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Early identification of patients co-infected with HIV and human T-lymphotropic virus type 1 (HTLV-1) is essential to improve care, as CD4+ T-cell counts have been revealed to be an unreliable laboratory parameter to monitor HIV infection in co-infection. Unfortunately, HTLV-1 testing is not currently available in sub-Saharan Africa. We conducted this study to determine the performance of absolute CD4+ T-cell count estimation in guiding the clinical suspicion of co-infection. A cross-sectional survey was conducted in antiretroviral-naïve HIV (AN-HIV) patients attending an HIV outpatient clinic in Maputo city, Mozambique. Seven hundred and one AN-HIV patients were enrolled in the study. The prevalence of HTLV-1 co-infection was 4.5% (95% confidence interval [CI] 3.0-6.0%). Logistic regression analysis showed that CD4+ T-cell count was an independent predictor of co-infection (P value: 0.000). The performance of absolute CD4+ T-cell counts in predicting co-infection was higher in symptomatic HIV patients when compared with asymptomatic HIV patients. The best performance was achieved with the cut-off of CD4+ count of 500 cells/mm(3), which gave sensitivity, specificity, positive and negative predictive values of 54.2%, 87.2%, 24.0% and 96.2%, respectively. In conclusion, our data provide evidence that the absolute CD4+ T-cell count is of moderate accuracy in guiding the clinical suspicion of co-infection in AN-HIV and its implementation could improve the care provided to a significant number of HIV patients in Mozambique. [ABSTRACT FROM AUTHOR]

Mpox is a zoonotic disease historically reported in Africa. Since 2003, limited outbreaks have occurred outside Africa. In 2022, the global spread of cases with sustained interhuman transmission and unusual disease features raised public health concerns. We explore the mpox outbreak in Rio de Janeiro (RJ) state, Brazil, in an observational study of mpox-suspected cases from June to December 2022. Data collection relied on a public healthcare notification form. Diagnosis was determined by MPXV-PCR. In 46 confirmed cases, anti-OPXV IgG was determined by ELISA, and seven MPXV genomes were sequenced. A total of 3095 cases were included, 816 (26.3%) with positive MPXV-PCR results. Most positive cases were men in their 30 s and MSM. A total of 285 (34.9%) MPXV-PCR+ patients live with HIV. Eight were coinfected with varicella-zoster virus. Anogenital lesions and adenomegaly were associated with the diagnosis of mpox. Females and individuals under 18 represented 9.4% and 5.4% of all confirmed cases, respectively, showing higher PCR cycle threshold (Ct) values and fewer anogenital lesions compared to adult men. Anti-OPXV IgG was detected in 29/46 (63.0%) patients. All analyzed sequences belonged to clade IIb. In RJ state, mpox presented a diverse clinical picture, represented mainly by mild cases with low complication rates and prominent genital involvement. The incidence in females and children was higher than usually reported. The observation of a bimodal distribution of Ct values, with few positive results, may suggest the need to review the diagnostic criteria in these groups., (© 2024 Wiley Periodicals LLC.)

The COVID-19 pandemic has led to the commercialization of many antigen-based rapid diagnostic tests (Ag-RDTs), requiring independent evaluations. This report describes the clinical evaluation of the Novel Coronavirus 2019-nCoV Antigen Test (Colloidal Gold) (Beijing Hotgen Biotech Co., Ltd.), at two sites within Brazil and one in the United Kingdom. The collected samples (446 nasal swabs from Brazil and 246 nasopharyngeal samples from the UK) were analyzed by the Ag-RDT and compared to reverse transcription-quantitative PCR (RT-qPCR). Analytical evaluation of the Ag-RDT was performed using direct culture supernatants of SARS-CoV-2 strains from the wild-type (B.1), Alpha (B.1.1.7), Delta (B.1.617.2), Gamma (P.1), and Omicron (B.1.1.529) lineages. An overall sensitivity and specificity of 88.2% (95% confidence interval [CI], 81.3 to 93.3) and 100.0% (95% CI, 99.1 to 100.0), respectively, were obtained for the Brazilian and UK cohorts. The analytical limit of detection was determined as 1.0 × 10 3 PFU/mL (Alpha), 2.5 × 10 2 PFU/mL (Delta), 2.5 × 10 3 PFU/mL (Gamma), and 1.0 × 10 3 PFU/mL (Omicron), giving a viral copy equivalent of approximately 2.1 × 10 4 copies/mL, 9.0 × 10 5 copies/mL, 1.7 × 10 6 copies/mL, and 1.8 × 10 5 copies/mL for the Ag-RDT, respectively. Overall, while a higher sensitivity was claimed by the manufacturers than that found in this study, this evaluation finds that the Ag-RDT meets the WHO minimum performance requirements for sensitivity and specificity of COVID-19 Ag-RDTs. This study illustrates the comparative performance of the Hotgen Ag-RDT across two global settings and considers the different approaches in evaluation methods. IMPORTANCE Since the beginning of the SARS-CoV-2 pandemic, we have witnessed growing numbers of antigen rapid diagnostic tests (Ag-RDTs) being brought to market. In the United Kingdom, this was somewhat controlled indirectly as the government offered free tests from a small number of companies. However, as this has now ceased, individuals are responsible for their own acquisition of test kits. Similarly in Brazil, as of January 2022, pharmacies and other health care retailers are permitted to sell Ag-RDTs directly to the community. Many of these Ag-RDTs have not been externally evaluated, and results are not readily available to the public. Thus, there is now a need for a transparent evaluation of Ag-RDTs with both analytical and clinical evaluation. We present an independent review of the Novel Coronavirus 2019-nCoV Antigen Test (Colloidal Gold) (Beijing Hotgen Biotech Co., Ltd.), at two sites within Brazil and one in the United Kingdom.

Population surveillance in COVID-19 Pandemic is crucial to follow up the pace of disease and its related immunological status. Here we present a cross-sectional study done in Maricá, a seaside town close to the city of Rio de Janeiro, Brazil. Three rounds of study sampling, enrolling a total of 1134 subjects, were performed during May to August 2021. Here we show that the number of individuals carrying detectable IgG antibodies and the neutralizing antibody (NAb) levels were greater in vaccinated groups compared to unvaccinated ones, highlighting the importance of vaccination to attain noticeable levels of populational immunity against SARS-CoV-2. Moreover, we found a decreased incidence of COVID-19 throughout the study, clearly correlated with the level of vaccinated individuals as well as the proportion of individuals with detectable levels of IgG anti-SARS-CoV-2 and NAb. The observed drop occurred even during the introduction of the Delta variant in Maricá, what suggests that the vaccination slowed down the widespread transmission of this variant. Overall, our data clearly support the use of vaccines to drop the incidence associated to SARS-CoV-2., Competing Interests: The authors have declared that no competing interests exist.

Serological tests detect antibodies generated by infection or vaccination, and are indispensable tools along different phases of a pandemic, from early monitoring of pathogen spread up to seroepidemiological studies supporting immunization policies. This work discusses the development of an accurate and affordable COVID-19 antibody test, from production of a recombinant protein antigen up to test validation and economic analysis. We first developed a cost-effective, scalable technology to produce SARS-COV-2 spike protein and then used this antigen to develop an enzyme-linked immunosorbent assay (ELISA). A receiver operator characteristic (ROC) analysis allowed optimizing the cut-off and confirmed the high accuracy of the test: 98.6% specificity and 95% sensitivity for 11+ days after symptoms onset. We further showed that dried blood spots collected by finger pricking on simple test strips could replace conventional plasma/serum samples. A cost estimate was performed and revealed a final retail price in the range of one US dollar, reflecting the low cost of the ELISA test platform and the elimination of the need for venous blood sampling and refrigerated sample handling in clinical laboratories. The presented workflow can be completed in 4 months from first antigen expression to final test validation. It can be applied to other pathogens and in future pandemics, facilitating reliable and affordable seroepidemiological surveillance also in remote areas and in low-income countries., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 Elsevier B.V. All rights reserved.)

The SARS-CoV-2 pandemic has had a social and economic impact worldwide, and vaccination is an efficient strategy for diminishing those damages. New adjuvant formulations are required for the high vaccine demands, especially adjuvant formulations that induce a Th1 phenotype. Herein we assess a vaccination strategy using a combination of Alum and polyinosinic:polycytidylic acid [Poly(I:C)] adjuvants plus the SARS-CoV-2 spike protein in a prefusion trimeric conformation by an intradermal (ID) route. We found high levels of IgG anti-spike antibodies in the serum by enzyme linked immunosorbent assay (ELISA) and high neutralizing titers against SARS-CoV-2 in vitro by neutralization assay, after two or three immunizations. By evaluating the production of IgG subtypes, as expected, we found that formulations containing Poly(I:C) induced IgG2a whereas Alum did not. The combination of these two adjuvants induced high levels of both IgG1 and IgG2a. In addition, cellular immune responses of CD4 + and CD8 + T cells producing interferon-gamma were equivalent, demonstrating that the Alum + Poly(I:C) combination supported a Th1 profile. Based on the high neutralizing titers, we evaluated B cells in the germinal centers, which are specific for receptor-binding domain (RBD) and spike, and observed that more positive B cells were induced upon the Alum + Poly(I:C) combination. Moreover, these B cells produced antibodies against both RBD and non-RBD sites. We also studied the impact of this vaccination preparation [spike protein with Alum + Poly(I:C)] in the lungs of mice challenged with inactivated SARS-CoV-2 virus. We found a production of IgG, but not IgA, and a reduction in neutrophil recruitment in the bronchoalveolar lavage fluid (BALF) of mice, suggesting that our immunization scheme reduced lung inflammation. Altogether, our data suggest that Alum and Poly(I:C) together is a possible adjuvant combination for vaccines against SARS-CoV-2 by the intradermal route., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 dos-Santos, Firmino-Cruz, da Fonseca-Martins, Oliveira-Maciel, Perez, Roncaglia-Pereira, Dumard, Guedes-da-Silva, Santos, Leandro, Ferreira, Guimarães-Pinto, Conde, Rodrigues, Silva, Alvim, Lima, Marsili, Abreu, Ferreira Jr., Mohana Borges, Tanuri, Souza, Rossi-Bergmann, Vale, Silva, de Oliveira, Filardy, Gomes and de Matos Guedes.)

Chikungunya virus (CHIKV) is a re-emergent arbovirus that causes a disease characterized primarily by fever, rash and severe persistent polyarthralgia, although <1% of cases develop severe neurological manifestations such as inflammatory demyelinating diseases (IDD) of the central nervous system (CNS) like acute disseminated encephalomyelitis (ADEM) and extensive transverse myelitis. Genetic factors associated with host response and disease severity are still poorly understood. In this study, we performed whole-exome sequencing (WES) to identify HLA alleles, genes and cellular pathways associated with CNS IDD clinical phenotype outcomes following CHIKV infection. The cohort includes 345 patients of which 160 were confirmed for CHIKV. Six cases presented neurological manifestation mimetizing CNS IDD. WES data analysis was performed for 12 patients, including the CNS IDD cases and 6 CHIKV patients without any neurological manifestation. We identified 29 candidate genes harboring rare, pathogenic, or probably pathogenic variants in all exomes analyzed. HLA alleles were also determined and patients who developed CNS IDD shared a common signature with diseases such as Multiple sclerosis (MS) and Neuromyelitis Optica Spectrum Disorders (NMOSD). When these genes were included in Gene Ontology analyses, pathways associated with CNS IDD syndromes were retrieved, suggesting that CHIKV-induced CNS outcomesmay share a genetic background with other neurological disorders. To our knowledge, this study was the first genome-wide investigation of genetic risk factors for CNS phenotypes in CHIKV infection. Our data suggest that HLA-DRB1 alleles associated with demyelinating diseases may also confer risk of CNS IDD outcomes in patients with CHIKV infection., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Alves-Leon, Ferreira, Herlinger, Fontes-Dantas, Rueda-Lopes, Francisco, Gonçalves, de Araújo, Rêgo, Higa, Gerber, Guimarães, de Menezes, de Paula Tôrres, Maia, Nogueira, França, da Silva, Naurath, Correia, Vasconcelos, Tanuri, Ferreira, Cardoso, Aguiar and de Vasconcelos.)

Background: A new point-of-care (POC) HIV virus load technology has been recently developed and designed to be utilized in decentralized settings. Alere Technologies GmbH*, Germany, developed the mPIMA HIV-1/2 VL plasma test which uses real time PCR technology with 50 μl and a turnaround time of one hour., Objective: Analyze the performance of mPIMA to detect and quantify HIV-1 and HIV-2 and compare with Abbott M2000 assay fooling patients HIV-1 failing ARV therapy., Study Design: In this study we evaluate the mPIMA HIV-1/2 VL plasma test using 413 specimens from 270 patients failing ARV therapy, and compared its performance with Abbott RealTime HIV-1 Viral Load assay on the m2000 system. In addition, were determined VL in plasma specimens obtained from HIV-2 infected patients., Results: The results strongly indicate that mPIMA HIV-1/2 VL plasma test can determine HIV-1 with concordance of 88.9 % (95 % CI 85.4-91.7) the reference test when 1000 HIV-1 VL threshold was used as WHO cutoff to identify therapy failure. The overall correlation between HIV-1 VL was 0928 (Pearson correlation coefficient of Linear regression) and the Bland-Altman showed a mean difference of -0.20 Log cp/mL between the two technology. mPIMA HIV-1/2 VL plasma test was also able to measure HIV-2 viral load in 16 specimens from Guinea-Bissau HIV-1/HIV-2 positive samples., Conclusions: These data support the use of mPIMA HIV-1/2 VL plasma test to follow up patients and select patients failing ART, guiding immediate clinical decisions such as adherence counseling or ART regimen switch during the patient consultation., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A new point-of-care HIV viral load, mPIMA HIV-1/2 VL, Abbott, USA, has been recently developed. This point-of-care viral load requires no skilled person to run and uses a small plasma volume (50μL). However, obtaining 50μL of plasma can be a challenge in limited resource settings. We validated a simple and easy method to obtain enough amount of plasma to run a point-of-care viral load. The study utilized 149 specimens from patients failing antiretroviral therapy. At least 250μL of whole blood was collected in a microtube/EDTA from fingerstick (fs-plasma) and immediately centrifuged. Parallel collection of venous blood to obtain plasma (vp-plasma) was used to compare performance in a point-of-care viral load assay and in methodology used in centralized laboratories Abbott M2000, Abbott, USA. The procedure for plasma collection takes less than 10min and in 94% of the cases only one fingerstick was sufficient to collect at least 250μL of blood. The Pearson correlation coefficient value for vp-plasma versus fs-plasma ran on mPIMA was 0.990. The Bland-Altman mean difference (md) for this comparison were virtually zero (md=-0.001) with limits of agreement between -0.225 and 0.223. In addition, the Pearson correlation coefficient value for fs-plasma in mPIMA versus vp-plasma in Abbott M2000 was 0.948 for values above the mPIMA limit of quantification (LoQ; from 800 to 1,000,000copies/mL). These results validate this simple plasma isolation method capable to be implemented in low resource countries where point-of-care decentralization is deeply needed., (Copyright © 2019 Sociedade Brasileira de Infectologia. Published by Elsevier España, S.L.U. All rights reserved.)

Importance: Recent studies have reported an increase in the number of fetuses and neonates with microcephaly whose mothers were infected with the Zika virus (ZIKV) during pregnancy. To our knowledge, most reports to date have focused on select aspects of the maternal or fetal infection and fetal effects., Objective: To describe the prenatal evolution and perinatal outcomes of 11 neonates who had developmental abnormalities and neurological damage associated with ZIKV infection in Brazil., Design, Setting, and Participants: We observed 11 infants with congenital ZIKV infection from gestation to 6 months in the state of Paraíba, Brazil. Ten of 11 women included in this study presented with symptoms of ZIKV infection during the first half of pregnancy, and all 11 had laboratory evidence of the infection in several tissues by serology or polymerase chain reaction. Brain damage was confirmed through intrauterine ultrasonography and was complemented by magnetic resonance imaging. Histopathological analysis was performed on the placenta and brain tissue from infants who died. The ZIKV genome was investigated in several tissues and sequenced for further phylogenetic analysis., Main Outcomes and Measures: Description of the major lesions caused by ZIKV congenital infection., Results: Of the 11 infants, 7 (63.6%) were female, and the median (SD) maternal age at delivery was 25 (6) years. Three of 11 neonates died, giving a perinatal mortality rate of 27.3%. The median (SD) cephalic perimeter at birth was 31 (3) cm, a value lower than the limit to consider a microcephaly case. In all patients, neurological impairments were identified, including microcephaly, a reduction in cerebral volume, ventriculomegaly, cerebellar hypoplasia, lissencephaly with hydrocephalus, and fetal akinesia deformation sequence (ie, arthrogryposis). Results of limited testing for other causes of microcephaly, such as genetic disorders and viral and bacterial infections, were negative, and the ZIKV genome was found in both maternal and neonatal tissues (eg, amniotic fluid, cord blood, placenta, and brain). Phylogenetic analyses showed an intrahost virus variation with some polymorphisms in envelope genes associated with different tissues., Conclusions and Relevance: Combined findings from clinical, laboratory, imaging, and pathological examinations provided a more complete picture of the severe damage and developmental abnormalities caused by ZIKV infection than has been previously reported. The term congenital Zika syndrome is preferable to refer to these cases, as microcephaly is just one of the clinical signs of this congenital malformation disorder.

There is a great variety of HIV-1 subtypes circulating in Brazil, including subtype C, whose prevalence is on the rise, particularly in the southern region. Many host and viral genetic factors may be involved in this trend. We evaluated the influence of human leukocyte antigen (HLA) class I alleles and killer-cell immunoglobulin-like receptor (KIR) genotypes on viral set point and T-CD4(+) parameters in 84 treatment-naïve HIV-1-positive individuals. Frequency data in the infected group were compared to data of 548 healthy control subjects. Individuals with the KIR AA genotype had a higher viral load (VL) than individuals with the KIR Bx genotype. The HIV-1 group was subdivided into three subgroups according to HLA-B allele presence: those with protection to disease alleles (HLA-B(+)), accelerated disease progression alleles (HLA-B(-)), or neither (HLA-B(o)) were grouped. We observed a significant effect of the HLA-B allele presence on VL. The HLA-B(+) group had significantly lower VL than the HLA-B(-) group and trended toward a lower VL than the HLA-B(o) group. There were significant differences between groups expressing extreme VL values: KIR-AA+HLA-B(-) vs. KIR Bx+HLA-B(+) and KIR-AA+HLA-B(o)vs. KIR Bx+HLA-B(+). The relationship of KIR/HLA host genetics with slow HIV disease progression in southern Brazil may be useful for vaccine developers, epidemiologists, and clinicians., (Copyright © 2016 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

Background and Rationale: Epidemics of hepatitis B and C are a public health burden, and their prevalence in Brazil varies among regions. We determined the prevalence of hepatitis markers in an urban university population in order to support the development of a comprehensive program for HBV immunization and HBV/HCV diagnosis. Students, employees, and visitors (n = 2,936, 31 years IQR 24.5-50, female = 69.0% and 81.1% with at least 12 years of education) were enrolled from May to November 2013. Antibodies against hepatitis B surface antigen (anti-HBs), against hepatitis B core antigen (anti-HBc), and hepatitis B surface antigen (HBsAg) were detected with enzyme immunoassays and anti-hepatitis C virus (anti-HCV) antibodies with a chemiluminescence immunoassay. The results were confirmed with polymerase chain reaction for HCV and nucleic acid amplification test for hepatitis B virus (HBV)., Results: The overall prevalence of markers among the participants was 0.136% (95% confidence interval [CI]: 0.003-0.270) for HBsAg, 6.44% (95% CI: 5.55-7.33%) for anti-HBc, 50.8% (95% CI: 48.9-52.7%) for anti-HBs > 10 mIU/mL, and 0.44% (95% CI: 0.20-0.68) for anti-HCV. Almost 30.4% had anti-HBs titers > 100 mIU/mL. Participants with a detectable HCV viral load (n = 9) were infected with genotype 1a., Conclusions: In an urban university population, in which 80% of participants had > 11 years of education, prevalence increased with age, and self-declared ethnicity for anti-HBc and with age, marital status and professional activity for anti-HCV antibodies. A periodical offer of HCV rapid testing should be implemented, and HBsAg rapid testing should be offered to individuals above 20 years of age.

Introduction: Prevention of acute HIV infections in pregnancy is required to achieve elimination of pediatric HIV. Identification and support for HIV negative pregnant women and their partners, particularly serodiscordant couples, are critical. A mixed method study done in Southern Mozambique estimated HIV incidence during pregnancy, associated risk factors and factors influencing partner's HIV testing., Methods: Between April 2008 and November 2011, a prospective cohort of 1230 HIV negative pregnant women was followed during pregnancy. A structured questionnaire, HIV testing, and collection of dried blood spots were done at 2-3 scheduled visits. HIV incidence rates were calculated by repeat HIV testing and risk factors assessed by Poisson regression. A qualitative study including 37 individual interviews with men, women, and nurses and 11 focus group discussions (n = 94) with men, women and grandmothers explored motivators and barriers to uptake of male HIV testing., Results: HIV incidence rate was estimated at 4.28/100 women-years (95%CI: 2.33-7.16). Significant risk factors for HIV acquisition were early sexual debut (RR 3.79, 95%CI: 1.04-13.78, p = 0.04) and living in Maputo Province (RR 4.35, 95%CI: 0.97-19.45, p = 0.05). Nineteen percent of women reported that their partner had tested for HIV (93% knew the result with 8/213 indicating an HIV positive partner), 56% said their partner had not tested and 19% did not know their partner test status. Of the 14 seroconversions, only one reported being in a serodiscordant relationship. Fear of discrimination or stigma was reported as a key barrier to male HIV testing, while knowing the importance of getting tested and receiving care was the main motivator., Conclusions: HIV incidence during pregnancy is high in Southern Mozambique, but knowledge of partners' HIV status remains low. Knowledge of both partners' HIV status is critical for maximal effectiveness of prevention and treatment services to reach elimination of pediatric HIV/AIDS.

The HIV/AIDS pandemic is primarily caused by HIV-1. Another virus type, HIV-2, is found mainly in West African countries. We hypothesized that population migration and mobility in Africa may have facilitated the introduction and spreading of HIV-2 in Mozambique. The presence of HIV-2 has important implications for diagnosis and choice of treatment of HIV infection. Hence, the aim of this study was to estimate the prevalence of HIV-2 infection and its genotype in Maputo, Mozambique.HIV-infected individuals (N = 1,200) were consecutively enrolled and screened for IgG antibodies against HIV-1 gp41 and HIV-2 gp36 using peptide-based enzyme immunoassays (pepEIA). Specimens showing reactivity on the HIV-2 pepEIA were further tested using the INNO-LIA immunoblot assay and HIV-2 PCR targeting RT and PR genes. Subtype analysis of HIV-2 was based on the protease gene.After screening with HIV-2 pepEIA 1,168 were non-reactive and 32 were reactive to HIV-2 gp36 peptide. Of this total, 30 specimens were simultaneously reactive to gp41 and gp36 pepEIA while two samples reacted solely to gp36 peptide. Only three specimens containing antibodies against gp36 and gp105 on the INNO-LIA immunoblot assay were found to be positive by PCR to HIV-2 subtype A.The proportion of HIV-2 in Maputo City was 0.25% (90%CI 0.01-0.49). The HIV epidemic in Southern Mozambique is driven by HIV-1, with HIV-2 also circulating at a marginal rate. Surveillance program need to improve HIV-2 diagnosis and consider periodical survey aiming to monitor HIV-2 prevalence in the country.

Human leukocyte antigen (HLA) has been used for several decades as genetic markers for analyzing diversity of gene pool origin, platelet transfusion, tissue transplantation, disease susceptibility or resistance, and forensic and anthropological studies. In the present study, the allele and haplotype frequencies of HLA-A, -B, and -DRB1 were studied in 250 unrelated Mozambican individuals (black African from south of Mozambique Basin) by using a low-medium resolution polymerase chain reaction-Luminex typing method. A total of 18 A, 25 B, and 13 DRB1 alleles were identified. The most frequent HLA-A, -B, and -DRB1 alleles were HLA-A*30 (23.9%), HLA-B*15 (15.6%), and HLA-DRB1*13 (19.8%), respectively. The most frequent two-locus haplotypes were HLA-A*30-B*42 (7.4%) and HLA-B*42-DRB1*03 (5.4%), and three-locus haplotypes were HLA-A*30-B*42-DRB1*03 (4.9%), and HLA-A*02-B*58-DRB1*11 (4.1%). Allele distribution and haplotype analysis demonstrated that Mozambican population shares HLA patterns with sub-Saharan populations., (2010 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

Background: Screening for human T-lymphotropic virus-1/2 (HTLV-1/2) infection is not performed in blood banks in Mozambique. The aim was to determine the prevalence of HTLV-1/2 among blood donors of the Maputo Central Hospital Blood Bank and measure the coinfection rate of HTLV-1/2 with human immunodeficiency virus (HIV), hepatitis B virus (HBV), and syphilis., Study Design and Methods: A total of 2019 consecutive blood donors were screened for HTLV-1/2 antibodies, HIV-1/2 antibodies, hepatitis B surface antigen (HBsAg), and rapid plasma reagin (RPR) for syphilis. Specimens reactive on a first HTLV-1/2 enzyme immunoassay (EIA) were retested using a second EIA. Specimens that were dually reactive on both EIAs were further tested using Western blot (WB) and real-time polymerase chain reaction (PCR)., Results: All 18 dually reactive specimens (0.89%; 95% confidence interval, 0.48%-1.30%) were positive for the presence of HTLV-1 by WB and real-time PCR. HTLV-2 was not detected. The prevalences of anti-HIV, HBsAg, and reactivity in the RPR test were 5.72, 6.01, and 0.98 percent, respectively. There was no significant association between HTLV-1 infection and demographic variables (age and sex) or serologic markers (HIV, HBsAg, and RPR). For the 17 HTLV-1-positive donors for whom serologic data for HIV, HBsAg, and syphilis RPR were available, 2 showed coinfection with HIV and 1 with HBV., Conclusion: Compared to other infectious agents, HTLV-1 is present at relatively low levels among blood donors in Mozambique. Cost and logistics will present as major challenges for introducing HTLV-1/2 screening in blood banks. In blood banks in Southern Africa where EIA testing is possible, a sequential algorithm of two EIAs may be a cost-efficient option for HTLV-1/2 screening.

BACKGROUND: Serological tests to detect antibodies specific to Plasmodium vivax could be a valuable tool for epidemiological studies, for screening blood donors in areas where the malaria is not endemic and for diagnosis of infected individuals. Because P. vivax cannot be easily obtained in vitro, ELISA assays using total or semi-purified antigens are rarely used. Based on this limitation, we tested whether recombinant proteins representing the 19 kDa C-terminal region of the merozoite surface protein-1 of P. vivax (MSP119) could be useful for serological detection of malaria infection. METHODS: Three purified recombinant proteins produced in Escherichia coli (GST-MSP119, His6-MSP119 and His6-MSP119-PADRE) and one in Pichia pastoris (yMSP119-PADRE) were compared for their ability to bind to IgG antibodies of individuals with patent P. vivax infection. The method was tested with 200 serum samples collected from individuals living in the north of Brazil in areas endemic for malaria, 53 serum samples from individuals exposed to Plasmodium falciparum infection and 177 serum samples from individuals never exposed to malaria. RESULTS: Overall, the sensitivity of the ELISA assessed with sera from naturally infected individuals was 95%. The proportion of serum samples that reacted with recombinant proteins GST-MSP119, His6-MSP119, His6-MSP119-PADRE and yMSP119-PADRE was 90%, 93.5%, 93.5% and 93.5%, respectively. The specificity values of the ELISA determined with sera from healthy individuals and from individuals with other infectious diseases were 98.3% (GST-MSP119), 97.7% (His6-MSP119 and His6-MSP119-PADRE) or 100% (yMSP119-PADRE). CONCLUSIONS: Our study demonstrated that for the Brazilian population, an ELISA using a recombinant protein of the MSP119 can be used as the basis for the development of a valuable serological assay for the detection of P. vivax malaria.

Context: The hemoglobin (Hb) level is the most-used parameter for screening blood donors for the presence of anemia, one of the most-used methods for measuring Hb levels is based on photometric detection of cyanmetahemoglobin, as an alternative to this technology, HemoCue has developed a photometric method based on the determination of azide metahemoglobin., Objective: To evaluate the performance of three methods for hemoglobin (Hb) determination in a blood bank setting., Design: Prospective study utilizing blood samples to compare methods for Hb determination., Setting: Hemotherapy Service of the Hospital Israelita Albert Einstein, a private institution in the tertiary health care system., Sample: Serial blood samples were collected from 259 individuals during the period from March to June 1996., Main Measurements: Test performances and their comparisons were assessed by the analysis of coefficients of variation (CV), linear regression and mean differences., Results: The CV for the three methods were: Coulter 0.68%, Cobas 0.82% and HemoCue 0.69%. There was no difference between the mean Hb determination for the three methods (p>0.05). The Coulter and Cobas methods showed the best agreement and the HemoCue method gave a lower Hb determination when compared to both the Coulter and Cobas methods. However, pairs of methods involving the HemoCue seem to have narrower limits of agreement (+/- 0.78 and +/- 1.02) than the Coulter and Cobas combination (+/- 1.13)., Conclusion: The three methods provide good agreement for hemoglobin determination.

The genetic variation of the human immunodeficiency virus type 1 (HIV-1) protease gene (prt) permits the classification of HIV-1 strains into five distinct protease subtypes, which follow the gag subtyping patterns. The susceptibilities of non-B-subtype strains to protease inhibitors (PIs) and other antiretroviral drugs remain largely unknown. Subtype F is the main non-B strain contributing to the Brazilian epidemic, accounting for 15 to 20% of these infections. In this work, we report the findings on 81 isolates from PI-naive Brazilian patients collected between 1993 and 1997. In addition, the relevant PI resistance mutations and their phenotypes were determined in vitro for 15 of these patients (B = 9 and F = 6). Among these, the subtype F samples evidenced high sensitivities in vitro to ritonavir and indinavir, with MICs at which 50 and 90% of the isolates are inhibited similar to those of both the Brazilian and the U.S. subtype B isolates. Analysis of the 81 Brazilian prt sequences demonstrated that the subtype F consensus sequence differs from the U.S. and Brazilian subtype B consensus in eight positions (I15V, E35D, M36I, R41K, R57K, Q61N, L63P, and L89M). The frequency of critical PI resistance substitutions (amino acid changes D30N, V82A/F/T, I84V, N88D, and L90M) among Brazilian isolates is very low (mean, 2.5%), and the associated secondary substitutions (amino acid positions 10L, 20K, 36M, 46M, 48G, 54I, 63P, 71A, and 77A) are infrequent. These observations document the relative rarity of resistance to PIs in the treatment of patients infected with HIV-1 subtype F in South America.

The human T-cell lymphotropic viruses type I and type II are closely related human retroviruses that have similar biological properties, genetic organization and tropism for T lymphocytes. Along with the simian T-cell lymphoma virus type I, they define the group of retroviruses known as the primate T-cell leukemia/lymphoma viruses. Initially identified in 1980, the human T-cell lymphotropic virus type I has been implicated as the etiologic agent of adult T-cell leukemia/lymphoma and of a degenerative neurologic disorder known as tropical spastic paraparesis or human T-cell lymphotropic virus type I-associated myelopathy. The intriguing link between human T-cell lymphotropic virus type, T-cell malignancy, and a totally unrelated and non-overlapping neurological disorder suggests divergent and unique pathogenetic mechanisms. This review will address the epidemiology, molecular biology, and pathogenesis of human T-cell leukemia viruses.

Objective: To determine the relative prevalence of HIV-1 and HIV-2 and to evaluate the World Health Organization testing strategy for HIV diagnosis in a low-risk population in Brazil. In addition, to assess risk factors for HIV infection., Design: Sera obtained from 9885 consecutive blood donors were screened in parallel by two HIV enzyme-linked immunosorbent assays (ELISA) with different antigen composition and test principles (Ortho HIV-1 and Wellcozyme HIV-1/2). Samples reactive to either ELISA were submitted to a Western blot assay and to a rapid HIV-1/2 ELISA (Sero-Immuno Diagnostics). An ELISA test with specific HIV-1/HIV-2-derived synthetic peptide was used to discriminate between samples reactive on the Wellcozyme HIV-1/2 assay. Demographic and serological data were used to address risk factors for HIV infection., Results: All the 28 Western blot-confirmed positive samples were reactive in both Ortho HIV-1 and Wellcozyme HIV-1/2 assays (sensitivity, 100%). The Wellcozyme HIV-1/2 specificity (99.9%) was higher than Ortho HIV-1 (99.5%). If sample reactivity to both tests was considered positive, the sensitivity and specificity of the screening would be 100%. However, further analysis with a third rapid HIV-1/2 ELISA reduced both the sensitivity and the specificity of the sequential testing strategy. Discrimination between HIV-1 and HIV-2 showed evidence for the presence of HIV-1 only. Finally, in the group aged 18-35 years, the presence of serological markers of hepatitis C virus and hepatitis B virus infections and the elevated levels of beta 2-microglobulin were variables associated with the identification of HIV-1-seropositive blood donors., Conclusion: In a low-risk population, application of two high quality ELISA tests with different antigens and test principles can replace the use of the Western blot. In addition to the cost being reduced by 10-16%, a rapid diagnosis and the absence of indeterminate Western blot results confer an advantage to this strategy.

We compared the performance of a rapid and simple anti-CD4 antibody-coated microsphere assay with flow cytometry and immunofluorescence for quantitation of absolute count of CD4+ T lymphocytes. A longitudinal evaluation of CD4+ T lymphocytes by flow cytometry and microsphere assay in 10 human immunodeficiency virus (HIV)-seronegative and 59 HIV-seropositive individuals was conducted over a period of 9 months. Standard flow cytometry analysis was performed to establish the absolute CD4+ T-lymphocyte count. The microsphere assay uses whole blood; CD14+ and CD4+ cells are first blocked by small latex beads coated with anti-CD14 antibody, and remaining cells are stained with larger anti-CD4 antibody-coated beads. Cells rosetted with only anti-CD4 antibody-coated beads are counted with use of a hemacytometer. Immunofluorescence microscopy was performed by standard techniques with use of peripheral blood mononuclear cells. The predictive value for stratification of HIV-seropositive patients by CD4+ T-lymphocyte values of < 200/microliters was 95% when the microsphere method was compared with flow cytometry. A correlation coefficient of 0.91 between the two assay methods was demonstrated in 281 CD4+ T-lymphocyte tests for absolute count. Finally, the flow cytometry method yielded better results than did the microsphere assay and immunofluorescence microscopy, in descending order of accuracy. The microsphere method should be effective in determining absolute CD4+ T-lymphocyte count in developing countries where, for a variety of reasons, no other method can be reliably performed.

Mycobacterium avium complex (MAC) infection has not been reported as a major opportunistic infection among patients with AIDS in Latin America or Africa. In this study, 125 AIDS patients who had persistent fever, anemia, and leukopenia were examined among 2628 AIDS patients admitted to Instituto de Infectologia Emilio Ribas between May 1990 and April 1992. From the bone marrow aspirates of the 125 patients, MAC was isolated from 23 (18.4%) and Mycobacterium tuberculosis was isolated from 9 (7.2%). Between 1985 and 1990, only 11 MAC isolations among 60,000 cultures obtained from human immunodeficiency virus-seronegative patients were documented in São Paulo. Hence, the minimal estimated rate of MAC infection in AIDS patients in this city was 23/2628, or 0.88%. These findings suggest that MAC infection is an important opportunistic infection, especially among a subset of patients with AIDS in Brazil who have clinical characteristics and risk activities similar to those associated with MAC infections in North America and Europe.

Monocyte interaction with fibronectin (Fn) involves specific cell surface receptors and results in cell attachment and differentiation. We have studied the regulation of these receptors using the promonocytic cell line U937 and its PMA-induced differentiation as a model. We recently reported that U937 cells interact with two sites in Fn, RGD and CS-1, via two independent receptors (O. C. Ferreira, A. Garcia-Pardo, and C. Bianco (1990) J. Exp. Med. 171, 351). In this study we have determined the effects of PMA on the interaction of U937 cells with both sites in Fn. PMA-U937 cells showed an enhanced attachment to Fn and to an RGD-containing 80-kDa Fn fragment. This enhancement paralleled a two- to threefold increase in the surface expression of the RGD-dependent receptor alpha 5 beta 1. An anti-alpha 5 beta 1 mAb completely inhibited cell adhesion to Fn and to the 80-kDa fragment. alpha 5 beta 1 receptors from untreated and PMA-treated U937 cells were isolated on 80-kDa-Sepharose columns and shown to contain a similar complex of 152/125-kDa proteins, although proteins from PMA-treated cells had slightly faster mobility on SDS-gels. In contrast, the total number of PMA-U937 cells adhering to a 38-kDa Fn fragment (containing the CS-1 site) was lower when compared to that of untreated cells. This decrease was accompanied by a 50% loss of cell surface alpha 4 beta 1, the specific receptor for CS-1. Our results indicate that differentiation of U937 cells enhances adhesion to Fn primarily by up-regulating the alpha 5 beta 1 Fn receptor. PMA also induces a down-regulation of alpha 4 beta 1, suggesting that these two integrins play different roles during monocyte differentiation.

In this report we have studied the mechanism of human B lymphocyte adhesion to fibronectin and to proteolytic fragments of this protein. B cells adhered to fibronectin and to a 38-kDa fragment, derived from the A chain, containing the Hep II domain and most of the type III connecting segment, IIICS, of fibronectin. Cells did not bind to an 80-kDa fragment containing the RGD adhesive sequence of fibronectin. Attachment to fibronectin or to the 38-kDa fragment was not affected by the 80-kDa fragment, the GRGDSPC synthetic peptide, or by a mAb specific for the alpha chain of the RGD-dependent fibronectin receptor, alpha 5 beta 1. However, B cell adhesion to fibronectin was inhibited by the synthetic peptides CS-1, comprising the first 25 amino acids of IIICS and B12, containing the sequence LHGPEILDVPST of CS-1 (residues 14-25). Moreover, this sequence was shown to be sufficient to induce stable cell adhesion when coated on plastic surfaces. A mAb specific for the alpha-subunit of the alpha 4 beta 1 integrin, completely inhibited B cell attachment to B12, CS-1, 38 kDa, and fibronectin coated substrata. These data clearly indicate that adhesion of B lymphocytes to fibronectin is exclusively mediated by the interaction of alpha 4 beta 1 with residues 14-25 of the IIICS region in fibronectin. Therefore this interaction constitutes an alternative pathway of adhesion to fibronectin, independent of RGD and alpha 5 beta 1.

U937 cells attach to the RGDS-containing 80-kD fragment of fibronectin (Fn). The present report examined whether these cells recognize other domains of Fn. U937 cells attach to a 38-kD fragment derived from the A chain of Fn, which includes the Hep II domain and most of the alternatively spliced IIICS region. U937 did not bind to a 58-kD fragment derived from the B chain (which lacks IIICS) and has the Hep II site. They also did not bind to a 31-kD COOH-terminal fibrin-binding fragment or to a 29-kD fragment containing the Hep I domain. Cell adhesion to the 38-kD fragment was not inhibited by the 80-kD fragment, by GRGDSPC synthetic peptides, or by a mAb directed to the RGDS-containing domain of Fn. Attachment was completely inhibited by the 38-kD fragment and by the synthetic peptide CS-1, comprising the first 25 amino acid residues of IIICS. These results indicate that U937 cells interact with two sites of Fn, the RGDS-containing region, and the IIICS region.

Activated monocytes acquire the ability to induce clot formation in platelet-poor citrated human plasma. The generation of this procoagulant activity (PCA) is dependent upon an interactive pathway between monocytes and T lymphocytes. Here we show that an ongoing autologous mixed lymphocyte reaction (AMLR) can elicit a T-cell-instructed PCA. PCA was measured by the ability of the cells to accelerate the clotting time of pooled citrated platelet-poor human plasma. AMLR was measured by tritiated thymidine incorporation. PCA and AMLR had very similar kinetics. Correlation coefficients between both reactions ranged from 0.59 to 0.99. Addition of an anti-DR monoclonal antibody blocked both reactions. T-Lymphocyte-depleted cell populations did not increase their level of PCA after 6 days in culture. Addition of autologous T cells to the T-depleted population restored its ability to produce PCA. Cyclosporin A blocked the peripheral blood mononuclear cell ability to generate PCA. A lymphokine generated during the AMLR was able to induce PCA in normal mononuclear cells. The results indicate that self recognition activates monocytes to produce PCA and suggests that this mechanism may represent a link between immunoregulatory phenomena and blood coagulation.

1. The ability of peripheral blood mononuclear cells (PBMC) from Chagas' disease patients to induce monocyte procoagulant activity (PCA) in response to concanavalin A (Con A) and to a Con A induced lymphokine was studied. 2. In spite of the variability of PCA levels among both chagasic patients and normal controls, statistical analysis of the data permitted us to draw the following general conclusions. 3. The Con A-induced monocyte PCA measured in 17 assays of 15 chagasic patients was significantly lower than the PCA response of 18 normal controls or of 11 patients with non-chagasic myocardiopathies. 4. The response of PBMC from chagasic patients to lymphokine was also lower than that observed for normal controls. 5. These results suggest that monocytes from chagasic patients are deficient for the generation of PCA which is an in vitro correlate of the delayed-type hypersensitivity reaction.