Prevalence of antibodies to HTLV in antenatal clinic attenders in south east London

The prevalence of antibodies to HTLV in women attending a south east London antenatal clinic between October 1990 and July 1992 was determined using sera referred for rountine rubella antibody testing. Samples were screened for HTLV antibody using a modified Fujirebio gel particle agglutination test and reactive sera confirmed by ELISA (Abbott Laboratories, North Chicago, IL) and two commercial Western blots (Cambridge Biotech Inc., Rockville, MD, and Diagnostic Biotechnology, Genelab Diagnostics, Louvaine, Belgium). This strategy confirmed the presence of HTLV-1 antibodies in 12 out of 6,289 sera (0.19 percent, 95 percent confidence limits 0.083 percent to 0.30 percent) and HTLV-2 antibodies in 2 (0.03 percent) sera. Specimens from 8 to 821 (0.97 percent, 95 percent confidence limits 0.42 percent to 1.9 percent). Afro-Caribbean women, three of 1,136 (0.26 percent, 95 percent confidence limits 0.055 percent to 0.78 percent). African women, and one of 3,049 (0.033 percent, 95 percent confidence limits 0.006 percent to 0.18 percent). Caucasian women were positive for HTLV-1 antibodies. Sera from Afro-Caribbean women born in the Caribbean were 7.6 times more likely to be HTLV-1 antibody positive than sera from Afro-Caribbean women born in the UK (P = 0.012). Selective testing of Afro-Caribbean and African antenatal clinic attenders, in this setting, would have identified 11 of the 12 HTLV-1 infections at an estimated cost of prevention of HTLV-1 associated disease of 100,000 pounds per case which is considerably less than the 1.3 million pounds which has been estimated to prevent a case by universal screening of UK blood donors.(AU)

De prevalentie van humaan T-Lymfotroop virus type 1 en 2 bij bloeddonors en patienten met seksueel overdraagbare aandoeningen in Suriname / The prevalence of human T-Lymphotropic virus types 1 and 2 in blood donors and patients with sexually transmitted diseases in Suriname

OBJECTIVE; To determine the prevalence of HTLV-1 and HTLV-2 infection in the population of Suriname in order to enhance the safety of blood transfusion in Suriname. DESIGN; Descriptive. SETTING; Academic Hospital, Paramaribo, Suriname. METHOD: Blood was examined of the 777 regular donors(constituting 97 procent of the total pool) who donated blood between 1 February and 1 June 1995 at the Blood Transfusion Centre of the Suriname Red Cross in Paramaribo, and also of the 140 patients with a sexually transmitted disease (STD) seen during the same period at the Dermatological centre of the Ministry of Health. All sera were sreened with particle agglutination. Sera which were not negative were subsequently tested with a western blot method which distinguishes between HTLV-1 and HTLV-2. RESUTLS. Three sera (0.4 percent) of the blood donors and 2(1.4 procent) of the STD patents were positive for HTLV-1(difference not significant). Nobody was found to be HTLV-2 positive. CONCLUSION; The HTLV-1 prevalence in the Suriname blood donors is similar to that of blood donors and general population of many regions in Brazil, but substantially lower than in several other regions in the Caribbean. Since examination of all donated blood is not a realistic option in Suriname it is recommended that all new regular blood donors should be tested for HTLV antibodies(AU)

Viral specific humoral immune responses following transfusion-related transmission of human T cell lymphotropic virus type-I infection

The immunoglobulin (Ig) isotypes of antibodies to specific proteins of the human T cell lymphotropic virus type I (HTLV-I) were determined by Western blot analysis of serial specimens from six individuals who experienced HTLV-I seroconversion following blood transfusion; five remained asymptomatic carriers, while one developed HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP) 32 weeks posttransfusion. Analysis of Ig isotypes demonstrated that while IgM was the most frequent early response to gag (p19, p24) and env (r21e) proteins within the first 3 months following transfusion, IgG and IgA responses could also be detected within this period. HTLV-I-specific antibody responses plateaued in all Ig isotypes, including IgM, wtihin the next 4- to 6-months period following transfusion and pesisted through the entire study period (> 4 years). Comparison of antibody profiles in Ig isotypes and IgG1 and IgG3 subclass among asymptomatic carriers and one individual who developed HAM/TSP demonstrated no evidence of isotypic prominence or IgG subclass restriction in either group. These results indicate the appearance of HTLV-I-specific IgM that persists even after the primary infection and suggest that such responses does not appear to provide an early marker of seroconversion. Further, we found no evidence of isotypic prominence or restriction of the antibody response in recipients who remained asymptomatic compared to one who developed HAM/TS.(AU)

Segregation of human T cell lymphotropic virus type I and II infections by antibody reactivity to unique viral epitopes

A recombinant protein of the human T cell lymphotropic virus type I (HTLV-I) gp46 outer membrane envelope, MTA-4 (residues 129-203), reacted by Western blot with sera from HTLV-I-infected individuals from the United States and Jamaica but not with 24 (10 percent) of 242 Japanese sera. A related gp46 recombinant protein, MTA-1 (residues 162-209), reacted with all 58 sera from HTLV-I-infected US and Jamaican individuals and 238 of 242 sera from infected Japanese (combined sensitivity of 99 percent). Neither recombinant showed reactivity to sera from HTLV-II-infected individuals or uninfected controls. The reactivity of recombinant proteins containing the region of HTLV-II gp46 analogous to MTA-1 was also evaluated by Western blot: GH2-K15 (residues 157-205) and GH2-K55 (residues 162-205) reacted with 88 (98 percent) and 89 (99 percent), respectively, of 90 sera from HTLV-II-infected individuals but not with sera from HTLV-I-infected individuals or uninfected controls. These recombinant proteins should permit the development of assays to unambiguously confirm and differentiate HTLV-I and HTLV-II infections. (AU)

High human T-cell lymphotropic virus type I proviral DNA load with polyclonal integration in peripheral blood mononuclear cells of French West Indian, Guianese, and African patients with tropical spastic paraparesis

Human T-cell lymphotropic virus type I (HTLV-I) proviral integration status was examined by Southern blot analysis in peripheral blood mononuclear cell (PBMC) DNA from patients presenting a tropical spastic paraparesis (TSP) and serological evidence of HTLV-I infection. Surface phenotype and morphological aspects of PBMC were also studied. A polyclonal HTLV-I proviral integration was found in the PBMC of the 10 patients studied irrespective of their geographical origin (French West Indies, French Guiana, and Africa), the duration of their clincal illness, or the HTLV-I antibody titer. Furthermore, by dilution experiments and hypothesizing that only one copy of HTLV-I proviral DNA is present in one call, we estimated that this HTLV-I integration is present in 3 percent to 15 percent of their PBMC. All 10 TSP/HTLV-I patients studied had an average of 10 percent of thier lymphocytes abnormal, presening either a misshapen nucleus or an adult T-cell leukemia/lymphoma(ATL)-like feature. Moreover, an elevated CD4/CD8 ratio associated with the presence of activated T cells with a high level of DR expression was observed in most patients. The significant frequency of viral-positive PBMC and the important load of HTLV-I proviral DNA that we observed in TSP/HTLV-I patients might play an important role in the pathogenesis of this recently identified clinico-virological entity. (AU)