The Prevalence of Human T-Lymphotropic Virus Infection among Blood Donors in Southeast China, 2004-2013

Background

The human T-lymphotropic virus type 1 (HTLV-1) which is associated with the diseases of adult T-cell leukemia/lymphoma, HTLV-1 associated myelopathy / tropical spastic paraparesis (HAM/TSP) and HTLV-associated uveitis, can cause transfusion-transmitted infections. Although HTLV screening of blood donors was already routinely performed in developed countries, little is know about the HTLV prevalence among blood donors in developing countries which do not perform HTLV screening, such as China.

Objectives &Aims

To systematically characterize the prevalence of HTLV infection among bloods in southeast China.

Methods

A 10-year survey for HTLV prevalence in blood donors was performed in Xiamen, southeast China, during 2004-2013. The HTLV-1/2 of blood donations were screened by enzyme-linked immunosorbent assay, following with confirmation by western blot assay and 9nucleic acid testing. The HTLV-1 prevalences in donors from different cities were calculated. Viral sequences derived from identified HTLV-positive cases were sequenced and analyzed.

Results

Among 253,855 blood donors, 43 were confirmed to be seropositive for HTLV-1 (16.9 per 100,000 95% CI: 12.3-22.8) and none HTLV-2 infection was found. The HTLV-1 prevalence varied significantly in donors from different cities. Donors from cities in Fujian province (24.3 per 100,000, 95%CI: 17.4-33.1) had a significantly higher (p=0.001) HTLV-1 seroprevalence than those who were born in non-Fujian cities (3.4 per 100,000, 95%CI: 0.7-9.8). Among nine cities in Fujian province, the highest prevalence was found in blood donors from Ningde (171.3 per 100,000, 95%CI: 91.3-292.8) which is a coastal city in the northeast of Fujian. Molecular characterization of viral sequences from 27 HTLV-1 carriers revealed 25 were Transcontinental subtype of genotype A and 2 were Japanese subtype of genotype A. Interestingly, 12 of 25 Transcontinental subtype sequences harbored a characteristic L55P mutation in viral gp46 protein, which was only presented in the Transcontinental subtype sequences from Japan and Taiwan but not in that from other countries.

Conclusions

Although China is considered to be a non-endemic region for HTLV, the HTLV-1 prevalence in blood donors is significantly higher in Fujian province, southeast China. A higher prevalence of HTLV-1 in the Fujian may be attributed to endemic foci in the city of Ningde.     

Isolation,characterization, and transmission of human T-lymphotropic virus types I and II in culture

Highly sensitive coculture methods were developed both for isolation of human T-lymphotropic virus types I and II (HTLV-1 and HTLV-II) from infected individuals and for productive infection of lymphoid cells. Mitogen-activated peripheral blood mononuclear cells (PBMC) from 13 HTLV-I- and 20 HTLV-II-positive specimens were cocultured with an equal number of mitogen-activated PBMC from HTLV-seronegative individuals, and culture supernatants were tested for the presence of soluble p24^gag antigens at weekly intervals for 4 weeks. Eleven of 13 (85%) HTLV-I and 14 of 20 (70%) HTLV-II cultures were positive for p24 antigens. None of the 17 HTLV-seroindeterminate or six HTLV-seronegative specimens were positive for the presence of p24 antigen. The isolation rates for HTLV-I and HTLV-II by an alternative whole-blood lysis procedure were comparable to those obtained by standard PBMC cultures. Furthermore, cocultivation of PHA-stimulated PBMC from healthy donors with lethally irradiated HTLV-I- and HTLV-II-infected cell lines (SP and Mo-T, respectively) resulted in productive viral infection, as reflected by the appearance of p24^gag antigens concomitant with specific genomic amplification of HTLV proviral DNA after 3 weeks of cocultivation. Thus, the cocultivation technique provides a highly sensitive and specific procedure both for HTLV isolation and for infection of target cells.     

Prevalence of antibodies to human T cell leukaemia/lymphoma virus in blood donors in north London.

OBJECTIVES--To determine the prevalence of antibodies to the human T cell leukaemia/lymphoma viruses (HTLV-I and HTLV-II) in blood donors in north London in order to assess the economic impact and the logistic effects that routine screening would have on the blood supply. DESIGN--All donations collected by the north London blood transfusion centre between January 1991 and June 1991 were screened for antibodies to HTLV-I and HTLV-II by modified, improved Fujirebio gel particle agglutination test. Positive samples were titrated and retested as necessary. SUBJECTS--96,720 unpaid volunteers, who gave 105,730 consecutive donations of blood and plasma. SETTING--North London blood transfusion centre. MAIN OUTCOME MEASURE--Observed numbers of donors confirmed to be seropositive for HTLV by reference laboratories. RESULTS--Of 2622 (2.5%) initially reactive samples, 414 (0.4% of all samples) gave a titre of > or = 1 in 16 on the modified agglutination test. Thirty five of the 414 serum samples yielded positive results on one of two enzyme linked immunosorbent assays (ELISA (Cambridge Biotech and Abbot)), and none of these results were confirmed by either reference laboratory. Five samples yielded positive results on both ELISAs and all five of these were confirmed to contain antibodies to HTLV. One of the five contained antibodies to HTLV-II and the others antibodies to HTLV-I. Four seropositive donors were white women whose only risk factor for infection was sexual contact. The fifth (positive for antibodies to HTLV-II) was an Anglo-Caribbean man who admitted to previous misuse of intravenous drugs. CONCLUSION--The prevalence of antibodies to HTLV in blood donors in north London was one in 19,344 (0.005%). Up to 100 donors a year might be identified in the United Kingdom as being infected with HTLV, although prevalence in different regions may vary considerably.     

Seroprevalence of human T lymphtropic virus (HTLV) among tissue donors in Iranian tissue bank

Iranian Tissue Bank prepares a wide range of human tissue homografts such as; heart valve, bone, skin, amniotic membrane and other tissues for different clinical applications. The purpose of this study was to determine the seroprevalence of HTLV in tissue donors. About 1,548 tissue donors were studied during a 5-years period by ELISA assays. HTLV_1,2—antibodies were tested for all of donors with other tests upon American Association of Tissue Banks (AATB) standards. About 25 (1.61%) out of 1,548 tissue donors were HTLV positive that 17 donors were male and 8 were female (female/male ratio was approximately 47%). Regarding to the prevalence of HTLV among tissue donors and importance of cell and tissue safety and quality assurance, we recommend that all blood, cell and tissue banks should be involved both routine serological methods and other complementary tests such as polymerase chain reaction (PCR) for diagnosis of HTLV.     

Prevalence and evolutionary analyses of human T-cell lymphotropic virus in Guangdong province,China: Transcontinental and Japanese subtype lineages dominate the prevalence

To systematically characterize the prevalence and evolution of human T-cell lymphotropic virus (HTLV) infection among voluntary blood donors (BDs) in Guangdong province, China. A three-year survey for HTLV epidemiology among BDs was performed in Guangdong during 2016–2018. Anti-HTLV-1/2 was screened by ELISA and ECLIA, and subsequently confirmed by western blot (WB) and nucleic acid testing (NAT). The prevalence of HTLV in donors from different cities was calculated. The identified HTLV-positive cases were phylogenetically genotyped and analyzed in a Bayesian phylogenetic framework. Among 3,262,271 BDs, 59 were confirmed positive for HTLV-1 (1.81 per 100,000) and no HTLV-2 infection was found. The prevalence of HTLV-1 varied significantly among 21 cities in Guangdong province, China. The highest prevalence was found in donors from Shanwei (13.94 per 100,000), which is a coastal city in eastern Guangdong. Viral genomic sequences genotyped from 55 HTLV-1 carriers showed that 39 were transcontinental subtype and 16 were Japanese subtype. Specially, 13 out of 39 transcontinental subtype sequences were characterized with L55P mutation and 21 out of 55 sequences were characterized with L19F mutation in viral gp46 protein. The L55P mutation seemed be specific to eastern Asia since it only presented in the sequences from Japan, mainland China, and Taiwan. Phylogenetic analysis of gp46 gene shows that HTLV-1a may have been introduced to Guangdong through four different introduction events and formed major transmission clusters: clades I(13,602 years ago), II(16, 010 years ago), III(15,639 years ago) and IV(16,517 years ago). In general, Guangdong is considered to be a low-prevalence region for HTLV-1 infection, but the prevalence is significantly higher in Shanwei city. Transcontinental and Japanese subtype lineages dominate the prevalence in Guangdong. In terms of blood safety, HTLV antibody screening for first-time blood donors can effectively reduce the risk of HTLV transmission.     

Glucose-6-phosphate dehydrogenase deficiency and blood groups in northern Sardinia

Glucose-6-phosphate dehydrogenase deficiency, A1A2BO, Rhesus and Kell systems were investigated in a sample of 28,439 blood donors native of northern Sardinia. The frequency of deficient male individuals was 6.56%. Higher values of r, D, and CDe compared to the averages for continental Italy were observed. Variations within the island were found in the A1A2BO and Rhesus blood group systems.     

Increased seroreactivity to HERV-K10 peptides in patients with HTLV myelopathy

Background

Previously, we had shown that persons infected with human T-cell lymphoma leukemia virus 1 or 2 (HTLV-1 or 2) had an increased prevalence of antibodies to a peptide in the Pol protein of the retrovirus HERV-K10, homologous to a peptide in HTLV gp21 envelope protein. The prevalence rate was higher in those with myelopathy vs. non-myelopathy. We have now extended our observations to a cohort restricted to North America in whom the diagnosis of HTLV myelopathy was rigorously confirmed to also test for reactivity to another HERV-K10 peptide homologous to the HTLV p24 Gag protein.

Methods

Sera from 100 volunteer blood donors (VBD), 53 patients with large granular lymphocytic leukemia (LGLL), 74 subjects with HTLV-1 or 2 infection (58 non-myelopathy and 16 myelopathy) and 83 patients with multiple sclerosis (MS) were evaluated in ELISA assays using the above peptides.

Results

The HTLV myelopathy patients had a statistically significant increased prevalence of antibodies to both HERV-K10 peptides (87.5%) vs. the VBD (0%), LGLL patients (0%), MS patients (4.8%), and the HTLV positive non-myelopathy subjects (5.2%).

Conclusion

The data suggest that immuno-cross-reactivity to HERV-K10 peptides and/or transactivation of HERV-K10 expression by the HTLV Tax protein may be involved in the pathogenesis of HTLV-associated myelopathy/tropical spastic paraparesis and spastic ataxia.

     

Occurrence and frequency of transmission of naturally occurring simian retroviral infections (SIV,STLV, and SRV) at the CIRMF Primate Center,Gabon

Abstract: Among the primates held at the CIRMF Primate Center, Gabon, no serological sign of SIV infection could be demonstrated in 68 cynomolgus monkeys, 60 chimpanzees, nine gorillas, and 12 sun-tailed monkeys, while seven of 102 mandrills and six of 24 vervets were infected with SIV. Six mandrills, seven vervets and ten cynomolgus monkeys exhibited a full HTLV type 1 Western blot profile. The sera of two gorillas and one chimpanzee presented with a positive but not typical HTLV Western blot profile. The sera of the gorillas lacked p24 antibodies, and the chimpanzee had a Western blot profile evocative of HTLV-II. All attempts to amplify viruses from these animals by PCR were unsuccessful. Two other chimpanzees and seven gorillas presented with indeterminate HTLV Western blot profiles. In the mandrill colony, only male animals were STLV seropositive and no sexual transmission to females was observed. SIV infection was also more frequent in male than female mandrills and sexual transmission appeared to be a rare event. No SRV infection was observed in macaques.     

Prevalence and genetic characterisation of HTLV-1 and 2 dual infections in patients with pulmonary tuberculosis in Central-West Brazil

Human T-cell lymphotropic virus (HTLV) may impact the clinical course of tuberculosis (TB). Both infections are highly endemic in Brazil. The aim of this study was to assess the prevalence of HTLV-1/2 in TB patients in Central-West Brazil and to perform a genetic characterisation of the respective isolates. Of the 402 patients, six (1.49%) were positive for anti-HTLV and five (1.24%; 95% confidence interval: 0.46-3.05) were infected with HTLV-1/2. Genetic characterisation demonstrated that the four HTLV-1 isolates belonged to the Transcontinental subgroup A of the Cosmopolitan subtype a and that the HTLV-2 isolate belonged to subtype a (HTLV-2a/c). The prevalence of HTLV infection observed in this study is higher than that observed in local blood donors and the HTLV-1 and 2 subtypes identified are consistent with those circulating in Brazil.     

Prevalence of human T‐lymphotropic virus type 1 carriers among pregnant women in Hokkaido,Japan

As there is a risk of MTCT of HTLV‐1, the HSGP HTLV‐1 MTCT was organized in 2011. To determine how many pregnant women are infected with HTLV‐1 in Hokkaido, which is the northernmost and the second largest island in Japan with a population of 5 467 000 and 39 392 newborns in 2011, the HSGP HTLV‐1 MTCT asked all facilities that may care for pregnant women in Hokkaido in July 2013 to provide information on the number of pregnant women who underwent screening for anti‐HTLV‐1 antibody using particle agglutination or chemiluminescent enzyme immunoassay, and the numbers of those with positive, equivocal, and negative test results in the screening and confirmation tests using western blotting or PCR methods in 2012, respectively. A total of 111 facilities participated in this study and provided information on 33 617 pregnant women who underwent screening in 2012, corresponding to approximately 85% of all pregnant women who gave birth in Hokkaido in 2012. Of 81 candidates for a confirmation test because of positive (n = 77) or equivocal (n = 4) results on screening, 63 (78%) underwent the confirmation test and, finally, 34 (0.1%) and 33 563 (99.8%) women were judged to be HTLV‐1 carriers and non‐carriers, respectively. It was concluded that the prevalence rate of HTLV‐1 carriers was low, one per 1000 pregnant women in Hokkaido. Approximately 40 infants are born yearly to mothers infected with HTLV‐1 in Hokkaido.     

HIV-2 antibody testing of blood donors with doubtful immunoblot results for HIV-1

Antibodies against human immunodeficiency virus type-1 (HIV-1) in samples from blood donors are commonly detected by various enzyme-linked immunosorbent assays (ELISA) and by confirmatory tests, e.g., "Western blot" or immunofluorescence tests. Immunoblot reactivity, which is directed only towards the HIV-1 core proteins p 18, p 24 and p 55, may represent false-positive reactions. Out of 125,000 blood donations, 140 were repeatably HIV-1 antibody reactive by ELISA; of these, 20 were doubtful positive sera with isolated p 18 and/or p 24 bands in the HIV-1 confirmatory assay. Antibodies to HIV-2 are known to cross-react with these HIV-1 core proteins. We therefore assayed the 20 sera by immunofluorescence and immunoblotting for the presence of antibodies to HIV-2. None of these doubtful HIV-1 antibody positive blood donor sera was found to have antibodies to HIV-2.     

闽南地区TT病毒的变异及经输血传播的初步证据

TT virus(TTV)DNA was tested by nested-PCR from sera of hepatitis patients and volunteer blood donors in Minnan area. The amplified segment was a 189 base pair region in TTV ORF2. A total of six sequences were obtained from three non-A to G hepatits patients and two from volunteer blood donors. The sequences were found to be with 82.9% to 99.3% homology to TTV Japanese strain and Chinese strain. The divergence of sequence in these six segments varied from 0.7% to 17.1%, which indicated that the TTV had been existing for a long time in this area. In the serum of a non-A to G hepatitis patient who was negative for TTV DNA in the 14th day of disease course turned to be positive in the 30th day, two TTV sequences were obtained which showed 92.1% nucleotide homology. It indicated that different TTV strains can co exist in the same person. This patient's blood had been transfused ten times between the collection of his TTV negative sample and his positive serum sample. Seven of the blood donors were traced and sampled for sera, of which three were positive for TTV. For all 161 patients tested, the history of exposure to blood products was associated with an increased risk of TTV infection(relative risk, 3.0; 95% confidence intervals, 1.89～4.81).     

In vitro evaluation and study of the survival of erythrocytes preserved in a saline-adenine-glucose-mannitol medium for 35 days

The saline-adenine-glucose-mannitol (SAGM) solution for resuspension of red cells was evaluated on 30 blood units tested over 42 days and compared to 5 red cell concentrates collected on the conventional CPD medium. Total and extra-cellular hemoglobin, potassium, pH, ATP and DPG concentrations, osmotic fragility, schizocyte formation, and red cell antigenicity were studied through the storage period. Chromium survival studies of autologous donated red cells were performed in 10 donors. Red cell concentrates resuspended in SAGM solution showed at the 35th day of conservation at 4 degrees C, a mean storage hemolysis of only 0.66%, an ATP concentration of 67% of the initial value, a schizocyte proportion of less than 1.5%, a mean 24 hour posttransfusion viability of 88.33% and a mean red cell T 1/2 survival of 25 days 10 hours. No alteration of common blood group antigens could be found after storage of red cells for 42 days.     

中国HTLV-Ⅰ env基因的克隆及Ⅰ＋Ⅱ型嵌合基因的原核表达与抗原活性检测

为尽快研制出国产HTLV抗体诊断试剂,首先从福建HTLV流行区1名HTLV感染者外周血细胞中克隆出HTLV-Ⅰ的全长膜基因（env）,继而结合文献报道、PSA1软件的新疏水性分析和EPI软件的B细胞表位分析数据,选择了gp46中段开始延伸至gp21N端212个氨基酸（aa185-aa396)的基因,并在3‘端通过（GlySer)2与人工合成的HTLV-Ⅱ型的型特异性表位区基因嵌合,插入原核表达载体pRSET,在E.coli中得到了高效表达目的蛋白产量约占菌体总蛋白的30％。通过Triton-X100洗涤,低湿度尿素逐步变性处理,8mol/L尿素溶解后纯度在75％左右,经电泳洗脱纯化,最终纯度可达95%短期,纯蛋白得率约为40％。经Western blottiong检测,该蛋白对4份HTLV-Ⅰ型和2份HTLV-Ⅱ型均有较强反应,而对4份阴性,血清无反应,从而可能用于研究HTLV抗体诊断试剂盒。     

Blood transfusion and acquired immunodeficiency syndrome (AIDS)

This report was presented at the June 1983 meeting of the Blood Transfusion National Consultative Commission at the French Ministry of Health. Clinical and epidemiological data on AIDS as well as problems raised by the lack of specific tests for screening of blood donors were briefly summarized. Out of 49 AIDS patients recorded in France up to April 1983, only one had a history of previous blood transfusion given in Haiti, 4 years before the clinical onset of the disease. Blood donors, all Haitians, had no sign and symptom of AIDS. Retrospective review of 2 300 hemophiliacs followed up in France until April 1983 disclosed no AIDS. However, in 6 patients, the following features, more or less associated, were found to be present: thrombocytopenia, neutropenia, micropolyadenopathy, splenomegaly, hypergammaglobulinemia and low OKT4/OKT8 ratio. No clear correlation could be found between these abnormalities and the origin, commercial or national, of the coagulation factor concentrates used for the treatment. Three main recommendations were proposed: -- information of blood donors and experimental evaluation of some non specific screening tests, in the at risk donor population. -- more cautious use of coagulation factor concentrates -- reduction of importations aiming at complete national self sufficiency concerning factor VIII concentrates.     

HIV-specific antibody among voluntary blood donors in Lower Saxony (FRG)

Anti-HIV test results of the Red Cross Blood Transfusion Service of Lower Saxony from 1 June 1985 to 31 July 1986 inclusive were analysed retrospectively. Nine out of 70,936 donors who had not donated blood before 1 June 1985 (first-time donors) and 9 out of 261,231 donors who had donated blood before this date (repeating donors) were found anti-HIV confirmed positive at the time of the first blood donation during the study period. The prevalence of HIV antibody in first-time donors was significantly higher than in repeating donors (p less than 0.01). It was concluded that some members of risk groups used blood donation to obtain an anti-HIV test result. One out of 30,300 blood donations was confirmed anti-HIV positive. The results of this study justify the transfusion of blood donations that are reactive only in the initial ELISA test.     

No evidence for an association between glyoxalase 1 and haptoglobin in the white population of Victoria, Australia

No association between the glyoxalase 1 (GLO1) and haptoglobin (HP) systems was found in a sample of 1,270 white blood donors in the State of Victoria, Australia. This finding is in contrast to previous data for blood donors in Newfoundland, Canada, a population also of Anglo-Irish descent. However, the differences between the joint phenotypic distributions of GLO and HP in the 2 data sets were statistically insignificant.     

Inverse relationship between constitutive gamma interferon production and human T-cell lymphoma/leukemia virus expression in cultured T lymphocytes.

Particular interest in human T lymphocyte lymphoma/leukemia virus (HTLV) derives from the close association of HTLV with several types of human mature T lymphocyte malignancies and the strong possibility that HTLV is the causative agent of this group of leukemias and lymphomas. This is the first report to show that HTLV expression in T lymphocytes cultured in vitro is inversely proportional to constitutive gamma interferon production. Of 16 fresh T lymphocyte cultures established from patients with mature T lymphocyte neoplasias, 3 were grown continuously for over 3 years and 13 were grown for 2 to 8 months in culture. Of the 16 cultures, 9 were HTLVp19 positive and interferon negative, whereas the remaining 7 were HTLVp19 negative or weakly positive and also interferon positive (12 to 105 U/ml). The prototype HTLV-positive T-cell line (HUT102) was examined over a long-term culture and after selective cell cloning for high virus yield. Results indicate that early-passage, low-HTLV-producing HUT102 cells constitutively produced significant levels of gamma-immune interferon. In late-passage and cloned HUT102 cells, an increase in HTLV production was concordant with a decrease in constitutive interferon production and the loss of mature T lymphocyte antigens. Transformation of human umbilical cord blood lymphocytes by HTLV was possible only after cocultivation with the non-interferon, high virus-producing, cloned HUT102 T lymphocytes. The inverse relationship between interferon and HTLV production was also observed when normal human umbilical cord blood and adult T lymphocytes were transformed by HTLV and maintained in culture.     

Infectious disease screening of blood specimens collected post-mortem provides comparable results to pre-mortem specimens

Serology assays for standard screening are optimised for use with sera collected from living adults and children. Because of potential changes in the vascular compartments after death, methods used for screening sera from cadaveric organ donors need to be validated before testing these specimens. Serum was separated from blood collected from cadaveric donors within 24?h of death and biochemical parameters measured to detect dilution of protein and haemolysis. In order to demonstrate if any inhibitors that might interfere with the assays were present, pre and post-mortem specimens were spiked with aliquots of human immunodeficiency virus (HIV), hepatitis C virus (HCV), hepatitis B virus (HBV), human T-cell Lymphotropic Virus (HTLV) and T. pallidum-positive sera. Comparison of serum from living subjects with serum obtained post-mortem showed that while the concentration of total protein decreased, concentrations of albumin, immunoglobulin G (IgG) and immunoglobulin M (IgM) remained unchanged. The degree of haemolysis, as measured by free haemoglobin, was within the limits accepted for the Architect analyser. Spiking of pre- and post-mortem specimens with aliquots of HIV, HCV, HBV, HTLV and T. pallidum-positive sera showed no statistical difference in the signal between pre-mortem and post-mortem results when tested on the Abbott Architect analyser. Positive results were obtained in each of a further nine subjects who had tested positive for HIV (n?=?1), HCV (n?=?8), HBV (n?=?1) on pre-mortem serological testing. These findings suggest that the sensitivity of the Abbott Architect serological screening tests is not significantly affected in specimens collected within 24?h of the cessation of life.     

Promoter methylation of p16 and EDNRB gene in leukemia patients in Taiwan

Both epigenetic and genetic alternations are involved in cancer formation. In this study, we have identified the methylation frequency of p16 and endothelin receptor type B (EDNRB) of 26 leukemia patients and 8 randomly selected normal blood donors in Taiwan. Promoter methylation of p16 was detected in 85% of acute lymphocytic leukemia (ALL), 83% in acute myeloid leukemia (AML) whereas no methylation was detected in chronic myeloid leukemia (CML) in blast crisis. Hypermethylation of EDNRB was observed in 92% of ALL, 75% AML and 100% in CML in blast crisis. No aberrant methylation of p16 and EDNRB was found in 8 normal blood donors. Taken together, aberrant methylation of p16 and EDNRB was highly prevalent in leukemia patients in Taiwan.