Studies on the potential use of CD38 expression as a marker for the efficacy of anti-retroviral therapy in HIV-1-infected patients in Thailand

AbstractThe monitoring of the efficacy of anti-retroviral therapy (ART) is becoming an important issue in the developing world. The current use of CD4 counts, plasma viral loads, and monitoring of drug-resistant viruses are at present either uninformative or costly. Thus, more new cost-effective and practical techniques need to be established and implemented. Towards this goal, our lab has carried out studies on the potential use of CD38 frequency and density expression by flow analysis as a means to assess the efficacy of ART. Results of our studies using whole blood sample from normal healthy donors indicate that CD38 is expressed by a high frequency of not only CD4+ and CD8+ T cells but also most hematopoietic cell lineages analyzed. Detailed studies of CD38 expression along with other cell surface markers using whole blood sample from HIV-1-infected patients showed that the most discriminating change was the increased frequency and density of CD38 expression by CD3+CD8+ T cells. Of importance was our preliminary finding that a reversal of the increased frequency and density of CD38 expression by CD8+ T cells only appeared in the whole blood sample from patients who were responders to ART but not those who were drug failures. These initial data provide a platform and incentive for larger cohort studies including prospective pre- and post-ART for the institution of such monitoring techniques in resource limited settings

Detection of in vivo hepatitis B virus surface antigen mutations—A comparison of four routine screening assays

An important requirement for a state-of-the-art hepatitis B surface antigen (HBsAg) screening assay is reliable detection of mutated HBsAg. Currently, there is a striking shortage of data regarding the detection rates of in vivo HBsAg mutations for these clinically important assays. Therefore, we compared the detection rates of four commercial HBsAg screening assays using a global cohort of 1553 patients from four continents with known HBV genotypes. These samples, which represent the broadest spectrum of known and novel HBsAg major hydrophilic region (MHR) mutations to date, were analyzed for the presence of HBsAg using the Roche Elecsys® HBsAg II Qualitative, Siemens ADVIA Centaur XP HBsAg II, Abbott Architect HBsAg Qualitative II and DiaSorin Liaison® HBsAg Qualitative assays, respectively. Of the 1553 samples, 1391 samples could be sequenced; of these, 1013 (72.8%) carried at least one of the 345 currently known amino acid substitutions (distinct HBsAg mutation) in the HBsAg MHR. All 1553 patient samples were positive for HBsAg using the Elecsys® HBsAg II Qual assay, with a sensitivity (95% confidence interval) of 99.94% (99.64%-100%), followed by the Abbott Architect 99.81% (99.44%-99.96%), Siemens ADVIA 99.81% (99.44%-99.96%) and DiaSorin Liaison® 99.36% (98.82%-99.69%) assays, respectively. Our results indicate that the Elecsys® HBsAg II Qual assay exhibits the highest sensitivity among the commercial HBsAg screening assays, and demonstrate that its capacity to detect HBV infection is not compromised by HBsAg MHR mutants

Serological Response to the 2009 Pandemic Influenza A (H1N1) Virus for Disease Diagnosis and Estimating the Infection Rate in Thai Population

BACKGROUND: Individuals infected with the 2009 pandemic virus A(H1N1) developed serological response which can be measured by hemagglutination-inhibition (HI) and microneutralization (microNT) assays. METHODOLOGY/PRINCIPAL FINDINGS: MicroNT and HI assays for specific antibody to the 2009 pandemic virus were conducted in serum samples collected at the end of the first epidemic wave from various groups of Thai people: laboratory confirmed cases, blood donors and health care workers (HCW) in Bangkok and neighboring province, general population in the North and the South, as well as archival sera collected at pre- and post-vaccination from vaccinees who received influenza vaccine of the 2006 season. This study demonstrated that goose erythrocytes yielded comparable HI antibody titer as compared to turkey erythrocytes. In contrast to the standard protocol, our investigation found out the necessity to eliminate nonspecific inhibitor present in the test sera by receptor destroying enzyme (RDE) prior to performing microNT assay. The investigation in pre-pandemic serum samples showed that HI antibody was more specific to the 2009 pandemic virus than NT antibody. Based on data from pre-pandemic sera together with those from the laboratory confirmed cases, HI antibody titers ≥ 40 for adults and ≥ 20 for children could be used as the cut-off level to differentiate between the individuals with or without past infection by the 2009 pandemic virus. CONCLUSIONS/SIGNIFICANCE: Based on the cut-off criteria, the infection rates of 7 and 12.8% were estimated in blood donors and HCW, respectively after the first wave of the 2009 influenza pandemic. Among general population, the infection rate of 58.6% was found in children versus 3.1% in adults

One-year experience of nucleic acid technology testing for human immunodeficiency virus Type 1, hepatitis C virus, and hepatitis B virus in Thai blood donations

Wstęp: Krew pobrana w 2007 roku w Narodowym Centrum Krwi Tajlandzkiego Stowarzyszenia Czerwonego Krzyża została zbadana metodami biologii molekularnej (NAT) za pomocą systemów: TIGRIS/Procleix Ultrio firmy Chiron oraz cobas s 201/cobas TaqScreen MPX firmy Roche. Materiał i metody: Oceny czułości, specyficzności oraz dokładności systemów dokonano przez zbadanie 486 676 seronegatywnych próbek krwi. W każdym dniu pobierania krwi próbki były dzielone na dwie części. Próbki oznaczone numerami nieparzystymi były badane pojedynczo (TIGRIS), podczas gdy próbki oznaczone parzystymi numerami badano w pulach 6 na aparacie cobas s 201. W celu potwierdzenia wyników reaktywnych badano w duplikacie próbki pobrane z pojemnika z osoczem i w ten sposób oceniano specyficzność testu. Reaktywne próbki były testowane na alternatywnym systemie NAT, a następnie badaniom poddano kolejne próbki pobrane od tych dawców. Wyniki: Czułość analityczna obu systemów osiągnęła 95-procentowy limit wykrywania, zgodnie z informacją załączoną przez producenta. Nie zaobserwowano krzyżowej kontaminacji w żadnym z testowanych systemów. Specyficzność wyniosła odpowiednio 99,93% dla testu Procleix Ultrio i 99,90% dla testu cobas TaqScreen. W wyniku zastosowania technik NAT, ludzki wirus niedoboru odporności typu 1 (HIV-1) został wykryty statystycznie u 1 na 97 000 przebadanych dawców, wirus zapalenia wątroby typu C - u 1 na 490 000 przebadanych dawców, a wirus zapalenia wątroby typu B (HBV) - u 1 na 2800 przebadanych dawców krwi. Zidentyfikowano również kilku utajonych nosicieli HBV, z których większość została wykryta za pomocą obu testów. Przypadki okienka serologicznego dla HIV-1 i HCV zostały wykryte przez oba testy. Wnioski: Wyniki przeprowadzonych badań wykazały, że obydwa systemy i testy nadają się do prowadzenia rutynowych badań NAT przez Narodowe Centrum Krwi Tajlandzkiego Stowarzyszenia Czerwonego Krzyża, chociaż test Procleix Ultrio okazał się mniej czuły w przypadku wykrywania HBV, w porównaniu z testem TaqScreen.Background: Blood donations collected at the National Blood Center, the Thai Red Cross Society, Bangkok, in 2007 were tested by nucleic acid amplification technology (NAT) using the Chiron TIGRIS/Procleix Ultrio test and the Roche cobas s 201/cobas TaqScreen multiplex test. Material and methods: The sensitivity, specificity, and robustness were determined by testing 486 676 seronegative blood donations. Samples from each day of collection were divided into two sets; the odd-numbered samples were tested individually on the TIGRIS and the evennumbered samples were tested in pools of 6 on the cobas s 201. The status of reactive samples was confirmed by duplicate testing of samples from the plasma bag to calculate the test specificity. Reactive samples were tested on the alternate system and followed up. Results: The analytical sensitivity of both systems met the 95% limits of detection claimed by the respective package inserts. No cross contamination was seen with either system. Test specificity was 99.93 and 99.90% for the Procleix Ultrio and cobas TaqScreen tests, respectively. The NAT yield rates for human immunodeficiency virus Type 1 (HIV-1), hepatitis C virus (HCV), and hepatitis B virus (HBV) were 1:97 000, 1:490 000, and 1:2800, respectively. Several occult HBV donors, the majority of whom were detected by both tests, were also identified. The HIV-1 and HCV window cases were detected with both tests. Conclusion: The performances of the systems and tests indicated that both were acceptable for routine NAT by the National Blood Center, the Thai Red Cross Society. However, the Procleix Ultrio test appeared to be less sensitive than the cobas TaqScreen test for HBV

An avian influenza A(H11N1) virus from a wild aquatic bird revealing a unique Eurasian-American genetic reassortment

Influenza surveillance in different wild bird populations is critical for understanding the persistence, transmission and evolution of these viruses. Avian influenza (AI) surveillance was undertaken in wild migratory and resident birds during the period 2007–2008, in view of the outbreaks of highly pathogenic AI (HPAI) H5N1 in poultry in India since 2006. In this study, we present the whole genome sequence data along with the genetic and virological characterization of an Influenza A(H11N1) virus isolated from wild aquatic bird for the first time from India. The virus was low pathogenicity and phylogenetic analysis revealed that it was distinct from reported H11N1 viruses. The hemagglutinin (HA) gene showed maximum similarity with A/semipalmatedsandpiper/Delaware/2109/2000 (H11N6) and A/shorebird/Delaware/236/2003(H11N9) while the neuraminidase (NA) gene showed maximum similarity with A/duck/Mongolia/540/2001(H1N1). The virus thus possessed an HA gene of the American lineage. The NA and other six genes were of the Eurasian lineage and showed closer relatedness to non-H11 viruses. Such a genetic reassortment is unique and interesting, though the pathways leading to its emergence and its future persistence in the avian reservoir is yet to be fully established

Prevalence of Hepatitis B Virus (HBV) Infection Among Hmong Immigrants in the San Joaquin Valley

Chronic hepatitis B infection (HBV) is the major cause of primary liver cancer worldwide and Asians are disproportionately affected. The prevalence of HBV among most Asian American groups has been well documented, except in Hmong immigrants in the United States. The aim of this study was to determine the prevalence of HBV among Hmong immigrants in the San Joaquin Valley of California. A convenient sample of 534 Hmong age ≥18 years was recruited at various locations throughout Fresno County. Blood samples from study participants were collected and tested for hepatitis B surface antigen (HBsAg) by enzyme-immunoassay. Two hundred and eighty-nine females and 245 males of Hmong descent (mean age, 43.93) were screened. Eighty-nine (41 males and 48 females) were positive for HBsAg, which accounts for a prevalence of 16.7% (95% C.I. 13.5–19.9). The majorities of HBsAg positive patients were ≥40 years (64.2%), married (66.7%), born in Laos (87.3%), and had lived in the United States ≥20 years (62.5%). Only 37.5% of the participants reported having a primary care physician. Our study revealed that approximately one out of every six Hmong immigrants screened was infected with HBV. Based on our findings, more than one-third of these infected patients have no primary care physician to provide further treatment, surveillance for liver cancer, or vaccination of their families. This supports the Institute of Medicine’s recent recommendations to the Center for Disease Control to engage in a national Hepatitis B surveillance system

Comparison of the technical and clinical performance of the Elecsys® HBsAg II Assay with the Architect®, AxSym®, and Advia® centaur HBsAg screening assays

10.1002/jmv.21706Journal of Medical Virology825755-76