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BACKGROUND Influenza-virus hemagglutinin (HA) protein expressed in insect cells by recombinant baculovirus is a candidate influenza vaccine. METHODS In a randomized, double-blind trial conducted in 399 adults > or = 65 years of age, the efficacy of trivalent inactivated influenza vaccine (TIV) licensed for intramuscular injection was compared with that of trivalent baculovirus-expressed HA vaccine administered at doses of 15 microg, 45 microg, or 135 microg of each HA. RESULTS Compared with TIV, baculovirus-expressed HA vaccine was safe and induced better serum antibody responses to the H3 component when administered at doses of 45 microg or 135 microg of each HA. CONCLUSIONS Baculovirus-expressed HA is a safe and immunogenic influenza vaccine in elderly adults.

Presentation of Case A 38-year-old schizophrenic man was admitted to the hospital because of digital clubbing and a cardiac murmur. The patient had been well until about one year earlier, when he began to have swelling of the fingers and toes. Eleven months before admission, an evaluation elsewhere showed a grade 2 systolic murmur at the lower left sternal border. One month before admission, he underwent a dental extraction and took ampicillin prophylactically for two days. On the day of admission, examination of the patient in the medical clinic revealed two loud murmurs. A cardiac ultrasonographic examination showed severe mitral . . .

Video-enhanced microscopy was used to examine the interaction of elastin- or laminin-coated gold particles with elastin binding proteins on the surface of live cells. By visualizing the binding events in real time, it was possible to determine the specificity and avidity of ligand binding as well as to analyze the motion of the receptor-ligand complex in the plane of the plasma membrane. Although it was difficult to interpret the rates of binding and release rigorously because of the possibility for multiple interactions between particles and the cell surface, relative changes in binding have revealed important aspects of the regulation of affinity of ligand-receptor interaction in situ. Both elastin and laminin were found to compete for binding to the cell surface and lactose dramatically decreased the affinity of the receptor(s) for both elastin and laminin. These findings were supported by in vitro studies of the detergent-solubilized receptor. Further, immobilization of the ligand-receptor complexes through binding to the cytoskeleton dramatically decreased the ability of bound particles to leave the receptor. The changes in the kinetics of ligand-coated gold binding to living cells suggest that both laminin and elastin binding is inhibited by lactose and that attachment of receptor to the cytoskeleton increases its affinity for the ligand.

ContextA high priority in vaccine research is the development of influenza vaccines that do not use embryonated eggs as the substrate for vaccine production.ObjectiveTo determine the dose-related safety, immunogenicity, and protective efficacy of an experimental trivalent influenza virus hemagglutinin (rHA0) vaccine produced in insect cells using recombinant baculoviruses.Design, Setting, and ParticipantsRandomized, double-blind, placebo-controlled clinical trial at 3 US academic medical centers during the 2004-2005 influenza season among 460 healthy adults without high-risk indications for influenza vaccine.InterventionsParticipants were randomly assigned to receive a single injection of saline placebo (n = 154); 75 μg of an rHA0 vaccine containing 15 μg of hemagglutinin from influenza A/New Caledonia/20/99(H1N1) and influenza B/Jiangsu/10/03 virus and 45 μg of hemagglutinin from influenza A/Wyoming/3/03(H3N2) virus (n = 153); or 135 μg of rHA0 containing 45 μg of hemagglutinin each from all 3 components (n = 153). Serum samples were taken before and 30 days following immunization.Main Outcome MeasuresPrimary safety end points were the rates and severity of solicited and unsolicited adverse events. Primary immunogenicity end points were the rates of 4-fold or greater increases in serum hemagglutinin inhibition antibody to each of the 3 vaccine strains before and 28 days after inoculation. The prespecified primary efficacy end point was culture-documented influenza illness, defined as development of influenza-like illness associated with influenza virus on a nasopharyngeal swab.ResultsRates of local and systemic adverse effects were low, and the rates of systemic adverse effects were not different in either vaccine group than in the placebo group. Hemagglutinin inhibition antibody responses to the H1 component were seen in 3% of placebo, 51% of 75-μg vaccine, and 67% of 135-μg vaccine recipients, while responses to B were seen in 4% of placebo, 65% of 75-μg vaccine, and 92% of 135-μg vaccine recipients. Responses to the H3 component occurred in 11% of placebo, 81% of 75-μg vaccine, and 77% of 135-μg vaccine recipients. Influenza infections in the study population were due to influenza B and A(H3N2), and influenza A infections were A/California/7/2004–like viruses, an antigenically drifted strain. Seven cases of culture-confirmed CDC-defined influenza-like illness occurred in 153 placebo recipients (4.6%) compared with 2 cases (1.3%) in 150 recipients of 75 μg of vaccine, and 0 cases in recipients of 135 μg of vaccine.ConclusionsIn this study, a trivalent rHA0 vaccine was safe and immunogenic in a healthy adult population. Preliminary evidence of protection against a drifted influenza A(H3N2) virus was obtained, but the sample size was small. Inclusion of a neuraminidase component did not appear to be required for protection.Trial Registrationclinicaltrials.gov Identifier: NCT00328107