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1.
Med Princ Pract ; : 1-11, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38723618

RESUMO

Breast cancer is the most prevalent cancer among African women, with high mortality rates in Ghana. Nuclear factor kappa B (NF-kB) has been associated with tumor progression in breast cancer. However, its clinical validation is controversial and understudied with no known published data on NF-kB (p65) among breast cancer patients in Ghana and other African countries. This study assessed the prognostic significance of NF-kB (p65) expression and its association with various clinicopathological features in breast cancer patients. Ninety formalin-fixed breast cancer tissues and 15 normal breast tissues were used to determine the expression of NF-kB (p65) using immunohistochemistry. We explored the correlation between expression of NF-kB (p65) and clinicopathological features. NF-kB (p65) was expressed in 86.7% of breast cancer tissues. There was a significant relationship between NF-kB (p65) expression and tumor grade, proliferation index (Ki67), and molecular subtype. High NF-kB (p65) expression in tumor grade 3 was about 10 times that of grade 1 (54.2% vs. 5.1%), and Ki67 > 20 was 79.7% compared to 20.3% for Ki67 ≤ 20. Patients with triple-negative breast cancer (TNBC) had 49.1% overexpression of NF-kB (p65) compared to 17%, 25.4%, and 8.5% for luminal A, luminal B, and HER2 cases, respectively. This study demonstrates that NF-kB (p65) was highly expressed among breast cancer patients at Cape Coast Teaching Hospital, Ghana, especially in TNBC. NF-kB (p65) could serve as a biomarker for cancer stage, progression, prognosis and as a therapeutic target.

2.
BMC Infect Dis ; 21(1): 332, 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33832450

RESUMO

BACKGROUND: Malaria and helminths diseases are co-endemic in most parts of sub-Saharan Africa. Immune responses from each of these pathogens interact, and these interactions may have implications on vaccines. The GMZ2 malaria vaccine candidate is a fusion protein of Plasmodium falciparum merozoite surface protein 3 (MSP3) and glutamate rich protein (GLURP R0). GMZ2 has recently showed modest efficacy in a phase IIb multicenter trial. Here, we assessed the effect of hookworm (Necator americanus) infection and anthelmintic treatment on naturally acquired antibody responses against GMZ2 and constituent antigens. METHODS: This longitudinal cross-sectional study was conducted in the Kintampo North Municipality of Ghana. Blood and stool samples were taken from 158 individuals (4-88 years old) infected with either P. falciparum alone (n = 59) or both hookworm and P. falciparum (n = 63) and uninfected endemic controls (n = 36). Stool hookworm infection was detected by the Kato-Katz method and PCR. Malaria parasitaemia was detected by RDT, light microscopy and P. falciparum-specific 18S rRNA gene PCR. Serum samples were obtained prior to hookworm treatment with a single dose of albendazole (400 mg) and 3 weeks (21 days) after treatment. Levels of IgG1, IgG3 and IgM against GMZ2, MSP3 and GLURP R0 were measured by ELISA and compared among the groups, before and after treatment. RESULTS: Participants with P. falciparum and hookworm co-infection had significantly higher IgG3 levels to GMZ2 than those with only P. falciparum infection and negative control (p < 0.05) at baseline. Treatment with albendazole led to a significant reduction in IgG3 levels against both GMZ2 and GLURP R0. Similarly, IgM and IgG1 levels against MSP3 also decreased following deworming treatment. CONCLUSION: Individuals with co-infection had higher antibody responses to GMZ2 antigen. Treatment of hookworm/malaria co-infection resulted in a reduction in antibody responses against GMZ2 and constituent antigens after albendazole treatment. Thus, hookworm infection and treatment could have a potential implication on malaria vaccine efficacy.


Assuntos
Anti-Helmínticos/uso terapêutico , Anticorpos Antiprotozoários/imunologia , Infecções por Uncinaria/tratamento farmacológico , Vacinas Antimaláricas/imunologia , Malária Falciparum/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Albendazol/uso terapêutico , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos Transversais , Feminino , Infecções por Uncinaria/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Estudos Longitudinais , Vacinas Antimaláricas/genética , Malária Falciparum/parasitologia , Masculino , Pessoa de Meia-Idade , Parasitemia/parasitologia , Proteínas de Protozoários/imunologia , Adulto Jovem
3.
Reprod Health ; 15(1): 140, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30134962

RESUMO

BACKGROUND: The prevalence of exclusive breastfeeding (EBF) for the first six months of life has remained low worldwide and in Ghana, despite strong evidence in support of its practice. This study was aimed at assessing the knowledge and practice of exclusive breastfeeding among mothers in the Tamale metropolis of Ghana. METHODS: In a descriptive cross-sectional study, 393 mother-infant pairs attending child welfare clinics from three health facilities in the Tamale Metropolis were surveyed. A structured item questionnaire was used to collect data on the socio-demographic Characteristics of the participants, their knowledge regarding breastfeeding and level of practice of exclusive breastfeeding (EBF). The results were presented in frequency counts, percentages and inferences were made using a contingency table and chi-square values were computed to check for the relationship between participants demographic characteristics, the Knowledge and the practice of EBF and P value was set at 0.05. RESULTS: The Analysis of the data was done with SPSS version 20. The study surveyed a total of 393 mothers from Tamale metropolis, of whom 27.7% reported having exclusively breastfed their infant for the first 6 months of life. The socio-demographic of the participants showed that they all had some level of education. The study revealed that 39.4% initiated breastfeeding within one hour after birth. Majority of participants had heard of EBF 277 (70.5%), about 344 (87.5%) of participants believed that EBF should be practised for 5 months in their locality. Pearson Chi-square test of the association between sociodemographic characteristics associated and EBF showed a significant association between EBF and the sex of the child, X2 = 4.177, P = .041. Whiles, EBF and the Knowledge on child spacing was X2 = 17.769, P < .001 and EBF and knowledge on Breast cancer reduction was also significant X2 = 4.384, P = .036. CONCLUSIONS: Although all the participants had some level of education background, a majority did not have adequate knowledge on EBF and EBF practice was low in the study community. Thus, we suggest improved education at the child welfare clinics and the media should be used as a platform to educate women adequately about importance of EBF.


Assuntos
Aleitamento Materno/etnologia , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Mães/psicologia , Aleitamento Materno/estatística & dados numéricos , Criança , Estudos Transversais , Feminino , Gana , Humanos , Lactente , Recém-Nascido , Lactação , Masculino , Comportamento Materno , Mães/estatística & dados numéricos , Fatores Socioeconômicos
4.
Malar J ; 16(1): 306, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28764709

RESUMO

BACKGROUND: Recent advances in malaria control efforts have led to an increased number of national malaria control programmes implementing pre-elimination measures and demonstrated the need to develop new tools to track and control malaria transmission. Key to understanding transmission is monitoring the prevalence and immune response against the sexual stages of the parasite, known as gametocytes, which are responsible for transmission. Sexual-stage specific antigens, Pfs230 and Pfs48/45, have been identified and shown to be targets for transmission blocking antibodies, but they have been difficult to produce recombinantly in the absence of a fusion partner. METHODS: Regions of Pfs48/45 and Pfs230 known to contain transmission blocking epitopes, 6C and C0, respectively, were produced in a Lactococcus lactis expression system and used in enzyme linked immunosorbent assays to determine the seroreactivity of 95 malaria patients living in the Central Region of Ghana. RESULTS: Pfs48/45.6C and Pfs230.C0 were successfully produced in L. lactis in the absence of a fusion partner using a simplified purification scheme. Seroprevalence for L. lactis-produced Pfs48/45.6C and Pfs230.C0 in the study population was 74.7 and 72.8%, respectively. CONCLUSIONS: A significant age-dependent increase in antibody titers was observed, which suggests a vaccine targeting these antigens could be boosted during a natural infection in the field.


Assuntos
Vacinas Antimaláricas/imunologia , Malária Falciparum/epidemiologia , Plasmodium falciparum/imunologia , Proteínas de Protozoários/imunologia , Proteínas Recombinantes/imunologia , Adolescente , Adulto , Fatores Etários , Antígenos de Bactérias/análise , Criança , Pré-Escolar , Feminino , Gana/epidemiologia , Humanos , Lactente , Lactococcus lactis/genética , Lactococcus lactis/imunologia , Malária Falciparum/parasitologia , Masculino , Pessoa de Meia-Idade , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Proteínas Recombinantes/genética , Estudos Soroepidemiológicos , Adulto Jovem
5.
Parasitol Res ; 116(6): 1675-1685, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28434050

RESUMO

Toxoplasma gondii is of public health and veterinary importance causing severe diseases in immunocompromised individuals including HIV/AIDS patients and in congenital cases and animals. There is limited information on the epidemiology of T. gondii infection in humans, particularly HIV patients and food animals and the parasite genotypes in Ghana. A total of 394 HIV-infected patients from three hospitals were screened for T. gondii anti-IgG and IgM using ELISA. DNAs from blood samples of seropositve participants and 95 brain tissues of food animals were PCR assayed to detect Toxoplasma gra6. DNA positive samples were genotyped using multilocus nested polymerase chain reaction restriction fragment length polymorphism at 10 loci: sag1, alt.sag2, sag3, btub, gra6, l358, c22-8, c29-2, pk1, and apico. The overall seroprevalence was 74.37% (293/394). Toxoplasma DNAs were detected in 3.07% of the seropositive participants and 9.47% of the animals. Six of the human DNA positive samples were partly typed at sag3: 33.33, 50, and 16.67% isolates had type I, II, and III alleles, respectively. All nine isolates from food animals typed at nine loci except apico were atypical: six isolates were identical to ToxoDB #41 and #145, and one was identical to TgCkBrRj2 all identified in Brazil. The genotype of two isolates has not been reported previously and was named as TgCtGh1. T. gondii seroprevalence is high among the HIV-infected individuals with T. gondii circulating in Ghana being genetically diverse.


Assuntos
Genótipo , Toxoplasmose/epidemiologia , Alelos , Animais , Anticorpos Antiprotozoários , Feminino , Variação Genética , Gana/epidemiologia , Infecções por HIV/complicações , Humanos , Imunoglobulina G , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Prevalência , Estudos Soroepidemiológicos , Toxoplasmose/parasitologia
6.
PLoS One ; 19(6): e0305862, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38924017

RESUMO

Hepatitis B virus (HBV) constitutes a significant global health challenge, with more than 2 billion people infected globally and almost 291 million chronic cases. In Africa, coinfection of HBV with Human Immunodeficiency Virus (HIV) is high, yet the condition remains overlooked in many countries. While antiretroviral therapy (ART) has improved HIV survival, viral hepatitis continues to contribute to morbidity and mortality. Occult Hepatitis B infection (OBI), characterized by a low-level of HBV DNA in individuals with negative hepatitis B surface antigen (HBsAg), is an emerging concern among HIV seropositive individuals due to the risk of HBV reactivation and associated complications, especially hepatocellular carcinoma (HCC). Ghana has an estimated HBV/HIV coinfection prevalence of 13.6% making it important to also determine potential cases of OBI. This study aims to assess OBI prevalence in persons living with HIV (PLHIV). A cross-sectional study was conducted in five health facilities in the Cape Coast Metropolis. HBV-related serological markers were determined among 116 PLHIV using the Enzyme-Linked Immunosorbent Assay (ELISA) method. HBV DNA was extracted from 30 participants found to be HBsAg negative but positive for hepatitis B core antibody (HBcAb+). Nested PCR was employed in detecting HBV DNA and HBV viral load was performed using qPCR. The median age of the participants was 37 years (IQR 22-65). Serologically, 7.8% (n = 9, 95% CI: 3.5-22.7), 12.1% (n = 14), and 25.9% (n = 30) tested positive for solely HBsAg, HBsAb, and HBcAb respectively. OBI prevalence among HBsAg-/HBcAb+ participants was 16.7% (n = 5, 95% CI: 6.5-23.7) with a median HBV DNA level of 139.2 IU/ml (IQR, 96.7-142.0). The prevalence of OBI among HIV-positive participants in the Cape Coast Metropolis highlights the need to consider screening for HBV among HIV patients using nucleic acid amplification tests. This can inform medical management and reduce the risk of liver complications, including HCC.


Assuntos
Coinfecção , Infecções por HIV , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Hepatite B , Humanos , Gana/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/complicações , Infecções por HIV/virologia , Feminino , Masculino , Adulto , Hepatite B/epidemiologia , Hepatite B/complicações , Hepatite B/virologia , Prevalência , Pessoa de Meia-Idade , Estudos Transversais , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Antígenos de Superfície da Hepatite B/sangue , Coinfecção/epidemiologia , Coinfecção/virologia , DNA Viral/sangue , Adulto Jovem
7.
Trop Med Infect Dis ; 6(4)2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34941666

RESUMO

Cryptosporidium species are intestinal protozoan parasites that infect and cause diarrhoea in animals and humans. The current study was conducted to determine the prevalence and risk factors of Cryptosporidium infection among HIV-infected patients in the Central region of Ghana. In this cross-sectional study, four hundred eighteen documented HIV-infected participants from four health facilities that provide antiretroviral therapy (ART) services across the Central region of Ghana were selected by systematic random sampling. An enzyme-linked immunosorbent assay (CoproELISATM, Cryptosporidium Savyon® Diagnostics Ltd., Ashdod, Israel) was used to detect Cryptosporidium antigens in stool samples obtained from participants. Information regarding participants' sociodemographic characteristics and clinical symptoms as well as potential environmental and behavioral risk factors were collected using a structured questionnaire. Chi-square or Fisher's exact tests were used to determine associations between Cryptosporidium infections and explanatory variables, while risk factors were assessed using multivariate logistic regression analysis. The overall prevalence of Cryptosporidium infection among HIV-infected participants in this study was 6.2% (95% CI: 3.90-8.54). Cryptosporidium was not significantly associated with any of the sociodemographic variables, patient clinical symptoms, and environmental factors. However, the prevalence of the parasite was significantly higher 25% (95% CI: 1.17-48.83; p = 0.013) among participants who did not always wash their hands before meals and those who did not always wash vegetables before eating them, 23.5% (95% CI: 1.05-46.01; p = 0.016). Multivariate logistic regression analysis showed that participants who used public water closet facilities were approximately 9 times more likely to become infected with the parasite than those who practised open defecation (OR: 8.83; 95% CI: 1.22-64.13; p = 0.031). In conclusion, Cryptosporidium is prevalent among HIV-infected patients in the Central region of Ghana. An important risk factor identified was the use of the public water closet toilet facility. More attention should be given to ensuring cleanliness at shared water closet facilities in addition to adequate disinfection of hands after using such facilities.

8.
Artigo em Inglês | MEDLINE | ID: mdl-34484390

RESUMO

Phyllanthus urinaria has been characterized for its several biological and medicinal effects such as antiviral, antibacterial, anti-inflammatory, anticancer, and immunoregulation. In recent years, Phyllanthus urinaria has demonstrated potential to modulate the activation of critical pathways such as NF-κB, P13K/AKT, and ERK/JNK/P38/MAPKs associated with cell growth, proliferation, metastasis, and apoptotic cell death. To date, there is much evidence indicating that modulation of cellular signaling pathways is a promising approach to consider in drug development and discovery. Thus, therapies that can regulate cancer-related pathways are longed-for in anticancer drug discovery. This review's focus is to provide comprehensive knowledge on the anticancer mechanisms of Phyllanthus urinaria through the regulation of NF-κB, P13K/AKT, and ERK/JNK/P38/MAPKs signaling pathways. Thus, the review summarizes both in vitro and in vivo effects of Phyllanthus urinaria extracts or bioactive constituents with emphasis on tumor cell apoptosis. The literature information was obtained from publications on Google Scholar, PubMed, Web of Science, and EBSCOhost. The key words used in the search were "Phyllanthus" or "Phyllanthus urinaria" and cancer. P. urinaria inhibits cancer cell proliferation via inhibition of NF-κB, P13K/AKT, and MAPKs (ERK, JNK, P38) pathways to induce apoptosis and prevents angiogenesis. It is expected that understanding these fundamental mechanisms may help stimulate additional research to exploit Phyllanthus urinaria and other natural products for the development of novel anticancer therapies in the future.

9.
BMJ Open ; 11(12): e048551, 2021 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-34857556

RESUMO

OBJECTIVE: The objective of this scoping review was to map the current situation and available evidence and gaps on rabies morbidity, mortality, integrated rabies surveillance programmes, and existing prevention and control strategies in Africa. METHODS: We conducted a systematic scoping review following the Joanna Briggs methodology and Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews checklist. Medline, Embase, CINAHL (EBSCOHost), Scopus, Web of Science and rabies web conferences were used to search for peer-reviewed publications between January 1946 and May 2020. Two researchers reviewed the studies and extracted data based on author (year) and region, study design and data collection duration, participants/comparators, interventions, control conditions/exposures and outcomes (rabies mortality and morbidity) and key findings/gaps/challenges. The results were reported narratively using Arksey and O'Malley's methodological framework. RESULTS: Electronic search yielded 2775 records, of which 43 studies were included. A total of 543 714 bite victims were censored through the included studies. Most of the victims were less than 15 years of age. The studies included rabies morbidity (21) and mortality (15) fluctuating in space and time across Africa depending on countries' rabies prevention and control practices (16). Others were surveillance (nine studies); surveillance and prevention (five studies); management and control (seven studies); and surveillance, prevention and control (six studies). We found challenges in rabies reporting, existing dog vaccination programmes and post-exposure prophylaxis availability or compliance. CONCLUSION: This study found challenges for dog rabies control and elimination in Africa and the need for a policy to drive the goal of zero dog-transmitted rabies to humans by 2030.This is an open-access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build on this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated and the use is non-commercial (see http://creativecommons.org/licenses/by-nc/4.0/).


Assuntos
Mordeduras e Picadas , Raiva , África/epidemiologia , Animais , Mordeduras e Picadas/complicações , Mordeduras e Picadas/epidemiologia , Cães , Morbidade , Profilaxia Pós-Exposição , Raiva/epidemiologia , Raiva/prevenção & controle
10.
PLoS One ; 14(9): e0222382, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31513658

RESUMO

BACKGROUND: The eosinophil cationic protein (ECP) is a cytotoxic protein mainly secreted by eosinophils granulocytes and plays a role in host defense against parasitic infections. Infection with Necator americanus (hookworm) is traditionally diagnosed by the Kato-Katz method which is inherently tedious, subjective and known to underestimate infection intensity. This study aimed to assess levels of serum ECP in relation to hookworm infection intensity. METHODS: Stool samples from 984 (aged 4 to 80 years) participants in a cross-sectional study conducted in the Kintampo North Municipality of Ghana were examined using the Kato-Katz and formol-ether concentration methods. Serum ECP levels were measured by ECP assay kit and compared between 40 individuals infected with hookworm only, 63 with hookworm- Plasmodium falciparum co-infection, 59 with P. falciparum infection and 36 with no infection. RESULTS: Hookworm infection prevalence was 18.1% (178/984). ECP levels were significantly higher in individuals infected with hookworm only (ß = 2.96, 95%CI = 2.69, 3.23, p<0.001) or co-infected with P. falciparum (ß = 3.15, 95%CI = 2.91, 3.39, p<0.001) compared to the negative control. Levels of ECP were similar between those with only P. falciparum infection and the uninfected control (p>0.05). Increased hookworm intensity was associated with a significant increase in ECP level (ß = 4.45, 95%CI = 2.25, 9.11, rs = 0.193, n = 103, p<0.01). ECP threshold of 84.98ng/ml was associated with a positive predictive value (PPV) of 98% (95% CI = 92, 100), and negative predictive value (NPV) of 76% (95% CI = 62, 87) in classifying hookworm infection status with an AUROC of 96.3%. CONCLUSION: Serum ECP level may be a good biomarker of hookworm infection and intensity and warrant further investigations to help improve current hookworm diagnosis.


Assuntos
Proteína Catiônica de Eosinófilo/análise , Infecções por Uncinaria/diagnóstico , Infecções por Uncinaria/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ancylostomatoidea/metabolismo , Ancylostomatoidea/patogenicidade , Animais , Biomarcadores/sangue , Criança , Pré-Escolar , Estudos Transversais , Proteína Catiônica de Eosinófilo/sangue , Fezes/parasitologia , Feminino , Gana/epidemiologia , Infecções por Uncinaria/sangue , Humanos , Malária Falciparum/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência
11.
Clin Vaccine Immunol ; 19(11): 1798-805, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22971780

RESUMO

A number of studies of highly exposed HIV-1-seronegative individuals (HESN) have found HIV-1-specific cellular responses. However, there is limited evidence that responses prevent infection or are linked to HIV-1 exposure. Peripheral blood mononuclear cells (PBMC) were isolated from HESN in HIV-1-discordant relationships and low-risk controls in Nairobi, Kenya. HIV-1-specific responses were detected using gamma interferon (IFN-γ) enzyme-linked immunosorbent spot (ELISpot) assays stimulated by peptide pools spanning the subtype A HIV-1 genome. The HIV-1 incidence in this HESN cohort was 1.5 per 100 person years. Positive ELISpot responses were found in 34 (10%) of 331 HESN and 14 (13%) of 107 low-risk controls (odds ratio [OR] = 0.76; P = 0.476). The median immunodominant response was 18.9 spot-forming units (SFU)/10(6) peripheral blood mononuclear cells (PBMC). Among HESN, increasing age (OR = 1.24 per 5 years; P = 0.026) and longer cohabitation with the HIV-1-infected partner (OR = 5.88 per 5 years; P = 0.003) were associated with responses. These factors were not associated with responses in controls. Other exposure indicators, including the partner's HIV-1 load (OR = 0.99 per log(10) copy/ml; P = 0.974) and CD4 count (OR = 1.09 per 100 cells/µl; P = 0.238), were not associated with responses in HESN. HIV-1-specific cellular responses may be less relevant to resistance to infection among HESN who are using risk reduction strategies that decrease their direct viral exposure.


Assuntos
HIV-1/imunologia , Leucócitos Mononucleares/imunologia , Parceiros Sexuais , Adulto , Fatores Etários , ELISPOT/métodos , Feminino , Infecções por HIV/imunologia , Humanos , Interferon gama/metabolismo , Quênia , Masculino , Fatores de Tempo
12.
J Virol ; 80(5): 2529-38, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16474159

RESUMO

Natural killer (NK) cells are potent effectors of natural immunity and their activity prevents human immunodeficiency virus type 1 (HIV-1) viral entry and viral replication. We sought to determine whether NK immune responses are associated with different clinical course of HIV-1 and HIV-2 infections. A cross-sectional analysis of NK cell responses was undertaken in 30 HIV-1 and 30 HIV-2 subjects in each of three categories of CD4(+)-T-cell counts (>500, 200 to 500, and <200 cells/microl) and in 50 HIV-uninfected control subjects. Lytic activity and gamma interferon (IFN-gamma) secretion were measured by chromium release and enzyme-linked immunospot assays, respectively. Flow cytometry was used to assess intracellular cytokines and chemokines. Levels of NK cytotoxicity were significantly higher in HIV-2 than in HIV-1 infections in subjects with high CD4(+)-T-cell counts and were similar to that of the healthy controls. In these HIV-2 subjects, cytolytic activity was positively correlated to NK cell count and inversely related to plasma viremia. Levels of intracellular MIP-1beta, RANTES, tumor necrosis factor alpha, and IFN-gamma produced by NK CD56(bright) cells were significantly higher in HIV-2- than HIV-1-infected subjects with high CD4(+)-T-cell counts but fell to similar levels as CD4 counts dropped. The data suggest efficient cytolytic and chemokine-suppressive activity of NK cells early in HIV-2 infection, which is associated with high CD4(+) T-cell counts. Enhancement of these functions may be important in immune-based therapy to control HIV disease.


Assuntos
Infecções por HIV/imunologia , HIV-1/imunologia , HIV-2/imunologia , Células Matadoras Naturais/imunologia , Contagem de Linfócito CD4 , Quimiocinas/análise , Estudos Transversais , Citocinas/análise , Testes Imunológicos de Citotoxicidade , Citometria de Fluxo , Humanos , Interferon gama/análise , Viremia
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