Search PubMed⌕ Search

Biomedical subjects

D Gallo

Publications and source records attributed to D Gallo.

At least 37 records · Page 2Linked to original sources
PubMed1996

Comparison of four enzyme immunoassays for detection of human T-cell lymphotropic virus type 2 antibodies.

Four licensed enzyme immunoassay (EIA) kits for the measurement of antibody to human T-cell lymphotropic virus (HTLV) type 1, one from Organon Teknika Corp. (OTC), one from Cambridge Biotech Corp. (CBC), and two from Abbott Laboratories (the 1993 modification [Abb 93] and the 2.0 version licensed in 1995 [Abb 95]), were evaluated for sensitivity and specificity in the detection of HTLV type 2 antibody, and the results were compared with those previously obtained with earlier kit versions. The CBC, Abb 95, Abb 93, and OTC kits had sensitivities of 99.7, 97.6, 96.8, and 96.2%, respectively, compared with sensitivities of 89.1 and 60% for the Abbott and CBC (previously DuPont) kits, respectively, licensed in 1988. Thus, the abilities of commercial kits to detect HTLV antibody have improved. The relative specificities of the CBC, Abb 95, Abb 93, and OTC kits with negative blood donor specimens that had been reactive with the 1988 CBC EIA kit were 92.9, 64.5, 78.8, and 62.6%, respectively. Compared with those of the 1988 versions, the specificity of the Abbott EIA has decreased and the specificity of the CBC kit has been significantly improved.

Blood Donors↗
PubMed1995

Formation of nuclear bodies in hepatocytes of estrogen-treated roosters.

As a model for cellular growth and stimulation without accompanying proliferation, we have examined the induction and formation of nuclear bodies (NBs) in hepatocytes of estrogen-treated roosters. Four-week-old roosters were injected with a single intramuscular dose of estradiol and then killed at time points of 8 h, 48 h, and 4 wk post-injection. For immunofluorescence analyses, livers were excised and isolated hepatocyte nuclei were fixed and then labeled with antibody to the coiled body-specific protein, p80-coilin. In control animals (no estradiol) or in animals 8 h post-injection, each hepatocyte nucleus contained an average of 1.0 coiled body (CB), which appeared randomly distributed in the nucleoplasm. At 48 h post-injection, there were an average of 2.7 CBs/nucleus and many of these appeared to be in contact with the nucleolus. Pairs of CBs were also observed. By 4 wk post-injection an average of 1.5 CBs/nucleus were detected, with no apparent relationship to the nucleolus observed. By serial-section electron microscopy of intact livers, two different types of round NBs were observed, sometimes in close proximity to each other and to the expanded interchromatin granule region in maximally stimulated cells. One type of NB was a classical CB that averaged 0.35 microns in diameter and the other NB type was ring shaped, averaged 0.25 microns in diameter, was composed of a fibrous shell surrounding a hollow interior, and appeared as a simple NB when sectioned tangentially through its outer shell. Immunoelectron microscopy revealed that CBs were the only class of NBs that contained p80-coilin. From these data, we conclude that CBs proliferate in response to estrogen stimulation, possibly arising from the nucleolar surface and then increasing in number by replicative division.

Animals↗
PubMed1994

Sensitivities of radioimmunoprecipitation assay and PCR for detection of human T-lymphotropic type II infection.

Five hundred forty-eight uncoagulated blood specimens from intravenous drug users infected with human T-lymphotropic virus type II (HTLV-II) were used to evaluate the sensitivities of the radioimmunoprecipitation assay (RIPA) and PCR for detecting HTLV-II-infected people. The sensitivities of both RIPA and PCR were found to be dependent on the HTLV-II antibody titer, as determined by the immunofluorescence assay. Neither of these recommended confirmatory methods was as sensitive for detecting weakly reactive HTLV-II specimens as the immunofluorescence assay, Western blotting (immunoblotting), or a modified licensed enzyme immunoassay. Use of RIPA and PCR to determine the reliabilities of other tests may sometimes give erroneous results.

DNA, Viral↗
PubMed1994

Evaluation of two commercial human T-cell lymphotropic virus western blot (immunoblot) kits with problem specimens.

We evaluated two commercial human T-cell lymphotropic virus (HTLV) Western blot (WB; immunoblot) kits, Cambridge Biotech Corp. (CBC) and Diagnostic Biotechnology Ltd. (DBL). Both methods employ HTLV type I (HTLV-I) viral lysate and rgp21. The DBL WB kit also distinguishes between HTLV-I and HTLV-II antibodies, using an HTLV-I-specific and an HTLV-II-specific recombinant. Fifty weakly reactive HTLV-II-positive plasma specimens which were falsely negative with the Abbott enzyme immunoassay (EIA) and 50 Ortho EIA false-positive samples were selected to determine sensitivity and specificity. The sensitivities of the CBC and the DBL WB kits were 90 and 68%, respectively. All positive samples reacted with rgp21 in both kits, but some did not display core bands. Five samples were typed as HTLV-I and four were typed as dual infection by the DBL WB kit. The specificities of the CBC and DBL kits were 48 and 70%, respectively. The most prevalent WB reaction with the negative samples was with the core protein, p19, followed by p24 and p28 for CBC and rgp21 and p28 for DBL. DBL had two false-positive interpretations, and CBC had none, rgp21 was the most sensitive antigen in both kits for the weakly reactive HTLV-II samples. If all samples not reacting with this protein were interpreted as WB negative, regardless of other bands, the specificity would improve to 90% for CBC and 86% for DBL.

Blotting, Western↗
PubMed1993

First description of endemic HTLV-II infection among Venezuelan Amerindians.

We describe for the first time the presence of human T lymphotropic virus type II (HTLV-II) infection in Venezuela, among the Pume Amerindians living in the southern plains of the country. Antibodies to HTLV-II antigens were assessed by enzyme immunoassays (Elisa), Western blot, radioimmuno-precipitation, and immunofluorescence; titration studies against HTLV-I- and HTLV-II-infected cell lines were very useful in the differentiation of HTLV-I and HTLV-II antibodies. The HTLV-II general prevalence was 5%; however, there is a striking difference in prevalence between the truly isolated villages (0%) when compared to those living along the riverside and thus in contact with outsiders (9%). Preliminary evidence suggests sexual contact as the main source of transmission. These findings might suggest that HTLV-II in Venezuela originated through contact with outsiders rather than ancient infection related to the origins of the Pume.

Adolescent↗
PubMed1993

No evidence of perinatal transmission of HTLV-II.

Two hundred twenty-eight plasma specimens collected over a 4-year period from 185 children aged 4 days to 10 years at risk for human immunodeficiency virus (HIV) infection were tested for antibody to human T-cell lymphotropic virus type II (HTLV-II) to determine perinatal transmission of this agent. One hundred three of the specimens were from 68 children whose mothers were intravenous drug users (IVDU). None of the children in the study were breast fed. No HTLV antibody was detected in any of the samples from children of non-IVDU mothers. However, HTLV-II antibody was found in samples from 15 of 38 infants < 6 months old born to IVDU mothers. Later specimens taken at 8-16 months from six of these children were negative, suggesting passive maternal antibody, not infant infection. The 62 samples from 30 children 6 months to 7 years old from IVDU mothers were negative for HTLV antibody. The lack of HTLV antibody in the older children indicates that no vertical transmission had occurred. Based on the prevalence rate of maternal HTLV-II antibody found in the children < 6 months old, an HTLV-II infection rate of approximately 36% was projected for the IVDU mothers in the study.

Child↗
PubMed1992

Detection of antibodies to human immunodeficiency virus type 2 (HIV-2) in blood donor sera using United States assay methods for anti-HIV type 1.

Twelve serum samples from French blood donors that were uniformly reactive in tests for antibody to human immunodeficiency virus type 2 (anti-HIV-2) also were reactive in 92 to 100 percent of tests with three anti-HIV type 1 (anti-HIV-1) enzyme-linked immunoassays currently in widespread use for donor screening in the United States. Supplemental tests for anti-HIV-1 on these anti-HIV-2-reactive samples differed in their responses. All samples reacted in a licensed anti-HIV-1 Western blot, but there was an atypical band near the p41 position, which could be a clue to the fact that this result was a cross-reaction with anti-HIV-2. A recombinant immunoblot gave an indeterminate result for anti-HIV-1 in all 12 samples. A local immunofluorescence assay for anti-HIV-1 reacted with 92 percent of the samples, but a commercial one detected only 58 percent.

Antibodies, Viral↗
PubMed1992

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%) 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%). 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%) and 89 (99%), 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.

Amino Acid Sequence↗
PubMed1992

Reliability of polymerase chain reaction in the detection of human immunodeficiency virus infection in children.

During a 3-year period we followed 128 human immunodeficiency virus (HIV) antibody-positive children ages 6 days to 11 years clinically and with an HIV diagnostic panel consisting of antibody (by enzyme-linked immunosorbent assay and confirmed by indirect fluorescence assay or Western blot), p24 antigen detection, HIV isolation from peripheral blood culture and molecular detection of HIV nucleic acids by polymerase chain reaction (PCR). The PCR procedure included 30 cycles of amplification using two separate gag primer pairs (SK38/39 and SK101/145), followed by detection with probes to areas amplified (SK19 and SK102). Results of PCR were available within 48 hours and were sensitive (97%) and specific (100%). PCR should be obtained on all children exposed perinatally, and aggressive management should be undertaken for those found to be positive.

AIDS Serodiagnosis↗
PubMed1992

Comparison of six commercial human T-cell lymphotropic virus type I (HTLV-I) enzyme immunoassay kits for detection of antibody to HTLV-I and -II.

Three licensed and three research human T-cell lymphotropic virus type I (HTLV-I) enzyme immunoassay (EIA) kits were evaluated with a panel of 213 serum or plasma samples which were previously tested by the indirect immunofluorescence method for HTLV-I and -II antibodies. The three research kits were found to be more sensitive and specific than the three licensed kits.

Evaluation Studies as Topic↗
PubMed1992

Comparison of indirect immunofluorescence and membrane fluorescence assays for the differentiation of antibodies to human immunodeficiency virus types 1 and 2.

Serum samples from 20 human immunodeficiency virus type 1 (HIV-1)- and 30 HIV-2-infected and 7 dually infected individuals were reacted by using the indirect immunofluorescence assay (IFA) and membrane fluorescence assay in order to determine whether these methods were useful for typing HIV-1 and HIV-2 antibodies. Although 41 of 50 (82%) of the HIV-1- and HIV-2-positive specimens cross-reacted to some extent with the heterologous antigen in the IFA, the antigen with the higher titer correlated completely with the infecting type. The IFA could not distinguish single from dual infections, however. In contrast, only 4 of the 50 (8%) serum samples cross-reacted in the membrane fluorescence test. All seven of the specimens from patients with mixed infections reacted with both antigens. The membrane fluorescence test appears to be reliable for serodifferentiation of HIV-1 and HIV-2 infections and may be useful for laboratories with low-volume typing requirements.

Antibody Specificity↗
PubMed1992

Prevalence of human T cell lymphotropic virus types 1 and 2 (HTLV-1/2) in selected Tijuana subpopulations.

To assess the prevalence of human T cell lymphotropic virus type 1 and 2 (HTLV-1/2) infections among potentially high-risk populations in the city of Tijuana, Mexico, the prevalence of specific antibodies was determined and information on risk behaviors was obtained between June and October 1988. The study involved 631 presumably healthy individuals, randomly selected from a study population recruited sequentially from prisoners, prostitutes, and injecting drug users (IDUs), and randomly from homosexual and bisexual men. The presence of HTLV-1/2 antibodies was determined by enzyme immunoassay and an immunofluorescence method, and positive reactions were confirmed by a radioimmunoprecipitation assay and Western blot. The prevalence of HTLV-1/2 was 2% (2 of 105) among prostitutes, 7% (29 of 410) among prisoners, 1% (1 of 105) among homosexual/bisexual men, and 21% (22 of 106) among IDUs. To properly identify the specific HTLV type, a subsequent sample of 41 imprisoned IDUs were voluntarily and anonymously recruited in June 1990 and asked to donate 20 ml of whole blood. Twenty-two percent (9 of 41) were serologically positive for HTLV-1/2, and polymerase chain reaction analysis performed on peripheral blood mononuclear cells identified HTLV-2 as the specific virus prevalent in this group. Two individuals were positive for human immunodeficiency virus type 1 (HIV-1). One of these individuals was coinfected with HTLV-2.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗