HIV pre-exposure prophylaxis and opportunities for vaccination against hepatitis A virus, hepatitis B virus and human papillomavirus: an analysis of the Ontario PrEP cohort study.

OBJECTIVES: Populations who seek HIV pre-exposure prophylaxis (PrEP) are disproportionately affected by hepatitis A virus (HAV), hepatitis B virus (HBV) and human papillomavirus (HPV). We examined immunity/vaccination against these infections among participants in the Ontario PrEP cohort study (ON-PrEP). METHODS: ON-PrEP is a prospective cohort of HIV-negative PrEP users from 10 Ontario clinics. We descriptively analysed baseline immunity/vaccination against HAV (IgG reactive), HBV (hepatitis B surface antibody >10) and HPV (self-reported three-dose vaccination). We further performed multivariable logistic regression to identify characteristics associated with baseline immunity/vaccination. We used cumulative incidence functions to describe vaccine uptake among participants non-immune at baseline. RESULTS: Of 633 eligible participants, 59.1% were white, 85.8% were male and 79.6% were gay. We found baseline evidence of immunity/vaccination against HAV, HBV and HPV in 69.2%, 81.2% and 16.8% of PrEP-experienced participants and 58.9%, 70.3% and 10.4% of PrEP-naïve participants, respectively. Characteristics associated with baseline HAV immunity were greater PrEP duration (adjusted OR (aOR) 1.41/year, 95% CI 1.09 to 1.84), frequent sexually transmitted and bloodborne infection (STBBI) testing (aOR 2.38, 95% CI 1.15 to 4.92) and HBV immunity (aOR 3.53, 95% CI 2.09 to 5.98). Characteristics associated with baseline HBV immunity were living in Toronto (aOR 3.54, 95% CI 1.87 to 6.70) or Ottawa (aOR 2.76, 95% CI 1.41 to 5.40), self-identifying as racialised (aOR 2.23, 95% CI 1.19 to 4.18), greater PrEP duration (aOR 1.39/year, 95% CI 1.02 to 1.90) and HAV immunity (aOR 3.75, 95% CI 2.19 to 6.41). Characteristics associated with baseline HPV vaccination were being aged ≤26 years (aOR 9.28, 95% CI 2.11 to 40.77), annual income between CAD$60 000 and CAD$119 000 (aOR 3.42, 95% CI 1.40 to 8.34), frequent STBBI testing (aOR 7.00, 95% CI 1.38 to 35.46) and HAV immunity (aOR 6.96, 95% CI 2.00 to 24.25). Among those non-immune at baseline, overall cumulative probability of immunity/vaccination was 0.70, 0.60 and 0.53 among PrEP-experienced participants and 0.93, 0.80 and 0.70 among PrEP-naïve participants for HAV, HBV and HPV, respectively. CONCLUSIONS: Baseline immunity to HAV/HBV was common, and a sizeable proportion of non-immune participants were vaccinated during follow-up. However, HPV vaccination was uncommon. Continued efforts should be made to remove barriers to HPV vaccination such as cost, inclusion in clinical guidelines and provider recommendation.

Mechanisms of Hepatocellular Injury in Hepatitis A.

Hepatitis A virus (HAV) infection is a common cause of acute viral hepatitis worldwide. Despite decades of research, the pathogenic mechanisms of hepatitis A remain incompletely understood. As the replication of HAV is noncytopathic in vitro, a widely accepted concept has been that virus-specific cytotoxic T cells are responsible for liver injury. However, accumulating evidence suggests that natural killer (NK) cells, NKT cells, and even non-HAV-specific CD8+ T cells contribute to liver damage during HAV infection. In addition, intrinsic death of virus-infected hepatocytes has been implicated as a cause of liver injury in a murine model of hepatitis A. Furthermore, genetic variations in host factors such as T cell immunoglobulin-1 (TIM1) and IL-18 binding protein (IL-18BP) have been linked to hepatitis A severity. This review summarizes the current knowledge of the mechanisms of hepatocellular injury in hepatitis A. Different mechanisms may be involved under different conditions and they are not necessarily mutually exclusive. A better understanding of these mechanisms would aid in diagnosis and treatment of diseases associated with HAV infection.

Prognostic, clinical, and therapeutic importance of RANTES-CCR5 axis in hepatitis A infection: A multiapproach study.

Fulminant hepatic failure (FHF) is a lethal manifestation of hepatitis A virus (HAV) infection, whose underlying mechanisms are poorly understood. We aimed to evaluate the importance of the modulation of the RANTES-chemokine receptor type 5 (CCR5) signaling axis and its immunomodulatory effects in directing hepatitis A disease pathogenesis using an in silico, in vitro and patient cohort-based approach. In silico interaction studies were performed using computation approaches with suitable software. Differential expression of relevant cytokines and immune cell markers were studied using real-time quantitative reverse transcription PCR (qRT-PCR), enzyme-linked immunosorbent assay, and flow-cytometry-based methods. In the HepG2 cell line, we studied inflammatory responses and susceptibility to HAV infection following RANTES stimulation and antibody blockade of CCR5. The HAV-VP3 region exhibited high interaction in CCR5: HAV complexes. RANTES levels were significantly increased in FHF cases. Reduced monocyte and T-cell activation were observed in FHF cases. RANTES expression inversely correlated with viremia but positively correlated with proinflammatory responses. Hyper Th1-biased immune responses, marked by high interleukin (IL)-12/IL-10 ratio were observed in FHF cases, which were also characterized by upregulated tumor necrosis factor-alpha (TNF-α) expression and reduced interferon-gamma expression. In vitro, RANTES was protective against HAV infection but resulted in upregulated TNF-α expression. Although viral load increased upon the regulation of inflammatory responses by CCR5 blocking, it was still significantly lower compared to control HAV-infected cells. Our study suggests the importance of RANTES-CCR5 signaling and linked-immunomodulation in HAV disease pathogenesis, as well as highlights the utility of CCR5 antagonists as a risk-reduction strategy in FHF patients. Our findings, therefore, have important implications for the management of high-risk HAV infections.

Polyvalent Human Immune Globulin: A Prospective, Open-Label Study Assessing Anti-Hepatitis A Virus (HAV) Antibody Levels, Pharmacokinetics, and Safety in HAV-Seronegative Healthy Subjects.

BACKGROUND: Analytical data suggesting that immunoglobulin given intramuscularly (IGIM) may have reduced protection against hepatitis A virus (HAV) infection led to an update in the recommended IGIM dose (0.2 ml/kg). METHODS: This prospective, open-label, single-arm clinical study evaluated whether a single 0.2 ml/kg dose of IGIM provided protective levels of anti-HAV antibodies (≥ 10 mIU/ml for up to 60 days) in HAV-seronegative healthy adults. RESULTS: Of the 28 subjects enrolled and dosed, 26 (93%) completed the study. Mean uncorrected anti-HAV antibody titers peaked at 109 mIU/ml on day 5 and stayed above 10 mIU/ml through day 60 (N = 26). The mean uncorrected anti-HAV antibody titers had a median Tmax of 95.33 h, a mean Cmax of 118 mIU/ml, and a mean observed Thalf of 63.3 days; baseline-corrected titers had a median Tmax of 95.33 h, a mean Cmax of 114 mIU/ml, and a mean observed Thalf of 47.1 days (N = 27). All subjects (28/28) experienced at least 1 treatment-emergent adverse event (TEAE), with a total of 83 TEAEs reported; none was serious, and 96% (80/83) resolved without sequelae. Most (63%) events judged definitely and possibly related to study treatment involved localized pain due to intramuscular injections. There were no serious adverse events and no deaths or discontinuations due to TEAEs. CONCLUSIONS: A single 0.2 ml/kg dose of IGIM provided protective anti-HAV levels for at least 60 days, with acceptable safety and tolerability profiles in healthy subjects. Uncorrected and baseline-corrected pharmacokinetic findings were similar and consistent with the corresponding sampling points in previous research. TRIAL REGISTRATION: ClinicalTrials.gov Identifier, NCT03351933.

Transfusion transmission of hepatitis A virus with fecal shedding in a previously hepatitis A vaccinated recipient.

We describe a rare case of hepatitis A virus (HAV) replication in feces despite presence of hepatitis A antibodies in an acute myeloid leukemia (AML) patient after transfusion with HAV contaminated platelets. The patient has been vaccinated against HAV years before the AML diagnosis. Transient infection and reshedding should thus be considered in antibody-positive hematological patients. Transfusion associated HAV transmission is rare, and little evidence exists on the clinical consequences and possible effect of treatment with immunoglobulin. Further reporting on fecal shedding despite antibodies are needed, as HAV antibody levels are used as course of action for post-exposure prophylaxis and infection control.

Duck hepatitis A virus structural proteins expressed in insect cells self-assemble into virus-like particles with strong immunogenicity in ducklings.

Duck hepatitis A virus (DHAV), a non-enveloped ssRNA virus, can cause a highly contagious disease in young ducklings. The three capsid proteins of VP0, VP1 and VP3 are translated within a single large open reading frame (ORF) and hydrolyzed by protease 3CD. However, little is known on whether the recombinant viral structural proteins (VPs) expressed in insect cells could spontaneously assemble into virus-like particles (VLPs) and whether these VLPs could induce protective immunity in young ducklings. To address these issues, the structural polyprotein precursor gene P1 and the protease gene 3CD were amplified by PCR, and the recombinant proteins were expressed in insect cells using a baculovirus expression system for the characterization of their structures and immunogenicity. The recombinant proteins expressed in Sf9 cells were detected by indirect immunofluorescence assay and Western blot analysis. Electron microscopy showed that the recombinant proteins spontaneously assembled into VLPs in insect cells. Western blot analysis of the purified VLPs revealed that the VLPs were composed with the three structural proteins. In addition, vaccination with the VLPs induced high humoral immune response and provided strong protection. Therefore, our findings may provide a framework for development of new vaccines for the prevention of duck viral hepatitis.

Tumor Necrosis Factor-producing T-regulatory Cells Are Associated With Severe Liver Injury in Patients With Acute Hepatitis A.

BACKGROUND AND AIMS: CD4+CD25+Foxp3+ T-regulatory (Treg) cells control immune responses and maintain immune homeostasis. However, under inflammatory conditions, Treg cells produce cytokines that promote inflammation. We investigated production of tumor necrosis factor (TNF) by Treg cells in patients with acute hepatitis A (AHA), and examined the characteristics of these cells and association with clinical factors. METHODS: We analyzed blood samples collected from 63 patients with AHA at the time of hospitalization (and some at later time points) and 19 healthy donors in South Korea. Liver tissues were collected from patients with fulminant AHA during liver transplantation. Peripheral blood mononuclear cells were isolated from whole blood and lymphocytes were isolated from liver tissues and analyzed by flow cytometry. Cytokine production from Treg cells (CD4+CD25+Foxp3+) was measured by immunofluorescence levels following stimulation with anti-CD3 and anti-CD28. Epigenetic stability of Treg cells was determined based on DNA methylation patterns. Phenotypes of Treg cells were analyzed by flow cytometry and an RORγt inhibitor, ML-209, was used to inhibit TNF production. Treg cell suppression assay was performed by co-culture of Treg-depleted peripheral blood mononuclear cells s and isolated Treg cells. RESULTS: A higher proportion of CD4+CD25+Foxp3+ Treg cells from patients with AHA compared with controls produced TNF upon stimulation with anti-CD3 and anti-CD28 (11.2% vs 2.8%). DNA methylation analysis confirmed the identity of the Treg cells. TNF-producing Treg cells had features of T-helper 17 cells, including up-regulation of RORγt, which was required for TNF production. The Treg cells had reduced suppressive functions compared with Treg cells from controls. The frequency of TNF-producing Treg cells in AHA patients' blood correlated with their serum level of alanine aminotransferase. CONCLUSIONS: Treg cells from patients with AHA have altered functions compared with Treg cells from healthy individuals. Treg cells from patients with AHA produce higher levels of TNF, gain features of T-helper 17 cells, and have reduced suppressive activity. The presence of these cells is associated with severe liver injury in patients with AHA.

Validation of HAV biomarker 2A for differential diagnostic of hepatitis A infected and vaccinated individuals using multiplex serology.

BACKGROUND: Worldwide about 1.5 million clinical cases of hepatitis A virus (HAV) infections occur every year and increasingly countries are introducing HAV vaccination into the childhood immunization schedule with a single dose instead of the originally licenced two dose regimen. Diagnosis of acute HAV infection is determined serologically by anti-HAV-IgM detection using ELISA. Additionally anti-HAV-IgG can become positive during the early phase of symptoms, but remains detectable after infection and also after vaccination against HAV. Currently no serological marker allows the differentiation of HAV vaccinated individuals and those with a past infection with HAV. Such differentiation would greatly improve evaluation of vaccination campaigns and risk assessment of HAV outbreaks. Here we tested the HAV non-structural protein 2A, important for the capsid assembly, as a biomarker for the differentiation of the immune status in previously infected and vaccinated individuals. METHODS: HAV antigens were recombinantly expressed as glutathione-S-transferase (GST) fusion proteins. Using glutathione tagged, magnetic fluorescent beads (Luminex®), the proteins were affinity purified and used in a multiplex serological assay. The multiplex HAV assay was validated using 381 reference sera in which the immune status HAV negative, vaccinated or infected was established using the Abbott ARCHITECT® HAVAb-IgM or IgG, the commercial HAV ELISA from Abnova and documentation in vaccination cards. RESULTS: HAV multiplex serology showed a sensitivity of 99% and specificity of 95% to detect anti-HAV IgG/IgM positive individuals. HAV biomarker 2A allowed the differentiation between previously infected and vaccinated individuals. HAV vaccinated individuals and previously infected individuals could be identified with 92% accuracy. CONCLUSION: HAV biomarker 2A can be used to differentiate between previously HAV-vaccinated and naturally infected individuals. Within a multiplex serological approach this assay can provide valuable novel information in the context of outbreak investigations, longitudinal population based studies and evaluations of immunization campaigns.

Recombinant VP1 protein as a potential marker for the diagnosis of acute hepatitis A virus infection.

Since hepatitis A virus (HAV) production is time-consuming and expensive, the use of recombinant proteins may represent an alternative source of antigens for diagnostic purposes. The present study aimed to express, purify and evaluate the potential of recombinant VP1 protein (rVP1) as a marker for the diagnosis of acute HAV infection. The rVP1 was expressed and purified successfully from Escherichia coli. The purified rVP1 was used to establish an in-house enzyme-linked immunosorbent assay (ELISA-rVP1) for detection of IgM antibodies in sera from HAV-positive patients. For a cut-off point of 0.351, the sensitivity and specificity of ELISA-rVP1 were 100.0% and 95.0%, respectively. These results indicate that rVP1 may be a useful antigen for detection of IgM antibodies against HAV.

An outbreak of hepatitis A virus among children in a flood rescue camp: A post-disaster catastrophe.

We report an outbreak of acute viral hepatitis among children in a flood rescue camp at Rudraprayag district of Uttarakhand State, India. In May 2013, there was a disastrous natural calamity, The Himalayan Tsunami in Himalayan and Sub-Himalayan region of Uttarakhand. More than 5700 people were feared dead, and thousands were sheltered in different rescue camps. A linkage was hypothesised between the infected individuals and the common water sources feared of being contaminated faecally. Aetiological agent of the present outbreak was HAV that is emerging in an outbreak form in India, emphasizing a definite need for formulating mandatory vaccination and proper control strategies. The report exemplifies the basic problems encountered after a natural calamity.

Cynomolgus monkeys (Macaca fascicularis) experimentally infected with B19V and hepatitis A virus: no evidence of the co-infection as a cause of acute liver failure

This study was conducted to analyse the course and the outcome of the liver disease in the co-infected animals in order to evaluate a possible synergic effect of human parvovirus B19 (B19V) and hepatitis A virus (HAV) co-infection. Nine adult cynomolgus monkeys were inoculated with serum obtained from a fatal case of B19V infection and/or a faecal suspension of acute HAV. The presence of specific antibodies to HAV and B19V, liver enzyme levels, viraemia, haematological changes, and necroinflammatory liver lesions were used for monitoring the infections. Seroconversion was confirmed in all infected groups. A similar pattern of B19V infection to human disease was observed, which was characterised by high and persistent viraemia in association with reticulocytopenia and mild to moderate anaemia during the period of investigation (59 days). Additionally, the intranuclear inclusion bodies were observed in pro-erythroblast cell from an infected cynomolgus and B19V Ag in hepatocytes. The erythroid hypoplasia and decrease in lymphocyte counts were more evident in the co-infected group. The present results demonstrated, for the first time, the susceptibility of cynomolgus to B19V infection, but it did not show a worsening of liver histopathology in the co-infected group.

Comparative Analysis of Liver Injury-Associated Cytokines in Acute Hepatitis A and B.

PURPOSE: Acute hepatitis A (AHA) and acute hepatitis B (AHB) are caused by an acute infection of the hepatitis A virus and the hepatitis B virus, respectively. In both AHA and AHB, liver injury is known to be mediated by immune cells and cytokines. In this study, we measured serum levels of various cytokines and T-cell cytotoxic proteins in patients with AHA or AHB to identify liver injury-associated cytokines. MATERIALS AND METHODS: Forty-six patients with AHA, 16 patients with AHB, and 14 healthy adults were enrolled in the study. Serum levels of 17 cytokines and T-cell cytotoxic proteins were measured by enzyme-linked immunosorbent assays or cytometric bead arrays and analyzed for correlation with serum alanine aminotransferase (ALT) levels. RESULTS: Interleukin (IL)-18, IL-8, CXCL9, and CXCL10 were significantly elevated in both AHA and AHB. IL-6, IL-22, granzyme B, and soluble Fas ligand (sFasL) were elevated in AHA but not in AHB. In both AHA and AHB, the serum level of CXCL10 significantly correlated with the peak ALT level. Additionally, the serum level of granzyme B in AHA and the serum level of sFasL in AHB correlated with the peak ALT level. CONCLUSION: We identified cytokines and T-cell cytotoxic proteins associated with liver injury in AHA and AHB. These findings deepen the existing understanding of immunological mechanisms responsible for liver injury in acute viral hepatitis.

DDX60L Is an Interferon-Stimulated Gene Product Restricting Hepatitis C Virus Replication in Cell Culture.

UNLABELLED: All major types of interferon (IFN) efficiently inhibit hepatitis C virus (HCV) replication in vitro and in vivo. Remarkably, HCV replication is not sensitive to IFN-γ in the hepatoma cell line Huh6, despite an intact signaling pathway. We performed transcriptome analyses between Huh6 and Huh-7 cells to identify effector genes of the IFN-γ response and thereby identified the DExD/H box helicase DEAD box polypeptide 60-like (DDX60L) as a restriction factor of HCV replication. DDX60L and its homolog DEAD box polypeptide 60 (DDX60) were both induced upon viral infection and IFN treatment in primary human hepatocytes. However, exclusively DDX60L knockdown increased HCV replication in Huh-7 cells and rescued HCV replication from type II IFN as well as type I and III IFN treatment, suggesting that DDX60L is an important effector protein of the innate immune response against HCV. In contrast, we found no impact of DDX60L on replication of hepatitis A virus. DDX60L protein was detectable only upon strong ectopic overexpression, displayed a broad cytoplasmic distribution, but caused cytopathic effects under these conditions. DDX60L knockdown did not alter interferon-stimulated gene (ISG) induction after IFN treatment but inhibited HCV replication upon ectopic expression, suggesting that it is a direct effector of the innate immune response. It most likely inhibits viral RNA replication, since we found neither impact of DDX60L on translation or stability of HCV subgenomic replicons nor additional impact on assembly of infectious virus. Similar to DDX60, DDX60L had a moderate impact on RIG-I dependent activation of innate immunity, suggesting additional functions in the sensing of viral RNA. IMPORTANCE: Interferons induce a plethora of interferon-stimulated genes (ISGs), which are our first line of defense against viral infections. In addition, IFNs have been used in antiviral therapy, in particular against the human pathogen hepatitis C virus (HCV); still, their mechanism of action is not well understood, since diverse, overlapping sets of antagonistic effector ISGs target viruses with different biologies. Our work identifies DDX60L as a novel factor that inhibits replication of HCV. DDX60L expression is regulated similarly to that of its homolog DDX60, but our data suggest that it has distinct functions, since we found no contribution of DDX60 in combatting HCV replication. The identification of novel components of the innate immune response contributes to a comprehensive understanding of the complex mechanisms governing antiviral defense.

Using immunoglobulin Y as an alternative antibody for the detection of hepatitis A virus in frozen liver sections

An increasing amount of research has been conducted on immunoglobulin Y (IgY) because the use of IgY offers several advantages with respect to diagnostic testing, including its easy accessibility, low cost and translatability to large-scale production, in addition to the fact that it can be ethically produced. In a previous work, immunoglobulin was produced and purified from egg yolks (IgY) reactive to hepatitis A virus (HAV) antigens. In the present work, this anti-HAV-specific IgY was used in an indirect immunofluorescence assay to detect viral antigens in liver biopsies that were obtained from experimentally infected cynomolgus monkeys. Fields that were positive for HAV antigen were detected in liver sections using confocal microscopy. In conclusion, egg yolks from immunised hens may be a reliable source for antibody production, which can be employed for immunological studies.

Enhanced mucosal immune responses induced by a combined candidate mucosal vaccine based on Hepatitis A virus and Hepatitis E virus structural proteins linked to tuftsin.

Hepatitis A virus (HAV) and Hepatitis E virus (HEV) are the most common causes of infectious hepatitis. These viruses are spread largely by the fecal-oral route and lead to clinically important disease in developing countries. To evaluate the potential of targeting hepatitis A and E infection simultaneously, a combined mucosal candidate vaccine was developed with the partial open reading frame 2 (ORF2) sequence (aa 368-607) of HEV (HE-ORF2) and partial virus protein 1 (VP1) sequence (aa 1-198) of HAV (HA-VP1), which included the viral neutralization epitopes. Tuftsin is an immunostimulatory peptide which can enhance the immunogenicity of a protein by targeting it to macrophages and dendritic cells. Here, we developed a novel combined protein vaccine by conjugating tuftsin to HE-ORF2 and HA-VP1 and used synthetic CpG oligodeoxynucleotides (ODNs) as the adjuvant. Subsequent experiments in BALB/c mice demonstrated that tuftsin enhanced the serum-specific IgG and IgA antibodies against HEV and HAV at the intestinal, vaginal and pulmonary interface when delivered intranasally. Moreover, mice from the intranasally immunized tuftsin group (HE-ORF2-tuftsin + HA-VP1-tuftsin + CpG) showed higher levels of IFN-γ-secreting splenocytes (Th1 response) and ratio of CD4+/CD8+ T cells than those of the no-tuftsin group (HE-ORF2 + HA-VP1 + CpG). Thus, the tuftsin group generated stronger humoral and cellular immune responses compared with the no-tuftsin group. Moreover, enhanced responses to the combined protein vaccine were obtained by intranasal immunization compared with intramuscular injection. By integrating HE-ORF2, HA-VP1 and tuftsin in a vaccine, this study validated an important concept for further development of a combined mucosal vaccine against hepatitis A and E infection.

Seroprevalence of hepatitis A,B, and C viruses in Turkish alcoholic cirrhotics and the impact of hepatitis B on clinical profile.

INTRODUCTION: The aims of this study were to detect the seroprevalence of hepatitis A, B, and C viruses in Turkish alcoholic cirrhotics, and to evaluate the impact of hepatitis B infection on clinical profile at first admittance. METHODOLOGY: Serological markers for hepatitis A, B, and C viruses in 300 alcoholic cirrhotics diagnosed between January 1994 and December 2012 were retrospectively reviewed. Among them, 148 eligible patients were divided into group 1 (HBsAg positive, n = 43) and group 2 (HBsAg and anti-HBc negative, n = 105). Clinical characteristics at first admittance of groups 1 and 2 were compared. RESULTS: The seroprevalence of anti-HAV total, HBsAg, and anti-HCV was found to be 91.5%, 16.3%, and 8.2%, respectively. The prevalence of hepatocellular carcinoma was higher in the HbsAg-positive group compared to HbsAg- and anti-HBc-negative group (16.3% vs. 2.9%, p = 0.007). Other clinical features were similar in the two groups. CONCLUSIONS: Alcoholic cirrhotics have higher frequencies of HBsAg and anti-HCV than the general population. These patients should be investigated for coexistent HBV and HCV infections, and HBV vaccination should not be neglected. Alcoholic cirrhotic patients with concomitant HBV infection should be closely screened for hepatocellular carcinoma.

Adherence to hepatitis A virus vaccination in HIV-infected men who have sex with men.

Although vaccination against hepatitis A virus (HAV) is essential for human immunodeficiency virus (HIV)-infected patients, the uptake of HAV vaccine is reported to be very low. From 2007 to 2012, 912 HIV-infected men in Athens, Greece were screened for exposure to HAV. Two doses of an HAV vaccine were recommended to 569 eligible patients. Reminder cards with scheduled vaccination visits were given to each patient. Among eligible patients, 62.2% (354/569) received both doses. Patients who were fully vaccinated compared with non-adherent patients were natives, older, had undetectable HIV viral load, higher CD4 T cell counts and lower nadir CD4 T cell counts. Multivariate logistic regression revealed that the patient's country of origin (p = 0.024; OR = 2.712; 95% CI, 1.139-6.457), CD4 T cell count (p < 0.001) and nadir CD4 T cell count (p < 0.001) were factors directly associated with adherence. In conclusion, adherence to HAV vaccination was better than in previously published data. Because many of the factors related to vaccination completion are parameters of HIV infection, it appears that physician interest in HIV care and vaccination planning is crucial to enhancing vaccine uptake.

Impact of smoking on the quantity and quality of antibodies induced by human papillomavirus type 16 and 18 AS04-adjuvanted virus-like-particle vaccine - a pilot study.

BACKGROUND: The AS04-adjuvanted bivalent L1 virus-like-particle (VLP) vaccine (Cervarix™) against infection with human papillomavirus (HPV) types 16/18 holds great promise to prevent HPV16/18 infections and associated neoplasias, but it is important to rule out significant co-factors of the neoplasias like smoking. METHODS: We conducted a pilot study to compare the quantity and quality of HPV16/18 antibody response at baseline and 7 months post vaccination in 104 non-smoking and 112 smoking female participants vaccinated at 0, 1 and 6 months with Cervarix™ (55 and 48 study participants) or with Hepatitis A vaccine (HAVRIX™) (48 and 64 participants, respectively). These 216 women were a sub-sample of 4808 baseline 16- to 17-year old Finnish women initially enrolled in the double-blind, randomized controlled phase III PATRICIA trial. Following end-of-study unblinding in 2009 they were randomly chosen out of all the participants of the three major Finnish PATRICIA study sites in the Helsinki metropolitan area (University of Helsinki, N = 535, and Family Federation Finland, N = 432) and Tampere (University of Tampere, N = 428). Following enrolment, serum samples were collected at month 0 and month 7 post 1st vaccination shot, and were analysed for levels and avidity of IgG antibodies to HPV16 and HPV18 using standard and modified (4 M urea elution) VLP ELISAs. RESULTS: We found that at month 7 post vaccination women who smoked (cotinine level > 20 ng/ml) had levels of anti-HPV16/18 antibodies comparable to those of non-smoking women. Low-avidity HPV16/18 IgG antibodies were observed in 16% of the vaccinated women, and active smoking conferred a three-fold increased risk (95% CI 1.0-9.3) of having the low-avidity antibodies. CONCLUSION: Our data suggest that while smoking does not interfere with the quantity of vaccine-induced peak IgG levels, it may affect the avidity of IgG induced by HPV16/18 vaccination.

Stability studies of binding and functional anti-vaccine antibodies.

BACKGROUND: As most vaccines exert their protective capacity by eliciting pathogen-specific antibodies, antibody assays assessing immunogenicity of vaccines in development should be well characterized. Part of the validation of immunogenicity assays for vaccines is the study of stability of antibodies in serum. Materials & methods: Stability of antibodies in human serum was assessed by circumsporozoite-binding IgG ELISA designed for assessing the immunogenicity of a malaria vaccine under development, adenovirus neutralization assay, designed to assess neutralizing antibodies against adenovirus and commercially available test kits for hepatitis A and B. RESULTS: Stability studies indicated stability of serum-binding IgG antibodies and serum-neutralizing antibodies in: long-term storage below -65°C and -20°C; short-term storage; multiple freeze/thaw rounds; during shipment; and during heat inactivation. CONCLUSION: RESULTS have shown the stability of both binding and functional polyclonal antibodies in human serum under stable storage and common usage circumstances.