , Camundongos Endogâmicos BALB C
19.
Ann Rheum Dis ; 74(2): 430-6, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24297378

RESUMO

OBJECTIVE: We compared the effectiveness of abatacept (ABA) versus a subsequent anti-tumour necrosis factor inhibitor (anti-TNF) in rheumatoid arthritis (RA) patients with prior anti-TNF use. METHODS: We identified RA patients from a large observational US cohort (2/1/2000-8/7/2011) who had discontinued at least one anti-TNF and initiated either ABA or a subsequent anti-TNF. Using propensity score (PS) matching (n:1 match), effectiveness was measured at 6 and 12 months after initiation based on mean change in Clinical Disease Activity Index (CDAI), modified American College of Rheumatology (mACR) 20, 50 and 70 responses, modified Health Assessment Questionnaire (mHAQ) and CDAI remission in adjusted regression models. RESULTS: The PS-matched groups included 431 ABA and 746 anti-TNF users at 6 months and 311 ABA and 493 anti-TNF users at 12 months. In adjusted analyses comparing response following treatment with ABA and anti-TNF, the difference in weighted mean change in CDAI (range 6-8) at 6 months (0.46, 95% CI -0.82 to 1.73) and 12 months was similar (-1.64, 95% CI -3.47 to 0.19). The mACR20 responses were similar at 6 (28-32%, p=0.73) and 12 months (35-37%, p=0.48) as were the mACR50 and mACR70 (12 months: 20-22%, p=0.25 and 10-12%, p=0.49, respectively). Meaningful change in mHAQ was similar at 6 and 12 months (30-33%, p=0.41 and 29-30%, p=0.39, respectively) as was CDAI remission rates (9-10%, p=0.42 and 12-13%, p=0.91, respectively). CONCLUSIONS: RA patients with prior anti-TNF exposures had similar outcomes if they switched to a new anti-TNF as compared with initiation of ABA.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Imunoconjugados/uso terapêutico , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Abatacepte , Adulto , Idoso , Produtos Biológicos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Ann Rheum Dis ; 74(6): 1150-5, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25471471

RESUMO

BACKGROUND: There is increasing interest in discontinuing biological therapies for patients with rheumatoid arthritis (RA) achieving good clinical responses, provided patients maintain clinical benefit. METHODS: We assessed patients with RA from the Corrona registry who discontinued treatment with their first tumour necrosis factor inhibitor (TNFi) while in low-disease activity (LDA) or lower levels of disease activity. Patients were followed until they lost clinical benefit, defined as increased disease activity or change in RA medications. Duration of maintenance of clinical benefit was estimated using the Kaplan-Meier method. Cox proportional hazard models were assessed to identify factors related to maintenance of benefit. RESULTS: We identified 717 eligible patients with RA from 35,656 in the Corrona registry. At discontinuation, patients had a median RA duration of 8 years, mean clinical disease activity score of 4.3±0.11; 41.8% were using TNFi as monotherapy. 73.4% of patients maintained benefit for >12 months after discontinuing therapy and 42.2% did so through 24 months. Factors predictive of maintaining clinical benefit in multivariate analysis included lower disease activity, less pain and better functional status at the time of TNFi discontinuation. Among 301 patients initiating their first TNFi within the registry, faster responders (ie, those who achieved LDA in 4 months or less) did better than slower responders (HR 1.54 (95% CI 1.17 to 2.04)). RA disease duration did not affect maintenance of clinical benefit. CONCLUSIONS: Discontinuation of a first course of TNFi may be associated with persistent clinical benefit. Half of patients maintained response through 20 months. Several patient characteristics may help predict persistent benefit.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Quimioterapia de Manutenção/métodos , Metotrexato/uso terapêutico , Sistema de Registros , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Idoso , Feminino , Humanos , Estimativa de Kaplan-Meier , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Indução de Remissão , Resultado do Tratamento
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