The Significance of the Nucleic Acid Test (NAT) to Prevent Viral Contamination in Musculoskeletal Tissue Transplantation.

Objective The present study aims to highlight the significance of the nucleic acid test (NAT) for musculoskeletal tissue donation and to compare the sensitivity of this test on the different available platforms. Method The present study is a retrospective survey in a human tissue bank database and an integrative literature review encompassing the last 10 years. The PubMed portal and the SCOPUS, CINAHL, and Web of Science databases were queried for articles. Results We found no specific studies on the use and sensitivity of NAT in braindead tissue donors. The information presented in the present study consists of specific contents intended for the Brazilian Blood Transfusion Network (Hemorrede Transfusional Nacional, in Portuguese) and internal retrospective data from a tissue bank located at a city in the state of São Paulo, Brazil. Conclusions The NAT is effective in blood samples from living patients. However, since biochemical reactions in braindead patients can be different, specific research, platforms, or both are crucial to tissue banks.

The Significance of the Nucleic Acid Test (NAT) to Prevent Viral Contamination in Musculoskeletal Tissue Transplantation / A importância da realização do teste de ácidos nucleicos (NAT) para a prevenção de contaminação viral nos transplantes de tecidos musculoesqueléticos

Abstract Objective The present study aims to highlight the significance of the nucleic acid test (NAT) for musculoskeletal tissue donation and to compare the sensitivity of this test on the different available platforms. Method The present study is a retrospective survey in a human tissue bank database and an integrative literature review encompassing the last 10 years. The PubMed portal and the SCOPUS, CINAHL, and Web of Science databases were queried for articles. Results We found no specific studies on the use and sensitivity of NAT in braindead tissue donors. The information presented in the present study consists of specific contents intended for the Brazilian Blood Transfusion Network (Hemorrede Transfusional Nacional, in Portuguese) and internal retrospective data from a tissue bank located at a city in the state of São Paulo, Brazil. Conclusions The NAT is effective in blood samples from living patients. However, since biochemical reactions in braindead patients can be different, specific research, platforms, or both are crucial to tissue banks.

Resumo Objetivo Evidenciar a importância da realização do teste de ácido nucleico (NAT, na sigla em inglês) para doação de tecidos musculoesqueléticos, assim como comparar a sensibilidade deste exame nas diferentes plataformas existentes no mercado. Método Trata-se de um levantamento retrospectivo no banco de dados de um determinado Banco de Tecidos Humanos e de uma revisão integrativa da literatura, operacionalizada nos últimos 10 anos. As buscas de artigos ocorreram no portal PubMed e nas bases de dados SCOPUS, CINAHL e Web of Science. Resultados Não foram encontrados estudos específicos sobre a utilização e a sensibilidade do exame NAT em pacientes doadores de tecidos com morte encefálica (ME), sendo as informações apresentadas no presente estudo conteúdos específicos destinados à Hemorrede Transfusional Nacional e aos dados retrospectivos internos de um Banco de Tecidos do interior do estado de São Paulo, Brasil. Conclusões O exame NAT se apresenta efetivo em amostras de sangue de pacientes vivos. Porém, reações bioquímicas em pacientes com condições de ME podem se apresentar de formas diferenciadas, tornando-se indispensáveis a realização de pesquisas específicas e/ou a indicação de plataformas aos Bancos de Tecidos.

Following up and re-entry of HBV reactive blood donors in Yantai area / 中国输血杂志

【Objective】 To analyze the preliminary screening and follow-up testing data of HBV in Yantai area, and discuss the rationality of following up and re-entry program of HBV reactive blood donors. 【Methods】 Donors who were single reagent reactive by enzyme-linked immunosorbent assay (ELISA) in initial screening but non-reactive by nucleic acid testing (NAT) were followed up. Individual NAT(ID-NAT) was performed for HBV DNA, ELISA for HBsAg, HBsAb, HBeAb, HBeAg and HBcAb, and ECLIA for the detection of HBsAg. 【Results】 A total of 547 blood donors were HBsAg ELISA-/NAT+, and 97 were followed up, among which 24 met the requirements of re-entry while 73 did not. Of the 24 blood donors who met the re-entry requirements, 13 donated blood again, with test results all qualified. 【Conclusion】 The combination of ELISA, ID-NAT, and ECLIA methods for following up detection for HBsAg ELISA+ blood donors is recommended. Blood donors with HbsAb S/CO ≥ 10 and negative results for other tests met the re-entry requirements, with a re-entry rate at 24.74%, and the re-donation qualified rate of blood donors after re-entry was 100%.

Performance verification of domestic nucleic acid testing system in blood stations based on T/CSBT / 中国输血杂志

【Objective】 To explore the performance verification of the Shengxiang automatic NAT system for HBV DNA, HCV RNA and HIV RNA-1 using PCR-fluorescence in the laboratories of blood stations, in order to meet the requirements of T/CSBT and ensure the quality of nucleic acid detection. 【Methods】 Samples used in the external quality assessment (EQA) of National Center for Clinical Laboratories of the year 2022 were taken to verify the concordance. The standard materials of HBV DNA, HCV RNA and HIV RNA-1 were used to verify the analytical sensitivity, endogenous interfering substances, repeatability, anti-cross contamination ability and stability. 【Results】 The concordance rate of 20 EQA samples was 100%. The analytical sensitivity of HBV DNA, HCV RNA and HIV RNA-1 were all reactive and met T/CSBT. The yielding of HBV DNA, HCV RNA and HIV RNA-1 was affected little with lipemia at 3g/L and hemolysis at 4g/L. The coefficients of variation(CV) of intra-assay and inter-assay which met T/CSBT were all less than 5%, and the intra-assay variation coefficient was less than the inter-assay variation coefficient. The test results of 40 negative samples tested for cross contamination resistance were 100% negative, and 40 positive samples of HBV with 10 000 IU/mL were 100% positive. The stability verification results showed that the detection rate of weak positive samples was 100%. The coefficient of variation of the test results of the reagent after 1 and 5 freeze-thaw cycles were less than 5%,and the difference between the detection Ct value of reagent underwent once freeze-thaw and five-time freeze-thaw was not statistically significant. 【Conclusion】 The analytical sensitivity,endogenous interfering substances, repeatability,anti-cross contamination ability,stability and the compliance rate of domestic Shengxiang Gene automatic NAT system and supporting reagents by PCR-fluorescence method all meet T/CSBT, so it can be used for nucleic acid detection in blood screening in blood station laboratory.

PCR to CRISPR: Role of Nucleic Acid Tests (NAT) in detection of COVID-19.

COVID-19 infection has emerged as an unparalleled pandemic with morbidity and mortality tolls challenging diagnostic approaches and therapeutic interventions, and raising serious questions for healthcare policy-makers. From the diagnostic perspective, Reverse transcriptase polymerase chain reaction remains the gold standard. However, issues associated with gene primer variation in different countries, low analytical sensitivity, cross-reactivity with certain human coronaviruses have raised serious concerns within the scientific community. Alongside longer turnaround times, requirements of sophisticated equipment and trained technicians are the other challenges for conventional reverse transcriptase polymerase chain reaction testing. The recent biotechnological boom has now allowed newer nucleic acid testing options for diagnosing severe acute respiratory syndrome Coronovairus 2 (SARS-CoV2) with much better diagnostic efficiency, reduced turnaround times and possible benefit for use as a point-of-care test. Isothermal techniques with simple equipment requirements along with uniform temperature for analysis have emerged to be more sensitive and specific with turnaround times as low as 10-15 minutes. Similarly, Cluster Regularly Interspaced Short Palindromic Repeats have also been seen to play a very decisive role in COVID-19 diagnostics with much superior diagnostic efficiency and feasibility as a point-of-care test and its possible use for sequencing. The current narrative review was planned to consolidate data for all possible nucleic acid testing options under research/clinical use, and to provide a comparative assessment from the perspective of both the clinician and the laboratory.

Results of a SARS-CoV-2 virus genome detection external quality assessment round focusing on sensitivity of assays and pooling of samples.

OBJECTIVES: Results of earlier external quality assessment (EQA) rounds suggested remarkable differences in the sensitivity of SARS-CoV PCR assays. Although the test systems are intended to detect SARS-CoV-2 in individual samples, screening is often applied to sample pools to increase efficiency and decrease costs. However, it is unknown to what extent these tests actually meet the manufacturer's specifications for sensitivity and how they perform when testing sample pools. METHODS: The sensitivity of assays in routine use was evaluated with a panel of positive samples in a round of a SARS-CoV-2 virus genome detection EQA scheme. The panel consisted of samples at or near the lower limit of detection ("weakly positive"). Laboratories that routinely test sample pools were asked to also analyze the pooled EQA samples according to their usual pool size and dilution method. RESULTS: All participants could detect a highly positive patient-derived sample (>106 copies/mL). Most (96%) of the test systems could detect at least 1,000 copies/mL, meeting the minimum acceptable benchmark, and many (94%) detected the vRNA in a sample with lower concentration (500 copies/mL). The false negative ratio increased to 16 and 26% for samples with 100 and 50 copies/mL, respectively. CONCLUSIONS: The performance of most assays met or exceeded their specification on sensitivity. If assays are to be used to analyze sample pools, the sensitivity of the assay and the number of pooled samples must be balanced.

Biotechnological Perspectives to Combat the COVID-19 Pandemic: Precise Diagnostics and Inevitable Vaccine Paradigms.

The outbreak of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause for the ongoing global public health emergency. It is more commonly known as coronavirus disease 2019 (COVID-19); the pandemic threat continues to spread aroundthe world with the fluctuating emergence of its new variants. The severity of COVID-19 ranges from asymptomatic to serious acute respiratory distress syndrome (ARDS), which has led to a high human mortality rate and disruption of socioeconomic well-being. For the restoration of pre-pandemic normalcy, the international scientific community has been conducting research on a war footing to limit extremely pathogenic COVID-19 through diagnosis, treatment, and immunization. Since the first report of COVID-19 viral infection, an array of laboratory-based and point-of-care (POC) approaches have emerged for diagnosing and understanding its status of outbreak. The RT-PCR-based viral nucleic acid test (NAT) is one of the rapidly developed and most used COVID-19 detection approaches. Notably, the current forbidding status of COVID-19 requires the development of safe, targeted vaccines/vaccine injections (shots) that can reduce its associated morbidity and mortality. Massive and accelerated vaccination campaigns would be the most effective and ultimate hope to end the COVID-19 pandemic. Since the SARS-CoV-2 virus outbreak, emerging biotechnologies and their multidisciplinary approaches have accelerated the understanding of molecular details as well as the development of a wide range of diagnostics and potential vaccine candidates, which are indispensable to combating the highly contagious COVID-19. Several vaccine candidates have completed phase III clinical studies and are reported to be effective in immunizing against COVID-19 after their rollout via emergency use authorization (EUA). However, optimizing the type of vaccine candidates and its route of delivery that works best to control viral spread is crucial to face the threatening variants expected to emerge over time. In conclusion, the insights of this review would facilitate the development of more likely diagnostics and ideal vaccines for the global control of COVID-19.

Clinical evaluation of the Procleix SARS-CoV-2 assay, a sensitive, high-throughput test that runs on an automated system.

Testing is crucial in controlling COVID-19. The Procleix® SARS-CoV-2 assay, a transcription-mediated amplification nucleic acid test that runs on an automated system, was evaluated using inactivated virus and clinical samples. The sensitivity of the assay was assessed using heat-inactivated SARS-CoV-2 and compared to 3 other tests. Clinical validation utilized 2 sets of samples: (1) Nasal, nasopharyngeal and oropharyngeal samples (n = 963) from asymptomatic individuals, and (2) nasopharyngeal samples from symptomatic patients: 100 positive and 100 negative by RT-PCR. The Procleix assay had greater sensitivity (3-fold to 100-fold) than the comparators and had high specificity (100%) in asymptomatic subjects. In symptomatic patients, the Procleix assay detected 100% of PCR-positives and found 24 positives in the initial PCR-negatives. Eighteen of these were confirmed positive and 6 were inconclusive. These studies showed that the Procleix SARS-CoV-2 assay was a sensitive and specific tool for detecting COVID-19.

Detection ability of nucleic acid screen laboratory in blood bank based on NCCL external quality assessment data / 中国输血杂志

【Objective】 To evaluate the laboratory's NAT ability by analyzing the feedback reports of nucleic acid test (NAT) results of external quality assessment (EQA) of National Center for Clinic Laboratories (NCCL), so as to improve the laboratory management details and ensure blood safety. 【Methods】 The data of NCCL NAT EQA of blood screening laboratory of Tianjin Blood Center (a total of five occasions from Jan 2019 to Jun 2021) were statistically analyzed. 【Results】 From Jan 2019 to Jun 2021, the laboratory participated in EQA for five times and all the results were qualified. The test results of NAT EQA HIV RNA/HCV RNA/HBV DNA detected by R1, R2 and R4 were consistent with the reference results. R3 showed false positive results (CT value 40.46) in the single donation detection of sample No.1925 in HCV RNA. Unreported data of the laboratory was that in the first EQA in 2021, the R4 showed false positive results (CT value 35.8) in in the single donation detection of sample No.2113 in HIV RNA. 【Conclusion】 The performance of each NAT screening system in our laboratory is relatively stable except occasional false positive results influenced by every factor. Potential problems can be found and continuously improved by assaying EQA reports and the extended experimental results of EQA samples to further improve the detection ability.

Performance verification of nucleic acid testing project based on ISO 15189 / 中国输血杂志

【Objective】 To explore the performance verification of NAT and its procedures for HBV DNA, HCV RNA and HIV RNA-1 using PCR-fluorescence via Cobas s201 automatic NAT system and supporting MPX V2.0 reagents that applied in the laboratories of blood stations, in order to satisfy ISO 15189 accreditation requirements and ensure the accuracy of NAT results. 【Methods】 Samples used in external quality assessment(EQA) of year 2020 were taken to verify the concordance, Performance evaluation panel and sensitivity verification panel of Roche second-generation NAT system were used to verify the sensitivity/ specificity and the lower limit of detection, respectively.And HBV DNA, HCV RNA and HIV RNA-1 quality control products were used to verify the anti-interference ability. 【Results】 The concordance rate of 40 EQA, samples was 100%. The sensitivity and specificity of Cobas s201 automatic NAT system and supporting MPX V2.0 reagents in detecting HBV DNA, HCV RNA and HIV RNA-1 were all 100%. The lower detection limit for HBV DNA, HCV RNA and HIV RNA-1 all met the requirements of reagent instructions. The yielding of HBV DNA, HCV RNA and HIV RNA-1 were affected little with hemolysis at 500 mg/dL but interfered seriously as lipemia reached 3 300 mg/dL. 【Conclusion】 The concordance rate, sensitivity, specificity and lower detection limit of the Cobas s201 fully-automatic NAT system and MPX V2.0 reagents by PCR-fluorescence method all met the requirements of reagent instructions. The verification of anti-interference ability demonstrated the requirements of ISO 15189 and the needs of blood station laboratories could be satisfied, and the detection methods and procedures can ensure the accuracy of NAT results.

Transplantation of Kidneys From Hepatitis C Virus-Infected Donors to Hepatitis C Virus-Negative Recipients: One-Year Kidney Allograft Outcomes.

RATIONALE & OBJECTIVE: Transplant centers in the United States are increasingly willing to transplant kidneys from hepatitis C virus (HCV)-infected (HCV+) donors into HCV- recipients. We studied the association between donor HCV infection status and kidney allograft function and posttransplantation allograft biopsy findings. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: We examined 65 HCV- recipients who received a kidney from a HCV+ donor and 59 HCV- recipients who received a kidney from a HCV- donor during 2018 at a single transplant center. EXPOSURE: Predictor(s) of donor infection with HCV. OUTCOMES: Kidney allograft function and allograft biopsy findings during the first year following transplantation. ANALYTICAL APPROACH: We compared estimated glomerular filtration rate (eGFR), findings on for-cause and surveillance protocol biopsies, development of de novo donor-specific antibodies (DSAs), and patient and allograft outcomes during the first year following transplantation between recipients of HCV+ and HCV- kidneys. We used linear regression to estimate the independent association between allograft function and HCV viremic status of the kidney donor. RESULTS: The mean age of recipients was 52 ± 11 (SD) years, 43% were female, 19% and 80% of recipients were White and Black, respectively. Baseline characteristics were similar between the HCV+ and HCV- groups. There were no statistically significant differences between the HCV+ and HCV- groups in delayed graft function rates (12% vs 8%, respectively); eGFRs at 3, 6, 9, and 12 months post-transplantation; proportions of patients with cellular rejection (6% vs 7%, respectively); and proportions with antibody-mediated rejection (7% vs 10%, respectively) or de novo DSAs (31% vs 20%, respectively). HCV viremic status was not associated with eGFR at 3, 6, 9, or 12 months. LIMITATIONS: Generalizability from a single-center study and small sample size was limited. CONCLUSIONS: Recipients of kidneys from donors infected with HCV had similar kidney allograft function and probability of rejection in the first year after transplantation compared to those who received kidneys from donors without HCV infection.

NAT results of HBV and HCV under different vacuum collection tubes, storage temperature and storage time / 中国输血杂志

【Objective】 To verify the results of HBV DNA and HCV RNA screening under different brands of vacuum collection tubes for blood samples, storage temperature and storage time. 【Methods】 Experiment 1 was conducted as follows: blood samples were collected simultaneously from 52 voluntary blood donors using two brands(divided into group A and group B) of vacuum collection tubes for blood samples. The plasma separation of group A and group B were compared, and the effects of storage time on the NAT yield of HBV DNA and HCV RNA were statistically analyzed. Experiment 2 was conducted as follows: the effects of different storage temperature, time and tubes on the NAT yield of HBV DNA and HCV RNA samples with low viral load in group A and B were verified and compared in the simulated phlebotomy condition. 【Results】 In Experiment 1: After centrifugation, blood plasma layer and cells layer were separated completely in group A(100%, 52/52), but one sample was not well separated in group B(1/52, 1.92%). After 4 to 10 h after collection, blood samples of two groups were centrifuged and screened for HBV DNA, HCV RNA within 24 h. No positive samples were yielded and the Ct values of internal control(IC-DNA and IC-RNA) were uniform. In Experiment 2: Whole blood samples, stored for either 4 h or 6~10 h at 4 ℃ or 25℃ before centrifugation, showed no difference on the NAT-yield of HBV DNA nor HCV RNA samples with low viral load(P>0.05). Ct values of HBV DNA and HCV RNA of group A was similar to those of group B as centrifuged samples were stored for 24 h or 72~104 h at 4℃(P>0.05), but all increased as the storage time prolonged. Ct values of HBV DNA in group A increased from 33.45±0.29(24 h) to 33.82±0.08(72~104 h) and HCV RNA from 35.21±0.20 to 36.12±0.43; HBV DNA from 33.46±0.25 to 34.30±0.60 and HCV RNA from 35.47±0.24 to 36.49±0.51 in group B. 【Conclusion】 Under certain laboratory condition, different storage time, storage temperature and tubes shed few effect on the NAT-yield of HBV DNA and HCV RNA samples with low virus loads. However, it is suggested that the blood sample be detected within 72 h after centrifugation at 4 ℃ storage.

Serologic Response to SARS-CoV-2 in COVID-19 Patients with Different Severity.

The immense patient number caused by coronavirus disease 2019 (COVID-19) global pandemic brings the urge for more knowledge about its immunological features, including the profile of basic immune parameters. In this study, eighty-eight reported COVID-19 patients in Wuhan were recruited from January to February, 2020, including 32 severe/critical cases and 56 mild/moderate cases. Their mean age was 56.43 years (range 17-83) and gender ratio (male/female) was 43:45. We tested SARS-CoV-2 RNA with commercial kits, investigated the level of serologic IgM and IgG antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using magnetic particle chemiluminescence immunoassays, and compared the results of serologic tests and nucleic acid test (NAT). Among 88 patients, 95.45% were confirmed as positive by the combination of NAT and antibody test, which was significantly higher (P < 0.001) than by single nucleic acid test (73.86%) or serologic test (65.91%). Then the correlation between temporal profile and the level of antibody response was analyzed. It showed that seroconversion started on day 5 after disease onset and IgG level was rose earlier than IgM. Comparison between patients with different disease severity suggested early seroconversion and high antibody titer were linked with less severe clinical symptoms. These results supported the combination of serologic testing and NAT in routine COVID-19 diagnosis and provided evidence on the temporal profile of antibody response in patients with different disease severity.

An ultra-sensitive Abbott ARCHITECT® assay for the detection of hepatitis B virus surface antigen (HBsAg).

BACKGROUND: Critical to the identification of HBV infection and the prevention of transfusion transmitted disease is the sensitive and accurate detection of Hepatitis B virus surface antigen (HBsAg). Improvements in HBsAg assay sensitivity approaching the performance of nucleic acid testing (NAT) are essential to further reduce the detection window for acute HBV infection in regions where NAT is not widely available. OBJECTIVES AND STUDY DESIGN: An improved HBsAg assay on the fully-automated Abbott ARCHITECT® platform was developed to improve sensitivity, mutant and genotype detection. RESULTS: The analytical sensitivity of the improved prototype assay is 5.2 mIU/ml, which is 3.86- to 14.54-fold more sensitive than comparator assays based on the WHO International Reference Standard. The enhanced sensitivity was also demonstrated with 27 HBV seroconversion panels, detecting more panel members (191 of 364) vs. the ARCHITECT® Qual I (144), Qual II (160) and PRISM® (148) HBsAg assays. Further, the assay detected 7 of 12 HBV DNA positive/HBsAg negative samples, and detected all evaluated mutants and genotypes with higher sensitivity than the comparator assays. The improvement in sensitivity did not diminish assay specificity, attaining 100% (95% CI, 99.97-100%) on 10,633 blood donors. CONCLUSIONS: An Abbott ARCHITECT® HBsAg assay with clinical performance approaching that of mini-pool NAT (approximately 100 copies/ml was developed. The assay has superior HBsAg mutant and genotype detection and specificity, all of which are important for the diagnosis and management of HBV infection.

Novel bead-based platform for direct detection of unlabelled nucleic acids through Single Nucleobase Labelling.

Over the last decade, circulating microRNAs have received attention as diagnostic and prognostic biomarkers. In particular, microRNA122 has been demonstrated to be an early and more sensitive indicator of drug-induced liver injury than the widely used biomarkers such as alanine aminotransferase and aspartate aminotransferase. Recently, microRNA122 has been used in vitro to assess the cellular toxicity of new drugs and as a biomarker for the development of a rapid test for drug overdose/liver damage. In this proof-of-concept study, we report a PCR-free and label-free detection method that has a limit of detection (3 standard deviations) of 15 fmoles of microRNA122, by integrating a dynamic chemical approach for "Single Nucleobase Labelling" with a bead-based platform (Luminex®) thereby, in principle, demonstrating the exciting prospect of rapid and accurate profiling of any microRNAs related to diseases and toxicology.

High rate of missed HIV infections in individuals with indeterminate or negative HIV western blots based on current HIV testing algorithm in China.

It remains unclear if China's current HIV antibody testing algorithm misses a substantial number of HIV infected individuals. Of 196 specimens with indeterminate or negative results on HIV western blot (WB) retrospectively examined by HIV-1 nucleic acid test (NAT), 67.57% (75/111) of indeterminate WB samples, and 16.47% (14/85) of negative WB samples were identified as NAT positive. HIV-1 loads in negative WB samples were significantly higher than those in indeterminate WB samples. Notably, 86.67% (13/15) of samples with negative WB and double positive immunoassay results were NAT positive. The rate of HIV-1 infections missed by China's current HIV testing algorithm is unacceptably high. Thus, China should consider using NAT or integrating fourth generation ELISA into current only antibodies-based HIV confirmation. J. Med. Virol. 88:1462-1466, 2016. © 2016 Wiley Periodicals, Inc.

Novel biochip platform for nucleic acid analysis.

This manuscript describes the use of a novel biochip platform for the rapid analysis/identification of nucleic acids, including DNA and microRNAs, with very high specificity. This approach combines a unique dynamic chemistry approach for nucleic acid testing and analysis developed by DestiNA Genomics with the STMicroelectronics In-Check platform, which comprises two microfluidic optimized and independent PCR reaction chambers, and a sequential microarray area for nucleic acid capture and identification by fluorescence. With its compact bench-top "footprint" requiring only a single technician to operate, the biochip system promises to transform and expand routine clinical diagnostic testing and screening for genetic diseases, cancers, drug toxicology and heart disease, as well as employment in the emerging companion diagnostics market.