Involvement of human intracisternal A-type retroviral particles in autoimmunity.

Prior studies have linked retroviruses to various arthropathies and autoimmune diseases. Sjögren's syndrome (SS), a systemic autoimmune disease, is characterized by aggressive infiltration of lymphocytes into the salivary and lacrimal glands, resulting in destruction of the glands and dry mouth and eyes (sicca syndrome). The infiltrating lymphocytes in SS may become overtly malignant, and thus, the incidence of lymphoma is greatly increased in SS patients. A human intracisternal A-type retroviral particle type I (HIAP-I) has been isolated from persons with SS. HIAP-I shares a limited number of antigenic epitopes with human immunodeficiency virus (HIV), but is distinguishable from HIV by morphological, physical, and biochemical criteria. A substantial majority of patients with SS or systemic lupus erythematosus (SLE) have serum antibodies to the proteins of this human retrovirus. Fewer than 3% of the normal blood donor population have antibodies to any HIAP-associated proteins. A second type of a human intracisternal A-type retrovirus, HIAP-II, was detected in a subset of patients with idiopathic CD4 lymphocytopenia (ICL), an AIDS-like immunodeficiency disease. Most HIAP-II positive ICL patients were also antinuclear antibody positive. Reviewed here are additional studies from several laboratories suggesting that HIAP or related viruses may be involved in SLE and other autoimmune conditions. Additionally, results of comprehensive surveys of autoimmune patients to determine seroreactivity to HIAP, and other human retroviruses, including HIV and human T-lymphotropic virus type I, are reported.

Evidence of HIV exposure and transient seroreactivity in archived HIV-negative severe hemophiliac sera.

BACKGROUND: Approximately 25% of hemophiliacs that were frequently exposed to blood clotting factor concentrates (CFCs) contaminated with human immunodeficiency virus (HIV) are presently HIV seronegative. In this study, we sought to determine if some of these individuals were at any time transiently HIV seropositive. In the early to mid-1980s the majority of severe hemophilia patients were exposed to CFCs contaminated with HIV. Although many of these hemophiliacs became HIV-positive, a small percentage did not become infected. To determine if some of these individuals successfully resisted viral infection, we attempted to document the presence of transient HIV reactive antibodies in archived plasma samples (1980-1992) from currently HIV-negative severe hemophiliacs who had a high probability of repeated exposure to HIV contaminated CFC. Archived plasma samples were retrospectively tested using an FDA approved HIV-1Ab HIV-1/HIV-2 (rDNA) enzyme immunoassay (EIA) and a HIV-1 Western blot assay (Wb), neither of which were commercially available until the late 1980s, which was after many of these samples had been drawn. RESULTS: We found that during the high risk years of exposure to HIV contaminated CFC (1980-1987), low levels of plasma antibodies reactive with HIV proteins were detectable in 87% (13/15) of the haemophiliacs tested. None of these individuals are presently positive for HIV proviral DNA as assessed by polymerase chain reaction (PCR). CONCLUSION: Our data suggest that some severe hemophiliacs with heavy exposure to infectious HIV contaminated CFC had only transient low-level humoral immune responses reactive with HIV antigens yet remained HIV-negative and apparently uninfected. Our data supports the possibility of HIV exposure without sustained infection and the existence of HIV-natural resistance in some individuals.

Oral health status of 12 year old children in St. Lucia and its association with oral health knowledge, attitudes and practices

OBJECTIVE: This study was carried out in St. Lucia, one of the islands of the eastern Caribbean. The island's population of 150,000 persons is relatively young, with 45 percent under the age of twenty years. The study sought to determine the oral health status of 12-year-old children and its association with oral health knowledge, attitudes and practices. METHODS: A cross-sectional survey was undertaken. Four schools (two rural and two urban) were randomly selected from 14 schools in the north of the island. Simple random sampling was used to select 97 students aged 12 years (15 percent of the school population). Trained dental personnel performed a dental examination and recorded the students' decayed, missing or filled teeth (DMFT) status. The principal investigator (SA) administered a structured questionnaire as well as performed the oral examinations. World Health Organization (WHO) guidelines for DMFT surveys were adhered to. The data were collected in July 2000 and analysed using SPSS, version 9. RESULTS: The DMFT level of the students was 2.0, which by WHO standards is low. This compares quite favourably with a 1997 study when the DMFT level identified in an island-wide study was 6.0. It should be noted, however, that 65.3 percent of children had 1 to 7 decayed teeth, 8.2 percent had 1 to 4 missing teeth, with only 9.2 percent have 1 to 2 filled teeth, indicating the need for access to routine dental examination and treatment. Knowledge and practice levels were generally good, which may explain the low DMFT level. CONCLUSION: Dental health education is currently integrated into the school curriculum and is provided by teachers. This would seem to be an effective avenue for dental health education. However, it needs to be supported by increased access to rutine examination and treatment by dental health personnel. Proper planning or oral health education programmes that include oral health education and behaviour modification, along with public health measures such as salt fluoridation, would contribute to further reducing the incidence of oral diseases. (Au)

Human T-lymphotropic virus type I (HTLV-I) seroprevalence in Jamaica: I. demographic determinants

During 1985 and 1986, the authors measured antibodies to human T-lymphotropic virus type I (HTLV-I) in a cohort of 13,260 Jamaicans from all parts of the island who applied for food-handling licenses. HTLV-I seroprevalence was strongly age and sex dependent, rising from 1.7 percent (10-19 years) to 9.1 percent (o70 years) in men and from 1.9 percent (10-19 years) to 17.4 percent (o70 years) in women. In a logistic regression analysis, women were more likely to be seropositive than were men, and farmers, laborers, and the unemployed were more likely to be HTLV-I seropositive than were those reporting student or professional occupations. In men, African ethnicity was associated with HTLV-I seropositivity in the univariate analyssis but was not a risk factor after adjustment for age and sex. There was a trend toward higher age-stratified HTLV-I seroprevalence among younger women who reported more pregnancies, but older multigravidas had lower rates of HTLV-I seropositivity. Persons born outside Jamaica had significantly lower seroprevalence than did those born in Jamaica, but they were of slightly different ethnic and occupational compositions than those born in Jamaica. (AU)

Human T lymphotropic virus type I antibody patterns: evidence of difference by age and risk group

Detection of human T lymphotropic virus type I (HTLV-I) antibody was assessed on 368 sera from subjects with different clinical features and from different parts of the world. Enzyme-linked immunosorbent assay (ELISA) and radioimmunoassay for purified p24 antibodies (p24-RIA) used as screening tests agreed in 88.7 percent of the sera. The results from 247 selected sera were compared with western blot (WB). WB was reactive in sera five to 25 times more dilute than the last positive ELISA or p24-RIA, but different WB batches varied in sensitivity. ELISA was more sensitive than p24-RIA, and p24-RIA was more specific than ELISA. Indeterminate WB interpretations were common (25.5 percent). Most seropositive intravenous drug abusers had unusually strong p24 bands by WB. Among healthy individuals, positive WB reactivity increased with age, whereas indeterminate reactivity declined (P=.034). Thus more sensitive and -specific HTLV-I antibody tests are needed. (AU)