The stability of the intratypic antigenic character of sabin's type 1 attenuated virus (LSc-2ab)

Abstract

The recognition of antigenic differences among the polio viruses belonging to the same type (1, 2, 3, 4, 5, 6) provides an important means for their differentiation, especially useful in studies for the control of oral polio vaccination.

Identificação sorológica intratípica de poliovírus pelo "método da comparação dos índices de neutralização"

“…Na primeira semana após a vacinação, a proporção de estirpes homó-logas era elevada (95,6%) ; na segunda semana, a proporção baixou para 71,8%; na terceira semana, a proporção era apenas de 25,5%; e, a partir da quarta semana, havia somente 11,1% de estirpes homólogas à estirpe atenuada de Sabin. Diversos outros autores também encontraram uma reversão antigênica (antigenic drift), se bem que em menor grau (VoNKA, JANDA & TUCKOVA, 1962 84a ; VONKA et al 84 1967). Demonstrada a labilidade do caráter antigênico da estirpe atenuada de Sabin, do tipo I, após a sua multiplicação nos intestinos humanos, torna-se mais difícil a determinação da proveniência de uma estirpe desconhecida, isolada de um caso clínico.…”

The Stabilizing Effect of L-Cystine on the Thermal Inactivation of Poliovirus

“…Genetic markers such as d, rct/40 and monkey neurovirulence have been found rather unstable, when the vaccine virus undergoes multicycle proliferation and passages through the human intestine, while the serological properties have been considered more stable and strain-specific under such circumstances. The inf ormations useful for the intratypic serological differentiation of the strains of poliovirus have been reported by several workers (Wenner et al, 1959;McBride, 1959; Gard et at., 1960;Wecker, 1960; Plotkin et at., 1961; Gelf and, 1962, 1963;Wasserman and Fox, 1962;Vonka et at., 1962;Woods et at., 1962;Ozaki et at., 1963;Kitahara et at., 1963 a).During the study on the stabilizing effect of L-cystine on various strains of poliovirus against thermal inactivation, it was found that there were considerable differences in the rate of the thermal stabilization by cystine between the strains derived from the attenuated poliovaccine strain (Sabin) and other wild or virulent strains, which belonged to the same immunogenic type. This communication deals with the kinetics of the thermal inactivation of various strains of poliovirus in the presence of different concentrations of L-cystine, and the results obtained by a simplified method for intratypic differentiation of poliovirus by the use of cystine.…”

“…Genetic markers such as d, rct/40 and monkey neurovirulence have been found rather unstable, when the vaccine virus undergoes multicycle proliferation and passages through the human intestine, while the serological properties have been considered more stable and strain-specific under such circumstances. The inf ormations useful for the intratypic serological differentiation of the strains of poliovirus have been reported by several workers (Wenner et al, 1959;McBride, 1959; Gard et at., 1960;Wecker, 1960; Plotkin et at., 1961; Gelf and, 1962, 1963;Wasserman and Fox, 1962;Vonka et at., 1962;Woods et at., 1962;Ozaki et at., 1963;Kitahara et at., 1963 a).…”