ABSTRACT
Members of the Paracoccidioides complex are the causative agents of Paracoccidioidomycosis (PCM), a human systemic mycosis endemic in Latin America. Upon initial contact with the host, the pathogen needs to uptake micronutrients. Nitrogen is an essential source for biosynthetic pathways. Adaptation to nutritional stress is a key feature of fungi in host tissues. Fungi utilize nitrogen sources through Nitrogen Catabolite Repression (NCR). NCR ensures the scavenging, uptake and catabolism of alternative nitrogen sources, when preferential ones, such as glutamine or ammonium, are unavailable. The NanoUPLC-MSE proteomic approach was used to investigate the NCR response of Paracoccidioides lutzii after growth on proline or glutamine as a nitrogen source. A total of 338 differentially expressed proteins were identified. P. lutzii demonstrated that gluconeogenesis, ß-oxidation, glyoxylate cycle, adhesin-like proteins, stress response and cell wall remodeling were triggered in NCR-proline conditions. In addition, within macrophages, yeast cells trained under NCR-proline conditions showed an increased ability to survive. In general, this study allows a comprehensive understanding of the NCR response employed by the fungus to overcome nutritional starvation, which in the human host is represented by nutritional immunity. In turn, the pathogen requires rapid adaptation to the changing microenvironment induced by macrophages to achieve successful infection.
ABSTRACT
The NKp30 receptor is one of the three natural cytotoxic receptors reported in NK cells. This receptor is codified by the NCR3 gene, which encodes three isoforms, a consequence of the alternative splicing of exon 4. A greater expression of the three isoforms (A, B, and C), along with low levels of the NKp30 ligand B7H6, has been reported as a positive prognostic factor in different cancer types. Here, in patients with cervical cancer and precursor lesions, we report an altered immune-phenotype, characterized by non-fitness markers, that correlated with increased disease stage, from CIN 1 to FIGO IV. While overall NK cell numbers increased, loss of NKp30+ NK cells, especially in the CD56dim subpopulation, was found. Perforin levels were decreased in these cells. Decreased expression of the NKp30 C isoform and overexpression of soluble B7H6 was found in cervical cancer patients when compared against healthy subjects. PBMCs from healthy subjects downregulated NKp30 isoforms after co-culture with B7H6-expressing tumour cells. Taken together, these findings describe a unique down-modulation or non-fitness status of the immune response in cervical cancer, the understanding of which will be important for the design of novel immunotherapies against this disease.
Subject(s)
Uterine Cervical Neoplasms , Humans , Female , Perforin/genetics , Killer Cells, Natural , Protein Isoforms/genetics , Alternative Splicing , Natural Cytotoxicity Triggering Receptor 3/geneticsABSTRACT
The diagnosis of bovine herpesvirus 5 (BoHV-5) encephalitis is confirmed after death by laboratory methods applied to brain fragments. Alternative methods to confirm ante-mortem diagnosis are important because the disease is not always lethal. The aim of this study was to investigate whether the presence of the virus genome in the cerebrospinal fluid (CSF) detected by polymerase chain reaction (PCR) might be admitted as a method for ante-mortem diagnosis. CSF samples were taken from 14 animals suffering from BoHV-5 encephalitis, diagnosed by characteristic histopathological lesions in the brain and by identification of the virus genome by PCR in different portions of the brain. Virus DNA was detected in the CSF of 21.42% (3/14) of the evaluated animals. Ante-mortem detection of the virus genome in the CSF showed low sensitivity to confirm the diagnosis. The diagnosis is confirmed by a positive result but a negative one does not discard the disease.(AU)
Subject(s)
Animals , Cattle , Herpesvirus 5, Bovine/isolation & purification , Meningoencephalitis/diagnosis , Cerebrospinal Fluid , Polymerase Chain Reaction/veterinaryABSTRACT
Fatal Human herpesvirus 1 (HHV-1) was diagnosed in 12 captive marmosets (Callithrix jacchus and Callithrix penicillata) from metropolitan region of São Paulo, São Paulo State. Clinical signs were variable among the cases, but most affected marmosets presented signs associated with viral epithelial replication: oral, lingual and facial skin ulcers and hypersalivation, and viral replication in the central nervous system: prostration, seizure and aggressive behavior. Consistent microscopic findings were diffuse mild to severe nonsuppurative necrotizing meningoencephalitis with gliosis, vasculitis and neuronal necrosis. Additionally, in the brain, oral cavity, skin, adrenal gland and myoenteric plexus intranuclear inclusion bodies were present. Immunohistochemistry confirmed the presence of the HHV-1 antigen in association with lesions in the brain, oral and lingual mucosa, facial skin, adrenal gland and myoenteric plexus. HHV-1-specific polymerase chain reaction (PCR) analysis of the brain was carried out and the virus was detected in 7/8 infected marmosets. It is concluded that HHV-1 causes widespread fatal infection in marmosets.(AU)
Infecção fatal por Herpesvirus simplex Tipo 1 (HHV-1) foi diagnosticada em 12 saguis de cativeiro (Callithrix jacchus e Callithrix penicillata) provenientes da região metropolitana de São Paulo, Estado de São Paulo. Os sinais clínicos foram variáveis entres os casos, no entanto, a maioria dos saguis afetados apresentavam sinais associados à replicação viral em epitélios: úlceras na cavidade oral, língua e pele da face e hipersalivação, e no sistema nervoso central: prostração, convulsão e comportamento agressivo. Histologicamente, o principal achado foi meningoencefalite necrosante não supurativa difusa, leve a acentuada com gliose, vasculite e necrose neuronal. Inclusões intranucleares também foram observadas em encéfalo, cavidade oral, pele, glândula adrenal e plexo mioentérico. A imuno-histoquímica anti-HHV-1 confirmou a presença do antígeno viral em associação às lesões em encéfalo, mucosa oral e lingual, pele da face, glândula adrenal e plexo mioentérico. Em 7/8 saguis infectados foi detectada a presença de HHV-1 por reação em cadeia da polimerase (PCR) a partir de amostras de encéfalo. Conclui-se que HHV-1 causa uma infecção disseminada e fatal em saguis.(AU)
Subject(s)
Animals , Callithrix/microbiology , Monkey Diseases/physiopathology , Herpesvirus 1, Human/pathogenicity , Polymerase Chain Reaction/veterinaryABSTRACT
The therapeutic action of phosphorylated mannanoligosaccharides (MOS) was investigated regarding its prebiotic activity on enteropathogenic Escherichia coli (EPEC). Diarrhea was induced in dogs by experimental infection with EPEC strains. Then MOS was supplied once a day, in water for 20 days. Immunological (IgA and IgG), hematological (lymphocytes, neutrophils and monocytes) and bacteriological variables (PCR detection of the eae gene of EPEC recovered from stool culture), as well as occurrence of diarrhea were evaluated. All strains caused diarrhea at 24, 48 and 72 h after infection. PCR results indicated that E. coli isolated from stool culture of all infected animals had the eae gene. There was no significant difference among groups as to number of blood cells in the hemogram and IgA and IgG production. MOS was effective in recovering of EPEC-infected dogs since prebiotic-treated animals recovered more rapidly from infection than untreated ones (p < 0.05). This is an important finding since diarrhea causes intense dehydration and nutrient loss. The use of prebiotics for humans and other animals with diarrhea can be an alternative for the treatment and prophylaxis of EPEC infections.(AU)
Subject(s)
Dogs , Biological Assay , Immunoglobulins , Polymerase Chain Reaction , Escherichia coliABSTRACT
A síndrome mielodisplásica (SMD) compreende um grupo heterogêneo de doenças clonais da medula óssea (MO), caracterizadas por vários graus de citopenias periféricas, que pode evoluir para leucemia mielóide aguda (LMA). Tem sido discutida a possibilidade de a SMD ser mediada por mecanismos autoimunes. As células natural killer (NK) poderiam ter um papel na fisiopatologia e progressão da SMD, mas até o momento pouco se sabe sobre o assunto. Estas células são importantes componentes do sistema imune inato e possuem funções realizadas por dois subtipos distintos: as CD56dim são responsáveis pela atividade citotóxica natural contra células tumorais e infectadas por vírus e as CD56bright pela produção de citocinas imunoregulatórias. As funções destas células são controladas por um conjunto de receptores ativadores e inibidores que reconhecem as células alvo e pertencem a três famílias principais: receptores de citotoxicidade natural (NCR), lectina tipo C e receptores de células assassinas semelhantes a imunoglobulinas (KIR). O objetivo foi estudar alterações do comportamento das células NK em pacientes com SMD. Como a SMD é mais frequente em idosos e relativamente rara na infância, primeiramente foram avaliados os parâmetros de interesse em crianças, adultos e idosos saudáveis. Foi observada nos idosos saudáveis uma redução de expressão de receptores ativadores da família NCR em células NK e aumento da expressão de receptores da família KIR no subtipo CD56bright. As crianças apresentaram alterações semelhantes. Houve redução da expressão de NKG2D nos linfócitos T de idosos. A análise do genótipo KIR revelou que KIR2DL5 e KIR2DS3 estavam associados aos idosos...
Myelodysplastic syndrome (MDS) comprise a heterogeneous group of clonal disorders of bone marrow (BM), characterized by varying degrees of peripheral cytopenias that can develop into acute myeloid leukemia (AML). Recently, has been discussed the possibility that MDS may be mediated by autoimmune mechanisms. Natural killer cells (NK) cells could play a role in the pathophysiology and progression of MDS, but so far little is known about the subject. These cells are important components of the innate immune system and its functions are performed by two distinct subtypes: the CD56dim cells are responsible for natural cytotoxicity against tumor and cells virally infected while CD56bright cells are in charge by production of immunoregulatory cytokines. The functions of these cells are controlled by a set of inhibitory and activating receptors that recognize the target cells. There are three main families of NK cells receptors: natural cytotoxicity receptors (NCR), C-type lectin receptors and killer cell immunoglobulin-like receptors (KIR). The objective was to study changes in the performance of NK cells in MDS patients. As MDS is more common in the elderly and relatively rare in childhood, firstly the parameters of interest were evaluated in healthy children, adults and elderly. Healthy elderly presented a decrease of expression of activating receptors of NCR family in NK cells and increased expression of KIR receptors in CD56bright subset. Children showed similar results. NKG2D expression was decreased on T cells of elderly. Analysis of KIR genotype revealed that KIR2DL5 and KIR2DS3 were significantly associated with old age. Cytotoxic activity was preserved from childhood through old age, suggesting that the increase of the absolute number of CD56dim , observed in elderly, may represent a compensatory mechanism for the receptor expression alterations. In MDS patients, for the first time, was observed an increase of CD56dim and reduction of CD56bright subsets...
Subject(s)
Humans , Male , Female , Child , Adult , Aged , Aging , Killer Cells, Natural , Myelodysplastic SyndromesABSTRACT
We determined the frequency of hepatitis C virus (HCV) genotypes in anti-HCV seropositive patients in the state of Alagoas, Brazil, by means of nested-reverse transcription-polymerase chain reaction (RT-nested-PCR) followed by restriction fragment length polymorphism (RFLP) of amplified fragments of the 5ïNCR. The nested-PCR with genotype-specific primers from the core region was carried out when detection was not possible by the first approach. Detectable HCV-RNA was present in 115 (74.7 percent) of 154 serum samples. Genotype 1 was the most frequent (77.4 percent), against 20.9 percent of genotype 3 and 0.8 percent of genotype 2. Subtype 1b was predominant (65.2 percent), followed by subtypes 1a (8.7 percent), and 3a (6.1 percent). Coinfection (1a/3a) was detected in 0.8 percent of the samples. Indeed, there was no significant differences in the prevalence of genotype 1 compared to what has been obtained from anti-HCV seropositive patients from other locations in Brazil. Here we report for the first time the genotype 2 in the state of Alagoas.
A frequência de genótipos do vírus da hepatite C (HCV) em pacientes soropositivos anti-HCV no estado de Alagoas, Brasil, foi determinada através da RT-PCR aninhada da região 5'NCR seguida pela análise do polimorfismo de comprimento dos fragmentos de restrição (RFLP). A RT-PCR aninhada utilizando primers genótipo-específicos da região core foi efetuada quando não foi possível determinar o genótipo pelo primeiro método. Níveis detectáveis de HCV-RNA estavam presentes em 115 (74,7 por cento) das 154 amostras de soro. O genótipo 1 foi o mais freqüente (77,4 por cento), contra 20,9 por cento do genótipo 3 e 0,8 por cento do genótipo 2. O subtipo 1b foi predominante (65,2 por cento), seguido pelos subtipos 1a (8,7 por cento) e 3a (6,1 por cento). Co-infecção (1a/3a) foi detectada em 0,8 por cento das amostras. Não foram encontradas diferenças significativas quanto à prevalência do genótipo 1 em relação ao que tem sido obtido de pacientes soropositivos anti-HCV de outras localidades do Brasil. Este é o primeiro relato da presença do genótipo 2 no estado.
Subject(s)
Humans , Gene Frequency , Genotype , Hepacivirus/isolation & purification , In Vitro Techniques , Polymerase Chain Reaction , Polymorphism, Genetic , Virus Diseases , Hepatitis Viruses , Critical Pathways , Methods , Patients , Serotyping , MethodsABSTRACT
We determined the frequency of hepatitis C virus (HCV) genotypes in anti-HCV seropositive patients in the state of Alagoas, Brazil, by means of nested-reverse transcription-polymerase chain reaction (RT-nested-PCR) followed by restriction fragment length polymorphism (RFLP) of amplified fragments of the 5´NCR. The nested-PCR with genotype-specific primers from the core region was carried out when detection was not possible by the first approach. Detectable HCV-RNA was present in 115 (74.7%) of 154 serum samples. Genotype 1 was the most frequent (77.4%), against 20.9% of genotype 3 and 0.8% of genotype 2. Subtype 1b was predominant (65.2%), followed by subtypes 1a (8.7%), and 3a (6.1%). Coinfection (1a/3a) was detected in 0.8% of the samples. Indeed, there was no significant differences in the prevalence of genotype 1 compared to what has been obtained from anti-HCV seropositive patients from other locations in Brazil. Here we report for the first time the genotype 2 in the state of Alagoas.
ABSTRACT
We determined the frequency of hepatitis C virus (HCV) genotypes in anti-HCV seropositive patients in the state of Alagoas, Brazil, by means of nested-reverse transcription-polymerase chain reaction (RT-nested-PCR) followed by restriction fragment length polymorphism (RFLP) of amplified fragments of the 5´NCR. The nested-PCR with genotype-specific primers from the core region was carried out when detection was not possible by the first approach. Detectable HCV-RNA was present in 115 (74.7%) of 154 serum samples. Genotype 1 was the most frequent (77.4%), against 20.9% of genotype 3 and 0.8% of genotype 2. Subtype 1b was predominant (65.2%), followed by subtypes 1a (8.7%), and 3a (6.1%). Coinfection (1a/3a) was detected in 0.8% of the samples. Indeed, there was no significant differences in the prevalence of genotype 1 compared to what has been obtained from anti-HCV seropositive patients from other locations in Brazil. Here we report for the first time the genotype 2 in the state of Alagoas.
A frequência de genótipos do vírus da hepatite C (HCV) em pacientes soropositivos anti-HCV no estado de Alagoas, Brasil, foi determinada através da RT-PCR aninhada da região 5'NCR seguida pela análise do polimorfismo de comprimento dos fragmentos de restrição (RFLP). A RT-PCR aninhada utilizando primers genótipo-específicos da região core foi efetuada quando não foi possível determinar o genótipo pelo primeiro método. Níveis detectáveis de HCV-RNA estavam presentes em 115 (74,7%) das 154 amostras de soro. O genótipo 1 foi o mais freqüente (77,4%), contra 20,9% do genótipo 3 e 0,8% do genótipo 2. O subtipo 1b foi predominante (65,2%), seguido pelos subtipos 1a (8,7%) e 3a (6,1%). Co-infecção (1a/3a) foi detectada em 0,8% das amostras. Não foram encontradas diferenças significativas quanto à prevalência do genótipo 1 em relação ao que tem sido obtido de pacientes soropositivos anti-HCV de outras localidades do Brasil. Este é o primeiro relato da presença do genótipo 2 no estado.
ABSTRACT
Las células NK exhiben actividad espontánea contra células tumorales o células infectadas, particularmente por virus. Ellas se caracterizan por la expresión de las moléculas CD16 y CD56, y se subdividen en dos poblaciones, CD16Low/CD56Hi y CD16Hi/CD56Low, que difieren en las citoquinas que producen y en la capacidad citotóxica. La activación de las células NK está regulada por la expresión de receptores inhibidores y activadores que interactúan con diferentes ligandos de las células blanco. La actividad efectora de estas células incluye la lisis de las células blanco por diferentes mecanismos y la producción de citoquinas; las células NK participan por medio de estos factores solubles en diversos procesos fisiológicos, como la hematopoyesis y la regulación de otras células del sistema inmune. Durante la infección por el VIH-1, las células NK ayudan al control de la replicación viral tanto por mecanismos citotóxicos como por la producción de citoquinas, particularmente beta-quimoquinas. Sin embargo, el VIH-1 ha desarrollado mecanismos para evadir la respuesta antiviral mediada por las células NK. Adicionalmente, esta infección induce anormalidades cuantitativas y funcionales en estas células que puedenpresentarse muy temprano en la evolución de la enfermedad y que hacen parte de la inmunosupresión severa característica del SIDA.