Efficacy, Immunogenicity, and Safety of a 9-Valent Human Papillomavirus Vaccine: Subgroup Analysis of Participants From Asian Countries.

Background: A 9-valent human papillomavirus-6/11/16/18/31/33/45/52/58 (9vHPV) vaccine extends coverage to 5 next most common oncogenic types (31/33/45/52/58) in cervical cancer versus quadrivalent HPV (qHPV) vaccine. We describe efficacy, immunogenicity, and safety in Asian participants (India, Hong Kong, South Korea, Japan, Taiwan, and Thailand) from 2 international studies: a randomized, double-blinded, qHPV vaccine-controlled efficacy study (young women aged 16-26 years; NCT00543543; Study 001); and an immunogenicity study (girls and boys aged 9-15 years; NCT00943722; Study 002). Methods: Participants (N = 2519) were vaccinated at day 1 and months 2 and 6. Gynecological samples (Study 001 only) and serum were collected for HPV DNA and antibody assessments, respectively. Injection-site and systemic adverse events (AEs) were monitored. Data were analyzed by country and vaccination group. Results: 9vHPV vaccine prevented HPV-31/33/45/52/58-related persistent infection with 90.4%-100% efficacy across included countries. At month 7, ≥97.9% of participants seroconverted for each HPV type. Injection-site AEs occurred in 77.7%-83.1% and 81.9%-87.5% of qHPV and 9vHPV vaccine recipients in Study 001, respectively, and 62.4%-85.7% of girls/boys in Study 002; most were mild to moderate. Conclusions: The 9vHPV vaccine is efficacious, immunogenic, and well tolerated in Asian participants. Data support 9vHPV vaccination programs in Asia. Clinical Trials Registration: NCT00543543; NCT00943722.

Safety profile of the 9-valent human papillomavirus vaccine: assessment in prior quadrivalent HPV vaccine recipients and in men 16 to 26 years of age.

A 9-valent HPV (9vHPV) vaccine has been developed to protect against HPV type 6/11/16/18/31/33/45/52/58-related infection and disease. Previous safety analyses from 7 clinical trials conducted in 9vHPV vaccine recipients 9-26 years of age, including comparisons of 9vHPV and quadrivalent HPV (qHPV) vaccines in girls and women 16-26 years of age, showed that the 9vHPV vaccine was generally well tolerated. Additional safety analyses were conducted to include the results of new clinical studies. The safety profile of the 9vHPV vaccine in prior qHPV vaccine recipients (n = 3756 from 1 randomized controlled trial and 2 open-label extension studies) and young men (n = 248 9vHPV and n = 248 qHPV vaccine recipients from 1 randomized controlled trial) was evaluated. Vaccine was administered as a 3-dose regimen (at Day 1 and Months 2 and 6), and adverse events (AEs) were monitored. The most common AEs were injection-site events (91.1% and 79.0% in prior qHPV vaccine recipients and young men, respectively), the majority of which were mild. Discontinuations due to an AE were rare (0.2% and 0.0% among prior qHPV vaccine recipients and young men, respectively). In young men, the AE profile of the 9vHPV vaccine was generally similar to that of the qHPV vaccine. Overall, the 9vHPV vaccine was generally well tolerated in prior qHPV vaccine recipients and in young men, with an AE profile generally consistent with that previously reported with the broader clinical program.

Immunogenicity and safety of the 9-valent HPV vaccine in men.

OBJECTIVES: This study was designed to evaluate the immunogenicity and tolerability of a prophylactic 9-valent HPV (types 6/11/16/18/31/33/45/52/58) VLP (9vHPV) vaccine in young men 16-26 years of age in comparison to young women 16-26 years of age (the population that was used to establish 9vHPV vaccine efficacy). Safety and immunogenicity data from this study will be used to bridge 9vHPV vaccine efficacy findings in 16-26 year old women to 16-26 year old men. METHODS: This study enrolled 1106 heterosexual men (HM) and 1101 women who had not yet received HPV vaccination. In addition, 313 men having sex with men (MSM) were enrolled and were evaluated separately for immunogenicity because previous results showed that antibody responses to quadrivalent HPV (types 6/11/16/18) VLP (qHPV) vaccine were lower in MSM than in HM. All subjects were administered a 3-dose regimen (Day 1, Month 2, Month 6) of 9vHPV vaccine. Serum samples were collected for anti-HPV assays. Safety information was collected for ∼ 12 months. RESULTS: The geometric mean titers (GMTs) for HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58 for HM were non-inferior to those of women at Month 7. For all vaccine HPV types, Month 7 GMTs were numerically lower in MSM than in HM. Over 99.5% of subjects were seropositive at Month 7 for each vaccine HPV type. Administration of 9vHPV vaccine to both 16-26 year old men and women was generally well tolerated. CONCLUSIONS: These results support bridging the efficacy findings with 9vHPV vaccine in young women 16-26 years of age to men 16-26 years of age.

Electroporation-based DNA transfer enhances gene expression and immune responses to DNA vaccines in cattle.

Despite the potential of DNA vaccines to induce strong, balanced immune responses in small experimental species, the immune responses to DNA immunization in larger species have generally been moderate and inconsistent. In this study, the TriGridtrade mark Delivery System (TDS), an electroporation-based DNA delivery platform, was evaluated for administration of DNA vaccines to calves. When compared to conventional intramuscular delivery, TDS-based delivery markedly and consistently enhanced gene expression from a plasmid encoding a reporter gene, secreted alkaline phosphatase, and improved cell-mediated and humoral immune responses to a plasmid encoding a model antigen, hepatitis B surface antigen. Importantly, the TDS-based procedure was well tolerated by the calves, which did not need to be anesthetized or sedated. These results suggest that the TDS is a useful delivery method for DNA vaccines in cattle.

Potentiation of an anthrax DNA vaccine with electroporation.

DNA vaccines are a promising method of immunization against biothreats and emerging infections because they are relatively easy to design, manufacture, store and distribute. However, immunization with DNA vaccines using conventional delivery methods often fails to induce consistent, robust immune responses, especially in species larger than the mouse. Intramuscular (i.m.) delivery of a plasmid encoding anthrax toxin protective antigen (PA) using electroporation (EP), a potent DNA delivery method, rapidly induced anti-PA IgG and toxin neutralizing antibodies within 2 weeks following a single immunization in multiple experimental species. The delivery procedure is particularly dose efficient and thus favorable for achieving target levels of response following vaccine administration in humans. These results suggest that EP may be a valuable platform technology for the delivery of DNA vaccines against anthrax and other biothreat agents.

Enhancement of immune responses to an HBV DNA vaccine by electroporation.

These studies document the ability of electroporation (EP)-based DNA vaccination to induce multi-specific CTL responses to hepatitis B virus (HBV) DNA vaccination in normal mice and marked immune responses to multivalent HBV DNA immunization in larger animal species. These results suggest that electroporation-mediated HBV DNA vaccination is worth pursuing as a treatment for chronic HBV infection.

Probing the activation requirements for naive CD8+ T cells with Drosophila cell transfectants as antigen presenting cells.

Activation of T cells involves multiple receptor-ligand interactions between T cells and antigen presenting cells (APC). At least two signals are required for T-cell activation: Signal 1 results from recognition of MHC/peptide complexes on the APC by cell surface T-cell receptors (TCR), whereas Signal 2 is induced by the interactions of co-stimulatory molecules on APC with their complementary receptors on T cells. This review focuses on our attempts to understand these various signals in a model system involving the 2C TCR. The structural basis of Signal 1 was investigated by determining the crystal structure of 2C TCR alone and in complex with MHC/peptide. Analysis of these structures has provided some basic rules for how TCR and MHC/peptide interact; however, the critical question of how this interaction transduces Signal 1 to T cells remains unclear. The effects of Signal 1 and Signal 2 on T-cell activation were examined with naive T cells from the 2C TCR transgenic mice, defined peptides as antigen and transfected Drosophila cells as APC. The results suggest that, except under extreme conditions, Signal 1 alone is unable to activate naive CD8 T cells despite the induction of marked TCR downregulation. Either B7 or intercellular adhesion molecule (ICAM)-1 can provide the second signal for CD8 T-cell activation. However, especially at low MHC/peptide densities, optimal activation and differentiation of CD8 T cells required interaction with both B7 and ICAM-1 on the same APC. Thus, the data suggest that at least two qualitatively different co-stimulation signals are required for full activation of CD8 T cells under physiological conditions.

Requirements for stimulating naive CD8+ T cells via signal 1 alone.

In the absence of costimulation, TCR recognition of peptide/MHC complexes is generally considered to be nonimmunogenic. In agreement with this view, naive TCR transgenic CD8+ cells failed to respond to specific peptides presented by MHC class I (Ld) molecules bound to mouse RBC. However, peptide/Ld complexes presented by cell-sized beads or bound to plastic led to overt proliferative responses in the absence of added cytokines. Significantly, equivalent strong proliferative responses occurred when mouse RBC were fixed with glutaraldehyde before Ld coupling. The implication therefore is that the intensity of signaling via the TCR is a reflection of the mobility of the ligand being recognized; TCR signaling is weak when the ligand can move laterally on the cell membrane but strong when the ligand is immobilized.

Biomagnetic isolation of antigen-specific CD8+ T cells usable in immunotherapy.

Isolating antigen-specific T lymphocytes is hampered by the low frequency of the cells and the low affinity between T-cell receptors (TCR) and antigen. We describe the isolation and purification of antigen-specific CD8+ T lymphocytes from mixed T-cell populations. Magnetic beads coated with major histocompatibility complex class I molecules loaded with specific peptide were used as a substrate for T-cell capture. Low-frequency T cells, as well as T cells with TCR of low affinity for the antigen were captured on the beads. Following isolation and expansion, recovered cells specifically killed target cells in vitro, and displayed antiviral effect in vivo.

Epstein-Barr virus binding to CD21, the virus receptor, activates resting B cells via an intracellular pathway that is linked to B cell infection.

Epstein-Barr virus (EBV) initiates infection of normal B lymphocytes by binding to CD21, a complement receptor. Since EBV, unlike most viruses, preferentially infects resting (non-activated) cells, the present studies were undertaken to evaluate the hypothesis that intracellular signalling pathway(s) triggered by EBV binding to CD21 activate the expression of certain cellular genes, as well as the initially expressed viral genes, and thus enable EBV to infect resting B cells. Experiments with nontransforming EBV, recombinant virus ligand and anti-CD2 1 MAbs show that EBV binding to CD21 on resting B cells increases CD23 mRNA levels independently of viral gene expression. A panel of five protein kinase C (PKC) and tyrosine kinase (PTK) inhibitors, all with different modes of action, exhibited a distinctive pattern of effects on the EBV induced induction of CD23 expression, ranging from nearly complete inhibition to no influence. The results suggest that distinct PKC isoforms and PTKs are involved in the signalling pathway(s) triggered by EBV binding to CD21. Significantly, the five inhibitors showed the same pattern of effects on the earliest stages of infection (EBNA-2 transcription) and B cell transformation (mitogenesis and colony formation). The identical pattern of effects of these PKC and PTK inhibitors with diverse mechanisms of action on the EBV induced increase in both CD23 and EBNA-2 mRNA levels strongly suggests that their transcription is mediated by an intracellular signalling pathway which shares, at least in part, common members.

Anti-peptide monoclonal antibodies to the beta-adrenergic receptor: use in purification of beta receptor.

This article describes a new immunopurification procedure based on monoclonal antibodies raised against peptides of the carboxy-terminal region of the turkey beta-adrenergic receptor. This procedure constitutes a significant purification step of recombinant beta-adrenergic receptors expressed in baculovirus-infected Sf9 cells, and allows the recovery of receptors able to activate Gs in phospholipid vesicles. Additionally, this procedure can be combined with affinity chromatography to yield nearly homogeneous receptor.

Modulation of signaling via the B cell antigen receptor by CD21, the receptor for C3dg and EBV.

CD21 is the receptor for C3dg and EBV. Several reports have shown that these CD21 ligands, and certain anti-CD21 mAb, trigger B cell activation, particularly when combined with Ag receptor ligation. However, the characteristics, biologic functions, and importance of this CD21-signaling pathway are unknown. We have used a model we recently developed to study B cell activation induced by complex particulate Ag, such as immune complexes and viruses, to begin to examine these questions. In the current studies, we incubated purified small resting B cells with 100-nm latex beads bearing various combinations of CD21 ligands and mAbs to CD19, CD35, and the Ag receptor. CD21, CD19, and CD35 have all been implicated in modulating membrane IgM initiated signaling. Beads coated with mAb to the C3dg/EBV-binding portion of CD21, but not mAb to other portions of the CD21 molecule, triggered B cell homotypic aggregation. Beads coated with the same CD21 ligands, although inactive alone, synergized with anti-IgM mAb in greatly increasing (20- to 180-fold) mRNA levels of the c-fos nuclear proto-oncogene. Signaling via CD21 was tyrosine kinase dependent. Levels of c-myc mRNA were not altered by CD21 ligands. Anti-CD19 and anti-CD35 mAb did not augment signaling via membrane IgM as assessed by changes in c-fos mRNA levels. These findings indicate that CD21 ligands binding to the C3dg/EBV-binding site of CD21 markedly augment B cell activation initiated by Ag receptor ligation via a selective, c-fos-dependent signaling pathway.

T cell-dependent, B cell-activating properties of antibody-coated small latex beads. A new model for B cell activation.

We have developed a new model to study B cell activation induced by complex particulate Ag, immune complexes, and viruses. As the surrogate for such Ag, we have used 100-nm fluorescent latex beads bearing mAb to IgM and IgD. Anti-IgM- and anti-IgD-coated small latex beads bind readily to tonsil resting B cells and induce homotypic B cell aggregation. Aggregation induced by anti-IgM-coated beads but not by anti-IgD-coated beads was massively enhanced by IL-2 and IL-4. Anti-IgM- and anti-IgD-coated beads increased (4- to 12-fold) c-fos and c-myc mRNA levels in resting B cells in a dose-dependent manner; this increase was tyrosine kinase dependent. Anti-IgM- and anti-IgD-coated beads were mitogenic for resting B cells, but unlike other B cell activation models, mitogenesis was absolutely dependent on the presence of IL-2 or IL-4. Finally, anti-IgM-coated beads but not anti-IgD-coated beads were internalized as single beads into small, thin-walled endocytic vesicles; internalization was absolutely dependent on the presence of IL-4. Binding and internalization can be readily quantified because the beads are fluorescent. This model can also be used to study the functions of other cell surface molecules that modulate Ag-specific B cell immune responses. It will also be used for examining multiple aspects of T-B cell interactions during immune responses and Ag processing because of the dependence on T cell factors for B cell activation, coupled with the finding that the Ab-coated beads are internalized.

Immunologic mapping of the amino- and carboxy-termini of the turkey erythrocyte beta-adrenergic receptor: selective proteolysis of both domains.

Peptide-directed antibodies were used to map the N- and C-termini of the turkey erythrocyte beta-adrenergic receptor, the full length recombinant receptor expressed in Sf9 cells, and a mutant that terminates after residue 424 (T424). Both forms of the natural receptor (P40 and P50) were proteolytically clipped between residues 419 and 424. P40, but not P50, is also proteolyzed between residues 14 and 28. Truncation mutants, but not full length receptors, also display both large and small forms. The short form of T424 is formed by proteolysis after residue 14, but neither form is proteolyzed in the C-terminal region. The wild type recombinant receptor is not proteolyzed.

High concentrations of 2-5A, the interferon intracellular mediator, in the blood of children with acute viral infections.

We measured the concentration of 2-5A (2',5'-oligoadenylate), an intracellular mediator of the antiviral action of interferon, in the blood of children with acute viral and bacterial infectious diseases. 2-5A concentration was found to be elevated in several children with viral diseases. This elevation seemed transient and was not specific for viral infections. We provide arguments for the use of 2-5A as a marker of the evolution of diagnosed viral diseases.

Establishment and characterization of mouse thymic epithelial cell lines.

Primary stromal cell cultures from fetal day-16 thymuses of Swiss mice were developed using a combination of D-valine-containing DMEM and Ham's F-12 medium supplemented with epidermal growth factor, insulin and cortisone. Using cloning cylinders and subsequent limiting dilution techniques, we obtained two clones, MTE-1 and MTE-2. The presence of cytokeratin filaments established their epithelial origin. These cells expressed class I and class II MHC antigens after induction by gamma-interferon, and lacked conventional lymphoid cell-surface markers. Their ability to form rosettes with thymocytes should allow us to identify cell-surface antigens involved in thymocyte-epithelial cell interaction. Moreover, these lines will be used to set up in vitro thymocyte maturation assays.

Intracellular metabolism of the interferon mediator, 2-5A, using permeabilized cells.

2-5A synthetase and 2'-phosphodiesterase, the enzymatic activities which respectively synthesize and degrade the interferon mediator 2-5A (ppp(A2'p)nA), were studied in digitonin-permeabilized cells. 2-5A synthetase was higher in permeabilized than in lysed Daudi cells. Mouse L cells appeared to contain two different 2-5A synthetase activities, one of which could be separated from 2'-phosphodiesterase activity, which was only cytosolic. Permeabilization techniques offer opportunities to investigate (2',5')-oligoadenylate intracellular metabolism, which remains incompletely known.

Do viruses play an etiologic role in ankylosing spondylitis or psoriatic arthritis?

High venous blood levels of 2-5A, an adenylic acid polymer synthesized in the presence of double-stranded RNA and considered as a viral replication indicator, have been found in blood samples from ankylosing spondylitis and psoriatic arthritis patients, but not from patients with seropositive rheumatoid arthritis or acute chondrocalcinosis. These findings suggest the possibility that ankylosing spondylitis and psoriatic arthritis might be virus-induced diseases.

Enzyme immunoassay of 2'-5'-oligoadenylates at the femtomole level.

We have developed a competition enzyme immunoassay (EIA) for 2'-5'-oligoadenylates [p kappa(A2'p5')nA; 0 less than or equal to kappa less than or equal to 3; 1 less than or equal to n] based on an anti-A2'p5' A monoclonal antibody coated onto 96-well polystyrene plates and A2'p5' A peroxidase as a marker. It permits measurement of 5'OH(A2'p5')nA as such and p kappa(A2'p5')nA after alkaline phosphatase hydrolysis, with a detection threshold of 5 X 10(-12) M. All 2'-5'-oligomers were assayed with similar sensitivity. ATP and adenosine did not interfere at concentrations up to 10(6)-fold higher than those of 2'-5'-oligoadenylates. Reproducibility, stability of reagents and correlation with the radioimmunoassay were good. As such, this EIA is a suitable tool for studying the 2-5A system, particularly, in clinical investigations: the initial velocity of 2-5A synthetase can be determined on 10,000 cells without purification and the level of 2'-5'-oligoadenylates can be assayed on less than 1 ml of blood.