Low prevalence of HIV in high-risk seronegative homosexual men evidenced by virus culture and polymerase chain reaction

The HIV Seronegative Window Period: Diagnostic Challenges and Solutions

“…A study on the impact of helminthes on the response to immunization in pregnant women and children in Uganda has shown that infection with helminthes has suppressive effects on the immune response (Elliott et al 2007). General immune suppression in MSM would be another example, and in that population a very long WP has been reported (Imagawa et al 1989;Gupta et al 1992). Viral genotypes and clades (Andersson et al 2005), social and environmental factors, and genetics, could also play a role in determining the HIV WP.…”

“…Long term seronegative yet infected state has been reported, especially once more sensitive methods for detecting the virus were developed (Imagawa et al 1989;Ensoli et al 1990;Gupta et al 1992). Incomplete detection of potentially infectious blood units (Ling et al 2000), and other donated organs (e.g.…”

Detection of Antibodies to Human Immunodeficiency Virus (HIV) That Recognize Conformational Epitopes of Glycoproteins 160 and 41 Often Allows for Early Diagnosis of HIV Infection

“…Even with availability of third-generation EIAs, case reports of transmission still appear [70,71]. A number of studies have attempted to shorten the silent period by use of PCR [20][21][22][23][24][25][26]72], but, in general, routine single-amplification regimen PCR for HIV DNA does not detect infection much earlier than the newest EIAs [73]. The new RT-PCR assays for HIV RNA in plasma, however, appear to shorten the window somewhat.…”

“…More important, they may not be able to identify infected persons in the weeks immediately after infection when few, if any, HIV virions (RNA copies) are present in plasma, because the small amount of virus produced within a lymph node draining a mucosal site of HIV entry is very likely "absorbed" by surrounding CD4 T cells and follicular dendritic cells (to which HIV binds with high affinity). In general, earlier studies to determine whether PCR for HIV DNA in blood cells would shorten the diagnostic window found little improvement by use of single amplification regimens [20][21][22][23][24][25][26]. In addition, some studies showed that single PCR amplification regimens were unable to detect the few HIV DNA copies present in ∼10 6 peripheral blood lymphocytes (PBL) during the window period and that nested PCR assays were needed [27][28][29][30].…”

An additional mechanism of growth restriction in T cell line H9 of human immunodeficiency virus type 1 isolates from asymptomatic homosexual men

“…DNA PCR was performed on the lysed cell pellets using oligonucleotides SK38/39 (Wolinsky et al, 1989) as primers to amplify a 114 bp region of gag and primers M667/M844 (Zack et al, 1990) to amplify a 285 bp region spanning the 2LTR junction in circular H1V-1 DNA as previously described (Wolinsky et al, 1989;Gupta et al, 1992). PCR was performed for 30 repeated cycles of target DNA thermal denaturation (94 °C) for 30 s, oligonucleotide primer annealing (55 °C) for 30 s and Taq DNA polymerase-catalysed template extension (72 °C) for 45 s. One-third of the volume of the amplified reaction product was hybridized in solution to a specific a2p end-labelled oligonucleotide probe (200000 c.p.m./sample) derived from an internally conserved sequence in the amplified region (SK19 for the SK38/39 primer pair; KGI (Gupta et al, 1992) for the M661/M667 and M667/M844 primer pairs). The oligonucleotide probe-target DNA was resolved by etectrophoresis on a 10% polyacrylamide gel.…”