scholarly journals Incidence of Human Immunodeficiency Virus Antibody in a Prenatal Population at a Community Hospital

1999 ◽  
Vol 6 (1) ◽  
pp. 140-141 ◽  
Author(s):  
Thomas S. Alexander ◽  
Joanne Lee ◽  
Belinda Yen-Lieberman
Keyword(s):  
Human Immunodeficiency Virus ◽  
Hiv Transmission ◽  
Community Hospital ◽  
Hiv Infections ◽  
Enzyme Linked Immunosorbent Assay ◽  
Hiv Screening ◽  
Virus Antibody ◽  
Immunodeficiency Virus ◽  
Positive Results ◽  
Hiv 1

ABSTRACT Prenatal human immunodeficiency virus (HIV) screening may reduce vertical HIV transmission. We screened 4,419 prenatal sera and found 38 repeatedly reactive specimens with an HIV-1–HIV-2 enzyme-linked immunosorbent assay. Western blot analysis confirmed four of these specimens as positive for HIV-1 antibodies. Screening detects previously unidentified HIV infections, but false-positive results may also occur.

scholarly journals Comparison of an Amplified Enzyme-Linked Immunosorbent Assay with Procedures Based on Molecular Biology for Assessing Human Immunodeficiency Virus Type 1 Viral Load

1998 ◽  
Vol 5 (4) ◽  
pp. 513-518 ◽  
Author(s):  
Pablo L. Goldschmidt ◽  
Andrée Devillechabrolle ◽  
Zaina Ait-Arkoub ◽  
Jean-Thierry Aubin
Keyword(s):  
Human Immunodeficiency Virus ◽  
Viral Load ◽  
Molecular Biology ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Enzyme Linked Immunosorbent Assay ◽  
Immunodeficiency Virus ◽  
Positive Results ◽  
Hiv 1

ABSTRACT The sensitivity of the enzyme-linked amplified sorbent test (ELAST) was compared with those of other classic enzyme-linked immunosorbent assays (ELISAs), with or without previous acidic immunocomplex dissociation (ICD), in a series of samples at different stages of human immunodeficiency virus type 1 (HIV-1) infection. The limit of viral detection of ELAST was assessed with fresh HIV-1 preparations quantified by reverse transcription-PCR and with the P24 antigen (Ag) Sanofi Pasteur Calibrator containing lyophilized virus. The P24 Ag detection capacity of ELAST was compared with that of NASBA in samples obtained from infected subjects with less than 250 CD4+ cells. The results of the present study show that ELAST was the most sensitive method for detecting P24 Ag compared to classic ELISA and ICD plus ELISA. ELAST was able to detect 0.5 pg of P24 Ag per ml in a whole virus preparation and the equivalent of 330 to 1,000 RNA copies/ml of HIV. The rate of detection of P24 Ag was always higher in subjects with low levels of anti-P24 antibodies. The number of positive results was dramatically enhanced (from 37% to 94% for subjects with <250 CD4+ cells) when the incubation period was prolonged from 1 to 16 h. In a third series of 84 samples (<250 CD4+ cells) tested in parallel, NASBA yielded 83% of the positive results and ELAST yielded 79%. Considering the high sensitivity, low cost, simplicity of equipment (only a plate reader), and possibility for full automation, ELAST appears to be a promising new tool for measuring viral load, especially in areas with few resources, in which the procedures based on molecular biology techniques may be difficult to install.

scholarly journals 1061. False Positive Human Immunodeficiency Virus Testing Due to Acute Hepatitis A Infection: A Case Series

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S559-S559
Author(s):  
Maria V Bandres ◽  
Daniel Mueller
Keyword(s):  
Human Immunodeficiency Virus ◽  
Acute Hepatitis ◽  
Hiv Testing ◽  
False Positive ◽  
Hepatitis A ◽  
Screening Tests ◽  
Hiv Screening ◽  
Immunodeficiency Virus ◽  
Acute Hepatitis A ◽  
Hiv 1

Abstract Background In our urban, underserved patient population, Human Immunodeficiency Virus (HIV) is hyper-endemic, and HIV screening is frequently performed. Although HIV screening tests have high specificity, false positives can occur. Numerous reasons for false positive testing have been cited, including vaccinations, autoimmune diseases, and viral infections. In 2019, Philadelphia experienced a large Hepatitis A outbreak, during which time false positive HIV screening tests were discovered. Our aim was to further describe these patients who had been diagnosed with acute Hepatitis A infection and in whom false positive HIV testing had occurred. Methods We conducted a retrospective chart review of adult patients admitted to our hospital between January 2017 and December 2019 who had a positive Hepatitis A Virus (HAV) IgM. Demographics, HIV tests, viral hepatitis tests, and liver tests were recorded. False positive HIV was defined as a positive HIV screen (p24 antigen and HIV-1 and 2 antibody combo), followed by a negative differentiation assay for HIV-1 and 2 antibodies, combined with a negative HIV PCR. Results A total of 156 unique patients were found to have acute HAV, with 138 cases identified in 2019. Of these, 3 patients had confirmed false positive HIV testing, and 1 patient had suspected false positive HIV testing (HIV-2 differentiation assay indeterminate, with very low local prevalence of HIV-2), for a false positive test rate of 2.6% (4/156). Ages ranged from 36-47 years, 3 were male, and 2 were persons who injected drugs (PWID). Three patients had prior negative HIV testing. Two patients had fevers during admission, but none of the four were febrile at the time of HIV test collection. Three patients had elevated transaminases, and two had abnormal coagulation testing. Coinfection with Hepatitis C was found in three patients. One patient had follow-up HIV testing performed, which was negative. Conclusion To our knowledge, this is the first report of false positive HIV testing related to acute HAV. Prevalence of false positives was low, but awareness can facilitate patient counseling. With low sample size, conclusions cannot be drawn about risk factors related to false positive testing. Disclosures All Authors: No reported disclosures

scholarly journals Structure-Function Analysis of the Epitope for 4E10, a Broadly Neutralizing Human Immunodeficiency Virus Type 1 Antibody

2006 ◽  
Vol 80 (4) ◽  
pp. 1680-1687 ◽  
Author(s):  
Florence M. Brunel ◽  
Michael B. Zwick ◽  
Rosa M. F. Cardoso ◽  
Josh D. Nelson ◽  
Ian A. Wilson ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Function Analysis ◽  
Enzyme Linked Immunosorbent Assay ◽  
Peptide Epitope ◽  
Immunodeficiency Virus ◽  
Hiv 1 ◽  
4E10 Antibody

ABSTRACT The human immunodeficiency virus type 1 (HIV-1) neutralizing antibody 4E10 binds to a linear, highly conserved epitope within the membrane-proximal external region of the HIV-1 envelope glycoprotein gp41. We have delineated the peptide epitope of the broadly neutralizing 4E10 antibody to gp41 residues 671 to 683, using peptides with different lengths encompassing the previously suggested core epitope (NWFDIT). Peptide binding to the 4E10 antibody was assessed by competition enzyme-linked immunosorbent assay, and the Kd values of selected peptides were determined using surface plasmon resonance. An Ala scan of the epitope indicated that several residues, W672, F673, and T676, are essential (>1,000-fold decrease in binding upon replacement with alanine) for 4E10 recognition. In addition, five other residues, N671, D674, I675, W680, and L679, make significant contributions to 4E10 binding. In general, the Ala scan results agree well with the recently reported crystal structure of 4E10 in complex with a 13-mer peptide and with our circular dichroism analyses. Neutralization competition assays confirmed that the peptide NWFDITNWLWYIKKKK-NH2 could effectively inhibit 4E10 neutralization. Finally, to limit the conformational flexibility of the peptides, helix-promoting 2-aminoisobutyric acid residues and helix-inducing tethers were incorporated. Several peptides have significantly improved affinity (>1,000-fold) over the starting peptide and, when used as immunogens, may be more likely to elicit 4E10-like neutralizing antibodies. Hence, this study represents the first stage toward iterative development of a vaccine based on the 4E10 epitope.

scholarly journals Immunoglobulin G3 from Polyclonal Human Immunodeficiency Virus (HIV) Immune Globulin Is More Potent than Other Subclasses in Neutralizing HIV Type 1

2001 ◽  
Vol 75 (14) ◽  
pp. 6558-6565 ◽  
Author(s):  
Orit Scharf ◽  
Hana Golding ◽  
Lisa R. King ◽  
Nancy Eller ◽  
Doug Frazier ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Immune Globulin ◽  
High Titer ◽  
Passive Immunization ◽  
Hinge Region ◽  
Enzyme Linked Immunosorbent Assay ◽  
Fab Fragments ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Passive antibody prophylaxis against human immunodeficiency virus type 1 (HIV-1) has been accomplished in primates, suggesting that this strategy may prove useful in humans. While antibody specificity is crucial for neutralization, other antibody characteristics, such as subclass, have not been explored. Our objective was to compare the efficiencies of immunoglobulin G (IgG) subclasses from polyclonal human HIV immune globulin (HIVIG) in the neutralization of HIV-1 strains differing in coreceptor tropism. IgG1, IgG2, and IgG3 were enriched from HIVIG by using protein A-Sepharose. All three subclasses bound major HIV-1 proteins, as shown by Western blot assay and enzyme-linked immunosorbent assay. In HIV-1 fusion assays using X4, R5, or X4R5 envelope-expressing effector cells, IgG3 more efficiently blocked fusion. In neutralization assays with cell-free viruses using X4 (LAI, IIIB), R5 (BaL), and X4R5 (DH123), a similar hierarchy of neutralization was found: IgG3 > IgG1 > IgG2. IgG3 has a longer, more flexible hinge region than the other subclasses. To test whether this is important, IgG1 and IgG3 were digested with pepsin to generate F(ab′)2 fragments or with papain to generate Fab fragments. IgG3 F(ab′)2 fragments were still more efficient in neutralization than F(ab′)2 of IgG1. However, Fab fragments of IgG3 and IgG1 demonstrated equivalent neutralization capacities and the IgG3 advantage was lost. These results suggest that the IgG3 hinge region confers enhanced HIV-neutralizing ability. Enrichment and stabilization of IgG3 may therefore lead to improved HIVIG preparations. The results of this study have implications for the improvement of passive immunization with polyclonal or monoclonal antibodies and suggest that HIV-1 vaccines which induce high-titer IgG3 responses could be advantageous.

Late diagnosis of human immunodeficiency virus infections in high-risk groups in Karachi, Pakistan

2018 ◽  
Vol 29 (14) ◽  
pp. 1400-1406
Author(s):  
Zahra Hasan ◽  
Sharaf Shah ◽  
Rumina Hasan ◽  
Shoaib Rao ◽  
Manzoor Ahmed ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
High Risk ◽  
Early Diagnosis ◽  
Hiv Infection ◽  
Hiv Infections ◽  
Risk Groups ◽  
Newly Diagnosed ◽  
Immunodeficiency Virus ◽  
Hiv 1

Human immunodeficiency virus (HIV) infection prevalence in Pakistan has been increasing in high-risk groups, including people who inject drugs (PWID) and transgender hijra sex workers (TG-HSWs) nationwide. Effective control of HIV requires early diagnosis of the infection. We investigated recency of HIV infections in newly-diagnosed cases in PWID and TG-HSWs. This was an observational study with convenience sampling. Overall, 210 HIV-positive subjects comprising an equal number of PWID and TG-HSWs were included. Antibody avidity was tested using the Maxim HIV-1 Limiting Antigen Avidity (LAg) EIA (Maxim Biomedical, Inc. Rockville, Maryland, USA). The mean age of study subjects was 29.5 years: PWID, 28.5 years and TG-HSWs, 30.4 years. Study subjects were married, 27%, or unmarried. Eighteen percent of individuals had recently-acquired HIV infections: 19% of PWID and 17% of TG-HSWs. Eighty-two percent of individuals had long-term HIV infections: 81% of PWID and 83% of TG-HSWs. This is the first study identification of recent HIV-1 infections in Pakistan. We show that most newly-diagnosed HIV patients in the high-risk groups studied had long-term infections. There is an urgent need for intervention in these groups to facilitate early diagnosis and treatment of HIV infection to reduce transmission in Pakistan.

scholarly journals Antiphosphatidylserine antibodies in human immunodeficiency virus-1 patients with evidence of T-cell apoptosis and mediate antibody- dependent cellular cytotoxicity [see comments]

Blood ◽  
1996 ◽  
Vol 87 (12) ◽  
pp. 5185-5195 ◽  
Author(s):  
F Silvestris ◽  
MA Frassanito ◽  
P Cafforio ◽  
D Potenza ◽  
M Di Loreto ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cell ◽  
Cell Apoptosis ◽  
Clinical Feature ◽  
Enzyme Linked Immunosorbent Assay ◽  
Cellular Cytotoxicity ◽  
Antibody Dependent Cellular Cytotoxicity ◽  
T Cell Apoptosis ◽  
Immunodeficiency Virus ◽  
Hiv 1

Serum reactivities to a panel of phospholipid antigens, including cardiolipin (CL), phosphatidylserine (PS), sphingomyelin, phosphatidylcholine, and phosphatidylethanolamine, were measured by enzyme-linked immunosorbent assay in 196 human immunodeficiency virus- l+ (HIV-1+) patients with CDC II to IVC clinical disease. Significant levels of IgG to CL, PS, or both were observed in 23 patients lacking evidence of thrombophilic events or any peculiar clinical feature of HIV-1 infection. Fluorescence-activated cell sorting analyses showed that in vitro apoptosis of T cells was increased in patients with high serum anti-PS IgG, whereas the overexpression of Fas/Apo-1 marker was detected in all patients regardless of their antiphospholipid reactivities. Macrophages from patients with significant titers of anti- PS IgG antibodies were not activated by the presence of apoptotic CEM lymphoblasts or by purified anti-PS IgG from the same patients. By contrast, these antibodies greatly improved the effector functions of autologous macrophages in antibody-dependent cellular cytotoxicity (ADCC) assays using 51Cr-labeled CEM cells, whereas polyspecific IgG were unable to induce an equivalent cytotoxicity in all instances. An increasing effect on ADCC was also observed in tests using macrophages from healthy controls to CEM coated with anti-PS IgG. These results support a potential correlation of anti-PS specificity with T-cell apoptosis in HIV-1 infection. Because PS is exteriorized by apoptotic lymphocytes, its persistence may stimulate antibodies which cooperate with macrophages in the clearance of dead cells by an enhanced ADCC mechanism. This interpretation could explain the absence of thrombophilia in HIV-1+ patients with serum elevations of antiphospholipid reactivities.

scholarly journals Cross-Reactive Human Immunodeficiency Virus Type 1-Neutralizing Human Monoclonal Antibody That Recognizes a Novel Conformational Epitope on gp41 and Lacks Reactivity against Self-Antigens

2008 ◽  
Vol 82 (14) ◽  
pp. 6869-6879 ◽  
Author(s):  
Mei-Yun Zhang ◽  
Bang K. Vu ◽  
Anil Choudhary ◽  
Hong Lu ◽  
Michael Humbert ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Human Immunodeficiency Virus ◽  
Conformational Epitope ◽  
Heptad Repeat ◽  
Enzyme Linked Immunosorbent Assay ◽  
Human Antibody ◽  
Immunodeficiency Virus ◽  
Hiv 1 ◽  
Self Antigens

ABSTRACT Broadly cross-reactive human immunodeficiency virus (HIV)-neutralizing antibodies are infrequently elicited in infected humans. The two best-characterized gp41-specific cross-reactive neutralizing human monoclonal antibodies, 4E10 and 2F5, target linear epitopes in the membrane-proximal external region (MPER) and bind to cardiolipin and several other autoantigens. It has been hypothesized that, because of such reactivity to self-antigens, elicitation of 2F5 and 4E10 and similar antibodies by vaccine immunogens based on the MPER could be affected by tolerance mechanisms. Here, we report the identification and characterization of a novel anti-gp41 monoclonal antibody, designated m44, which neutralized most of the 22 HIV type 1 (HIV-1) primary isolates from different clades tested in assays based on infection of peripheral blood mononuclear cells by replication-competent virus but did not bind to cardiolipin and phosphatidylserine in an enzyme-linked immunosorbent assay and a Biacore assay nor to any protein or DNA autoantigens tested in Luminex assays. m44 bound to membrane-associated HIV-1 envelope glycoproteins (Envs), to recombinant Envs lacking the transmembrane domain and cytoplasmic tail (gp140s), and to gp41 structures containing five-helix bundles and six-helix bundles, but not to N-heptad repeat trimers, suggesting that the C-heptad repeat is involved in m44 binding. In contrast to 2F5, 4E10, and Z13, m44 did not bind to any significant degree to denatured gp140 and linear peptides derived from gp41, suggesting a conformational nature of the epitope. This is the first report of a gp41-specific cross-reactive HIV-1-neutralizing human antibody that does not have detectable reactivity to autoantigens. Its novel conserved conformational epitope on gp41 could be helpful in the design of vaccine immunogens and as a target for therapeutics.

scholarly journals Hospital-Based Evaluation of Two Rapid Human Immunodeficiency Virus Antibody Screening Tests

2000 ◽  
Vol 38 (9) ◽  
pp. 3445-3447 ◽  
Author(s):  
Rajesh Kannangai ◽  
Sandeep Ramalingam ◽  
Selvaraj Pradeepkumar ◽  
Kannan Damodharan ◽  
Gopalan Sridharan
Keyword(s):  
Human Immunodeficiency Virus ◽  
Real Time ◽  
Screening Tests ◽  
Hiv Screening ◽  
Virus Antibody ◽  
Antibody Screening ◽  
Immunodeficiency Virus ◽  
Screening Assays ◽  
Testing Algorithm ◽  
Time Evaluation

Two rapid human immunodeficiency virus (HIV) screening assays, HIV TRI-DOT and HIV-SPOT were compared with standard enzyme-linked immunosorbent assays according to a testing algorithm. Sensitivities and specificities in the real-time evaluation were 99.5 and 99.9% for TRI-DOT and 98.2 and 99.7% for HIV-SPOT, respectively. These two tests are suitable for use where facilities and laboratory expertise are limited.

scholarly journals Implementation of Syringe Services Programs to Prevent Rapid Human Immunodeficiency Virus Transmission in Rural Counties in the United States: A Modeling Study

2019 ◽  
Vol 70 (6) ◽  
pp. 1096-1102 ◽  
Author(s):  
William C Goedel ◽  
Maximilian R F King ◽  
Mark N Lurie ◽  
Sandro Galea ◽  
Jeffrey P Townsend ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Hiv Transmission ◽  
Virus Transmission ◽  
Hiv Infections ◽  
The United States ◽  
Single Infection ◽  
Agent Based ◽  
Immunodeficiency Virus ◽  
Barriers To Implementation ◽  
Scott County

Abstract Background Syringe services programs (SSPs) are effective venues for delivering harm-reduction services to people who inject drugs (PWID). However, SSPs often face significant barriers to implementation, particularly in the absence of known human immunodeficiency virus (HIV) outbreaks. Methods Using an agent-based model, we simulated HIV transmission in Scott County, Indiana, a rural county with a 1.7% prevalence of injection drug use. We compared outcomes arising in the absence of an SSP, in the presence of a pre-existing SSP, and with implementation of an SSP after the detection of an HIV outbreak among PWID over 5 years following the introduction of a single infection into the network. Results In the absence of an SSP, the model predicted an average of 176 infections among PWID over 5 years or an incidence rate of 12.1/100 person-years. Proactive implementation averted 154 infections and decreased incidence by 90.3%. With reactive implementation beginning operations 10 months after the first infection, an SSP would prevent 107 infections and decrease incidence by 60.8%. Reductions in incidence were also observed among people who did not inject drugs. Conclusions Based on model predictions, proactive implementation of an SSP in Scott County had the potential to avert more HIV infections than reactive implementation after the detection of an outbreak. The predicted impact of reactive SSP implementation was highly dependent on timely implementation after detecting the earliest infections. Consequently, there is a need for expanded proactive SSP implementation in the context of enhanced monitoring of outbreak vulnerability in Scott County and similar rural contexts.

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