RESUMEN
The clinical manifestations of cutaneous leishmaniasis (CL) depend not only on the infecting species involved, but also on the immune response of the individual. Although not yet well understood in humans, parasite survival and persistence are related to the cytokine profile and T cell proliferation, with the Th1 profile being related to cure, and the Th2 profile to disease progression. Considering the need for studies focused on the species with the highest circulation in the state of Amazonas, this study aimed to analyze the immunoregulation stimulated by soluble antigens (SLAs) of Leishmania (L.) amazonensis and Leishmania (V.) guyanensis in human lymphocytes in vitro, in order to understand the immune response of patients with CL. Lymphoproliferation was evaluated against stimuli of SLAs from L. amazonensis (100 µg/mL), SLAs from L. guyanensis (100 µg/mL) and phytohemagglutinin (10 µg/mL) using a BrdU Cell Proliferation ELISA kit after 72 h of incubation. Quantification of the cytokines IL-1b, IL-6, IL-8, IL-10, IL-12 and TNF was performed using the BD™ cytometric bead array human Th1/Th2/Th17 cytokine kit. Our results demonstrated that soluble antigens from L. amazonensis and L. guyanensis stimulated the lymphoproliferation of PBMCs from patients primo-infected with CL. Among the cytokines dosed, the highest concentrations were of IL-6 and IL-8, thus demonstrating that the soluble antigens evaluated are capable of inducing regulatory mechanisms.
Asunto(s)
Antígenos de Protozoos , Proliferación Celular , Citocinas , Humanos , Antígenos de Protozoos/inmunología , Citocinas/inmunología , Proliferación Celular/efectos de los fármacos , Leishmaniasis Cutánea/inmunología , Adulto , Linfocitos/inmunología , Ensayo de Inmunoadsorción Enzimática , Masculino , Femenino , Leishmania guyanensis/inmunología , Adulto JovenRESUMEN
BACKGROUND: Brazil requires the performance of both a test for hepatitis B surface antigen (HBsAg) and a test for antibodies to the core of hepatitis B for blood donor screening. Blood centres in regions of high HBV endemicity struggle to maintain adequate stocks in face of the high discard rates due to anti-HBc reactivity. We evaluated the potential infectivity of donations positive for anti-HBc in search of a rational approach for the handling of these collections. STUDY DESIGN AND METHODS: We tested anti-HBc reactive blood donations from the state of Amazonas for the presence of HBV DNA and for titres of anti-HBs. The study population consists of village-based donors from the interior of Amazonas state. RESULTS: Among 3600 donations, 799 were anti-HBc reactive (22·2%). We were able to perform real-time PCR for the HBV S gene on specimens from 291 of these donors. Eight of these samples were negative for HBsAg and positive for HBV DNA and were defined as occult B virus infections (2·7%). Six of those eight specimens had anti-HBs titres above 100 mIU/ml, indicating the concomitant presence of the virus with high antibody titres. CONCLUSION: A small proportion of anti-HBc reactive donors carry HBV DNA and anti-HBs testing is not useful for predicting viremia on them. This finding indicates the possibility of HBV transmission from asymptomatic donors, especially in areas of high HBV prevalence. Sensitive HBV DNA nucleic acid testing may provide another level of safety, allowing eventual use of anti-HBc reactive units in critical situations.
Asunto(s)
Donantes de Sangre , Transfusión Sanguínea/métodos , Control de Enfermedades Transmisibles/métodos , Hepatitis B/sangre , Hepatitis B/epidemiología , Adulto , Transfusión Sanguínea/normas , Brasil/epidemiología , ADN Viral/sangre , ADN Viral/aislamiento & purificación , Anticuerpos contra la Hepatitis B/sangre , Antígenos del Núcleo de la Hepatitis B/inmunología , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Reacción en Cadena en Tiempo Real de la Polimerasa , Viremia/sangreRESUMEN
Leprosy displays a wide clinical spectrum that is dependent of the type of immune response. We investigate here whether polymorphisms in the promoter region of the IL12RB2 gene are associated with susceptibility or resistance to clinical forms of leprosy. Nucleotide sequencing of the promoter region of IL12RB2 encompassing SNPs -1035 A/G, -1033 T/C, -1023 A/G, -650 del/G and -464 A/G was performed on DNA samples from 105 leprosy patients and 108 healthy controls. However, none of the SNPs were associated with susceptibility to the disease or any of its clinical forms. Similarly, haplotype analysis did not show any association. The haplotype -1035A/-1033T/-650G/-464A was prevalent, and homozygosity for this haplotype was associated to a lower distribution of CD4(+) T cells (p=0.041). Our data suggest that polymorphisms present in the promoter region of IL12RB2 may not be associated with susceptibility to leprosy or its clinical forms.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Lepra/genética , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Receptores de Interleucina-12/genética , Adolescente , Adulto , Anciano , Brasil , Recuento de Linfocito CD4 , Linfocitos T CD4-Positivos/patología , Estudios de Casos y Controles , Susceptibilidad a Enfermedades , Femenino , Frecuencia de los Genes , Haplotipos , Homocigoto , Humanos , Lepra/inmunología , Lepra/patología , Masculino , Persona de Mediana EdadRESUMEN
Polymorphisms present in the first intron of IFN-γ may have an important role in the regulation of the immune response, which could have functional consequences for gene transcription. Leprosy patients are characterized by different immune responses in different clinical forms. We investigated a possible association of the +874 polymorphism and CA repeats present in the first intron of IFN-γ with susceptibility to leprosy and with the manifestation of the different clinical forms. Nucleotide sequencing was performed with samples from 108 leprosy patients and 113 controls subjects, as well as immunophenotyping of CD(4)(+), CD(8)(+) and CD(69)(+) T cells by flow cytometry. The data showed that there were no significant differences between patients and control subjects, as well as according classification of Ridley-Jopling. However, the A/A genotype was significantly increased in paucibacillary patients (p=0.028) and the microsatellite encoding 16 CA repeats were significantly associated with paucibacillary compared to multibacillary patients (p=0.019). Individuals homozygous for the +874 A allele, the mean level of CD(4)(+) and CD(69)(+) T cells was higher. Our data suggest that polymorphisms present in the first intron of IFN-γ are not associated with susceptibility to leprosy, nevertheless, the +874 polymorphism and the CA repeats number encoded in IFN-γ gene may be related to a higher cellular immune response in patients and are consistently more frequently detected in PB patients.
Asunto(s)
Predisposición Genética a la Enfermedad , Interferón gamma/genética , Lepra/genética , Lepra/prevención & control , Repeticiones de Microsatélite/genética , Polimorfismo de Nucleótido Simple/genética , Adolescente , Adulto , Anciano , Alelos , Biomarcadores/metabolismo , Brasil , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes/genética , Humanos , Subgrupos Linfocitarios/inmunología , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Few studies have reported the molecular epidemiological characterization of HIV-1 in the Northern region of Brazil. The present study reports the molecular and epidemiological characterization of 31 HIV-1 isolates from blood donors from the State of Amazonas who donated blood between April 2006 and March 2007. Serum/plasma samples from all donors were screened for HIV antibodies by ELISA and the results confirmed by Western blot analysis. Genomic DNA was extracted from the buffy coat using the Super Quik-Gene-DNA Isolation kit. Nested PCR was performed on the env, gag, and pol regions of HIV-1 using the Gene Amp PCR System 9700. Sequencing reactions were performed using the inner PCR primers and the DYEnamic™ ET Dye Terminator Kit, and phylogenetic analysis was performed using the gag, pol, and env gene sequences. We collected samples from 31 blood donors who tested positive for HIV-1 in confirmatory experiments. The male:female ratio of blood donors was 3.4:1, and the mean age was 32.4 years (range: 19 to 61 years). Phylogenetic analysis showed that subtype B is the most prevalent among Northern Brazilian HIV-1-seropositive blood donors. One HIV-1 subtype C and one circulating recombinant form (CRF_BF) of HIV-1 were identified in the State of Amazonas. This is the first study showing the occurrence of a possible "homogenous" subtype C in this region of Brazil. This finding could contribute to a better characterization of the HIV-1 strains that circulate in the country.
Asunto(s)
Adulto , Femenino , Humanos , Persona de Mediana Edad , Adulto Joven , Donantes de Sangre , Infecciones por VIH/virología , VIH-1 , Secuencia de Bases , Western Blotting , Brasil/epidemiología , Ensayo de Inmunoadsorción Enzimática , Genes env/genética , Genes gag/genética , Genes pol/genética , Infecciones por VIH/epidemiología , VIH-1 , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la PolimerasaRESUMEN
Few studies have reported the molecular epidemiological characterization of HIV-1 in the Northern region of Brazil. The present study reports the molecular and epidemiological characterization of 31 HIV-1 isolates from blood donors from the State of Amazonas who donated blood between April 2006 and March 2007. Serum/plasma samples from all donors were screened for HIV antibodies by ELISA and the results confirmed by Western blot analysis. Genomic DNA was extracted from the buffy coat using the Super Quik-Gene-DNA Isolation kit. Nested PCR was performed on the env, gag, and pol regions of HIV-1 using the Gene Amp PCR System 9700. Sequencing reactions were performed using the inner PCR primers and the DYEnamic™ ET Dye Terminator Kit, and phylogenetic analysis was performed using the gag, pol, and env gene sequences. We collected samples from 31 blood donors who tested positive for HIV-1 in confirmatory experiments. The male:female ratio of blood donors was 3.4:1, and the mean age was 32.4 years (range: 19 to 61 years). Phylogenetic analysis showed that subtype B is the most prevalent among Northern Brazilian HIV-1-seropositive blood donors. One HIV-1 subtype C and one circulating recombinant form (CRF_BF) of HIV-1 were identified in the State of Amazonas. This is the first study showing the occurrence of a possible "homogenous" subtype C in this region of Brazil. This finding could contribute to a better characterization of the HIV-1 strains that circulate in the country.
Asunto(s)
Donantes de Sangre , Infecciones por VIH/virología , VIH-1/genética , Adulto , Secuencia de Bases , Western Blotting , Brasil/epidemiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Genes env/genética , Genes gag/genética , Genes pol/genética , Infecciones por VIH/epidemiología , VIH-1/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Adulto JovenRESUMEN
The rational of this study we intended to investigate whether the peripheral blood immunological/virological biomarkers were associated with distinct patterns of sleeping quality in patients with chronic hepatitis C-(HCV). Distinct well-established indexes/scores were used to categorize the sleeping quality of HCV patients, including the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale and Fatigue Severity Scores. Our findings demonstrated that HCV patients classified as 'good sleeper' displayed an enhanced frequency of circulating CD8(+) T cells, lower frequency of activated (CD69(+)) neutrophils and eosinophils but enhanced frequency of activated lymphocytes besides lower seric levels of IL-4/IL-8/IL-10 but higher levels of IL-12, besides lower HCV virus load and lower anti-HCV IgG levels. In contrast, HCV patients classified as 'poor sleeper' displayed enhanced levels of activated neutrophils and eosinophils but lower frequency of activated lymphocytes, higher seric levels of IL-6/TNF-α/IL-10 but lower levels of IL-12 besides higher HCV virus load and increased anti-HCV IgG levels. Positive correlation was further confirmed by the relationship between the leucocyte activation status, the cytokine levels, the HCV viral load and the anti-HCV IgG reactivity with the PSQI indexes. Analysis of cytokine signature curves demonstrated that lower frequency of IL-10 was observed in HCV patients classified as 'good sleepers', whereas enhanced frequency of IL-6 was found HCV patients classified as 'poor sleepers'. In conclusion, our data suggest that immunological biomarkers (leucocytes activation status and seric cytokines levels) are likely to be associated with sleeping quality patterns in HCV patients, suggesting their putative use for clinical monitoring purposes.
Asunto(s)
Hepacivirus/inmunología , Hepatitis C Crónica/sangre , Trastornos del Sueño-Vigilia/sangre , Adulto , Anciano , Biomarcadores/sangre , Citocinas/genética , Citocinas/inmunología , Femenino , Citometría de Flujo , Hepatitis C Crónica/inmunología , Hepatitis C Crónica/virología , Humanos , Inmunofenotipificación , Masculino , Persona de Mediana Edad , ARN Viral/química , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Trastornos del Sueño-Vigilia/inmunología , Trastornos del Sueño-Vigilia/virología , Subgrupos de Linfocitos T/inmunología , Linfocitos T/inmunología , Adulto JovenRESUMEN
Experimental toxocariasis was used as a model of eosinophil migration. Mice inoculated with 200 Toxocara canis eggs were treated with the leukotriene inhibitor MK886 (1 mg/kg/day). Eosinophils were counted in peripheral blood (PB), peritoneal cavity (PC) and bronchoalveolar lavage fluid (BALF) samples on post-infection days 3, 6, 12, 18, 24 and 36. Eosinophil expression of Mac-1 and VLA-4 was analysed in PB and PC samples. We found that T. canis infection induced systemic eosinophilia from post-infection day 3, peaking on days 6, 12 and 24 in PB, PC and BALF samples respectively. Eosinophilia was more pronounced in PB and PC samples than in BALF samples, and MK886 downregulated eosinophilia to varying degrees in the different sample types. In PB and PC samples, T. canis infection caused early upregulation of Mac-1 with late changes in the VLA-4 profile, whereas MK886 had opposite effects. The distinct time-dependent eosinophilia peaks and differential involvement of leukotrienes in integrin expression demonstrate that, despite the systemic eosinophilia triggered by T. canis infection, inflammatory responses vary by compartment.
Asunto(s)
Eosinofilia/tratamiento farmacológico , Eosinófilos/efectos de los fármacos , Indoles/uso terapéutico , Inhibidores de la Lipooxigenasa/uso terapéutico , Toxocariasis/tratamiento farmacológico , Animales , Líquido del Lavado Bronquioalveolar/citología , Líquido del Lavado Bronquioalveolar/inmunología , Movimiento Celular/efectos de los fármacos , Movimiento Celular/inmunología , Eosinofilia/inmunología , Eosinófilos/inmunología , Femenino , Citometría de Flujo , Integrina alfa4beta1/biosíntesis , Integrina alfa4beta1/efectos de los fármacos , Antígeno de Macrófago-1/biosíntesis , Antígeno de Macrófago-1/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Fenotipo , Toxocariasis/inmunologíaRESUMEN
OBJECTIVE: In the present study, we evaluated the levels of MIP-1alpha and eotaxin and in vivo migration in the peritoneal cavity model, in mice inoculated with live yeast forms of Histoplasma capsulatum or the beta-glucan cell wall component of this fungus, and the influence of a leukotriene biosynthesis inhibitor, MK886, on the release of these chemokines in relation to cell recruitment. MATERIALS: Female outbred Swiss mice (N = 4-5 per group, 3-4 wk, were used. Mice were injected i.p. with 1 ml of the 6 x 10(5) live yeast form of the fungus or with 10 microg of beta-glucan from the cell wall fraction, and treated daily with MK886 (1 mg kg(-1), p.o.) or vehicle. RESULTS: The fungus induced rapid generation of high levels of MIP-1alpha, which remained elevated from 4-48 h whereas very little eotaxin was detected at any time point (Fig. 1A and B). In contrast, the beta-glucan induced a little MIP-1alpha but considerably higher concentrations of eotaxin within the first four hours; however, the level of neither chemokine was sustained (Fig. 2A and B). Treatment of animals with MK886 was effective in reducing the numbers of neutrophils, eosinophils and, to a lesser degree, mononuclear cells accumulating in the peritoneal cavity in response to both the live fungus (Fig. 1C-E) and the cell wall beta-glucan (Fig. 2C-E). CONCLUSIONS: The results suggest that chemokines and leukotrienes may play key roles in the inflammatory cell influx to H. capsulatum infection or to the inoculation of the beta-glucan cell wall component of this fungus
Asunto(s)
Quimiocinas CC/metabolismo , Histoplasma/fisiología , Histoplasmosis/metabolismo , Proteínas Inflamatorias de Macrófagos/metabolismo , beta-Glucanos/administración & dosificación , beta-Glucanos/farmacología , Animales , Pared Celular/química , Quimiocina CCL11 , Quimiocina CCL3 , Quimiocina CCL4 , Quimiocinas/sangre , Femenino , Histoplasmosis/inmunología , Inflamación/inmunología , Inflamación/microbiología , Inflamación/patología , Leucocitos/efectos de los fármacos , Leucotrienos/biosíntesis , Leucotrienos/metabolismo , Ratones , Factores de TiempoRESUMEN
Histoplasma capsulatum is a fungus found intracellularly in neutrophils and peripheral blood mononuclear cells (PBMCs), suggesting that it is capable of evading damage and survives inside these cells. In this study, we report that neutrophils from H. capsulatum-infected mice, and human neutrophils and mononuclear cells exposed to H. capsulatum presented less apoptosis than those from noninfected animals or cells exposed to medium only. Moreover, cells harvested from infected animals are resistant to apoptosis induced by dexamethasone - a proapoptotic stimulant. We also show that neutrophils harvested from infected mice and PBMCs from humans exposed to the fungus had a greatly decreased Mac-1 expression. We conclude that H. capsulatum induces an antiapoptotic state on leucocytes, which correlates with decreased cell-surface Mac-1 expression. These facts may represent an escape mechanism for the fungus by delaying cell death and allowing the fungus to survive inside leucocytes.
Asunto(s)
Apoptosis , Regulación Fúngica de la Expresión Génica , Histoplasma/fisiología , Leucocitos Mononucleares/microbiología , Antígeno de Macrófago-1/biosíntesis , Neutrófilos/microbiología , Animales , Apoptosis/efectos de los fármacos , Quimiotaxis de Leucocito , Dexametasona/farmacología , Femenino , Histoplasmosis/inmunología , Histoplasmosis/patología , Humanos , Leucocitos Mononucleares/metabolismo , Antígeno de Macrófago-1/genética , Ratones , Neutrófilos/metabolismo , Peritonitis/inmunología , Peritonitis/microbiología , Peritonitis/patologíaRESUMEN
The authors analyse daily problems of the nurses' work and the coping strategies used, building knowledge about self care and care of the others in administrative spaces that emphasize freedom and autonomy, relating this (re)construction process to their health process Starting from semi-structured interviews with nurses of a University Hospital, it was possible to identify problems related to human and material resources, team relationship and nurses' own characteristics of subjectivity. There is a perception of greater freedom and autonomy related to administration, although the nurses perceive negative aspects about the boundaries of the freedom exercises, with commitment to the care of the other.
Asunto(s)
Atención de Enfermería , Autocuidado , HumanosRESUMEN
1. The inflammatory cell influx towards the peritoneal cavity in mice inoculated i.p. with live or dead Histoplasma capsulatum or with its subcellular preparations was studied. We also evaluated the effects of dexamethasone (Dexa) or MK886, an inhibitor of leukotriene (LT) biosynthesis, on the recruitment of leukocytes. 2. Live yeast form of fungus (LYH) induced an increase in neutrophils (NE) which was highest 4 to 24 h after inoculation. Mononuclear cell (MN) migration beginning at 24 h with a gradual increase over 48 and 168 h, and an eosinophil (EO) recruitment occurs between 24 and 48 h. 3. NE and EO recruitment induced by dead mycelial form of fungus (DMH) was greater than that observed for dead yeast form of fungus (DYH). A similar leukocyte migration pattern was seen after i.p. injection of the alkali-insoluble fraction (F1) from DYH (F1Y) and F1 from DMH (F1M) this being more active than former. The difference in concentration of beta-glucan in DYH and DMH could explain the different inflammatory capacity exhibited by the two forms of H. capsulatum. 4. LT seems to be the principal mediator of leukocyte migration in response to LYH, DYH or DMH or to beta-glucan. However, other mediators appear to contribute to NE and EO migration since the treatment with Dexa was more effective in inhibiting cell migration than MK886. Complement dependent leukocyte migration may participate in this recruitment. Treatment with MK886 completely abolished MN cell migration, indicating its dependence on the presence of LT.
Asunto(s)
Quimiotaxis de Leucocito , Glucanos/inmunología , Histoplasma/inmunología , Leucocitos/microbiología , Leucotrienos/fisiología , Animales , Antiinflamatorios/farmacología , Pared Celular/inmunología , Pared Celular/metabolismo , Quimiotaxis de Leucocito/efectos de los fármacos , Dexametasona/farmacología , Femenino , Glucanos/metabolismo , Histoplasma/metabolismo , Histoplasmosis/inmunología , Histoplasmosis/microbiología , Indoles/farmacología , Leucocitos/efectos de los fármacos , Antagonistas de Leucotrieno/farmacología , Leucotrienos/biosíntesis , Leucotrienos/metabolismo , Ratones , Infiltración Neutrófila/efectos de los fármacosRESUMEN
Serum and BALF (bronchoalveolar lavage fluid) IL-8 levels and serum levels were investigated in Toxocara canis infected guinea-pigs and the role of IL-5 as a modulator of cytokine secretion was studied. Serum levels increased early in infected animals, exceeding control levels 4 h after infection, peaked between days 6 and 18, and continued to exceed control levels after 48 days of infection. Serum and BALF IL-8 levels showed the same profile as blood eosinophilia, increasing 6 days post-infection and peaking between days 18 and 24. Treatment of infected animals with anti-IL-5 Ab suppressed eosinophilia with a parallel increase in blood IL-8 levels, whereas no change was found in levels. To support our in vivo observation we carried out experiments in vitro using guinea-pig LPS-stimulated adherent peritoneal cells which release large amounts of IL-8 into the supernatants. When rIL-5 was added to LPS-stimulated cells, 65% inhibition of IL-8 release into the supernatants was observed. Pre-incubation of cells with anti-IL-5 Ab prevented the inhibition of IL-8 release into the supernatants induced by rIL-5. Our results demonstrate for the first time that TNF-alpha and IL-8 are released concomitant with or after IL-5 in the eosinophilic inflammation induced by T. canis. Moreover, in addition to showing that IL-5 is fundamental for the induction of blood eosinophilia, the present results suggest that this cytokine may play a new biological role by acting as modulator of IL-8 secretion.