An Haemophilus influenzae type b capsular polysaccharide-protein conjugate has been prepared. The polysaccharide was coupled to the serotype II protein of group B meningococcus through the spacer 6-aminocaproic acid using cyanogen bromide and water soluble carbodiimide. The conjugate can be shown to be reproducible and is stable and highly immunogenic in mice and African green monkeys. Clinical evaluation of this conjugate in children 3 months to 4 years of age showed that it elicited an antibody titer to the polysaccharide moiety greater than 1000 ng/ml in children 8 months of age or older.

A clinical trial among 137 healthy children, ages 1 to 12 years, was conducted with four different doses (4,350, 870, 435, and 43 plaque-forming units [pfu]) of live Oka/Merck varicella vaccine to evaluate clinical reactions and selected laboratory parameters and to determine the minimum effective dose and induction time of antibody. The vaccine was well tolerated with no significant difference in the rate of reported symptoms by dose. The frequency of varicellalike rash was 3% (4/137); all rashes were mild. Serum aminotransferase values were essentially unchanged after vaccination. Minor variations found in platelet counts after vaccination were not associated with any bleeding, bruising, or clotting. Among initially seronegative children who received doses of 435 pfu or greater, 94% assayed at two weeks and 100% assayed at four or six weeks seroconverted. The geometric mean titers were similar for all four doses at six weeks. IgG and IgA responses were demonstrated with no relation to the vaccine dose.

Journal Article Responses of Adult Volunteers to a Pseudomonas aeruginosa Exotoxoid-A Vaccine Get access Eva Lydick, Eva Lydick Departments of Virus and Cell Biology, Merck Sharp and Dohme Research Laboratories, West Point, Pennsylvania Search for other works by this author on: Oxford Academic PubMed Google Scholar Arlene A. Mclean, Arlene A. Mclean Departments of Virus and Cell Biology, Merck Sharp and Dohme Research Laboratories, West Point, Pennsylvania Search for other works by this author on: Oxford Academic PubMed Google Scholar Allen F. Woodhour, Allen F. Woodhour Departments of Virus and Cell Biology, Merck Sharp and Dohme Research Laboratories, West Point, Pennsylvania Search for other works by this author on: Oxford Academic PubMed Google Scholar Lynn T. Callahan, III Lynn T. Callahan, III Departments of Virus and Cell Biology, Merck Sharp and Dohme Research Laboratories, West Point, Pennsylvania Search for other works by this author on: Oxford Academic PubMed Google Scholar The Journal of Infectious Diseases, Volume 151, Issue 2, February 1985, Page 375, https://doi.org/10.1093/infdis/151.2.375 Published: 01 February 1985

A vaccine formulated from hepatitis B surface antigen (HBsAg) produced by a recombinant strain of the yeast Saccharomyces cerevisiae was administered to two groups of human volunteers composed of 37 healthy, low-risk adults. Each subject received a 10-micrograms dose of HBsAg at 0, 1, and 6 months. By one month, 27% to 40% of the vaccinees had antibody to HBsAg, and by three months 80% to 100% were antibody positive. Large boosts in titer followed the third dose at six months. The antibody formed is predominantly specific for the a determinant of HBsAg. There have been no serious reactions attributable to the vaccine. The most frequent complaint has been transient soreness at the injection site. As far as we know, this is the first reported use in man of a vaccine prepared by recombinant DNA technology.

Vaccine against human hepatitis B was prepared using antigen derived from hepatitis B carrier hepatoma cells grown in the interstices of a Diaflo hollow filter unit. Hepatitis B surface antigen (HBsAg) produced by these cells was purified by immune affinity chromatography, digestion with DNase and pepsin, and Sephadex G-150 separation. The Formalin-treated antigen was formulated in 20-micrograms dose on alum adjuvant with thimerosal added as a preservative. This cell culture vaccine was as potent as human plasma-derived vaccine as measured in a mouse potency assay. The vaccine proved safe in tests in chimpanzees and in human subjects who were in late stages of cancer of the central nervous system and who were receiving therapy for their condition. None of five subjects who received the vaccine developed untoward clinical reactions. Two of the subjects who received all three doses of vaccine developed antibody against HBsAg. Three persons, two given only the primary doses and one who was given all three doses but was lost to follow-up, demonstrated no response. The slow and relatively low antibody responses to the vaccine were similar to those in other immunosuppressed persons who were given vaccine of human plasma origin.

A live measles virus vaccine that is highly temperature-stable and dispensed in an inexpensive syringe is described. This configuration should prove useful for programs aimed at mass immunization against measles.

Preparation of hepatitis B vaccine in our laboratories consists of a series of steps that include initial concentration of surface antigen by ammonium sulfate precipitation, followed by isopycnic banding and rate zonal centrifugation in a K-II centrifuge. The partially purified antigen concentrate is digested with pepsin at pH2 and the antigen is unfolded in 8M urea solution followed by renaturation. After gel filtration, the antigen is treated with formalin in 1:4000 dilution, adsorbed onto alum, and preserved with thimerosal. The final product contains essentially pure hepatitis B surface antigen. The process relies both on physical elimination of infectious virus particles and treatment with highly viral-destructive reagents in the pepsin, urea and formalin steps. The process is known to be highly destructive of all known viruses tested and to include procedures that are known to be highly destructive of representatives of all known groups of animal viral agents. The three-step process in inactivation provides a fail-safe system for establishing safety of the product. Tests in more than 20'000 persons, who are under surveillance, have shown no untoward effect and have confirmed the safety of the product.

The hepatitis B vaccine produced by MSD consists of highly purified HBsAg which is adsorbed on to aluminium hydroxide adjuvant. The vaccine produces an anti-HBs response in 90 per cent or more of healthy infants, children and adults who receive the recommended three-dose regimen. These antibodies persist for at least 36 months in most individuals studied. Age is the major factor determining responsiveness to the vaccine. Children show a brisk, high-level response and require only 10 μg of HBsAg per dose. Younger adults also respond rapidly to 20 μg doses of HBsAg. Older adults, especially those over 60, may show a sluggish response. Immunocompromised individuals, such as renal dialysis patients, also show reduced responsiveness to the vaccine.

Preparation of hepatitis B vaccine in our laboratories consists of a series of steps that include initial concentration of surface antigen by ammonium sulphate precipitation, followed by isopycnic banding and rate zonal centrifugation in a K-II centrifuge. The partially purified antigen concentrate is digested with pepsin at pH 2 and the antigen is unfolded in 8 M urea solution followed by renaturation. After gel filtration, the antigen is treated with formalin in I :4000 dilution, adsorbed on to alum, and preserved with thimerosal. The final product contains essentially pure hepatitis B surface antigen. The process relies both on physical elimination of infectious virus particles and treatment with highly viral-destructive reagents in the pepsin (pH 2), urea and formalin steps. The process is known to be highly destructive of all known viruses tested and to include procedures that are known to be highly destructive of representatives of all known groups of animal viral agents. The three-step process in inactivation provides a fail-safe system for establishing safety of the product. Tests in more than 20000 persons, who are under surveillance, have shown no untoward effect and have confirmed the safety of the product.

The sensitivity of an enzyme-linked immunosorbent assay (ELISA) to detect low levels of antibody to respiratory syncytial (RS) virus was compared with a tube dilution neutralization test (NEUT) on sera obtained from children who received a parenteral live RS virus vaccine. Among the children who developed antibody in response to live RS virus vaccine. ELISA was as sensitive as NEUT at detecting antibody increases. Some children who did not have detectable prevaccine ELISA antibody possessed NEUT antibody; these children were generally less than 12 months old, suggesting that they had low levels of maternal antibody. Low levels of NEUT or ELISA antibody were associated with the absence of antibody increases after injection of live RS virus vaccine. The quantity of antibody stimulated by this live RS virus vaccine was small compared with that which was stimulated by naturally acquired RS virus infection. We concluded that ELISA is a satisfactory test for determining antibody to RS virus in vaccine field trials, given the understanding that low levels of preexisting antibody are not detected in some instances.

A single-dose, low-cost vaccine delivery system (Ezeject®) consisting of lyophilized measles (Moraten—Attenuvax®) vaccine loaded into a pre-filled single-dose plastic syringe with a squeezable body portion has been developed in these laboratories. Data concerning the preparation and properties of vaccine-filled plastic syringes and the findings in clinical tests are presented in this report.

Contemporary 14-valent pneumococcal polysaccharide vaccine was first licensed in 1977 in the United States, where about four million doses of vaccine have been distributed to date. The vaccine induces excellent antibody responses in elderly persons as well as in young adults. The antigen content of the vaccine is 50 microgram of each serotype of polysaccharide per dose, and lower titers of antibody are induced when the dose is reduced to 25 or 12.5 microgram of antigen. Adverse reactions are usually mild and consist principally of local erythema and induration at the injection site, with mild fever in a small proportion of subjects. Antibody persists well for at least four years, and it is expected that immunity will last for at least 5 years after vaccination. Local and systemic reactions to the vaccine may be greater when a second dose of vaccine is administered within three years after the initial dose, and this reactivity appears to be due to a Arthus-like response that results from local formation of antigen-antibody complexes. Pneumococcal and influenza vaccines can be injected simultaneously into separate sites without impairment of antibody responses to either vaccine; this feature should facilitate administration of these two vaccines.

Eleven lots of combined bivalent and trivalent vaccines containing the measles (Moraten), mumps (Jeryl Lynn), and rubella (RA 2713) viruses gave satisfactory results in tests in initially seronegative children (measles, 493 children; mumps, 377; rubella, 586). There was no apparent suppression of antibody response against any of the viruses in the vaccines. The clinical reactions observed were mild and inconsequential. Substitution of the HPV 77-DE strain employed heretofore with the RA 27/3 is technically acceptable and offers the advantage of higher titer, slightly greater seroconversion rate, and more solid immunity against reinfection in nature.

Dried live measles, mumps and rubella virus vaccines prepared in a new stabilizing medium were tested for loss of potency, according to time, at a range of temperatures from −20°C to 54–56°C. All vaccines proved remarkably stable and predictive values for retention of adequate potency for periods of time at a range of temperatures are presented. The quality of the current vaccine should go far toward assuring potency under adverse conditions of handling in developed countries and in handling outside the cold chain in emerging parts of the world.

Adult persons who were given a pneumococcal polysaccharide vaccine containing 50 μg each of 12 serotypes showed an average 10-fold increase in amount of antibody to the 12 antigens (range 6- to 20-fold) 1 month after vaccination and there was an approximate average 50% decline in antibody 31/2 years later. Children who were 2 to 12 years old at the time of vaccination showed about the same antibody response to the vaccine but this was less persistent and there was about a 55% decline, on the average, after only 21 months, The findings are discussed in the light of need for revaccination and of the nature of antibody responses to polysaccharide antigens.

Antibody persistence was measured in children in the open community 10.5 years after combined measles-mumps-rubella (14 children), 9 years after measles-rubella (17 children), 10.5 years after mumps-rubella (9 children), and 7 years after measles-mumps (20 children) vaccines were given. There were increases, declines, and stationary titers among the children in the serum samples taken 6 weeks after vaccination compared with those taken at later time periods. This reflected a decline in antibody in some children and subclinical natural reinfection in others. Importantly, all the children still retained detectable antibody, indicating long-term persistence of immunity by vaccination with combined virus vaccines.

Comparative studies of RA 27/3 and HPV 77-DE rubella virus vaccines were carried out in children and adults. RA 27/3 vaccine induced antibody in a larger proportion of individuals and at a substantially higher titer level than did HPV 77-DE vaccine. Additionally, the RA 27/3 vaccine induced theta and iota antibodies that are commonly found after infection with rubella virus in nature. The greater serologic responses to RA 27/3 virus were achieved without any important increase in clinical reactions and there was no evidence for contagious spread of the infection. There was slightly greater occurrence of rash and lymphadenopathy after RA 27/3 vaccine compared with HPV 77-DE but the rate for occurrence of arthritis was substantially lower. Nearly 8000 initially seronegative persons received the RA 27/3 vaccine in the present studies. The seroconversion rate was 98% and there were no clinical reactions of importance. Follow-up studies showed undiminished retention of antibody titer for at least 2 years following vaccination with RA 27/3 vaccine.

Further clinical tests were carried out of a live attenuated respiratory syncytial virus vaccine administered parenterally. Neutralization of respiratory syncytial virus by homologous human antibody was found to be a complement-dependent event and addition of guinea pig complement greatly increased antibody titers and the sensitivity of the test. Ninety-seven percent of 116 initially seronegative children developed antibody following vaccination and there was no evidence for contagious spread of the infection. Clinical reactions, if any, were mild and inconsequential. A small portion of initially seropositive persons appeared to develop antibody by booster effect and a portion of initially seronegative and seropositive persons developed detectable nasal antibody. Long-term follow-up failed to reveal any increase in severe respiratory disease in initially seronegative persons who were vaccinated. A very substantial reservoir of seronegative persons was found in the 7 to 47 month age group (35%) revealing a target population that could most benefit from being given the vaccine.

Hemagglutination-inhibiting antibodies were present at comparable levels 10 years after vaccination with Enders'original Edmonston and more attenuated Moraten (Attenuvax) and Schwarz line measles vaccines. There was no substantial decline in neutralizing antibody titer for nearly 12 years after administration of Jeryl Lynn strain mumps virus vaccine (Mumpsvax). Hemagglutination-inhibiting antibodies were present without important decline in amount for at least 9.5 and 9 years, respectively, in children and adult women after administration of HPV-77 duck cell modified rubella vaccine (Meruvax). Higher homologous antibody titers were achieved initially following less attenuated Enders'Edmonston measles vaccine compared with more attenuated Moraten line vaccine and following natural mumps compared with mumps vaccine. Approximately 10 years later, however, the mean titers were roughly the same in each instance, indicating no apparent advantage of more virulent vaccine virus or natural infection in providing immunity. In our opinion, the relatively small number of purported measles virus vaccination failures reported in recent years were due mostly to mishandling or misadministration of the vaccine and not to deficiencies in measles vaccine itself.