Culture Vaccine Research Articles

Schémas réduits de traitement antirabiqueavec les nouveaux vaccins de cultures cellulaires

Summary The original ≪Pasteur treatment≫ required long series of daily injections of rabbit medulla suspension of increasing virulence. Even with the Fermi and Semple types of inactivated sheep brain vaccines, these long series remained necessary, with a high risk of neuroparalytic accidents. The first possibility of using redu ced schedules of post-exposure vaccination appeared after 1955 with the sucklingmouse-brain vaccine. But it was only after 1965, with the newly developed cell culture vaccines, (mainly the human diploid cell vaccine), that a reduced schedule of rabies treatment of only 6 injections could be recommended by the WHO. This WHO scheme is now widely used with other cell culture vaccines in several countries. New reduced schedules of rabies post-exposure vaccination are presently under study with the aim of inducing an immune response as early as possible and, at the same time, reducing the amount of vaccine used (and thus the cost of vaccination) and the number of injections: the multi-site method and the intradermal route of injection have proven to be very efficient in this respect.

Cross protection of mice against different rabies virus isolates

In an attempt to identify “atypical” strains which could account for vaccination failures, 10 street, one intermediate (DR19) and 4 fixed rabies virus isolates from men, cattle, dogs, cats, mongoose and vampire bats in five countries (Argentina, Brazil, Chile, Cuba, and France) were studied by cross-protection tests in mice. For the purpose of this study, any virus that killed more than 20 % of the vaccinated mice challenged with that virus was considered “atypical”. When the suckling mouse brain rabies vaccine was used, two “atypical” isolates were found: one, from a human case in Chile (91, 125 mouse passages) and the other, from a vampire bat in Brazil (DR19, 22 mouse passages). However, when mice immunized with a cell culture vaccine (PV-BHK) of a higher antigenic value than the brain vaccine, were challenged with those same isolates, mortality was below 20%. The fact that these two isolates killed enough vaccinated mice to be considered “atypical” could be related to antigenic differences between these viruses and those included in the vaccine. However, since this mortality was observed only in the mice immunized with the vaccine with a lower antigenic value, reasons are given why it could be attributed to other biological characteristics of those strains than antigenic differences. Causes for vaccines failures other than immunological differences of rabies virus strains are also analyzed and discussed.

Simple techniques for increasing the batch size of rinderpest cell culture vaccine.

Simple techniques for increasing the batch size of rinderpest cell culture vaccine.

The duration of immunity in cattle following inoculation of rinderpest cell culture vaccine.

The duration of immunity following a single administration of rinderpest cell culture vaccine, of 90 or more monolayer passages, was studied in E. African zebu (Boran) and grade (cross-bred European) cattle. All animals were kept for periods of 6-11 years in rinderpest-free environments; groups of them (in all 23 Borans and 10 grades) were then challenged by parenteral or intranasal inoculation of virulent virus or by contact exposure to reacting cattle. Nasal excretion of virus was studied daily over the 10-to 14-day period following challenge, and simultaneous attempts were made to detect viraemia. The neutralizing antibody response was followed at 6-month intervals over the whole post-vaccination period and then daily for 10 days and at longer intervals to 3 weeks after challenge. All 33 animals which were exposed by various routes failed to react clinically and a rinderpest viraemia was never detected. No transmission of virus from the vaccinates to susceptible in-contact controls occurred within 14 or more days, from the 20 animals which could be so tested. Clearcut serological responses to challenge were seen in six cattle (four Borans and two grades) which were challenged after 7 years or more; these reactions were all delayed to the 9th or 10th days, i.e. they were not typically 'anamnestic'. These results are discussed in relation to mass vaccination campaigns for the control of rinderpest and from the comparative viewpoint of measles vaccination in man.

Effect of some cultural factors on T1 broth vaccine for contagious bovine pleuropneumonia.

The effect of some aspects of buffering capacity, glucose concentration, length of incubation and extent of exposure to air during the preparation of live Mycoplasma mycoides var. mycoides strain T1 broth culture vaccine was investigated. A consistently good vaccine was obtained using 0.07 M phosphate buffered medium containing 0.1% glucose and incubating in stoppered bottles. The shelf-life of this vaccine stored at 4 degrees C was up to 12 weeks. The effect of other storage temperatures on the viability of the vaccine is given.

‘Red Book’ Update

UPDATE The Red Book Committee met on May 10, 1982 and considered a number of issues, including: 1. The 1982 edition (19th) of the Red Book has been distributed beginning on June 4, 1982. We welcome comments and suggestions for the 20th edition. 2. IMPORTANT REVISION IN RED BOOK RECOMMENDATIONS: After the Committee meeting it came to our attention that three children who had anaphylactoid reactions to egg ingestion experienced immediate allergic reactions to chick-embryo-grown live measles virus vaccine; two had difficulty breathing and one had hypotension. Persons who are egg-allergic but do not have a history of anaphylactoid reactions appear to be at little or no risk from live measles virus (LMV) vaccine (See Morbidity Mortality Weekly Rep 31:217-231, May 7, 1982). Because previous experience indicated no adverse reactions in egg-allergic children given vaccine prepared in chick embryo tissue culture, the 1982 Red Book contains the following statement: The vaccine currently used in the United States is prepared in chick embryo tissue culture by inoculation with a further attenuated passage of the Edmonston B strain of measles virus. This preparation is virtually devoid of allergenic substances derived from the chick embryo cell cultures used for growth of the live vaccine viruses. However, there is a remote potential risk of hypersensitivity reactions in patients allergic to eggs, chicken, or chicken feathers; large scale use of the vaccine for more than a decade has resulted in only rare, isolated reports of minor allergic reactions. In a study in which children known to be allergic to eggs, chicken, or chicken feathers were vaccinated with a chick embryo cell culture-derived vaccine, no allergic reactions were observed.

Booster Effect of Human Diploid Cell Antirabies Vaccine in Previously Treated Persons

Contact was maintained with 27 of 45 persons for four years after their severe exposure to rabies virus and successful protection. During that time, these persons showed no adverse effects of treatment and maintained rabies-neutralizing antibody at the level of 2 to 91 IU/mL of serum. After a single booster inoculation of human diploid cell culture vaccine four years after the initial treatment, levels of neutralizing antibodies rose to 36 to 650 IU/mL of serum ten days after the booster inoculation. These observations confirm the persistence of rabies-specific serum antibodies for an extended (four years) period after vaccination. Furthermore, a single booster inoculation with human diploid cell culture vaccine resulted in a sharp increase in the level of antibodies, indicating that a person would probably be protected against a second exposure.

Exposure of guinea pigs to Rickettsia rickettsii by aerosol, nasal, conjunctival, gastric, and subcutaneous routes and protection afforded by an experimental vaccine.

Guinea pigs were inoculated with Rocky Mountain spotted fever by the aerosol, conjunctival, subcutaneous, intragastric, and intranasal routes. Rickettsial infection was produced by all routes except intragastric. All animals with clinical signs of disease developed agglutinating antibody, and most developed a cell-mediated immune response. Disease produced by all experimental routes (except intragastric) was indistinguishable. The tissue culture-derived inactivated vaccine produced in this laboratory protected guinea pigs against an aerosol challenge.

Vaccination of Children With Human Cell Culture Rabies Vaccine

Three children exposed to the bites of proved or probably rabid animals were immunized with human rabies immune globulin and human diploid cell culture vaccine. There were no significant clinical reactions, and all three developed high levels of rabies antibody. The patients have remained well from four to 18 months.

The development and evaluation of a cell culture vaccine against infectious laryngotracheitis virus

The development and evaluation of a vaccine against infectious laryngotracheitis virus (ILTV) using an avirulent Australian strain propagated in chicken embryo kidney cell culture is described. Yields of cell culture-grown vaccine virus per embryo were at least as high as yields obtained by the Chorio-allantoic Membrane (CAM) method. Freeze-dried preparations of stabilized cell culture vaccine showed no loss in infectivity after storage at 4°C for 12 months. In a dose-response trial using 9-day-old ILTV-susceptible chickens vaccinated by the ocular route, the 50% protective dose against challenge with virulent ILTV was shown to be approximately 100 plaque-forming units per bird.

Immunoglobulin (IgG) and (IgM) antibody responses to rabies vaccine.

IgM and IgG neutralizing antibody responses were estimated in the sera of rabbits and mice immunized with different doses of Semple, duck embryo and cell culture rabies vaccines. IgM synthesis was prolonged in animals immunized with multiple doses of either Semple or duck embryo vaccines but not those immunized with cell culture vaccine. Mice were passively protected by IgG antibody against subsequent challenge but not by IgM of equivalent neutralizing titre. Mice challenged when the antibody response was solely IgM were not protected if the transition to IgG synthesis was prevented by cyclophosphamide treatment.

A cell culture vaccine against bovine ephemeral fever.

A vaccine was prepared from cell culture fluids harvested from the twelfth passage of the 919 strain of bovine ephemeral fever (BEF) virus in Vero cell cultures. Cattle were vaccinated subcutaneously with various combinations of strain 919 virus and adjuvants. Neutralising antibodies were assayed at various times after vaccination and some cattle were challenged by intravenous inoculation with the virulent 417WBC strain of BEF virus. Strain 919 virus of the third and twelfth passage levels in Vero cells produced neither fever, clinical illness nor detectable viraemia in 5 calves inoculated intravenously. Nor could viraemia be detected in 5 heifers receiving vaccine subcutaneously. When the vaccine was administered mixed with aluminium hydroxide adjuvant, the production of neutralising antibodies increased with an increase in the volume of vaccine from 2.5 ml to 10 ml and the response to 2 injections was significantly better than the response to a single injection. The neutralising antibody response was decreased when vaccine was diluted in phosphate buffered saline. The neutralising antibody response following 2 subcutaneous vaccinations with strain 919 virus mixed with aluminium hydroxide adjuvant was higher than that following intravenous inoculation with virulent virus. The vaccine-induced antibodies persisted for at least 12 months, and revaccination at this time led to an increase in the titre of neutralising antibody. Antibodies induced by a single subcutaneous administration of strain 919 virus mixed with Freund's complete adjuvant persisted for at least 40 weeks; those induced by vaccine containing Freund's incomplete adjuvant had virtually disappeared within 16 weeks. All these calves responded to vaccination with aluminium hydroxide-containing vaccine with increases in levels of neutralising antibodies. Of 26 vaccinated calves challenged with virulent BEF virus, 24 remained clinically normal. Two developed brief periods of pyrexia on the seventh day after challenge, but no other clinical signs. One of these calves had a viraemia that was demonstrated only by intravenous inoculation of a susceptible calf. The remaining calf had no detectable viraemia. All of 7 unvaccinated calves developed severe clinical BEF within 5 days of challenge. No disease attributable to the 919 virus occurred in 24 vaccinated pregnant heifers or their newborn calves.

A comparison of the Pasteur and Pitman-Moore strains of rabies virus for the production of rabies vaccine in human diploid cells

Paris Pasteur strain of rabies virus was adapted to multiplication in human diploid cell strains. Four lots of purified tissue culture vaccine prepared with this virus were compared with two similar vaccine lots prepared with the Pitman-Moore strain of rabies virus. According to the NIH test for potency, the vaccine prepared with the Pitman-Moore virus was about eight times more potent than the vaccine prepared with the Paris Pasteur strain of rabies virus. Both vaccines, however, elicited similar antibody responses in volunteers after four vaccine doses. Although the NIH test for potency may not represent a good parallel for immunogenicity of tissue culture rabies vaccine in man, the use of Pitman-Moore strain of virus seems preferable for the preparation of rabies vaccine in cultures of human diploid cells.

Observations on the use of live-modified tissue culture vaccine against Sheep Pox

Observations on the use of live-modified tissue culture vaccine against Sheep Pox

Prophylactic immunization of humans against rabies by intradermal inoculation of human diploid cell culture vaccine.

The antirabies human diploid cell vaccine produced by 1'Institute Merieux, Lyon, France, was administered intradermally to 35 high-risk volunteers using 0.2-ml amounts and various immunization schedules. Three groups never before vaccinated against rabies developed virus-neutralizing antibodies, the titer of which was dose dependent. A single injection stimulated the formation of antibodies. Four inoculations induced the highest antibody levels and the longest persistence of antibody. The administration of a single intradermal booster inoculation was sufficient, even in the case of low-persisting antibody, to elicit a rapid increase of antibodies to high levels. A primary inoculation course of two injections induced a sufficient antibody level which, in case of exposure, could apparently be rapidly elevated by a 0.2-ml intradermal booster inoculation. Adverse side reactions were observed in 7 of 14 individuals after a 1- or 1.5-year intradermal booster inoculation. We therefore suggest that the intramuscular and subcutaneous routes continue to be used for primary vaccinations and that the highly effective intradermal route be restricted to booster inoculations. This is the first long term study of this vaccine and should be a guideline for the pre-exposure treatment of high-risk personnel.

VIROLOGIC CONSIDERATIONS ON ANTI-DENGUE VACCINE

Possibilities of developing an anti-dengue vaccine are discussed based on our experimental findings with a dengue virus type 1 (DEN-1) Mochizuki strain. The Mochizuki strain virus was attenuated for human beings in the course of several passages through mouse brains since its isolation from the blood of a dengue patient in the 1943 epidemic in Nagasaki, Japan. This attenuated virus in the living state induced no abnormal symptoms after injection into human volunteers or monkeys, yet it stimulated production of specific anti-DEN-1 NT and HI antibodies and induced a prophylactic effect on the human beings against virulent dengue viruses (in the form of patient's serum) given experimentally. The immunogenic effects of the virus was maintained after passages in primary monkey kidney tissue cultures. Using the tissue culture virus, together with the 17D yellow fever (YF) vaccine, a combined immunization of human beings against DEN and YF was possible; production of the antibodies of significant titers against both viruses was unequivocally demonstrated. The partially purified virus was similarly effective in stimulating production of the anti-DEN antibodies, and the same statements could be made as to the viral components obtained by sucrose density gradient centrifugation. The virus was shown to multiply in the WI-38 cell line cultures, and this suggests application of this cell line to produce a live tissue culture vaccine.Conclusions of this review are : (1) the Mochizuki virus is completely attenuated; (2) yet it stimulates production of specific anti-DEN antibodies and induces protection against DEN-1 infection by virulent human virus; and (3) that possibility of developing a live tissue culture vaccine is suggested; this also makes possible a combined DEN-YF vaccination on the experimental basis. It is stated in the connection that the purified virus or its components can be used for the above purposes.Problems regarding the implication of “hypersensitivity hypothesis” of dengue and dengue hemorrhagic fever-shock syndrome in anti-DEN vaccination are in addition discussed.

Immunisation of cattle against the herpesvirus of malignant catarrhal fever: failure of inactivated culture vaccines with adjuvant

Attempts were made to immunise cattle against the herpesvirus of malignant catarrhal fever by inoculating living or formalinised preparations of the agent, propagated in cell cultures and combined with Freund's incomplete adjuvant. High and persistent levels of virus-neutralising antibody were regularly demonstrable, especially following two intramuscular inoculations at an interval of six to eight weeks. In spite of this no protection was demonstrable against parenteral challenge with virulent virus, whether in cell-free or cell-associated form. In a controlled field trial vaccinated cattle showed no evidence of protection against natural challenge by exposure to wildebeest herds. It was concluded that humoral mechanisms are probably not important in determining resistance to infection with virulent MCFV.

Cell-mediated immune response in cattle to Mycoplasma mycoides var. mycoides.

The cell-mediated immune response of cattle to Mycoplasma mycoides var. mycoides was studied. Sensitized lymphocytes in blood leukocyte preparations showed a significant degree of antigen-induced transformation, judged by the uptake of tritiated thymidine. The increase in tritiated thymidine uptake in sensitized lymphocytes in the presence of M. mycoides membrane antigen varied from 2- to 13-fold compared with the controls, and this increase in activity was observed from 3 days after artificial infection. Inhibition of leukocyte migration by M. mycoides membrane antigen commenced between 17 and 30 days after infection, and preliminary observations indicate that this test correlated with the intradermal allergic test. M. mycoides-induced unresponsiveness was demonstrated 23 and 30 days after infection. Unresponsiveness, in that the lymphocytes did not respond to phytohemagglutinin, was very marked in two of three animals and partial in the third animal, whereas the humoral antibody response did not appear to be affected. Antigen-induced transformation was demonstrated in only two out of six cattle vaccinated two months previously with M. mycoides T(1) broth culture vaccine, and óne animal only gave a doubtful intradermal allergic reaction. A further six cattle vaccinated 15 months previously were negative to both the leukocyte migration inhibition test and the intradermal allergic test.

Immune response in primates vaccinated with duck embryo cell culture rabies vaccine.

Adult rhesus monkeys (Macaca mulata) were vaccinated with four inactivated rabies vaccines, including two cell culture vaccines, one zonal purified cell culture vaccine, and a 10% extracted duck embryo vaccine. The vaccines were potency tested by both National Institutes of Health (NIH) and Habel methods and passed one or both tests. However, a vaccine having acceptable potency by one method frequently failed or was marginal by the other procedure. Groups of three monkeys were inoculated with each vaccine by one of two schedules. The first consisted of four weekly 1-ml doses followed by a 1-ml booster dose at 6 months, and the second consisted of seven daily 1-ml doses of vaccine with no booster. Both zonal purified and extracted duck embryo vaccines induced detectable neutralizing antibody by day 7 with either schedule, and antibody titers elicited by the cell culture vaccine remained high through 210 days. However, antibody titers produced by the 10% duck embryo vaccine dropped sharply after their 28-day peak. Duck embryo cell culture vaccines with low or marginal potency as measured by Habel or NIH tests still produced rapid, high levels of serum-neutralizing antibody in primates. LD(50) or NIH and Habel tests as measured in mice were not necessarily good indices of antibody response in the primate host. The need for a cell culture potency test that will yield a more predictable correlation with the definitive host's antibody response is discussed.

Immune Response in Primates Vaccinated with Duck Embryo Cell Culture Rabies Vaccine

Adult rhesus monkeys (Macaca mulata) were vaccinated with four inactivated rabies vaccines, including two cell culture vaccines, one zonal purified cell culture vaccine, and a 10% extracted duck embryo vaccine. The vaccines were potency tested by both National Institutes of Health (NIH) and Habel methods and passed one or both tests. However, a vaccine having acceptable potency by one method frequently failed or was marginal by the other procedure. Groups of three monkeys were inoculated with each vaccine by one of two schedules. The first consisted of four weekly 1-ml doses followed by a 1-ml booster dose at 6 months, and the second consisted of seven daily 1-ml doses of vaccine with no booster. Both zonal purified and extracted duck embryo vaccines induced detectable neutralizing antibody by day 7 with either schedule, and antibody titers elicited by the cell culture vaccine remained high through 210 days. However, antibody titers produced by the 10% duck embryo vaccine dropped sharply after their 28-day peak. Duck embryo cell culture vaccines with low or marginal potency as measured by Habel or NIH tests still produced rapid, high levels of serum-neutralizing antibody in primates. LD(50) or NIH and Habel tests as measured in mice were not necessarily good indices of antibody response in the primate host. The need for a cell culture potency test that will yield a more predictable correlation with the definitive host's antibody response is discussed.