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Abstract: Background and objectives: Minority drug-resistant HIV-1 variants, undetected by conventional genotyping, may impair the outcome of antiretroviral therapy (ART). Thus, we retrospectively analyzed the prevalence of minority drug-resistant HIV-1 variants before ART in chronically HIV-1 infected patients initiating first-line therapy and assessed the impact on clinical outcome in the prospective German Truvada cohort. Study design: Samples from 146 antiretroviral treatment-naïve patients were collected between April 2005 and August 2006. K65R, K103N, and M184V variants at low frequencies were detected by allele-specific real-time PCR. Results: Minority drug-resistant HIV-1 variants were detected in 20/146 patients (13.7%): the M184V mutation in 12/146 patients (8.2%), the K103N mutation in 8/146 patients (5.5%), and the K65R mutation in 4/146 patients (2.7%). Four patients with the M184V mutation also harbored the K65R or the K103N mutation. The 12- and 24 months virological efficacy data revealed that the rate of treatment failure was not increased in the group of patients harboring minority drug-resistant HIV-1 variants prior to ART. Conclusions: Minority drug-resistant HIV-1 variants can be frequently detected in treatment-naïve, chronically HIV-1 infected patients. Despite the presence of those mutations as minority variants before initiating ART, most of the patients were successfully treated. [ABSTRACT FROM AUTHOR]

A single virus is capable of infecting and replicating in a single cell. Recent advances across single-cell omics technologies – genomics, epigenomics, transcriptomics, epitranscriptomics, proteomics, and metabolomics – will offer unprecedented opportunities to gain more insights into the various aspects of the life cycle of viruses and their impact on the host cell. Here, using the human immunodeficiency virus type 1 (HIV-1) as an example, we summarize the current knowledge and the future potential of single-cell omics in the investigation of an important aspect of the life cycle of HIV-1 that represents a major hurdle in achieving viral eradication, HIV-1 latency. [ABSTRACT FROM AUTHOR]

Abstract: Background: IgE sensitisation to non-specific lipid transfer proteins (nsLTP), e.g., Pru p 3 the major allergen from peach and most important allergenic LTP, is strongly associated with severe symptoms in food allergic patients. Lac s 1, a member of the nsLTP protein family, was recently identified as major allergen in lettuce (Lactuca sativa), but has not yet been investigated on the molecular basis. Objective: Molecular characterisation and immunological comparison of Lac s 1 to peach allergen Pru p 3. Methods: Lac s 1 cDNA was cloned by RT-PCR and natural (n) Lac s 1 was purified by a two-step chromatography. Protein structure was verified by N-terminal sequencing, mass spectrometry, and circular dichroism spectroscopy. Immunoblotting, ImmunoCAP™, and competitive IgE binding experiments were performed to study the IgE sensitisation pattern and cross-reactivity with Pru p 3. Allergenic potency was analysed by histamine release assay. Results: Twenty-nine lettuce allergic patients, with or without concomitant peach allergy, and 19 peach allergic patients without lettuce allergy were included in this study. IgE reactivity to lettuce was due to mono-sensitisation to Lac s 1 or cross-reactive glycan structures. Two Lac s 1 isoforms were identified which showed amino acid identitiy (aa-id) of 62% to each other, up to 66% to Pru p 3, and 72% to the N-terminal peptide of plane pollen LTP Pla a 3. The prevalence of IgE binding to nLac s 1 was 90% using lettuce extract in immunoblotting experiments. Enhanced sensitivity was observed in ImmunoCAP™ using purified nLac s 1 in comparison to extracts (93% versus 76%). Although IgE sensitisation to Lac s 1 and Pru p 3 was strongly associated, the two LTPs showed different IgE binding properties. Sensitisation to LTPs does not necessarily reflect the clinical disease, but Lac s 1 was capable of triggering histamine release as shown by positive skin test results in Lac s 1 mono-sensitised patients and by in vitro mediator release assays. Conclusion: Purified nLac s 1 will enhance the sensitivity in component resolved diagnosis of lettuce allergy. Similar to other cross-reactive food allergies, exclusive testing of IgE reactivities to LTP cannot be used as biomarker for clinical relevance. Our data provide indirect evidence that Pru p 3 might act as the primary sensitising agent in patients allergic to both lettuce and peach. [Copyright &y& Elsevier]