Immune response in cattle induced by inactivated rabies vaccine adjuvanted with aluminium hydroxide either alone or in combination with avridine.

In a comparative study of two commercial baby hamster kidney rabies vaccines produced in Brazil, the authors were able to demonstrate the following: a) both vaccines provoked a high level of antibody response and protection against challenge in cattle b) in primary vaccination, at least, the addition of avridine (a synthetic lipoidal amine) enhances the immune response in terms of the level and persistence of antibody c) over 90% of cattle vaccinated with either vaccine were protected against experimental challenge one year after revaccination, and the antibody response profile indicated that these vaccines were capable of maintaining antibody titres above protective levels for more than two years after revaccination. On the basis of these results, the authors recommend optional revaccination of young animals (i.e. "primo-vaccinates") at six months of age. Thereafter, annual revaccination should be sufficient to ensure high levels of antibody between vaccination cycles.

Efficacy of avridine as an adjuvant for Newcastle disease virus antigen in chickens.

Avridine, a lipoidal amine with interferon-inducing and adjuvant properties, was an effective adjuvant for Newcastle disease antigen (NDA) in chickens. Eleven vaccine lots were evaluated: 2 commercial water-in-oil vaccines, 4 experimental oil emulsion vaccines, 4 avridine-containing vaccines, and a control lot of nonadjuvanted antigen. Avridine significantly enhanced the immunologic responses of chickens against NDA. Chickens vaccinated with the avridine-containing vaccines had significantly higher antibody titers (hemagglutination inhibition) than did chickens vaccinated with the commercial vaccines. Experimental oil emulsion vaccines prepared from the same antigens as avridine-adjuvanted vaccines induced higher hemagglutination inhibition antibody titers after primary but not after booster vaccination. Use of avridine as an adjuvant for NDA in vaccines for chickens induced immunologic protection rates similar to those induced by oil emulsion vaccines, without causing the reactogenic and tissue residue problems associated with the use of oil vaccines in chickens.

Producao da vacina anti-rabica veterinaria em suspensao de celulas BHK. / Veterinary antirabic vaccine production in BHK cells suspension

Em tanque de 150 litros de capacidade, contendo 100 litros de celulas BHK-21 cultivadas em suspensao, estas foram inoculadas com a amostra PV de virus fixo da raiva, para producao de vacina. Uma concentracao relativamente elevada de virus foi obtida apos 96 a 120 horas de cultivo, que permitiu a preparacao de vacina para imunizacao de caes e bovinos contra a raiva.Os testes laboratoriais de potencia pelos metodos do NIH, Habel e Koprowski foram plenamente satisfatorios. A vacina preparada para a imunizacao de bovinos, adicionada de hidroxido de aluminio, protegeu os 10 animais vacinados contra o desafio pela inoculacao de 4 x 10/8 DL50 (camundongo) e virus rabico isolado de morcego. Sao ainda apresentadas observacoes sobre a evolucao dos cultivos celulares e dinamica de replicacao viral nas suspensoes celulares usadas. Algumas das experiencias realizadas sugerem a possibilidade de preparacao de uma vacina nao inativada com a amostra PV