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1.
JHEP Rep ; 4(10): 100533, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36052221

ABSTRACT

Background & Aims: Strategies to implement HBV screening and treatment are critical to achieve HBV elimination but have been inadequately evaluated in sub-Saharan Africa (sSA). Methods: We assessed the feasibility of screen-and-treat interventions in 3 real-world settings (community, workplace, and hospital) in Senegal. Adult participants were screened using a rapid HBsAg point-of-care test. The proportion linked to care, the proportion who had complete clinical staging (alanine transaminase [ALT], viral load, and FibroScan®), and the proportion eligible for treatment were compared among the 3 intervention groups. Results: In 2013-2016, a total of 3,665 individuals were screened for HBsAg in the community (n = 2,153) and in workplaces (n = 1,512); 199/2,153 (9.2%) and 167/1,512 (11%) were HBsAg-positive in the community and workplaces, respectively. In the hospital setting (outpatient clinics), 638 HBsAg-positive participants were enrolled in the study. All infected participants were treatment naïve. Linkage to care was similar among community-based (69.9%), workplace-based (69.5%), and hospital-based interventions (72.6%, p = 0.617). Of HBV-infected participants successfully linked to care, full clinical staging was obtained in 47.5% (66/139), 59.5% (69/116), and 71.1% (329/463) from the community, workplaces, and hospitals, respectively (p <0.001). The proportion eligible for treatment (EASL criteria) differed among community- (9.1%), workplace- (30.4%), and hospital-based settings (17.6%, p = 0.007). Acceptability of antiviral therapy, adherence, and safety at 1 year were very good. Conclusions: HBV screen-and-treat interventions are feasible in non-hospital and hospital settings in Senegal. However, the continuum of care is suboptimal owing to limited access to full clinical staging. Improvement in access to diagnostic services is urgently needed in sSA. Lay summary: Hepatitis B infection is highly endemic in Senegal. Screening for infection can be done outside hospitals, in communities or workplaces. However, the hepatitis B continuum of care is suboptimal in Senegal and needs to be simplified to scale-up diagnosis and treatment coverage.

2.
Pan Afr Med J ; 38: 294, 2021.
Article in English | MEDLINE | ID: mdl-34178213

ABSTRACT

INTRODUCTION: quantification of hepatitis B virus DNA, a key element in the management of chronic hepatitis B, allows a more direct and reliable measurement of viral replication and monitoring of the virological response to therapy. Polymerase chain reaction (PCR) platforms performing this quantification and adaptable to intermediate laboratories have been developed. Thus, this study was conducted to evaluate the on-site performance of the AMPLIX® hepatitis B virus (HBV) real-time PCR technique in comparison with the COBAS AmpliPrep™ technique. METHODS: performance of the AMPLIX® HBV real-time PCR technique was evaluated with repeatability and intermediate precision (reproducibility) determined. The comparison with COBAS Taqman was performed by testing, in parallel, 42 plasma samples. The statistical analysis using Meth Val® software was focused on correlation and concordance determination. RESULTS: AMPLIX® real-time PCR assay showed good reproducibility for the low (CV=6.65%) and high (CV=3.15%) control levels but also good repeatability for both the low (CV=2.12%) and high (CV=1.60%) concentration levels. Accuracy obtained in our study were less than acceptability limit fixed to 5%. Viral load measurements between Amplix and COBAS Taqman correlated strongly with a correlation coefficient of 0.97%. Concordance analysis gave an average of the differences of 0.54 log IU/L between the viral load measurements of the 2 techniques. CONCLUSION: based on these results, the Amplix real-time PCR platform for the quantification of HBV DNA can be considered as a reliable system for the monitoring of chronic hepatitis B and also a system adapted to intermediate laboratories.


Subject(s)
Hepatitis B virus/isolation & purification , Hepatitis B, Chronic/diagnosis , Nucleic Acid Amplification Techniques/methods , DNA, Viral/blood , Hepatitis B virus/genetics , Hepatitis B, Chronic/virology , Humans , Real-Time Polymerase Chain Reaction , Reproducibility of Results , Senegal , Viral Load
3.
J Viral Hepat ; 28(7): 1003-1010, 2021 07.
Article in English | MEDLINE | ID: mdl-33749097

ABSTRACT

The clinical utility of quantifying hepatitis B surface antigen (qHBsAg) levels in African subjects with chronic hepatitis B virus (HBV) infection has been poorly documented. From a multicentre cohort of 944 HBV-infected African patients, we aimed to assess whether qHBsAg alone can accurately identify i) those in a HBeAg-negative chronic HBV infection phase at low risk of liver disease progression and ii) those in need of antiviral therapy according to the 2017 EASL guidelines. We analysed 770 HBV mono-infected treatment-naïve patients, mainly males (61%) from West Africa (92%), median age 35 years (IQR: 30-44), median HBV DNA: 95.6 IU/ml (10.0-1,300.0), median qHBsAg 5,498 IU/ml (1,171-13,000) and HBeAg-pos 38 (5%). A total of 464/770 (60.2%) patients were classified as HBeAg-negative chronic infection (median age 36 years (31-46), median ALT 23 IU/l (18-28), median HBV-DNA 33.5 IU/ml (3.8-154.1), median LSM 4.8 kPa (4.1-5.8)) and qHBsAg levels had poor accuracy to identify these subjects with an AUROC at 0.58 (95%CI: 0.54-0.62), sensitivity 55.0% and specificity 55.6%; 118/770 (15.3%) patients were eligible for treatment according to the 2017 EASL criteria. qHBsAg correlated poorly with HBV DNA and had poor accuracy to select patients for antiviral therapy with an AUROC at 0.54 (0.49-0.60), sensitivity 46.6% and specificity 46.9%. In African treatment-naïve HBV-infected subjects, the clinical utility of qHBsAg to identify subjects in HBeAg-negative infection phase or subjects eligible for antiviral therapy seems futile. Whether qHBsAg levels can be used as a predictor of long-term liver complications in Africa needs to be further investigated.


Subject(s)
Hepatitis B, Chronic , Hepatitis B , Adult , DNA, Viral , Hepatitis B Surface Antigens , Hepatitis B e Antigens , Hepatitis B virus/genetics , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/drug therapy , Humans , Male
4.
Med Sci (Paris) ; 35(5): 431-439, 2019 May.
Article in French | MEDLINE | ID: mdl-31115326

ABSTRACT

Despite the existence of an effective vaccine, HBV infects 257 million people worldwide and is the cause of the majority of HCC. With an annual mortality rate of 887 000 patients in 2015, this cancer is the second deadliest. Low-income countries such as ones in sub-Saharan Africa are the most at risk due to the limited access to healthcare. To overcome this and born from an international research collaboration within an EU project, the Prolifica study aimed at evaluating a screen-and-treat program to prevent HBV complications, and more particularly HCC. Based on communities, facilities and hospitals HBsAg+ detection, the study lasted from 2011 to 2016. From the "cost effectiveness" feasibility of such a program to the development of simple scores for antiviral treatment, Prolifica uncovered data of crucial importance in a region with low HBV infection awareness, transmissions modes and prevention means which could have impacts on public health policies.


Subject(s)
Hepatitis B/complications , Liver Cirrhosis/prevention & control , Liver Cirrhosis/virology , Liver Neoplasms/prevention & control , Liver Neoplasms/virology , Africa South of the Sahara , Health Policy , Health Services Accessibility/statistics & numerical data , Hepatitis B/diagnosis , Hepatitis B/prevention & control , Hepatitis B Surface Antigens/blood , Humans , Poverty
5.
PLoS One ; 12(6): e0179025, 2017.
Article in English | MEDLINE | ID: mdl-28614401

ABSTRACT

BACKGROUND: Compliance with WHO guidelines on HBV screening and treatment in HIV-coinfected patients is often challenging in resource limited countries and has been poorly assessed in sub-Saharan Africa. METHODS: Between 2015 and 2016, we assessed physician's compliance with WHO guidelines on HIV-HBV coinfection in the largest HIV clinic in The Gambia, and the hepatic outcomes in HIV-HBV coinfected patients as compared to randomly selected HIV-monoinfected controls. RESULTS: 870 HIV-infected patients regularly seen in this clinic agreed to participate in our study. Only 187 (21.5%, 95% CI 18.8-24.3) had previously been screened for HBsAg, 23 (12.3%, 95% CI 8.0-17.9) were positive of whom none had liver assessment and only 6 (26.1%) had received Tenofovir. Our HBV testing intervention was accepted by all participants and found 94/870 (10.8%, 95% CI 8.8-13.1) positive, 78 of whom underwent full liver assessment along with 40 HBsAg-negative controls. At the time of liver assessment, 61/78 (78.2%) HIV-HBV coinfected patients received ART with 7 (11.5%) on Tenofovir and 54 (88.5%) on Lamivudine alone. HIV-HBV coinfected patients had higher APRI score compared to controls (0.58 vs 0.42, p = 0.002). HBV DNA was detectable in 52/53 (98.1%) coinfected patients with 14/53 (26.4%) having HBV DNA >20,000 IU/L. 10/12 (83.3%) had at least one detectable 3TC-associated HBV resistance, which tended to be associated with increase in liver fibrosis after adjusting for age and sex (p = 0.05). CONCLUSIONS: Compliance with HBV testing and treatment guidelines is poor in this Gambian HIV programme putting coinfected patients at risk of liver complications. However, the excellent uptake of HBV screening and linkage to care in our study suggests feasible improvements.


Subject(s)
Antiviral Agents/therapeutic use , HIV Infections/drug therapy , Hepatitis B/diagnosis , Lamivudine/therapeutic use , Tenofovir/therapeutic use , Adult , Antiretroviral Therapy, Highly Active , Coinfection/diagnosis , Cross-Sectional Studies , Female , Gambia , Hepatitis B/drug therapy , Hepatitis B/epidemiology , Humans , Male , Mass Screening/statistics & numerical data , Middle Aged , Practice Guidelines as Topic , Treatment Outcome , Young Adult
6.
Lancet Glob Health ; 4(8): e559-67, 2016 08.
Article in English | MEDLINE | ID: mdl-27443781

ABSTRACT

BACKGROUND: Despite the introduction of immunisation for hepatitis B virus (HBV) in the 1990s, HBV-related morbidity and mortality remain high in sub-Saharan Africa. Identification and treatment of asymptomatic people with chronic HBV infection should reduce the disease burden. We therefore assessed the feasibility of a screen-and-treat programme for HBV infection in The Gambia, west Africa, and estimated the proportion of HBV-infected people who had significant liver disease in need of treatment. METHODS: Between Dec 7, 2011, and Jan 24, 2014, individuals living in randomly selected communities in western Gambia were offered hepatitis B surface antigen (HBsAg) screening via a point-of-care test. The test was also offered to potential blood donors attending the central hospital in the capital, Banjul. HBsAg-positive individuals were invited for a comprehensive liver assessment and were offered treatment according to international guidelines. We defined linkage to care as visiting the liver clinic at least once. Eligibility for treatment was judged in accordance with the 2012 European Association for the Study of the Liver guidelines. FINDINGS: HBsAg screening was accepted by 5980 (weighted estimate 68·9%, 95% CI 65·0-72·4) of 8170 adults from 27 rural and 27 urban communities and 5559 (81·4%, 80·4-82·3) of 6832 blood donors. HBsAg was detected in 495 (8·8%, 7·9-9·7) individuals in communities and 721 (13·0%, 12·1-13·9) blood donors. Prevalence was higher in men (239 [10·5%, 8·9-12·1] of 2328 men vs 256 [7·6%, 6·5-8·7] of 3652 women; p=0·004) and middle-aged participants. Linkage to care was high in the communities, with 402 (81·3%) of 495 HBsAg-positive individuals attending the clinic. However, only 300 (41·6%) of 721 HBsAg-positive people screened at the blood bank linked into care. Of those who attended the clinic, 18 (4·4%, 2·5-7·7) patients from the communities and 29 (9·7%, 6·8-13·6) from the blood bank were eligible for treatment. Male sex was strongly associated with treatment eligibility (odds ratio 4·35, 1·50-12·58; p=0·007). INTERPRETATION: HBV infection remains highly prevalent in The Gambia. The high coverage of community-based screening, good linkage into care, and the small proportion of HBsAg carriers who need treatment suggest that large-scale screening and treatment programmes are feasible in sub-Saharan Africa. FUNDING: European Commission (FP7).


Subject(s)
Communicable Diseases , Hepatitis B/diagnosis , Mass Screening/methods , Point-of-Care Systems , Adult , Age Factors , Antiviral Agents , Blood Donors , Feasibility Studies , Female , Gambia/epidemiology , Hepatitis B/epidemiology , Hepatitis B Surface Antigens/blood , Hepatitis B virus/immunology , Humans , Liver Cirrhosis/diagnosis , Liver Cirrhosis/therapy , Male , Middle Aged , Prevalence , Sex Factors
7.
J Clin Microbiol ; 53(4): 1156-63, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25631805

ABSTRACT

Hepatitis B virus (HBV) infection is a leading cause of death in sub-Saharan Africa (SSA). Point-of-care tests for hepatitis B surface antigen (HBsAg) could be an ideal tool for a large-scale HBV screening/treatment program in SSA. Using data from the PROLIFICA (Prevention of Liver Fibrosis and Cancer in Africa) program, we conducted a cross-sectional study to assess the diagnostic accuracy of three point-of-care tests (Determine, Vikia, and Espline) for the detection of HBsAg in the field or a laboratory setting in the Gambia. In the field, we used finger-prick whole blood for the Determine and Vikia tests and dried blood spots for the reference standard test (AxSYM HBsAg enzyme-linked immunosorbent assay [ELISA]). In the laboratory we used serum for the Determine, Espline, and reference test (Architect chemiluminescent microparticle immunoassay). Of 773 participants recruited at the community and 227 known chronic HBV carriers (1,000 subjects in total), 293 were positive for HBsAg. The sensitivity and specificity of the Determine test were 88.5% and 100% in the field and 95.3% and 93.3% in the laboratory setting, respectively. The sensitivity and specificity were 90.0% and 99.8% for the Vikia test (in the field) and 93.9% and 94.7% for the Espline test (in the laboratory). There was no evidence that one kit was better than another. Most of the patients with false-negative results (18/19) were classified as inactive chronic carriers. In summary, the three point-of-care tests had acceptable ranges of diagnostic accuracy. These tests may represent accurate, rapid, and inexpensive alternatives to serology testing for the screening of HBV infection at field level in SSA.


Subject(s)
Hepatitis B Surface Antigens/blood , Hepatitis B/diagnosis , Point-of-Care Systems , Adolescent , Adult , Aged , Aged, 80 and over , Enzyme-Linked Immunosorbent Assay/methods , Female , Gambia , Humans , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity , Young Adult
8.
J Virol Methods ; 188(1-2): 97-103, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23266258

ABSTRACT

The objective of this study was to investigate the performance of the ViroSeq HIV-1 Genotyping System v2.0 on HIV-1 non-B strains identified in Senegalese patients. The study involved 150 patients, and genotyping was performed using the ViroSeq HIV-1 Genotyping System v2.0 or an in-house method developed by the French National Agency on AIDS Research AC11 when the ViroSeq HIV-1 Genotyping System v2.0 failed. The sequences were edited to assess the performance of sequencing primers at their presumed binding regions. The Polymorphism was studied in the regions between the sequences of Senegalese patients and the subtype B strains used as references. The phylogenetic analysis showed a predominance of CRF02_AG (88/150; 58.7%) and the circulation of 11 subtypes/CRFs, 16 unique recombinant forms (URFs) and one unclassified sample. The amplification and sequencing rates were 98% (147/150) and 96.6% (142/147), respectively. This study showed that only primer B exhibited 100% success, while the failure rate ranged from 1.4% to 71.4% for the other primers (D: 71.4%, A and H: 12.2%, F: 7.5%, G: 5.5% and C: 1.4%). These findings suggest the need for an alternative method or alternative primers for non-B strains that were not sequenced successfully using the ViroSeq HIV-1 Genotyping System v2.0.


Subject(s)
HIV Infections/virology , HIV-1/classification , HIV-1/genetics , Molecular Typing/methods , Adult , Aged , DNA Primers/genetics , Genetic Variation , Genotype , HIV-1/isolation & purification , Humans , Male , Middle Aged , Molecular Sequence Data , Senegal , Sequence Analysis, DNA , Young Adult
9.
Biol Reprod ; 78(4): 697-704, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18094362

ABSTRACT

Transferrin is well known as an iron transport glycoprotein. Dimeric or tetrameric transferrin forms have recently been reported to modulate phagocytosis by human leukocytes. It is mainly synthesized by the liver, and also by other sources, such as Sertoli cells of the testis. Sertoli cells show a strong phagocytic activity toward apoptotic germ cells and residual bodies. Here, we provide evidence that purified human dimeric transferrin from commercial sources decreased residual body phagocytosis, unlike monomeric transferrin. The presence of iron appeared essential for dimeric transferrin inhibitory activity. Importantly, dimeric transferrin could be visualized by immunoblotting in Sertoli cell lysates as well as in culture media, indicating that dimeric transferrin could be physiologically secreted by Sertoli cells. By siRNA-mediated knockdown, we show that endogenous transferrin significantly inhibited residual body ingestion by Sertoli cells. These results are the first to identify dimeric transferrin in Sertoli cells and to demonstrate its implication as a physiological modulator of residual body phagocytosis by Sertoli cells.


Subject(s)
Phagocytosis/drug effects , Sertoli Cells/physiology , Transferrin/pharmacology , Animals , Cells, Cultured , Dimerization , Humans , Immunoblotting , Iron/pharmacology , Iron/physiology , Male , RNA, Small Interfering/genetics , Rats , Rats, Wistar , Sertoli Cells/chemistry , Sertoli Cells/drug effects , Structure-Activity Relationship , Transfection , Transferrin/chemistry , Transferrin/genetics
10.
J Neurosci Res ; 83(3): 403-14, 2006 Feb 15.
Article in English | MEDLINE | ID: mdl-16400659

ABSTRACT

Transferrin (Tf), the iron transport glycoprotein found in biological fluids of vertebrates, is synthesized mainly by hepatocytes. Tf is also synthesized by oligodendrocytes (Ol), and several lines of evidence indicate that brain Tf could be involved in myelinogenesis. Because Tf is postnatally expressed in the brain, we sought to investigate whether Tf could intervene in Ol differentiation. For this purpose, we analyzed transgenic mice overexpressing the complete human Tf gene in Ol. We show that the hTf transgene was expressed only from 5 days postpartum onward. In the brain of 14-day-old transgenic mice, the DM-20 mRNA level was decreased, whereas the PLP, MBP, CNP, and MAG mRNA levels were increased. We counted a higher proportion of Ol expressing the O4 (Ol-specific antigens) and PLP in brain cells cultured from transgenic mice. These results support the idea that overexpressing Tf in the brain accelerates the oligodendrocyte lineage maturation. Accordingly, by NMR imaging acquisition of diffusion tensor in hTf transgenic mice, we observed early maturation of the cerebellum and spinal cord and more myelination in the corpus callosum. In addition, hTf overexpression led to an increase in Sox10 mRNA and protein. Increases in Sox10 and in Tf expression occur simultaneously during brain development. The Olig1 mRNA level also increased, but long after the rise of hTf and Sox10. The Olig2 mRNA level remained unchanged in the brain of transgenic mice. Our findings suggest that Tf could influence oligodendrocyte progenitor differentiation in the CNS.


Subject(s)
Cell Differentiation/genetics , Gene Expression Regulation, Developmental/genetics , Mice, Transgenic/physiology , Oligodendroglia/cytology , Transferrin/genetics , 2',3'-Cyclic-Nucleotide Phosphodiesterases/genetics , 2',3'-Cyclic-Nucleotide Phosphodiesterases/metabolism , Age Factors , Analysis of Variance , Animals , Animals, Newborn , Blotting, Northern/methods , Blotting, Western/methods , Body Weight/genetics , Brain/cytology , Cell Count/methods , Cells, Cultured , Enzyme-Linked Immunosorbent Assay/methods , Humans , Immunohistochemistry/methods , Magnetic Resonance Imaging/methods , Mice , Mice, Inbred C57BL , Myelin Basic Protein/genetics , Myelin Basic Protein/metabolism , Myelin Proteolipid Protein/genetics , Myelin Proteolipid Protein/metabolism , Myelin-Associated Glycoprotein , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Oligodendroglia/physiology , RNA, Messenger/isolation & purification , Radioimmunoassay/methods , Receptors, Cell Surface/genetics , Receptors, Cell Surface/metabolism , Transferrin/metabolism
11.
Mol Endocrinol ; 19(7): 1812-20, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15774499

ABSTRACT

FSH is a major hormonal input that drives Sertoli cells to their fully differentiated function in male reproduction. It is a physiologically important issue to define how FSH mediates its effects at the cellular level to regulate gene expression. FSH biological activities are transduced via a seven-spanned transmembrane receptor, the FSH-R, primarily leading to cAMP-dependent protein kinase A (PKA) activation and cAMP response element binding protein-mediated transcriptional responses. Nevertheless, the intracellular mechanisms interacting with PKA to control Sertoli cell differentiation by FSH are still incompletely defined. Here, we report that, in primary cultures of Sertoli cells isolated from prepubertal rats, FSH enhanced p70S6K enzymatic activity, in a PKA-dependent manner. p70S6K was constitutively phosphorylated on Thr 389, in a manner sensitive to inhibitors of phosphatidyl-inositide-3 kinase and mammalian target of rapamycin. But FSH could not enhance p70S6K phosphorylation on Thr 389. Rather, the hormone induced the dephosphorylation of Thr 421/Ser 424, located in the autoinhibitory domain of p70S6K, in a PKA-dependent manner. Consistently, FSH-induced phosphorylation of the S6 ribosomal protein, a cellular substrate of p70S6K, required PKA activity. In conclusion, these results show that FSH triggers unexpected regulations of p70S6K by dephosphorylation of Thr 421/Ser 424 mediated by PKA, and stimulates S6 phosphorylation, in Sertoli cells.


Subject(s)
Cyclic AMP-Dependent Protein Kinases/metabolism , Follicle Stimulating Hormone/physiology , Ribosomal Protein S6 Kinases, 70-kDa/metabolism , Sertoli Cells/enzymology , Animals , Enzyme Activation , Follicle Stimulating Hormone/pharmacology , Male , Phosphoinositide-3 Kinase Inhibitors , Phosphorylation , Protein Kinases/drug effects , Rats , Serine/metabolism , Sertoli Cells/drug effects , Sirolimus/pharmacology , TOR Serine-Threonine Kinases , Threonine/metabolism
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