A genome-wide association study of resistance to HIV infection in highly exposed uninfected individuals with hemophilia A

Human genetic variation contributes to differences in susceptibility to HIV-1 infection. To search for novel host resistance factors, we performed a genome-wide association study (GWAS) in hemophilia patients highly exposed to potentially contaminated factor VIII infusions. Individuals with hemophilia A and a documented history of factor VIII infusions before the introduction of viral inactivation procedures (1979-1984) were recruited from 36 hemophilia treatment centers (HTCs), and their genome-wide genetic variants were compared with those from matched HIV-infected individuals. Homozygous carriers of known CCR5 resistance mutations were excluded. Single nucleotide polymorphisms (SNPs) and inferred copy number variants (CNVs) were tested using logistic regression. In addition, we performed a pathway enrichment analysis, a heritability analysis, and a search for epistatic interactions with CCR5 Δ32 heterozygosity. A total of 560 HIV-uninfected cases were recruited: 36 (6.4%) were homozygous for CCR5 Δ32 or m303. After quality control and SNP imputation, we tested 1 081 435 SNPs and 3686 CNVs for association with HIV-1 serostatus in 431 cases and 765 HIV-infected controls. No SNP or CNV reached genome-wide significance. The additional analyses did not reveal any strong genetic effect. Highly exposed, yet uninfected hemophiliacs form an ideal study group to investigate host resistance factors. Using a genome-wide approach, we did not detect any significant associations between SNPs and HIV-1 susceptibility, indicating that common genetic variants of major effect are unlikely to explain the observed resistance phenotype in this populatio

Early and Prolonged Antiretroviral Therapy Is Associated with an HIV-1-Specific T-Cell Profile Comparable to That of Long-Term Non-Progressors

Background: Intervention with antiretroviral treatment (ART) and control of viral replication at the time of HIV-1 seroconversion may curtail cumulative immunological damage. We have therefore hypothesized that ART maintenance over a very prolonged period in HIV-1 seroconverters could induce an immuno-virological status similar to that of HIV-1 long-term non-progressors (LTNPs).Methodology/Principal Findings: We have investigated a cohort of 20 HIV-1 seroconverters on long-term ART (LTTS) and compared it to one of 15 LTNPs. Residual viral replication and reservoirs in peripheral blood, as measured by cell-associated HIV-1 RNA and DNA, respectively, were demonstrated to be similarly low in both cohorts. These two virologically matched cohorts were then comprehensively analysed by polychromatic flow cytometry for HIV-1-specific CD4(+) and CD8(+) T-cell functional profile in terms of cytokine production and cytotoxic capacity using IFN-gamma, IL-2, TNF-alpha production and perforin expression, respectively. Comparable levels of highly polyfunctional HIV-1-specific CD4(+) and CD8(+) T-cells were found in LTTS and LTNPs, with low perforin expression on HIV-1-specific CD8+ T-cells, consistent with a polyfunctional/non-cytotoxic profile in a context of low viral burden.Conclusions: Our results indicate that prolonged ART initiated at the time of HIV-1 seroconversion is associated with immuno-virological features which resemble those of LTNPs, strengthening the recent emphasis on the positive impact of early treatment initiation and paving the way for further interventions to promote virological control after treatment interruption

Complications of haemophilia therapy

The aim of this thesis is to evaluate and investigate the magnitude of the two major complications of haemophilia treatment: the development of inhibitory antibodies to exogenous clotting factor proteins and blood borne viral infections and their sequelae experienced in a large population of people with haemophilia. All retrospective and prospective studies presented in this thesis have been conducted on a population of 580 haemophilia patients registered through out the years from 1964 to the present time at the Katharine Dormandy Haemophilia Centre and Haemostasis Unit (KDHC and HU), and for whom a comprehensive database has been established. A 25 year follow-up study of 310 patients with inherited bleeding disorders infected with hepatitis C virus between 1961 and 1985 as a result of treatment with non-virally attenuated blood products has shown that 19% of HIV/HCV co-infected patients progressed to liver disease whilst only 3% of HCV mono-infected patients progressed to liver disease. In the era of highly active antiretroviral therapy (HAART) a reduction in the incidence of AIDS has been seen within this cohort, but the death rate has remained high as a consequence of the large number of deaths related to liver disease secondary to chronic hepatitis C infection. Patients with haemophilia who were infected with HIV between 1979-1985 are facing new challenges and complications in the era of HAART such as the unique side-effect of the increased bleeding tendency associated with the use of protease inhibitors. Parvovirus B19, a non-lipid enveloped virus still escapes the virological surveillance system and clinical problems related to this virus have been noted in patients who have contracted this virus through the use of virucidally treated plasma derived clotting factor concentrates. 431 haemophilia A patients of all severities have been followed-up for a total of 5,626 patient years and the frequency of inhibitors was found to be 10% in the severe haemophilia A patients and a third of the inhibitors occurred in children less than 10 years of age. An inhibitor study of 37 previously untreated children with severe haemophilia A who have had treatment with the first heat-treated factor VIII product produced in the United Kingdom showed absence of inhibitors. A series of patients with mild and moderate haemophilia A have developed inhibitors more recently in the KDHC and HU and a change in the practice of replacement therapy in haemophilia may well play a role in the development of these inhibitors. Therapy for haemophilia has progressed substantially not only in the replacement therapeutic materials but also in the treatment strategies and mode of delivery of these therapeutic products. Regular prophylaxis in children with severe haemophilia at our centre has required insertion of central venous catheters because of difficult venous access in some children. A catheter infection rate of 1.74 per 1000 catheter-days has been noted. Thus optimal comprehensive care for this group of patients requires the haemohilia physician to be aware of the complications of therapy: the sequelae of transfusion transmitted infections; the emerging challenges seen in those patients surviving with HIV in the era of HAART; and the development of inhibitory antibodies to replaced clotting factor proteins

Evaluation of the effect on endogenous factor VIII activity (FVIII: C) after recombinant von Willebrand factor (rVWF) administration during the elective surgery study in patients with severe von Willebrand disease (VWD)

WOS: 000431993300190Shire; PfizerPfizer; CSL Behring; Shire Development LLC (Lexington, MA)FP: consultancy (Freeline, Kedrion, Biopharma, LFB, Octapharma); honoraria for participating as a speaker at educational meetings (Ablynx, Bayer, Grifols, Novo Nordisk, Sobi); member of advisory board (Ablynx, F. Hoffmann-La Roche). JDW: research funding (Shire); honoraria (Shire, Bayer, Novo Nordisk). AM, CAMvA, OS, MT, NC, ARC, and TTY: nothing to disclose. KK: honoraria (Shire); member of advisory board (Shire). GC: research funding (directly to institution from Pfizer, CSL Behring); membership on an entity's board of directors, speakers bureau, or its advisory committee (CSL Behring, Shire, Bayer, Sobi, Novo Nordisk, Kedrion, Genzyme, Pfizer). BP and AS are employees of Shire. Funding for development of this abstract was provided by Shire Development LLC (Lexington, MA) to C4 MedSolutions, LLC (Yardley, PA), a CHC Group company

Two classes of germline genes both derived from the V(H)1 family direct the formation of human antibodies that recognize distinct antigenic sites in the C2 domain of factor VIII

Most plasmas from patients with inhibitors contain antibodies that are reactive with the C2 domain of factor VIII. Previously, we have shown that the variable heavy chain (V(H)) regions of antibodies to the C2 domain are encoded by the closely related germline gene segments DP-10, DP-14, and DP-88, which all belong to the V(H)1 gene family. Here, we report on the isolation and characterization of additional anti-C2 antibodies that are derived from V(H) gene segments DP-88 and DP-5. Competition experiments using murine monoclonal antibodies CLB-CAg 117 and ESH4 demonstrated that antibodies derived from DP-5 and DP-88 bound to different sites within the C2 domain. Epitope mapping studies using a series of factor VIII/factor V hybrids revealed that residues 2223 to 2332 of factor VIII are required for binding of the DP-10-, DP-14-, and DP-88-encoded antibodies. In contrast, binding of the DP-5-encoded antibodies required residues in both the amino- and carboxy-terminus of the C2 domain. Inspection of the reactivity of the antibodies with a series of human/porcine hybrids yielded similar data. Binding of antibodies derived from germline gene segments DP-10, DP-14, and DP-88 was unaffected by replacement of residues 2181 to 2243 of human factor VIII for the porcine sequence, whereas binding of the DP-5-encoded antibodies was abrogated by this replacement. Together these data indicate that antibodies assembled from V(H) gene segments DP-5 and the closely related germline gene segments DP-10, DP-14, and DP-88 target 2 distinct antigenic sites in the C2 domain of factor VII

Inhibitors in nonsevere haemophilia A: outcome and eradication strategies

In nonsevere haemophilia A (HA) patients the presence of an inhibitor may exacerbate the bleeding phenotype dramatically. There are very limited data on the optimal therapeutic approach to eradicate inhibitors in these patients. We aimed to describe inhibitor eradication treatment in a large cohort of unselected nonsevere HA patients with inhibitors. We included 101 inhibitor patients from a source population of 2,709 nonsevere HA patients (factor VIII 2-40 IU/dl), treated in Europe and Australia (median age 37 years, interquartile range (IQR) 15-60; median peak titre 7 BU/ml, IQR 2-30). In the majority of the patients (71 %; 72/101) the inhibitor disappeared; either spontaneously (70 %, 51/73) or after eradication treatment (75 %, 21/28). Eradication treatment strategies varied widely, including both immune tolerance induction and immunosuppression. Sustained success (no inhibitor after rechallenge with factor VIII concentrate after inhibitor disappearance) was achieved in 64 % (30/47) of those patients rechallenged with FVIII concentrate. In high-titre inhibitor patients sustained success was associated with eradication treatment (unadjusted relative risk 2.3, 95 % confidence interval 1.3-4.3), compared to no eradication treatment. In conclusion, in nonsevere HA patients most inhibitors disappear spontaneously. However, in 35 % (25/72) of these patients an anamnestic response still can occur when rechallenged, thus disappearance in these patients does not always equal sustained response. Treatment for those requiring eradication has to be decided case by case, as one single approach is unlikely to be appropriate for all. </p