Showing papers on "Viral Vaccine published in 1976"

Cell-mediated immunity to respiratory syncytial virus induced by inactivated vaccine or by infection.

Abstract: Transformation and increased mitotic activity in donor lymphocytes exposed to specific antigens is considered by many to be a manifestation of cell-mediated immunity. In attempts to understand the apparent "sensitization" of individuals to respiratory syncytial virus (RSV) as a result of receiving inactivated RSV vaccine, in vitro lymphocyte transformation studies were carried out on infants who had received inactivated RSV vaccine and on infants who had received a similarly prepared inactivated African green monkey kidney (AGMK) cell-grown parainfluenza type 1 virus vaccine or a trivalent parainfluenza vaccine prepared in hen's eggs. Each group included some infants who had, and others who had not, undergone natural RSV infection under our observation before the lymphocyte studies. Lymphocytes were studied from 21 infants and young children who had received the inactivated RSV vaccine, 14 who had received a similarly prepared inactivated parainfluenza 1 vaccine, and 5 who received a trivalent parainfluenza vaccine. Twelve of the RSV vaccinees and 14 of the parainfluenza vaccinees had been naturally infected with RSV as indicated by virus recovery and/or antibody rise between the time of vaccination and the lymphocyte studies. In comparing the arithmetic mean for RSV-specific transformation and mitotic activity there was a significant difference between RSV vaccinees and parainfluenza vaccinees whether one compared those who had undergone natural RSV infection or those who had not undergone natural infection. The difference between RSV vaccinees who had not undergone natural RSV infection and RSV-infected parainfluenza vaccinees also was significant. There was a greater level of transformation and mitotic activity in those who had experienced natural infection than those who had not among both RSV vaccinees and parainfluenza vaccinees, but these differences were not significant statistically.

Fatal vaccine-induced canine distemper virus infection in black-footed ferrets.

Abstract: Four black-footed ferrets that were live-trapped in South Dakota and transported to the Patuxent Wildlife Research Center died within 21 days after vaccination with modified live canine distemper virus. Immunofluorescence, European ferret inoculation, virus isolation attempts, and serum-neutralization tests indicated insufficient attenuation of the vaccine for this species.

Herpes Simplex Vaccines

Abstract: Prospects for the development of vaccines against herpes simplex virus types 1 and 2 and other herpesvirus group vaccines are discussed from the scientific, medical, and economic standpoints. Probably, the most practical development will be glycoprotein subunit vaccines, prepared from herpes simples virus types 1 and 2, that will be tested for prophylaxis and therapy of acute viral disease and for cancer that may be caused by these agents.

Modified polyriboinosinic-polyribocytidylic acid, an immunological adjuvant.

Abstract: Stabilization of polyriboinosinic-polyribocytidylic acid against enzymatic hydrolysis by addition of poly-1-lysine and carboxymethylcellulose (PICLC) resulted in a compound with marked adjuvanticity. The primary antibody response of rhesus monkeys to formalin-inactivated Venezuelan equine encephalomyelitis virus vaccine was significantly potentiated if the vaccine was combined with PICLC prior to vaccination. The antibody response was maintained at a significantly higher level than controls for 2.5 months postvaccination and paralleled immunological responses reported for live, attenuated (TC-83) vaccine.

Suppression of murine type-C RNA virogenes by type-specific oncornavirus vaccines: prospects for prevention of cancer.

Abstract: Immunization of crossbred and F1 mice with combined killed and live Gross leukemia virus AKR type-C viral vaccines suppressed endogeneous N-type AKR virus up to 10,000-fold for significant periods during early life. Since several previous studies in the same and similar crossbred systems revealed direct correlations between low and high levels of type-C virus early in life with low and high incidences of leukemia and other cancers later in life, we believe that prospects for suppression of spontaneous neoplasms are good; however, 8-14 months will be required to achieve the final results. Should cancers be prevented by serotype-specific vaccines, such evidence would provide conclusive proof of endogenous viral etiology.

Familial differences in antibody response of broiler chickens to vaccination with attenuated and inactivated Newcastle disease virus vaccine.

Abstract: Genetic differences in immune response to Newcastle disease virus (NDV) were studied in 4-week-old broilers, vaccinated with attenuated (live) or inactivated NDV. The experiment included 370 chicks from two farms distributed among 22 sire families and 60 dam families. Results in chicks from both farms were similar. Survival after challenge was closely related to titer level. The genetic correlation between day-7 and day-12 titers (attenuated virus) was 1.0. Significant differences were found between sire families in both sorts of vaccinations. Heritabilities based on the sire variance components for attenuated and inactivated virus vaccinations were respectively 0.31 and 0.60. The genetic correlation between them was 0.49. Nevertheless, it is concluded that selection for response to NDV based on inactivated virus may be most effective in improving response to attenuated NDV vaccinations.

Prevention of Marek's Disease: A Review

Abstract: Marek's disease (MD) is a highly infectious neoplastic condition of chickens caused by a herpesvirus. The virus is cell associated in tumors and in all organs except in the feather follicle where enveloped infectious virions egress from the body. From this source, infection is spread horizontally by the airborne route to the environment and to other chickens. Vertical transmission from dam to offspring does not occur or at best is very rare. The nonpathogenic herpesvirus of turkeys (HTV) is ubiquitous in turkeys and is probably spread horizontally by the airborne route. When chickens are inoculated with this virus, they do not subsequently develop MD even after infection with virulent Marek's disease virus. The Marek's disease virus, not the HVT, will spread horizontally from dually infected birds. The HVT vaccine is safe and highly effective in preventing MD under field conditions, and most chickens throughout the world are vaccinated with this vaccine. Other vaccines that have been used but have disadvantages over HVT include the following: (a) the highly pathogenic HPRS 16 strain of Marek's disease virus was attenuated by passage in cell culture. The attenuated virus protects against MD and does not spread, but "over-attenuated" virus does not protect; (b) naturally apathogenic strains virologically, immunologically, and epizootiologically similar to pathogenic strains will protect when adminstered before infection with the virulent strains; (c) virus preparations that have been chemically treated to inactivate infectivity protect only slightly. When a candidate vaccine virus for the prevention of herpesvirus-induced cancer in humans is developed, the purity of the vaccine preparations will be easily determined by modern techniques. However, measurements of safety and effectiveness are a significant problem. If, analogous to the MD model, the vaccine will have to be administered shortly after birth and the incubation period to development of neoplasms is long, then pathogenicity tests in nonhuman primates and other animals may be of limited valued. However, biochemical demonstration that the segment of the nucleic acid responsible for oncogenesis is absent from the vaccine virus may be the major indication that the vaccine is nonocogenic and therefore safe. Because of the low incidence of neoplasia and long incubation period, the effectiveness of the vaccine will be difficult to test. The vaccine possibly will protect against an acute manifestation of viral infection. Future research on MD will be directed to determining the mechanism of protection against disease, i.e., whether immunity is mediated by thymus- or bursa-dependent systems, and to identifying the protective antigen, i.e., which cell surface or an interior antigen induces the protective immunity. The prevention of MD by vaccination may become a very fruitful area for model studies on prevention of human cancer by vaccination.

A canine parainfluenza viral vaccine: immunogenicity and safety.

Abstract: A canine parainfluenza viral vaccine was developed and shown to be safe by absence of clinical disease in vaccinated dogs and by inability to isolate vaccine virus from blood or nasopharyngeal swabs. Backpassage in susceptible dogs, using blood of vaccinated dogs, could not be demonstrated. The vaccine produced neutralizing antibody when administered either intramuscularly or subcutaneously; however, a significantly higher immune response was obtained by intramuscular inoculation. Differences in the antibody response were not produced by tenfold dilutions of vaccine virus ranging from 10(2.9) to 10(5.9) median tissue culture infective doses. The presence of neutralizing antibody was associated significantly with decreased respiratory shedding period of challenge virus by vaccinated dogs compared to seronegative control dogs. Six days after aerosol exposure to virulent challenge virus, 100% of the controls (n = 5) but only 15% of the vaccinated dogs (n = 3) shed virus. Seven days after challenge exposure, virus could not be recovered from the vaccinated dogs, but 80% of the control dogs shed virus. An anamnestic response occurred in vaccinated dogs but not in the seronegative control dogs following challenge exposure. A mild clinical disease was produced in 3 of the 5 seronegative control dogs but not in the 20 vaccinated dogs.

Efficacy of Japanese encephalitis vaccine in horses.

Abstract: The efficacy of Japanese encephalitis vaccine in horses has been described from the effect of mass vaccination on the local prevalence of the disease in horses in each district of Hokkaido, Japan.

Viral hepatitis: overview and historical perspectives.

Abstract: It is a privilege and an honor to be asked to present a general overview and a historical perspective of a subject that has occupied the last 20 years of my medical career. I can assure you that when I accepted this assignment, I did not regard it with a "jaundiced eye." It is particularly appropriate to discuss viral hepatitis with military consultants to the Armed Forces because it is well known that this disease has had a profound effect on military as well as civilian populations throughout the world. During the past three or more centuries "epidemic jaundice" (viral hepatitis, type A) has been recognized as an important military disease, especially during periods of war. Outbreaks were recorded in Germany in 1629 and in the British Army in Flanders in 1743. Epidemics occurred in military and civilian populations at the time of the siege of Paris during the Franco-Prussian war in 1870. Other epidemics occurred during the Boer War in South Africa and in the Japanese Navy during the war with Russia in 1904. This trend continued during the course of all subsequent conflicts: World Wars I and II, the Middle East Wars in 1948, 1956, and 1967, and more recently the Korean and Vietnamese Wars. During the past 50 years the term "epidemic jaundice" referred to a disease that had other names in various parts of the world: jaunice des camps in France, Soldatengelbsucht in Germany, infective hepatitis in England, Botkin's disease in Russia, and acute catarrhal jaundice, epidemic hepatitis, and infectious hepatitis in the United States and other parts of the world. More recently the term proposed by MacCallum in the 1940's, "viral hepatitis, type A," has been adopted. Unlike epidemic jaundice, an ancient disease, serum hepatitis (type B hepatitis) has a more recent history. The first outbreak was described less than 100 years ago by Liirman (1). The occurrence of smallpox in Bremen in 1883 was followed by an extensive vaccination program. The vaccine at that time was prepared from glycerinated lymph of human origin. Of 1289 vaccinated shipyard workers, 191 (15%) developed jaundice after intervals of several weeks to 6 months. In contrast, of 500 unvaccinated new employees, none became jaundiced. In retrospect, it is obvious today that Liirman's report of an epidemic of icterus in 1883 represented the first recognition of an epidemic of viral hepatitis, type B. During the first half of this century it became obvious that epidemics of jaundice were occurring in patients attending venereal disease clinics, diabetic clinics, and tuberculosis clinics, and in children who received inoculations of measles and mumps human convalescent serum, in patients who received blood transfusions, and in

Live, Attenuated Influenza A/England/42/72 (H3N2) Virus Vaccine: A Field Trial

Abstract: Two doses of a live, attentuated influenza A/England/42/72 (H3N2) vaccine virus (inhibitor-insensitive Alice strain) were administered intranasally to 130 university students, and placebo was given to 134 students. Fourfold or greater rises in titer of hemagglutination-inhibiting antibody occurred in 68% of all vaccine recipients and in 88% of those with initial titers of less than 1:8; the geometric mean titer of hemagglutination-inhibiting antibody increased from 1:15 to 1:77. A 3.2-fold rise in titer of neuraminidase-inhibiting antibody occurred in 24% of the students. Side effects produced by administration of the vaccine include mild rhinitis and sore throat, which were found only during the first four days after administration of the first dose. Inhibitor-insensitive virus was shed only by three of 31 intensively studied vaccine recipients; these three subjects all had initial serum titers of hemagglutination-inhibiting antibody of less than 1:8. No transmission of vaccine virus to spouses was detected. During a 12-month interval after vaccination, the geometric mean titer of hemagglutination-inhibiting antibody in serum and the prevalence of antibody decreased minimally among the 47 vaccine recipients still available for study.

Comparisons of cell-free and cell-associated Marek's disease vaccines in maternally immune chicks.

Abstract: Cell-free and cell-associated Marek's disease vaccines prepared from the TK/A isolate of the herpesvirus of turkeys (HVT) were compared to evaluate their relative effectiveness in protecting chicks with homologous maternal antibody. The influence of early challenge on protection was also investigated. Although the higher susceptibility of cell-free HVT to neutralising antibody could be demonstrated in vitro, no significant difference between the two types of vaccine could be established in vivo using chicks with maternal antibody. Chicks exposed to challenge immediately or only a few hours after vaccination were not adequately protected. A higher level of protection was observed when challenge was separated from vaccination by an interval of several days. The importance of proper vaccination procedure, vaccine virus titre and adequate management of vaccinated stock, with particular reference to the risks of early challenge are discussed.

Study design for a hepatitis B vaccine trial.

Abstract: A short-time trial of small sample size for an evaluation of the hepatitis B vaccine is proposed and designed. The vaccine is based on the premise that antibody to the surface antigen of the hepatitis B virus is protective against viral infection. This premise is verified by using the presence of the surface antigen as the marker of infection and comparing infection rates in renal dialysis patients who had naturally acquired antibody to patients without antibody. Patients with antibody have an extremely low risk of infection. The probability of remaining uninfected decreases at an exponential rate for patients without antibody, implying a constant risk of infection at any point in time. The study design described makes use of this time independence and the observed infection rates to formulate a clinical trial which can be accomplished with a relatively small number of patients. This design might be useful if, in preliminary studies, it is shown that the vaccine produces antibody in the patients and that protection against hepatitis B virus would be beneficial to the patients.

Further immunization studies with mammary tumor virus.

Abstract: Summary A single i.m. dose of formalin-inactivated murine mammary tumor virus greatly reduces viral expression and mammary tumorigenesis in Af (tumor incidence, 39%) and RIIIf (tumor incidence, 11%) mice, which carry only endogenous, gamete-transmitted virus. In C57BL mice, 1 µg of vaccine in Freund9s complete adjuvant protects against later challenge with RIII virus.

Evaluation of a virus vaccine in live, attenuated respiratory syncytial

Abstract: Respiratory syncytial virus ts-1 is a live attenuated experimental vaccine which was administered intranasally to 25 infants 11 to 19 months of age. Clinical evaluation was carried out following a controlled, double-blind protocol which eliminated observer bias, assessed intercurrent illness, and was designed to detect virus transmission. At the low dose of virus used (100 TCID~o) 8 of the 25 recipients were successfully infected with RS virus ts-1 as determined by virus shedding or antibody response. Transmission of vaccine virus to the nine control subjects given placebos did not occur. The incidence of illness seen in the vaecinees during the trials was comparable to that of the control subjects. The vaccinated children have been followed through subsequent natural RS virus epidemics. Reinfection has occurred in both vaceinees and control subjects," however, there is no evidence for potentiation of natural illness by the live attenuated RS virus vaccine. The format used in these trials represents one successful prototype for the evaluation of experimental vaccines in children. RESPIRATORY SYNCYTIAL VIRUS is the most common viral agent implicated in bronchiolitis and pneumonia in the infant and young child, a' ~ Considerable effort has been expended toward the development of a safe and effective vaccine for the prevention of clinical illness due to RS virus. The lack of success and the hazards encountered with inactivated RS virus vaccines have directed recent research toward the development of a live, attenuated vaccine that could be administered intranasally. Administration of a respiratory viral vaccine by this route simulates the natural infection and should maximally prime local respiratory tract as well as systemic defense mechanisms. The first such RS virus vaccine was a cold-adapted strain which was shown to be attenuated in adults and then in a stepwise fashion in progressively younger children?. 4 When the cold-adapted strain was administered to seronegative infants mild upper respiratory tract

The immunisation of chickens against infectious avian encephalomyelitis

Abstract: An immune response was induced in chickens vaccinated with the NSW-1 virus by the intramuscular, eye drop, wing web or oral methods. The oral procedure was the most sensitive in inducing an immune response with the lowest dose of virus. The wing web method was the least sensitive. Clinical IAE developed in 1 chicken following intramuscular vaccination. The virus was recovered from the faeces of chickens vaccinated orally with 700 CID50 of the virus from the third to the tenth day after vaccination.

Immunization of broiler chickens with a commercial infectious laryngotracheitis vaccine in the drinking water.

Abstract: Seventy-five thousand broiler chickens in four flocks were immunized at four weeks of age with a commercial infectious laryngotracheitis vaccine administered in the drinking water Three of the flocks exhibited a vaccine reaction represented by mild respiratory illness between seven and 14 days after vaccination Immunity challenge experiments demonstrated 97% protection in one trial and 67% in another trial in which the dose of challenge virus was increased fourfold In the latter trial a parallel comparative vaccination by eye administration was 87% protective None of the vaccinated birds died of the challenge exposure whereas all the unvaccinated control chickens became ill, several showed the acute severe form of the disease and 36% died Similar favourable results were obtained in large-scale water immunization programs involving more than 200,000 birds Serum antibody levels determined before immunity challenge were, within wide limits, inversely related to the severity of clinical disease which developed from the challenge inoculation

Inactivated equine rhinopneumonitis virus vaccine and use thereof

Abstract: An inactivated viral vaccine for protecting horses against disease caused by equine rhinopneumonitis virus is prepared by propagating an equine rhinopneumonitis virus in a susceptible, cloned, diploid equine cell line, harvesting the resulting virus in a serum-free medium, inactivating the virus and neutralizing the inactivating agent, concentrating the virus, and adding an immunological adjuvant thereto. A vaccination program to protect horses against the equine rhinopneumonitis virus is also disclosed.

Safety of Viral Vaccine Cell Substrates: A Reevaluation

Abstract: Primary cultures of African green monkey kidney and rabbit kidney as well as diploid cell lines WI-38 and DBS-FRhL-2 were examined for evidence of tumorigenicity and latent RNA tumor viruses. Cells inoculated into immunosuppressed newborn hamsters and rhesus monkeys were not tumorigenic. Cells treated with 2'-deoxy-5-iodouridine to induce the production of latent viruses were examined by electron microscopy, density gradient centrifugation, and the reverse transcriptase enzyme assay. No evidence was found for RNA tumor viruses by the biochemical or biophysical methods used. The results indicated that each type of mammalian cell currently used in the production of virus vaccines would be acceptable for these parameters of safety if similar control procedures were applied at the time the vaccines were manufactured.

Host Immune Responses after Administration of Inactivated Venezuelan Equine Encephalomyelitis Virus Vaccines. I. Description and Characterization of Adoptive Transfer by Immune Spleen Cells

Abstract: Cellular immune responses after immunization with a number of inactivated Venezuelan equine encephalomyelitis (VEE) virus vaccines were evaluated in mice by means of an adoptive transfer system. Formalin-inactivated, TC-83 strain VEE virus vaccine was immunogenic and highly effective in protecting recipient mice against challenge with virulent VEE virus. In contrast to immunization with live TC-83 VEE virus vaccine, however, immunization with inactivated VEE vaccine did not provide donor mice with the capacity to transfer adoptive immunity readily. Only when mice were immunized with inactivated VEE vaccine combined with specific adjuvants (particularly complete Freund's adjuvant or Bordetella pertussis) were donors capable of consistently transferring adoptive immunity. The total dose of inactivated VEE vaccine did not appear to influence the capacity to transfer adoptive immunity. On the other hand, weekly boosters of VEE vaccine and/or administration of vaccine with specific adjuvants did markedly influence donor immune responses.

Avian infectious bronchitis vaccine: primordial or derived virus?

Abstract: Vaccine formulations of virulent, modified/attenuated, or inactivated mono- or multivalent types of chicken embryo-propagated avian infectious bronchitis virus (IBV) at different passage levels and administered by non-parenteral routes have been used for immunization of chickens against the disease. Two doses of vaccines are generally used: 1) high level virus of lessened virulence, antigenicity and immunogenicity as "derived" from its parental virus via serial passage in and selective adaptation to the chicken embryo, and 2) low passage level virus with the above properties more closely related to the greater potency of the "primordial" parental virus in nature. The efficacy of vaccines with contemporary or candidate virus has been interpreted from a variety of criteria among which are: 1) clinical response, residence and dissemination of virus, 2) in vivo and in vitro local tissue response of tracheal epithelium, 3) protection against virulent homologous or heterologous types of IBV, and 4) induced secretory and humoral antibody. Vaccines have been economically useful and of epizootiological value but the greatest difficulty is the uncertainty of protection because of the changing antigenic, immunogenic and other properties of existing virus and of newly emerging types. With a complex virus such as IBV, the opportunities for natural selection and evolution of new or modified antigens via association with antibody of immune or of partially immune hosts are as enormous as antigenic lability resulting from fragmentation of the primordial genome under natural and/or artificial environmental stress. The present day IBV might be progeny from a unique pool of primordial genome via mutation and host-induced variation, or even persistence of primordial virus as an infinitesimal portion of the population.

An evalutation of some methods of assay of foot-and-mouth disease antigen for vaccines.

Abstract: The relative merits of various in vitro assay systems for the measurement of the quality and quantity of foot-and-mouth disease virus vaccine antigen will be discussed. The assay systems include : viral infectivity, complement fixing activity, particle counts, radial diffusion titre and single radial haemolysis titre. The predictive value of the tests for the immunogenicity of the final vaccine product will be evaluated against the results of 50% Protective Dose titres determined in guinea pigs and cattle by antibody assay and by challenge.

Improved method for production of attenuated Venezuelan equine encephalomyelitis (TC-83 strain) vaccine.

Abstract: Primary chicken embryo cell cultures were evaluated a s an alternate cell system for the production of attenuated Venezuelan equine encephalomyelitis (TC-83 strain) vaccine. The TC-83 strain virus was shown to remain stable during 10 serial passages in chicken embryo cell culture with regard to plaque size and morphology, virus yield, potency, and virulence for mice and hamsters.

Immunological control of virus-associated tumors in man: a perspective.

Abstract: The purpose of this Symposium has been to review the state of the art in 4 virus-associated tumor systems, i.e., lymphoma, leukemia, breast cancer, and cervical cancer, with the intent ion of identifying those aspects that are most applicable to current clinical problems. Fol lowing each session, the discussion leaders presented an overview of the problems pecul iar to their disease area, which was based on the material included in the Symposium papers (3, 11, 15, 16, 22). Since logistic considerat ions have prevented us from inc luding all of the papers presented at the meeting as well as many of the discussion points, this perspective will attempt to supplement the individual summaries by including addit ional pertinent material presented during the Symposium. As might have been expected, EBV\" required primary attention in th is meeting because it is the only virus that has been shown to be pathogenic for man, oncogenic for primates, and readily identif ied in human tumors. As noted by Epstein (6), it has taken a decade to bring us from detection of the virus to consideration of a vaccine, and the lessons learned from research involving EBV and related lymphotropic herpesvirus may be applicable to studies in other virus-tumor systems as well. While prevention continues to be a major goal of the field of viral oncology, a preventive vaccine for BL or any other human tumor does not appear to be on the immediate horizon for a number of reasons. As already stated (6), BL would be the most logical tumor to attack with a viral vaccine, but in this disease there is the problem of inoculating many normal individuals with potential ly hazardous material in order to prevent tumors in a few. As Holland (11) has observed in the case of acute leukemia, the decl in ing mortality due to improved conventional therapy diminishes the potential benefi t of even the most effective vaccine and BL, like acute leukemia, is exceedingly sensitive to chemotherapy. As discussed by Meyer and Ennis (17), the benefi t / r isk ratio is a cri t ical issue when inoculat ion of a normal individual is concerned. Our knowledge is growing rapidly, however, and these authors prudently observe that close interaction between basic scientists and regulatory agencies must be maintained as developments cont inue to arise in the laboratory and clinic. Such communicat ion may well avoid large efforts and expenditures in bui lding models that