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1.
J Infect Dis ; 220(8): 1367-1376, 2019 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-31233130

RESUMO

BACKGROUND: Pneumococci and nontypeable Haemophilus influenzae (NTHi) often cocolonize children. The impact of species interactions on disease risk across the upper respiratory mucosa is not known. METHODS: We analyzed data from 4104 acute conjunctivitis (AC) cases, 11 767 otitis media (OM) cases, and 1587 nasopharyngeal specimens collected from Israeli children before pneumococcal conjugate vaccine introduction. We compared pneumococcal serotype distributions with NTHi present and absent, and compared single-species and mixed-species rates of serotype-specific progression from colonization to AC and OM. RESULTS: Pneumococcal serotypes causing single-species OM (NTHi absent) were less diverse than colonizing serotypes and also less diverse than those causing mixed-species OM; colonizing and OM-causing pneumococcal serotype distributions were more similar to each other with NTHi present than with NTHi absent. In contrast, serotype diversity did not differ appreciably between colonizing and AC-causing pneumococci, regardless of NTHi co-occurrence. The similarity of colonizing and AC-causing pneumococcal serotype distributions was consistent in the presence and absence of NTHi. Differences in rates that pneumococcal serotypes progressed from colonization to disease were reduced in both AC and OM when NTHi was present. CONCLUSIONS: Interactions with NTHi may alter progression of pneumococcal serotypes to diseases of the upper respiratory mucosa in a site-specific manner.


Assuntos
Conjuntivite Bacteriana/imunologia , Haemophilus influenzae/imunologia , Interações Microbianas/imunologia , Otite Média/imunologia , Infecções Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Portador Sadio/epidemiologia , Portador Sadio/imunologia , Portador Sadio/microbiologia , Criança , Conjuntivite Bacteriana/epidemiologia , Conjuntivite Bacteriana/microbiologia , Conjuntivite Bacteriana/prevenção & controle , Progressão da Doença , Monitoramento Epidemiológico , Haemophilus influenzae/isolamento & purificação , Humanos , Israel/epidemiologia , Nasofaringe/imunologia , Otite Média/epidemiologia , Otite Média/microbiologia , Otite Média/prevenção & controle , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/microbiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/administração & dosagem , Prevalência , Estudos Prospectivos , Mucosa Respiratória/imunologia , Mucosa Respiratória/microbiologia , Streptococcus pneumoniae/isolamento & purificação
2.
Invest Ophthalmol Vis Sci ; 59(6): 2512-2519, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29847658

RESUMO

Purpose: Bacterial conjunctivitis is a major problem in ocular health. Little is known about protective immune effectors in the conjunctiva. We evaluated whether opsonic antibody to the conserved surface/capsular polysaccharide poly-N-acetyl glucosamine (PNAG) expressed by Streptococcus pneumoniae and Staphylococcus aureus was protective against bacterial conjunctivitis, as well as an antibody to the Pseudomonas aeruginosa surface polysaccharide alginate. Methods: Bacteria were injected directly into the conjunctivae of either A/J mice or into conjunctivae of wild type C57Bl/6 mice for comparisons to responses of recombination activating gene 1-knock out (RAG 1 KO) or germ-free mice in the C57Bl/6 genetic background. Human IgG1 monoclonal antibodies (MAb) to either PNAG or alginate were administered as follows: direct injection of 10 µg into the conjunctivae or topical application onto the cornea 4, 24, and 32 hours post infection; or intraperitoneal injection of 200 µg 18 hours prior to and then 4, 24, and 32-hours postinfection. After 48 hours, eyes were scored for pathology, mice were euthanized, and CFU/conjunctiva was determined. Results: All methods of antibody administration reduced S. pneumoniae, S. aureus, or P. aeruginosa pathology and bacterial levels in the conjunctivae. Histopathologic analysis showed severe inflammatory cell infiltrates in conjunctivae of mice treated with control MAb, whereas immune mice showed only very mild cellular infiltration. The protective effect of MAb to PNAG was abolished in RAG 1 KO and germ-free mice. Conclusions: Antibodies to both PNAG and alginate demonstrated therapeutic efficacy in models of S. pneumoniae, S. aureus, and P. aeruginosa conjunctivitis, validating the protective capacity of antibodies to surface polysaccharides in distinct ocular tissues.


Assuntos
Acetilglucosamina/imunologia , Anticorpos Monoclonais/uso terapêutico , Conjuntivite Bacteriana/prevenção & controle , Infecções Oculares Bacterianas/prevenção & controle , Infecções Pneumocócicas/prevenção & controle , Polissacarídeos Bacterianos/imunologia , Infecções Estafilocócicas/prevenção & controle , Animais , Cápsulas Bacterianas/imunologia , Conjuntivite Bacteriana/imunologia , Conjuntivite Bacteriana/microbiologia , Modelos Animais de Doenças , Infecções Oculares Bacterianas/imunologia , Infecções Oculares Bacterianas/microbiologia , Feminino , Imunoglobulina G/imunologia , Injeções Intraperitoneais , Camundongos , Camundongos Endogâmicos A , Camundongos Endogâmicos C57BL , Infecções Pneumocócicas/imunologia , Infecções Pneumocócicas/microbiologia , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/imunologia , Streptococcus pneumoniae/imunologia
3.
Front Immunol ; 9: 13, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29403495

RESUMO

The recent emergence of the poultry bacterial pathogen Mycoplasma gallisepticum (MG) in free-living house finches (Haemorhous mexicanus), which causes mycoplasmal conjunctivitis in this passerine bird species, resulted in a rapid coevolutionary arms-race between MG and its novel avian host. Despite extensive research on the ecological and evolutionary dynamics of this host-pathogen system over the past two decades, the immunological responses of house finches to MG infection remain poorly understood. We developed seven new probe-based one-step quantitative reverse transcription polymerase chain reaction assays to investigate mRNA expression of house finch cytokine genes (IL1B, IL6, IL10, IL18, TGFB2, TNFSF15, and CXCLi2, syn. IL8L). These assays were then used to describe cytokine transcription profiles in a panel of 15 house finch tissues collected at three distinct time points during MG infection. Based on initial screening that indicated strong pro-inflammatory cytokine expression during MG infection at the periorbital sites in particular, we selected two key house finch tissues for further characterization: the nictitating membrane, i.e., the internal eyelid in direct contact with MG, and the Harderian gland, the secondary lymphoid tissue responsible for regulation of periorbital immunity. We characterized cytokine responses in these two tissues for 60 house finches experimentally inoculated either with media alone (sham) or one of two MG isolates: the earliest known pathogen isolate from house finches (VA1994) or an evolutionarily more derived isolate collected in 2006 (NC2006), which is known to be more virulent. We show that the more derived and virulent isolate NC2006, relative to VA1994, triggers stronger local inflammatory cytokine signaling, with peak cytokine expression generally occurring 3-6 days following MG inoculation. We also found that the extent of pro-inflammatory interleukin 1 beta signaling was correlated with conjunctival MG loads and the extent of clinical signs of conjunctivitis, the main pathological effect of MG in house finches. These results suggest that the pathogenicity caused by MG infection in house finches is largely mediated by host pro-inflammatory immune responses, with important implications for the dynamics of host-pathogen coevolution.


Assuntos
Doenças das Aves/imunologia , Conjuntivite Bacteriana/imunologia , Citocinas/análise , Citocinas/biossíntese , Tentilhões/imunologia , Mycoplasma gallisepticum/imunologia , Animais , Doenças das Aves/microbiologia , Doenças Transmissíveis Emergentes/microbiologia , Doenças Transmissíveis Emergentes/veterinária , Túnica Conjuntiva/microbiologia , Túnica Conjuntiva/patologia , Conjuntivite Bacteriana/microbiologia , Citocinas/genética , Feminino , Tentilhões/microbiologia , Interações Hospedeiro-Parasita/imunologia , Masculino , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Transdução de Sinais/genética
4.
Artigo em Inglês | MEDLINE | ID: mdl-29380707

RESUMO

BACKGROUND: Bacterial conjunctivitis is a common reason for children to be seen in pediatric practices. A correct diagnosis is important so that appropriate treatment can be instituted. OBJECTIVE: To provide an update on the evaluation, diagnosis, and treatment of bacterial conjunctivitis in children. METHODS: A PubMed search was completed in Clinical Queries using the key term "bacterial conjunctivitis". Patents were searched using the key term "bacterial conjunctivitis" from www.freepatentsonline.com and www.google.com/patents. RESULTS: In the neonatal period, bacterial conjunctivitis is rare and the most common cause of organism is Staphylococcus aureus, followed by Chlamydia trachomatis. In infants and older children, bacterial conjunctivitis is most often caused by Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis. Clinically, bacterial conjunctivitis is characterized by a purulent eye discharge, or sticky eyes on awakening, a foreign body sensation and conjunctival injection (pink eye). The diagnosis is made clinically. Cultures are unnecessary. Some authors suggest a watchful observation approach as most cases of bacterial conjunctivitis are self-limited. A Cochrane review suggests the use of antibiotic eye drops is associated with modestly improved rates of clinical and microbiological remission as compared to the use of placebo. Various investigators have also disclosed patents for the treatment of conjunctivitis. CONCLUSION: The present consensus supports the use of topical antibiotics for bacterial conjunctivitis. Topical antibiotics shorten the course of the disease, reduce discomfort, prevent person-to-person transmission and reduce the rate of reinfection.


Assuntos
Antibacterianos/uso terapêutico , Chlamydia trachomatis/imunologia , Conjuntivite Bacteriana/diagnóstico , Haemophilus influenzae/imunologia , Soluções Oftálmicas/uso terapêutico , Staphylococcus aureus/imunologia , Criança , Conjuntivite Bacteriana/imunologia , Conjuntivite Bacteriana/terapia , Humanos , Lactente , Patentes como Assunto
5.
Infect Immun ; 85(4)2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28115508

RESUMO

Leptospirosis is potentially a fatal zoonosis acquired by contact of skin and mucosal surfaces with soil and water contaminated with infected urine. We analyzed the outcome of infection of C3H/HeJ mice with Leptospira interrogans serovar Copenhageni using an enzootic mode of transmission, the conjunctival route. Infection led to weight loss and L. interrogans dissemination from blood to urine, and spirochetes were detected in blood and urine simultaneously. The infectious dose that led to consistent dissemination to kidney after conjunctival infection was ∼108 leptospires. Interestingly, a lower number of spirochetes appeared to colonize the kidney, given that we quantified ∼105 and ∼10 leptospires per µl of urine and per µg of kidney, respectively. Leptospira-specific IgM and IgG were detected at 15 days postinfection, and isotyping of the Ig subclass showed that the total IgG response switched from an IgG1 response to an IgG3 response after infection with L. interrogans Histological periodic acid-Schiff D staining of infected kidney showed interstitial nephritis, mononuclear cell infiltrates, and reduced size of glomeruli. Quantification of proinflammatory immunomediators in kidney showed that keratinocyte-derived chemokine, macrophage inflammatory protein 2, RANTES, tumor necrosis factor alpha, gamma interferon, and interleukin-10 were upregulated in infected mice. We show that the kinetics of disease progression after infection via the ocular conjunctiva is delayed compared with infection via the standard intraperitoneal route. Differences may be related to the number of L. interrogans spirochetes that succeed in overcoming the natural defenses of the ocular conjunctiva and transit through tissue.


Assuntos
Leptospira interrogans , Leptospirose/microbiologia , Leptospirose/transmissão , Soluções Oftálmicas , Animais , Anticorpos Antibacterianos/imunologia , Quimiotaxia de Leucócito/imunologia , Conjuntivite Bacteriana/imunologia , Conjuntivite Bacteriana/microbiologia , Conjuntivite Bacteriana/patologia , Conjuntivite Bacteriana/transmissão , Citocinas/metabolismo , Modelos Animais de Doenças , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Mediadores da Inflamação/metabolismo , Leptospira interrogans/imunologia , Leptospirose/imunologia , Leptospirose/mortalidade , Camundongos , Camundongos Endogâmicos C3H , Nefrite/imunologia , Nefrite/microbiologia , Nefrite/patologia , Soluções Oftálmicas/efeitos adversos
6.
J Glaucoma ; 25(3): 306-11, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25651208

RESUMO

PURPOSE: To investigate latent conjunctival Chlamydia trachomatis (CT) and Bacteroides fragilis (BF) infections as potential risk factors for posttrabeculectomy bleb failure. PATIENTS AND METHODS: This retrospective observational study included 50 primary open-angle glaucoma eyes of 50 patients who were submitted to trabeculectomy without cytostatics from September 2010 to June 2011 and were followed up for at least a year. Preoperatively, conjunctival scrapings were taken and their specimens subjected to polymerase chain reaction, direct fluorescent assay and cell culture testing for CT, and culture for BF on blood agar medium. Serum CT-specific IgG and IgA and tear interleukin (IL)-1ß and IL-8 concentrations were measured with enzyme-linked immunosorbent assay. We defined bleb failure as intraocular pressure >21 mm Hg with antiglaucoma medications, resulting from reduced bleb filtration capacity due to bleb fibrosis, fistula obstruction, flattened bleb, or encapsulated bleb, and no earlier than 2 weeks after surgery. At the time of the reintervention, a scleroconjunctival biopsy was obtained for histopathology (including direct fluorescent assay testing for CT). Eyes were divided into a failure group and a nonfailure group, depending on whether they developed bleb failure (required reintervention) or not within a follow-up year. RESULTS: In the failure group (n=18), the frequencies of detection of CT and BF in conjunctival specimens were 27.8% and 66.7%, respectively, versus 0% and 9.4% in the nonfailure group (n=32). CT and BF were detected in 11.1% and 11.1%, respectively, of scleroconjunctival biopsies. IgG and IgA seropositivity to CT was found in 66.7% and 33.3%, respectively, of the failure group patients, versus 9.4% and 0% of the nonfailure group patients. Tear IL-1ß and IL-8 levels were markedly elevated in the failure group (468.83±80.43 and 107.89±15.11 pg/mL, respectively) versus the nonfailure group (22.34±5.43 and 9.34±2.83 pg/mL, respectively). CONCLUSION: Being a contributor to low-grade conjunctival inflammation, latent conjunctival CT, and BF infections in primary open-angle glaucoma patients represent risk factors for posttrabeculectomy bleb failure.


Assuntos
Bacteroides fragilis/isolamento & purificação , Chlamydia trachomatis/isolamento & purificação , Conjuntivite Bacteriana/complicações , Infecções Oculares Bacterianas/complicações , Glaucoma de Ângulo Aberto/cirurgia , Complicações Pós-Operatórias , Trabeculectomia , Idoso , Anticorpos Antibacterianos/sangue , Infecções por Bacteroides/complicações , Infecções por Bacteroides/diagnóstico , Infecções por Bacteroides/imunologia , Bacteroides fragilis/imunologia , Infecções por Chlamydia/complicações , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/imunologia , Chlamydia trachomatis/imunologia , Conjuntivite Bacteriana/diagnóstico , Conjuntivite Bacteriana/imunologia , Infecções Oculares Bacterianas/diagnóstico , Infecções Oculares Bacterianas/imunologia , Proteínas do Olho/metabolismo , Feminino , Técnica Direta de Fluorescência para Anticorpo , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Interleucina-1beta/metabolismo , Interleucina-8/metabolismo , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Fatores de Risco , Lágrimas/metabolismo , Tonometria Ocular , Falha de Tratamento
7.
PLoS One ; 10(4): e0124820, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25880849

RESUMO

Tests for the presence of pathogen DNA or antibodies are routinely used to survey for current or past infections. In diseases that emerge following a host jump estimates of infection rate might be under- or overestimated. We here examine whether observed rates of infection are biased for a non-focal host species in a model system. The bacterium Mycoplasma gallisepticum is a widespread pathogen in house finches (Haemorhous mexicanus), a fringillid finch, but an unknown proportion of individuals of other songbird species are also infected. Our goal is to determine the extent to which detection of M. gallisepticum DNA or antibodies against the bacteria in a non-fringillid bird species is over- or underestimated using black-capped chickadees Poecile atricapillus, a species in which antibodies against M. gallisepticum are frequently detected in free-living individuals. After keeping black-capped chickadees in captivity for 12 weeks, during which period the birds remained negative for M. gallisepticum, four were inoculated with M. gallisepticum and four were sham inoculated in both eyes to serve as negative controls. Simultaneously we inoculated six house finches with the same isolate of M. gallisepticum as a positive control. All inoculated birds of both species developed infections detectable by qPCR in the conjunctiva. For the 6 weeks following inoculation we detected antibodies in all M. gallisepticum-inoculated house finches but in only three of the four M. gallisepticum-inoculated black-capped chickadees. All house finches developed severe eye lesions but none of the black-capped chickadees did. Modeling the Rapid Plate Agglutination test results of black-capped chickadees shows that the rate of false-positive tests would be not more than 3.2%, while the estimated rate of false negatives is 55%. We conclude that the proportion of wild-caught individuals in which we detect M. gallisepticum-specific antibodies using Rapid Plate Agglutination is, if anything, substantially underestimated.


Assuntos
Anticorpos Antibacterianos/sangue , Doenças das Aves/imunologia , Galinhas/microbiologia , Conjuntivite Bacteriana/veterinária , Tentilhões/microbiologia , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum/patogenicidade , Animais , Anticorpos Antibacterianos/imunologia , Proteínas de Bactérias/imunologia , Doenças das Aves/microbiologia , Conjuntivite Bacteriana/imunologia , Conjuntivite Bacteriana/microbiologia , DNA Bacteriano/análise , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Tentilhões/imunologia , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/transmissão , Mycoplasma gallisepticum/imunologia , Reação em Cadeia da Polimerase
8.
J Exp Zool A Ecol Genet Physiol ; 323(1): 39-51, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25387693

RESUMO

Aggression can alter infectious disease dynamics through two, non-exclusive mechanisms: 1) increasing direct contact among hosts and 2) altering hosts' physiological response to pathogens. Here we examined the latter mechanism in a social songbird by manipulating intraspecific aggression in the absence of direct physical contact. We asked whether the extent of aggression an individual experiences alters glucocorticoid levels, androgen levels, and individual responses to infection in an ecologically relevant disease model: house finches (Haemorhous mexicanus) infected with Mycoplasma gallisepticum (MG). Wild-caught male finches were housed in one of three settings, designed to produce increasing levels of aggression: 1) alone, with no neighbor ("no neighbor"), 2) next to a sham-implanted stimulus male ("sham neighbor"), or 3) next to a testosterone-implanted stimulus male ("testosterone neighbor"). Following one week of social treatment, focal males were experimentally infected with MG, which causes severe conjunctivitis and induces sickness behaviors such as lethargy and anorexia. While social treatment increased aggression as predicted, there were no differences among groups in baseline corticosterone levels, total circulating androgens, or responses to infection. Across all focal individuals regardless of social treatment, pre-infection baseline corticosterone levels were negatively associated with the severity of conjunctivitis and sickness behaviors, suggesting that corticosterone may dampen inflammatory responses in this host-pathogen system. However, because corticosterone levels differed based upon population of origin, caution must be taken in interpreting this result. Taken together, these results suggest that in captivity, although aggression does not alter individual responses to MG, corticosterone may play a role in this disease.


Assuntos
Agressão/fisiologia , Doenças das Aves/microbiologia , Tentilhões/microbiologia , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum/crescimento & desenvolvimento , Androgênios/sangue , Animais , Comportamento Animal , Doenças das Aves/imunologia , Conjuntivite Bacteriana/imunologia , Conjuntivite Bacteriana/microbiologia , Corticosterona/sangue , Tentilhões/imunologia , Masculino , Infecções por Mycoplasma/imunologia , Infecções por Mycoplasma/microbiologia , Meio Social
9.
Physiol Biochem Zool ; 87(2): 257-64, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24642543

RESUMO

When wild animals become infected, they still must cope with the rigors of daily life, and, thus, they still can be exposed to acute stressors. The suite of physiological responses to acute stress includes modifying the innate immune system, but infections can also cause similar changes. We examined the effects of an acute stressor (capture stress) on leukocyte abundance and bacteria-killing ability (BKA) in wild birds (house finches Haemorhous mexicanus) with and without a naturally occurring infection (Mycoplasma gallisepticum) to determine whether infection alters the typical immune response to stress. Birds were captured and bled within 3 min (baseline sample) and then held in paper bags for 2 h and bled again (stress sample). From blood smears made at both time points, we obtained estimates of total white blood cell (WBC) counts and relative numbers of each cell. We also measured BKA of plasma at both time points. In uninfected birds (n = 26), total WBC count decreased by 30% over time, while in infected birds (n = 9), it decreased by 6%. Relative numbers of heterophils did not change over time in uninfected birds but increased in infected birds. Combined with a reduction in lymphocyte numbers, this led to a threefold increase in heterophil-lymphocyte values in infected birds after the stressor, compared to a twofold increase in uninfected birds. There was a nonsignificant tendency for BKA to decline with stress in uninfected birds but not in diseased birds. Collectively, these results suggest that infections can buffer the negative effects of acute stress on innate immunity.


Assuntos
Doenças das Aves/imunologia , Conjuntivite Bacteriana/veterinária , Tentilhões , Imunidade Inata , Contagem de Leucócitos/veterinária , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum/fisiologia , Animais , Doenças das Aves/microbiologia , Conjuntivite Bacteriana/imunologia , Conjuntivite Bacteriana/microbiologia , Georgia , Manobra Psicológica , Masculino , Infecções por Mycoplasma/imunologia , Infecções por Mycoplasma/microbiologia , Estações do Ano , Estresse Fisiológico
10.
Biochem Biophys Res Commun ; 440(4): 551-7, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24099766

RESUMO

We previously showed that Staphylococcus aureus and Pseudomonas aeruginosa stimulate IL-8 expression in human conjunctival epithelial cells through different signal transduction pathways. As in some cell types both the bacteria may induce the release of prostaglandin E2 (PGE2) and PGE2 may affect the expression of IL-8, we aimed at investigating whether in human conjunctival cells infected with S. aureus or P. aeruginosa the activation of IL-8 transcription was mediated by PGE2 and which were the underlying molecular mechanisms. We found that S. aureus, but not P. aeruginosa, triggered IL-8 activation by increasing COX-2 expression and PGE2 levels in a time-dependent manner. Overexpression of nucleotide-binding oligomerization domain-2 (NOD2) resulted to be essential in the enhancement of IL-8 induced by S. aureus. It dramatically activated c-jun NH2-terminal kinase (JNK) pathway which in turn led to COX2 upregulation and ultimately to IL-8 transcription. The full understanding of the S. aureus-induced biochemical processes in human conjunctival epithelium will bring new insight to the knowledge of the molecular mechanisms involved in conjunctiva bacterial infections and develop novel treatment aiming at phlogosis modulation.


Assuntos
Túnica Conjuntiva/imunologia , Conjuntivite Bacteriana/imunologia , Dinoprostona/biossíntese , Interleucina-8/biossíntese , Proteína Adaptadora de Sinalização NOD2/fisiologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus , Linhagem Celular , Túnica Conjuntiva/microbiologia , Ciclo-Oxigenase 2/biossíntese , Ciclo-Oxigenase 2/genética , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Humanos , Interleucina-8/genética , Proteína Adaptadora de Sinalização NOD2/biossíntese , Proteína Adaptadora de Sinalização NOD2/genética , Pseudomonas aeruginosa , Ativação Transcricional
11.
J Biol Chem ; 288(12): 8269-8278, 2013 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-23372160

RESUMO

Acute inflammation that arises during Pseudomonas aeruginosa-induced ocular infection can trigger tissue damage resulting in long term impairment of visual function, suggesting that the appropriate treatment strategy should include the use of anti-inflammatory agents in addition to antibiotics. We recently identified a potential target for modulation during ocular infection, macrophage migration inhibitory factor (MIF). MIF deficiency protected mice from inflammatory-mediated corneal damage resulting from acute bacterial keratitis. To gain a better understanding of the molecular mechanisms of MIF activity, we analyzed the oligomeric states and functional properties of MIF during infection. We found that in human primary corneal cells infected with P. aeruginosa, MIF is primarily in a homotrimeric state. Homotrimeric MIF levels correlated with the severity of infection in the corneas of infected mice, suggesting that the MIF homotrimers were the functionally active form of MIF. During infection, human primary corneal cells released more IL-8 when treated with recombinant, locked MIF trimers than when treated with lower MIF oligomers. MIF promoted P. aeruginosa-induced IL-8 responses via the formation of caveolin-1-rich "signaling hubs" in the corneal cells that led to elevated MAPK p42/p44 activation and sustained inflammatory signaling. These findings suggest that inhibiting homotrimerization of MIF or the functional activities of MIF homotrimers could have therapeutic benefits during ocular inflammation.


Assuntos
Caveolinas/metabolismo , Conjuntivite Bacteriana/metabolismo , Epitélio Corneano/imunologia , Fatores Inibidores da Migração de Macrófagos/metabolismo , Infecções por Pseudomonas/metabolismo , Animais , Células Cultivadas , Conjuntivite Bacteriana/imunologia , Epitélio Corneano/metabolismo , Epitélio Corneano/microbiologia , Humanos , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/fisiologia , Interleucina-8/biossíntese , Sistema de Sinalização das MAP Quinases , Fatores Inibidores da Migração de Macrófagos/fisiologia , Microdomínios da Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Cultura Primária de Células , Estrutura Quaternária de Proteína , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa
12.
Am J Vet Res ; 73(10): 1670-5, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23013196

RESUMO

OBJECTIVE: To evaluate efficacy of a recombinant Moraxella bovis pilin-cytotoxin-Moraxella bovoculi cytotoxin subunit vaccine to prevent naturally occurring infectious bovine keratoconjunctivitis (IBK). ANIMALS: 107 beef steers. PROCEDURES: 2 groups of calves were inoculated SC with an immunostimulating complex (ISCOM) matrix adjuvant (control group; n = 54) or a recombinant M bovis pilin-cytotoxin-M bovoculi cytotoxin subunit antigen with the ISCOM matrix adjuvant (vaccine group; 53); calves received booster injections 21 days later. Calves were examined once weekly for 16 weeks. Investigators and herd managers were not aware of the inoculum administered to each calf throughout the trial. Primary outcome of interest was the cumulative proportion of calves that developed IBK. Serum samples were obtained before inoculation (day 0) and on days 42 and 112. Serum hemolysin-neutralizing titers against native M bovis and M bovoculi cytotoxin were determined. RESULTS: No difference was detected between groups for the cumulative proportion of calves that developed IBK at weeks 8 and 16 after inoculation. Non-IBK-affected calves in the vaccine group had a significantly higher fold change in serum hemolysin-neutralizing titer against native M bovoculi cytotoxin from day 0 to 42 compared to control calves. CONCLUSIONS AND CLINICAL RELEVANCE: The M bovis pilin-cytotoxin-M bovoculi cytotoxin subunit vaccine with the ISCOM matrix adjuvant was not effective at preventing naturally occurring IBK. It is likely that the incorporation of additional protective antigens in a recombinant Moraxella spp subunit vaccine will be required to yield a product that can be used for effective immunization of cattle against IBK.


Assuntos
Vacinas Bacterianas/uso terapêutico , Doenças dos Bovinos/prevenção & controle , Conjuntivite Bacteriana/veterinária , ISCOMs/uso terapêutico , Ceratoconjuntivite Infecciosa/prevenção & controle , Moraxella/imunologia , Infecções por Moraxellaceae/veterinária , Vacinação/veterinária , Animais , Anticorpos Antibacterianos/sangue , Vacinas Bacterianas/genética , Vacinas Bacterianas/imunologia , California , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/microbiologia , Conjuntivite Bacteriana/imunologia , Conjuntivite Bacteriana/microbiologia , Conjuntivite Bacteriana/prevenção & controle , Citotoxinas/genética , Citotoxinas/imunologia , Proteínas de Fímbrias/genética , Proteínas de Fímbrias/imunologia , ISCOMs/imunologia , Ceratoconjuntivite Infecciosa/imunologia , Ceratoconjuntivite Infecciosa/microbiologia , Masculino , Moraxella/genética , Moraxella bovis/genética , Moraxella bovis/imunologia , Infecções por Moraxellaceae/imunologia , Infecções por Moraxellaceae/microbiologia , Infecções por Moraxellaceae/prevenção & controle , Vacinas de Subunidades Antigênicas/genética , Vacinas de Subunidades Antigênicas/imunologia , Vacinas de Subunidades Antigênicas/uso terapêutico , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/uso terapêutico
13.
J Theor Biol ; 306: 73-92, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22726809

RESUMO

The host-pathogen interaction drives infectious disease dynamics at the individual, population and community levels. Here I present and analyze a model of the vertebrate immune response to mycoplasma infections, and use it to identify which pathogen and host immune characteristics drive patterns of Mycoplasma gallisepticum (MG) infections in the house finch (Carpodacus mexicanus) and other passerine birds. I also address which host and pathogen characteristics most affect host infectiousness and survival. These results imply that much of the observed variation in the house finch likely arises from variation among birds in the effectiveness of their non-specific immune response to MG, and that the host and pathogen characteristics most likely to influence host infectiousness and survival are the intrinsic pathogen growth rate, the strength and efficiency of the non-specific immune response and characteristics affecting the effectiveness of the specific response. These findings suggest that molecular-level study of how MG and other mycoplasmas interact with a host's non-specific and inflammatory responses should reveal much about the relationships between host infectiousness, pathogen load, and disease symptoms in these systems.


Assuntos
Doenças das Aves/microbiologia , Conjuntivite Bacteriana/veterinária , Tentilhões/microbiologia , Modelos Imunológicos , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum/fisiologia , Animais , Anticorpos Antibacterianos/sangue , Doenças das Aves/imunologia , Conjuntivite Bacteriana/imunologia , Conjuntivite Bacteriana/microbiologia , Tentilhões/imunologia , Interações Hospedeiro-Patógeno/imunologia , Interações Hospedeiro-Patógeno/fisiologia , Imunidade Inata , Infecções por Mycoplasma/imunologia , Infecções por Mycoplasma/microbiologia , Mycoplasma gallisepticum/imunologia , Mycoplasma gallisepticum/patogenicidade , Virulência
14.
Jpn J Infect Dis ; 65(1): 1-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22274150

RESUMO

The aim of this study was to evaluate the incidence and morbidities of Chlamydia trachomatis infections in newborn infants. Tissue culture and direct immunofluorescence (DIF) tests were used to detect the presence of nasopharyngeal C. trachomatis infection in 35 preterm and 21 healthy term neonates. All infants were followed up clinically for 3 months, and enzyme-linked immunosorbent assay analysis for serum antichlamydial IgG and IgM was performed on day 15 and week 6. Tissue culture and/or DIF studies showed that 10 of the preterm infants (28.57%), but none of the term infants, were C. trachomatis-positive. The sensitivities of DIF and tissue culture were 40% and 70%, respectively, demonstrating the diagnostic superiority of tissue culture tests for detecting C. trachomatis. Only one asymptomatic preterm infant was found to be positive for antichlamydial antibodies at the 6th week. All C. trachomatis-positive infants were given macrolide antibiotics for 14 days. The study showed that male infants were more frequently infected, but types of delivery, mean gestational ages, mean birth weights, and the need for mechanical ventilation were similar in C. trachomatis-infected and uninfected preterm infants. However, the duration of oxygen treatment was longer in infected preterm infants. Clinical conjunctivitis was more frequent in C. trachomatis-infected infants (60%) than in uninfected infants (24%). C. trachomatis-positive infants had pneumonia more frequently; however, all patients with pneumonia were negative for antichlamydial IgM and IgG antibodies. Macrolide treatment for 2 weeks for nasopharyngeal C. trachomatis positivity may have prevented C. trachomatis related pneumonia, but it may not have significantly influenced the risk of pneumonia caused by other agents. Chlamydial infections may lead to early and late respiratory problems in preterm infants. Nasopharyngeal screening may help physicians detect C. trachomatis infections and provide a means of early diagnosis in this vulnerable patient group.


Assuntos
Anticorpos Antibacterianos/sangue , Infecções por Chlamydia/epidemiologia , Chlamydia trachomatis/patogenicidade , Conjuntivite Bacteriana/microbiologia , Anticorpos Antibacterianos/análise , Peso ao Nascer , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/imunologia , Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/imunologia , Conjuntivite Bacteriana/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Técnica Direta de Fluorescência para Anticorpo , Seguimentos , Idade Gestacional , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Incidência , Recém-Nascido , Macrolídeos/uso terapêutico , Masculino , Oxigênio/uso terapêutico , Pneumonia/tratamento farmacológico , Pneumonia/microbiologia , Estudos Prospectivos , Respiração Artificial , Sensibilidade e Especificidade , Fatores de Tempo , Turquia/epidemiologia
15.
Vet Microbiol ; 155(1): 53-61, 2012 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-21885217

RESUMO

Mycoplasma gallisepticum (MG) has become a common cause of conjunctivitis in free-living house finches (Carpodacus mexicanus) since its emergence in the early 1990s. To date, temporal and spatial genotypic variation in MG has been documented, but phenotypic variation in pathogenicity and immunogenicity has not been examined. House finches were inoculated with MG isolates Virginia (VA)1994, California (CA)2006, or North Carolina (NC)2006, which were cultured from free-living house finches with conjunctivitis in 1994, 2006, and 2006, respectively. Infection with NC2006 resulted in the most severe eye lesions, highest pathogen loads, and highest levels of pathogen-specific lachrymal and serum antibodies. Infection with CA2006 caused the least severe eye lesions, lowest pathogen load, and lowest levels of antibodies. A small number of birds in each group developed protracted, severe disease in spite of robust antibody responses, suggesting that immunopathology may contribute to the lesions. Immunoblot analyses indicated that isolates are antigenically similar; thus, there may be partial cross-protection if a house finch encounters two or more strains of MG throughout the course of its lifetime. This study provides evidence that MG strains or strain variants circulating in house finch populations vary in their ability to cause disease, induce antibody responses, and persist in the host.


Assuntos
Doenças das Aves/imunologia , Doenças das Aves/microbiologia , Conjuntivite Bacteriana/veterinária , Tentilhões/microbiologia , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum/imunologia , Mycoplasma gallisepticum/patogenicidade , Animais , Anticorpos Antibacterianos/análise , Anticorpos Antibacterianos/sangue , Carga Bacteriana , Doenças das Aves/patologia , Conjuntivite Bacteriana/imunologia , Conjuntivite Bacteriana/microbiologia , Conjuntivite Bacteriana/patologia , Genótipo , Infecções por Mycoplasma/imunologia , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/patologia , Fatores de Tempo
16.
Artigo em Russo | MEDLINE | ID: mdl-19715216

RESUMO

AIM: Improvement of therapy of chronic ophthalmic infectious diseases during assessment of functioning of different arms of immune system. MATERIALS AND METHODS: Three hundred and fifty patients with chronic red-eye syndrome were tested by immunofluorescence assay on the presence of antigens of herpesviruses, adenoviruses and Chlamydia in samples from conjunctiva. Expression of 11 cytokines' genes was measured in peripheral blood mononuclear cells by reverse transcription polymerase chain reaction. Production of IFN-alpha and IFN-gamma, levels of serum and spontaneously produced interferon as well as level of susceptibility to the range of immunomodulating preparations were measured during study of interferon status in whole blood cells. Study of parameters of cytokine, interferon and immune statuses was performed in 70 patients. Counts of T- and B-lymphocytes, T-helpers, NK-cells as well as level of circulating immune complexes were measured during study of immune status. RESULTS: Antigens of herpes simplex virus and adenoviruses were detected in samples from conjunctiva in 27% (95 persons) and 36% (126 persons) of patients respectively. Enhanced level of expression of several cytokines (IL-2, IL-4) in studied patients compared with healthy volunteers was observed. Expression levels of IL-12 and TNF-alpha mRNAs were, in opposite, in 2 - 3 times lower. Disorder of IFN-alpha and IFN-gamma synthesis on post-transciption level was observed in 60 - 90% of patients. Decrease of absolute numbers of total T-lymphocytes and T-helpers as well as increase of absolute number of NK-cells was noted in 20%, 25%, and 27% of patients respectively. CONCLUSION: Assignment of individually oriented antiviral, antibacterial and immunomodulating therapy allowed to mitigate intensity of clinical symptoms in 30 -60% of patients with chronic persistent infections of anterior segment of eye.


Assuntos
Infecções por Adenovirus Humanos/tratamento farmacológico , Conjuntivite Bacteriana/tratamento farmacológico , Conjuntivite Viral/tratamento farmacológico , Herpes Simples/tratamento farmacológico , Tracoma/tratamento farmacológico , Infecções por Adenovirus Humanos/diagnóstico , Infecções por Adenovirus Humanos/imunologia , Anti-Infecciosos/uso terapêutico , Antígenos Virais/análise , Chlamydia/efeitos dos fármacos , Doença Crônica , Conjuntivite Bacteriana/diagnóstico , Conjuntivite Bacteriana/imunologia , Conjuntivite Viral/diagnóstico , Conjuntivite Viral/imunologia , Citocinas/biossíntese , Herpes Simples/diagnóstico , Herpes Simples/imunologia , Humanos , Fatores Imunológicos/uso terapêutico , Contagem de Linfócitos , Tracoma/diagnóstico
17.
J Wildl Dis ; 41(2): 317-25, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16107666

RESUMO

Conjunctivitis in house finches (Carpodacus mexicanus), caused by Mycoplasma gallisepticum (MG), was first reported in 1994 and, since this time, has become endemic in house finch populations throughout eastern North America. Although the house finch is most commonly associated with MG-related conjunctivitis, MG has been reported from other wild bird species, and conjunctivitis (not confirmed as MG related) has been reported in over 30 species. To help define the host range of the house finch strain of MG and to better understand the effect of MG on other host species, we monitored a community of wild birds for exposure to MG and conducted experimental infections on nine avian species. For the field portion of our study, we conducted a 9-mo survey (August 2001 to April 2002) of wild avian species in a peri-urban environment on the campus of Auburn University. During this time 358 birds, representing 13 different families, were sampled. No clinical signs of mycoplasmosis were observed in any bird. Thirteen species from nine families had positive agglutination reactions for antibodies to MG, but all birds tested negative by polymerase chain reaction (PCR). Three mourning doves were PCR-positive for MG, but antibodies to MG were not detected. In the experimental infections, we exposed seven native avian species and two cage-bird species to MG (May 2000 to June 2002). After exposure, clinical disease was seen in all four species from the family Fringillidae and in eastern tufted titmice (Baeolophus bicolor). In addition, three other species were infected without clinical signs, suggesting that they may represent potential MG reservoirs.


Assuntos
Doenças das Aves/epidemiologia , Conjuntivite Bacteriana/veterinária , Tentilhões , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum/imunologia , Aves Canoras , Animais , Animais Selvagens , Anticorpos Antibacterianos/sangue , Doenças das Aves/imunologia , Doenças das Aves/microbiologia , Conjuntivite Bacteriana/epidemiologia , Conjuntivite Bacteriana/imunologia , Suscetibilidade a Doenças/veterinária , Feminino , Masculino , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/imunologia , Reação em Cadeia da Polimerase/veterinária , Estudos Soroepidemiológicos , Especificidade da Espécie
18.
J Wildl Dis ; 41(2): 326-33, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16107667

RESUMO

Fourteen house finches were reinoculated (re-exposed) with 0.05 ml (3.24x10(5) colony forming units/ml) of Mycoplasma gallisepticum (MG) in the conjunctival sac of each eye. All birds used in this reinoculation study had recovered from previous infection between 27 and 83 days after inoculation. Recovery was based on the absence of clinical signs of conjunctivitis and/ or the inability to detect MG in conjunctival or choanal samples. Birds were maintained in individual cages under controlled environmental conditions at temperature 21-24 C, relative humidity 70%, and a light cycle adjusted to ambient values. They were divided into three groups, (A, B, and C). Five birds each were reinoculated 219 days (7.3 mo, group A) and 314 days (10.47 mo, group B) after the original infection. The final group of four birds was reinoculated at 425 days after experimental infection (14.17 mo, group C). Although the birds were randomly assigned to the three groups, the duration of the disease state (number of days until clinical signs last observed) during initial infection differed: group A mean=37.0+/-SE 4.549, group B mean=63.6+/-SE 6.306, group C mean=42.75+/-SE 2.750; analysis of variance F2,11=8.17, P=0.007. Within 24 hr after reinoculation six of the 14 experimental birds had developed some clinical signs of MG-induced conjunctivitis. At 3 days after reinoculation, 12 of the 14 birds had unilateral or bilateral conjunctivitis. The duration of clinical signs in the reinoculated individuals was significantly shorter than with their previous infection. These results suggest that the birds were able to mount a rapid and strong immune response following re-exposure. However, they were susceptible to reinfection and developed disease, suggesting that reinfection or perhaps even recurrence of infection and disease could occur in the free-ranging population. This may represent an important component in the epidemiology of this disease in house finches.


Assuntos
Doenças das Aves/imunologia , Conjuntivite Bacteriana/veterinária , Tentilhões , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum/imunologia , Testes de Aglutinação/veterinária , Análise de Variância , Animais , Doenças das Aves/epidemiologia , Conjuntivite Bacteriana/epidemiologia , Conjuntivite Bacteriana/imunologia , Suscetibilidade a Doenças/veterinária , Feminino , Masculino , Infecções por Mycoplasma/imunologia , Reação em Cadeia da Polimerase/veterinária , Distribuição Aleatória , Fatores de Tempo
19.
New Microbiol ; 28(4): 369-72, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16386022

RESUMO

Conjunctival swabs taken from a two-month-old kitten showing ocular discharge were found to be positive for Chlamydophila felis by PCR and isolation. The cat was treated with topical 1% tetracycline ophthalmic ointment twice a day for 60 days. At the end of the treatment, the cat showed no ocular signs and conjunctival swabs resulted PCR and isolation negative for C. felis. Forty days later, the ocular discharge recurred and C. felis was isolated from conjunctival swabs taken from both the cat's eyes. Twenty days of doxycycline systemic treatment at 10 mg/kg once daily was started. The treatment resulted in a complete clinical recovery after a few days. C. felis was not isolated or amplified on the 10th day after beginning the treatment. The cat's conjunctival swabs were also PCR and isolation negative on the 10th, 30th, 60th, 90th, 120th and 240th days after the end of therapy.


Assuntos
Infecções por Chlamydophila/veterinária , Chlamydophila/isolamento & purificação , Conjuntivite Bacteriana/veterinária , Administração Tópica , Animais , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Anticorpos Antibacterianos/sangue , Gatos , Chlamydophila/genética , Chlamydophila/imunologia , Infecções por Chlamydophila/tratamento farmacológico , Infecções por Chlamydophila/imunologia , Infecções por Chlamydophila/microbiologia , Túnica Conjuntiva/microbiologia , Conjuntivite Bacteriana/tratamento farmacológico , Conjuntivite Bacteriana/imunologia , Conjuntivite Bacteriana/microbiologia , Doxiciclina/administração & dosagem , Doxiciclina/uso terapêutico , Exsudatos e Transudatos/microbiologia , Masculino , Reação em Cadeia da Polimerase , Tetraciclina/administração & dosagem , Tetraciclina/uso terapêutico
20.
Proc Biol Sci ; 271(1557): 2569-77, 2004 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-15615682

RESUMO

We examine the role of host seasonal breeding, host seasonal social aggregation and partial immunity in affecting wildlife disease dynamics, focusing on the dynamics of house finch conjunctivitis (Mycoplasma gallisepticum (MG) in Carpodacus mexicanus). This case study of an unmanaged emerging infectious disease provides useful insight into the important role of seasonal factors in driving ongoing disease dynamics. Seasonal breeding can force recurrent epidemics through the input of fresh susceptibles, which will clearly affect a wide variety of wildlife disease dynamics. Seasonal patterns of social aggregation and foraging behaviour could change transmission dynamics. We use latitudinal variation in the timing of breeding, and social systems to model seasonal dynamics of house finch conjunctivitis across eastern North America. We quantify the patterns of seasonal breeding, and social aggregation across a latitudinal gradient in the eastern range of the house finch, supplemented with known field and laboratory information on immunity to MG in finches. We then examine the interactions of these factors in a theoretical model of disease dynamics. We find that both forms of seasonality could explain the dynamics of the house finch-MG system, and that these factors could have important effects on the dynamics of wildlife diseases generally. In particular, while either alone is sufficient to create recurrent cycles of prevalence in a population with an endemic disease, both are required to produce the specific semi-annual pattern of disease prevalence seen in the house finch conjunctivitis system.


Assuntos
Doenças das Aves/imunologia , Conjuntivite Bacteriana/veterinária , Transmissão de Doença Infecciosa/veterinária , Tentilhões , Modelos Biológicos , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum , Animais , Doenças das Aves/microbiologia , Doenças das Aves/transmissão , Conjuntivite Bacteriana/imunologia , Conjuntivite Bacteriana/transmissão , Comportamento Alimentar/fisiologia , Geografia , Infecções por Mycoplasma/imunologia , Infecções por Mycoplasma/transmissão , Estações do Ano , Comportamento Sexual Animal/fisiologia , Comportamento Social
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