The replication-competent HIV reservoir is a genetically restricted, younger subset of the overall pool of HIV proviruses persisting during therapy, which is highly genetically stable over time

Within-host HIV populations continually diversify during untreated infection, and this diversity persists within infected cell reservoirs during antiretroviral therapy (ART). Achieving a better understanding of on-ART proviral evolutionary dynamics, and a better appreciation of how the overall persisting pool of (largely genetically defective) proviruses differs from the much smaller replication-competent HIV reservoir, is critical to HIV cure efforts. We reconstructed within-host HIV evolutionary histories in blood from seven participants of the Women's Interagency HIV Study who experienced HIV seroconversion, and used these data to characterize the diversity, lineage origins, and ages of proviral env-gp120 sequences sampled longitudinally up to 12 years on ART. We also studied HIV sequences emerging from the reservoir in two participants. We observed that proviral clonality generally increased over time on ART, with clones frequently persisting long term. While on-ART proviral integration dates generally spanned the duration of untreated infection, HIV emerging in plasma was exclusively younger (i.e., dated to the years immediately pre-ART). The genetic and age distributions of distinct proviral sequences remained stable during ART in all but one participant, in whom there was evidence that younger proviruses had been preferentially eliminated after 12 years on ART. Analysis of the gag region in three participants corroborated our env-gp120-based observations, indicating that our observations are not influenced by the HIV region studied. Our results underscore the remarkable genetic stability of the distinct proviral sequences that persist in blood during ART. Our results also suggest that the replication-competent HIV reservoir is a genetically restricted, younger subset of this overall proviral pool.IMPORTANCECharacterizing the genetically diverse HIV sequences that persist in the reservoir despite antiretroviral therapy (ART) is critical to cure efforts. Our observations confirm that proviruses persisting in blood on ART, which are largely genetically defective, broadly reflect the extent of within-host HIV evolution pre-ART. Moreover, on-ART clonal expansion is not appreciably accompanied by the loss of distinct proviral lineages. In fact, on-ART proviral genetic composition remained stable in all but one participant, in whom, after 12 years on ART, proviruses dating to around near ART initiation had been preferentially eliminated. We also identified recombinant proviruses between parental sequence fragments of different ages. Though rare, such sequences suggest that reservoir cells can be superinfected with HIV from another infection era. Overall, our finding that the replication-competent reservoir in blood is a genetically restricted, younger subset of all persisting proviruses suggests that HIV cure strategies will need to eliminate a reservoir that differs in key respects from the overall proviral pool.

Genomic structures and regulation patterns at HPV integration sites in cervical cancer

Human papillomavirus (HPV) integration has been implicated in transforming HPV infection into cancer, but its genomic consequences have been difficult to study using short-read technologies. To resolve the dysregulation associated with HPV integration, we performed long-read sequencing on 63 cervical cancer genomes. We identified six categories of integration events based on HPV-human genomic structures. Of all HPV integrants, defined as two HPV-human breakpoints bridged by an HPV sequence, 24% contained variable copies of HPV between the breakpoints, a phenomenon we termed heterologous integration. Analysis of DNA methylation within and in proximity to the HPV genome at individual integration events revealed relationships between methylation status of the integrant and its orientation and structure. Dysregulation of the human epigenome and neighboring gene expression in cis with the HPV-integrated allele was observed over megabase-ranges of the genome. By elucidating the structural, epigenetic, and allele-specific impacts of HPV integration, we provide insight into the role of integrated HPV in cervical cancer.

The replication-competent HIV reservoir is a genetically restricted, younger subset of the overall pool of HIV proviruses persisting during therapy, which is highly genetically stable over time

Within-host HIV populations continually diversify during untreated infection, and members of these diverse forms persist within infected cell reservoirs, even during antiretroviral therapy (ART). Characterizing the diverse viral sequences that persist during ART is critical to HIV cure efforts, but our knowledge of on-ART proviral evolutionary dynamics remains incomplete, as does our understanding of the differences between the overall pool of persisting proviral DNA (which is largely genetically defective) and the subset of intact HIV sequences capable of reactivating. Here, we reconstructed within-host HIV evolutionary histories in blood from seven participants of the Women's Interagency HIV Study (WIHS) who experienced HIV seroconversion. We measured diversity, lineage origins and ages of proviral sequences (env-gp120) sampled up to four times, up to 12 years on ART. We used the same techniques to study HIV sequences emerging from the reservoir in two participants. Proviral clonality generally increased over time on ART, with clones frequently persisting across multiple time points. The integration dates of proviruses persisting on ART generally spanned the duration of untreated infection (though were often skewed towards years immediately pre-ART), while in contrast, reservoir-origin viremia emerging in plasma was exclusively "younger" (i.e., dated to the years immediately pre-ART). The genetic and age distributions of distinct proviral sequences remained highly stable during ART in all but one participant in whom, after 12 years, there was evidence that "younger" proviruses had been preferentially eliminated. Analysis of within-host recombinant proviral sequences also suggested that HIV reservoirs can be superinfected with virus reactivated from an older era, yielding infectious viral progeny with mosaic genomes of sequences with different ages. Overall, results underscore the remarkable genetic stability of distinct proviral sequences that persist on ART, yet suggest that replication-competent HIV reservoir represents a genetically-restricted and overall "younger" subset of the overall persisting proviral pool in blood.

How well do polygenic risk scores identify men at high risk for prostate cancer? Systematic review and meta-analysis

OBJECTIVES

Genome-wide association studies have revealed over 200 genetic susceptibility loci for prostate cancer (PCa). By combining them, polygenic risk scores (PRS) can be generated to predict risk of PCa. We summarize the published evidence and conduct meta-analyses of PRS as a predictor of PCa risk in Caucasian men.

PATIENTS AND METHODS

Data were extracted from 59 studies, with 16 studies including 17 separate analyses used in the main meta-analysis with a total of 20,786 cases and 69,106 controls identified through a systematic search of ten databases. Random effects meta-analysis was used to obtain pooled estimates of area under the receiver-operating characteristic curve (AUC). Meta-regression was used to assess the impact of number of single-nucleotide polymorphisms (SNPs) incorporated in PRS on AUC. Heterogeneity is expressed as I² scores. Publication bias was evaluated using funnel plots and Egger tests.

RESULTS

The ability of PRS to identify men with PCa was modest (pooled AUC 0.63, 95% CI 0.62-0.64) with moderate consistency (I² 64%). Combining PRS with clinical variables increased the pooled AUC to 0.74 (0.68-0.81). Meta-regression showed only negligible increase in AUC for adding incremental SNPs. Despite moderate heterogeneity, publication bias was not evident.

CONCLUSION

Typically, PRS accuracy is comparable to PSA or family history with a pooled AUC value 0.63 indicating mediocre performance for PRS alone.

A European survey on donor deferral for allergy: Rationale and initial results of a survey in 35 countries

Allergy accounts to near 0.5% of all reported transfusion adverse events. The responsibility of blood components themselves and - therefore - of blood donors is still questioned. The European Community undertook a large international survey to address the consistency and homogeneity of medical selection of blood donors with regard to the risk of allergy, and especially of transferring allergy to recipients. This short report presents the salient points of the survey, stressing that there is inconsistency in addressing the allergy question within countries or systems, with paths of improvement.

Pathogen-reduced Ebola virus convalescent plasma: first steps towards standardization of manufacturing and quality control including assessment of Ebola-specific neutralizing antibodies

BACKGROUND

Ebola virus disease is a public health emergency of international concern, and enormous efforts are being made in the development of vaccines and therapies. Ebola virus convalescent plasma is a promising anti-infective treatment of Ebola virus disease. Therefore, we developed and implemented a pathogen-reduced Ebola virus convalescent plasma concept in accordance with national, European and global regulatory framework.

MATERIALS AND METHODS

Ebola virus convalescent plasma manufacture and distribution was managed by a collection centre, two medical centres and an expert group from the European Blood Alliance. Ebola virus convalescent plasma was collected twice with an interval of 61 days from a donor recovering from Ebola virus disease in Germany. After pathogen reduction, the plasma was analysed for Ebola virus-specific immunoglobulin G (IgG) antibodies and its Ebola virus neutralizing activity.

RESULTS

Convalescent plasma could be collected without adverse events. Anti-Ebola virus IgG titres and Ebola-specific neutralizing antibodies in convalescent plasma were only slightly reduced after pathogen reduction treatment with S59 amotosalen/UVA. A patient in Italy with Ebola virus disease was treated with convalescent plasma without apparent adverse effects.

DISCUSSION

As proof of principle, we describe a concept and practical implementation of pathogen-reduced Ebola virus convalescent plasma manufacture, quality control and its clinical application to an Ebola virus disease patient.

Comparison of autologous serum eye drops with conventional therapy in a randomised controlled crossover trial for ocular surface disease

AIMS

To evaluate the efficacy of 50% autologous serum drops against conventional treatment in ocular surface disorders refractory to normal treatments in a prospective randomised crossover trial.

METHOD

Patients fulfilling ophthalmological and haematological entry criteria were randomised to either 3 months of autologous serum 50% followed by 3 months of their conventional treatment, or 3 months of conventional treatment, followed by 3 months of autologous serum. Clinical assessments, including Schirmer's test, rose Bengal, and fluorescein staining, were carried out on entry and at monthly intervals. Impression cytology was performed at entry, 3 and 6 months. Grading was carried out on degrees of squamous metaplasia and goblet cell density. Subjective comfort was recorded daily using the "faces" scale. These categorical scores were converted to linear measurement using Rasch analysis. Statistical analysis was carried out using Wilcoxon's signed rank test and ANOVA.

RESULTS

16 patients were recruited with 31 eyes studied. The ocular surface diseases chiefly included Sjögren's syndrome (n = 6) and keratoconjunctivitis sicca (n = 5). Impression cytology available in 25 of 31 eyes showed significant improvement on serum treatment, p<0.02. Rasch weighted faces scores were statistically significantly better with serum, p<0.01.

CONCLUSION

The results of this randomised study provide further evidence of the beneficial effects of autologous serum in severe ocular surface disorders. For most of these patients, autologous serum was superior to conventional treatment for improving ocular surface health and subjective comfort.

Cisapride treatment for gastro-oesophageal reflux in children

BACKGROUND

Gastro-oesophageal reflux (GOR) is an extremely common and usually self-limiting condition in infants. When treatment is required, Cisapride, a pro-kinetic agent, has been commonly prescribed for the symptomatic management of GOR. There have been recent reports of possibly serious adverse events, e.g. an increased QTc interval, cardiac arrhythmias, and death, associated with the use of Cisapride.

OBJECTIVES

To determine the effectiveness of Cisapride for symptoms of GOR compared with placebo or any other non-surgical treatments.

SEARCH STRATEGY

Searches were conducted of the Cochrane Central Trials Register and the specialised Trials register of the Cochrane Upper Gastrointestinal and Pancreatic Diseases Group, MEDLINE and Embase up till April 2002. Reference lists of relevant review articles and identified trials were scrutinised and forward citation searches were performed in the Science Citation Index on all trials identified. The search was re-run in August 2003 and no new trials were found.

SELECTION CRITERIA

Randomised controlled trials that compared oral Cisapride therapy with placebo or with other non-surgical treatments for children with a diagnosis of GOR were included. Only studies in which Cisapride was administered orally for a minimum of one week and which documented at least one of the primary outcomes were included. We excluded trials in which the majority of participants were aged less than 28 days.

DATA COLLECTION AND ANALYSIS

The primary outcomes were defined as a change in symptoms at the end of treatment, presence of adverse events, occurrence of clinical complications, and weight gain. The secondary outcomes included physiological measures of GOR or histological evidence of oesophagitis. We dichotomised symptoms into 'same or worse' vs 'improved' and calculated summary odds ratios. Continuous measures of GOR (e.g. reflux index) were summarised as a weighted mean difference. All outcomes were analysed using a random effects method.

MAIN RESULTS

Searches identified nine trials which met the inclusion criteria. Eight trials compared Cisapride with placebo, of which seven (236 participants) reported data on symptoms of gastro-oesophageal reflux, and one reported data on the QTc interval (49 patients). The odds ratio for 'same or worse' vs 'improved symptoms' at the end of treatment of 0.34 (95%CI 0.10, 1.19) did not show a statistically significant difference between the two interventions. There was significant heterogeneity between the studies and the funnel plot suggested publication bias. In a sensitivity analysis, the definition of outcomes was changed to 'any symptoms' vs 'no symptoms'. This resulted in the exclusion of three trials (one of them the largest, best quality trial). The resulting pooled odds ratio showed a significant effect of Cisapride (OR 0.19, 95%CI 0.08, 0.44). Five studies reported adverse events. Four reported adverse events (mainly diarrhoea) but the difference was not statistically significant (OR 1.80, 95%CI 0.87, 3.70). One trial found no difference in the QTc after 3 to 8 weeks of treatment. Cisapride was associated with a statistically significant reduction in the reflux index (weighted mean difference -6.49, 95%CI -10.13, -2.85), but as reflux index and clinical symptoms are poorly correlated, the clinical importance of this finding is uncertain. Other measures of oesophageal pH monitoring did not reach significance. One included study compared Cisapride with Gaviscon (or Gaviscon and Carobel). The odds ratio for 'same or worse' vs 'improvement' in the Cisapride group compared with Gaviscon was 3.26 (95%CI 0.93-11.38).

REVIEWER'S CONCLUSIONS

We found no clear evidence that Cisapride reduces symptoms of GOR. The results suggested substantial publication bias favouring studies showing a positive effect of Cisapride. This finding is supported by the report of one unpublished multi-centre study of 134 patients, which was reported to show no evidence of a significant effect of Cisapride. Due to reports of fatal cardiac arrhythmias or sudden death, from July Due to reports of fatal cardiac arrhythmias or sudden death, from July 2000, cisapride was restricted to a limited access programme supervised by a paediatric gastrologist in the USA and in Europe, to patients treated within a clinical trial or safety study or registry programme.

Survey of the use of whole blood in current blood transfusion practice

Limited use of whole blood has continued despite a general move to blood component therapy in recent years. This paper describes the results of a questionnaire survey which was distributed to haematologists in charge of blood banks in England and North Wales to ascertain how much and for which indications whole blood was being requested. There was a 58% response rate. More than 90% of hospitals that responded had not requested whole blood during the last 12 months. Indications for the use of whole blood were primarily in paediatric practice, mostly for neonatal exchange transfusion or paediatric surgery (cardiac or craniofacial). Infrequent use in adult practice was for "major bleeding" when whole blood was available, and in cardiac surgery, when post-operative bleeding was unresponsive to standard replacement therapy. The evidence for the use of whole blood in preference to component therapy in the massive transfusion setting was reviewed, and no compelling evidence was found for its routine use for this indication. It is worth noting that, as currently supplied in the UK, "whole blood" is not strictly "whole" as the leucocyte-depletion process removes platelets.

The low-incidence MNS antigens M(v), s(D), and Mit arise from single amino acid substitutions on GPB

BACKGROUND

GPB carries 'N' at its N:-terminus and S and s, determined by a polymorphism at amino acid position 29 (Met29Thr). The low-incidence antigens M(v), s(D), and Mit are associated with weakened expression of S and/or s, and the purpose of this study was to define their molecular bases.

METHODS

The GPB gene (GYPB) was sequenced after RT-PCR of RNA from four samples: two M(v)+, one s(D)+, and one Mit+. The point mutations observed were confirmed by sequencing of genomic DNA from these and other examples of s(D)+ and Mit+ samples.

RESULTS

A point mutation of 65C>G observed in the M(v)+ samples predicted a change of Thr3Ser. A mutation of C>G at nucleotide 173 of the GYPB coding sequence, observed in two s(D)+ samples, predicted a change of Pro39Arg. Three Mit+ samples showed a nucleotide substitution of 161G>A, which predicted a change of Arg35His. Altered expression of S or s was confirmed by serologic tests.

CONCLUSION

These results confirm that Arg35 is important for full expression of S. Pro39 and, surprisingly, Thr3 are also important for full expression of s. Furthermore, Thr3 must be essential for expression of 'N,' as M(v)+ RBCs lack 'N.'

Cisapride treatment for gastro-oesophageal reflux in children: a systematic review of randomized controlled trials

The aim of the systematic review was to determine the effect of cisapride compared with placebo or other non-surgical therapies for the treatment of symptoms of gastro-oesophageal reflux in children. We searched MEDLINE, EMBASE, the Cochrane Controlled Trials Register, Science Citation Index and reference lists for randomized controlled trials which compared cisapride with placebo or other non-surgical therapy in children. We included only trials which reported reflux-related symptoms as an outcome, provided that cisapride was administered orally for at least I week. Seven trials (286 children in total) compared cisapride with placebo. Two trials reported good concealment of treatment allocation. The pooled odds ratio for the 'same or worse' symptoms was 0.34 (95% CI 0.10, 1.19). There was substantial heterogeneity between studies (P < 0.00001) and the funnel plot was asymmetrical. Adverse effects (mainly diarrhoea) were not significantly increased with cisapride (pooled odds ratio (OR) 1.80: 0.87, 3.70). The reflux index was significantly reduced in children treated with cisapride (weighted mean difference -6.49: -10.13, -2.85). One study (50 children) compared cisapride with gaviscon plus carobel: the OR for the 'same or worse' symptoms was 3.26 (0.93, 11.38). There was no clear evidence that cisapride reduced symptoms of gastro-oesophageal reflux. As smaller, poorer quality studies were biased in favour of a positive treatment effect, the pooled OR overestimated the potential benefits of cisapride. There was some evidence to suggest that gaviscon plus carobel may be a more effective option than cisapride.

Management of massive blood loss: a template guideline

The management of acute massive blood loss is considered and a template guideline is formulated, supported by a review of the key literature and current evidence. It is emphasized that, if avoidable deaths are to be prevented, surgeons, anaesthetists, haematologists and blood-bank staff need to communicate closely in order to achieve the goals of secure haemostasis, restoration of circulating volume, and effective management of blood component replacement.

Monitoring the clearance of fetal RhD-positive red cells in FMH following RhD immunoglobulin administration

Anti-RhD immunoglobulin was administered to RhD-negative women based on estimates of fetal bleed size obtained using a direct immunofluorescence flow cytometric technique employing a FITC-conjugated monoclonal human anti-D (BRAD 3). The effectiveness of the dose administered was assessed by (i) measuring the fraction of RhD-positive fetal cells in the maternal circulation at d0, and between d2 and d10 post RhD Ig administration, (ii) quantifying the amount of anti-D detectable in maternal plasma following RhD Ig injection in the perinatal period and (iii) assessing maternal serum for the presence of immune anti-D in follow-up samples taken 3 months to 3 years after delivery. Fifty-four women were assessed, 29 having fetal bleeds in excess of 4 mL. Follow-up samples were received from 20/29 mothers after RhD Ig administration; 43-99% and 69-99% of fetal cells had been cleared by d2/3 and d5/6, respectively, in 14/20 mothers, whereas less than 50% had been cleared in the remaining mothers. Long-term follow-up samples were obtained from eight of the 29 mothers (four with bleeds >/=20 mL, two with bleeds >95 mL): none had detectable anti-D in the serum 4 months to 3 years after delivery despite the persistence of up to 36% fetal RhD-positive cells in the maternal circulation six days after delivery.

Variability of polymerase chain reaction detection of the bcl-2-IgH translocation in an international multicentre study

BACKGROUND

The capacity of the polymerase chain reaction (PCR) to detect very low numbers of cells bearing a t(14;18) translocation has led to its application in assessment of the results of treatment for follicular lymphoma, and suggestions that therapy might be guided by molecular studies. To test the reliability of PCR a collaborative study was undertaken to compare results from different laboratories in Europe and North America.

METHODS

Twenty laboratories with records of publication in molecular diagnostics were sent blood from normal donors with varying numbers of t(14;18)-bearing cells added from a cell line with a translocation in the major breakpoint region (MBR) of the bcl-2 gene. Samples contained 1000, 100, 10, 1 or 0 cells per ml of whole blood and were sent blinded in duplicate. PCR methodology varied widely, with the total number of amplification cycles between 30 and 70, and 13 different primers used for the MBR region. Twelve laboratories used nested PCR and eight single round amplification.

RESULTS

The sensitivity of nested and single round PCR was similar at 100 cells/ml but below this the nested method proved significantly more sensitive. The false positive rate was 28%, with 11 samples from 9 laboratories reported as positive when no t(14;18) cells were added. PCR product size and sequence analysis showed that false positives were due to contamination from cell-line DNA rather than background translocations in the donors. There was no significant difference in false positive rates between nested and single round techniques.

CONCLUSION

The polymerase chain reaction to detect bcl-2-IgH rearrangements is presently carried out with widely disparate results. Further effort is required to bring forward a standard PCR protocol which can be re-tested in different laboratories to improve accuracy and reproducibility. The application of quantitative techniques such as real-time PCR may resolve many of the problems presently encountered.

A novel series of 2,5-substituted tryptamine derivatives as vascular 5HT1B/1D receptor antagonists

The design, synthesis, and activity of a novel series of 2,5-substituted tryptamine derivatives at vascular 5HT1B-like receptors is described. Several important auxiliary binding sites of the 5HT1B-like receptor have been proposed following various modifications to the 2-substituent and especially to the methylene- or ethylene-linked 5-side chain. Careful design of new molecules based on a proposed pharmacophoric model of the 5HT1B-like receptor has resulted in the discovery of ethyl 3-[2-(dimethylamino)ethyl]-5-[2-(2, 5-dioxo-1-imidazolidinyl)ethyl]-1H-indole-2-carboxylate (40), a highly potent, silent, competitive, and selective antagonist which shows affinity at the vascular 5HT1B-like receptors only. Changes to the size of the 2-ester substituent have a significant effect on affinity at the 5HT1B-like receptor and other receptors. Prudent placement of the carbonyl substituent in the heterocycle of the 5-side chain is crucial for good affinity and selectivity over the 5HT2A and other receptors. Several key structural and electronic features were identified which are crucial for producing antagonism within a tryptamine-based series. An electron deficient indole ring system appears essential in order to achieve antagonism, and this is achieved by the inclusion of electron-withdrawing groups at the 2-position of the indole ring. The molecule displacement within the receptor resulting from the inclusion of the bulky 2-substituents also enhances antagonism as this results in the removal of the pi electron density of the indole ring from the region of the receptor normally occupied by the indole ring of 5HT. There also appears to be a structural requirement on the side chain incorporating the protonatable nitrogen, and this is achieved by the inclusion of the bulky 2-ester group which neighbors the 3-ethylamine side chain.

A study of anti-hepatitis C positive blood donors: the first year of screening

In the U.K., blood donations have been routinely screened for anti-HCV since September 1991. In order to get the most epidemiological benefit from these extensive screening data, the histories obtained at counselling from donors confirmed to be anti-HCV positive, 'indeterminate' and falsely positive have been analysed in detail. In addition, the associations with potential risk factors have been investigated by comparing these groups of donors with a control group of 771 routine donors bled on one day during the study, at North London Blood Transfusion Centre. This paper documents the prevalence and demography of HCV infection in asymptomatic blood donors, to assess various possible sources of infection and the association between liver function test results and alcohol consumption in donors. One in 1400 previously untested donors was confirmed positive for anti-HCV. Age (the group 30-49 years being highest), tattooing and intravenous drug use in both sexes, ear-piercing in males and blood transfusion in females were all significantly associated with an increased risk of HCV infection. Intravenous drug use proved to be the factor most strongly associated with risk. Liver function tests (alanine aminotransferase) were elevated in a significant number of donors confirmed to be anti-HCV positive but no clear correlation between alanine aminotransferase level and either time since infection or alcohol consumption was found. Alcohol consumption was significantly higher in donors confirmed to be anti-HCV positive and was particularly marked in those admitting to previous intravenous drug use.(ABSTRACT TRUNCATED AT 250 WORDS)

Hodgkin's disease in two sisters

The case histories of two sisters with Hodgkin's disease are reported. Although the disease developed at different ages, the clinical presentation was similar and the histological classification of biopsy material was identical in the two cases. The relative importance of genetic and environmental factors in the aetiology of the disease is discussed.