LIVE POLIO IRUS VACCINES

DR. ÉOBBINS: In the course of our studies of
newborn infants, we thought that perhaps the
high acidity of their stomachs might have something
to do with the lower rate of intestinal infection
in these children. Therefore, in conversation
with Dr. Sabin, it occurred to us that perhaps
we could adsorb the virus to aluminum
hydroxide, a technique he described many years
ago, along with other people.
Discussion 45
Discussion
45
stead of variable bicarbonate concentration, variations
You will recall that the virus adsorbs at an
in the concentration of sodium chloride in acid pH and elutes at an alkaline pH. This
the medium are substituted. Agol and Chumakova
seemed made to order for our purpose, since
concluded that the active factor was not
the bicarbonate (Na 2 HCO 3 ), but merely the
the virus presumably would remain adsorbed
in the stomach and elute in the intestine.
Na+ cation. An appropriate communication However, in testing this in vitro, we found
giving the experimental evidence will appear in
a forthcoming issue of the Russian journal Problems
that the Type 1, LSc 1 ab vaccine strain behaved
quite differently from the Mahoney strain. The
of Virology. Of course, one cannot com-
pattern of behavior is quite similar to that
pletely rule out the possibility of a coincidence
of the d marker and the bicarbonate marker, but
such a coincidence would be so remarkable that
one has to consider first a modification of our
described by Dr. Hodes in that the more attenuated
virus fails to elute, whereas the Mahoney
virus elutes very readily, as expected.
In Table 1, data from a series of experiments
views regarding the mechanism of the d marker,
used so widely in the studies on poliovirus
genetics.
with Mahoney virus are presented. These experiments
were done very simply by suspending
virus with the aluminum gel at pH 5.5 to 6.
The suspension is centrifuged and the adsorption
determined by titration of the supernate.
The gel is then washed with the acid buffer and
resuspended in a buffer of pH 7.5. The suspension
is centrifuged again and the eluate
tested for viral content. The recovery of the
Mahoney virus is almost quantitative, whereas
with the Sabin LSc strain a very small proportion
of the virus was eluted.
We have tested one Type 1 virus isolated from
ADSORPTION AND ELUTION OF TYPE 1 POLIOVIRUSES
TO AL (OH) 3 GEL SUSPENSIONS
TITER (LOG TCID 5 0 /0. 1 ML.)
VIRUS ORIGINAL T. C.F. AFTER ADSORPTION ELUATE
7.5 3.8 7.4
MAHONEY 7. 6 3. 8 7. 6
4.5 0.5 4. 0
7.7 4.0 2.0
SABIN (LSC) 7.0 4.5 4.0
4.5 0 < 2.0
TYPE 1 (FROM
PARALYTIC CASE) 4.0 0 3.0
SABIN (LSC)
2 DAYS POST-
FEEDING 7.0 5.0 < 1. 0
32 DAYS POST-
FEEDING 7.0 4.2 2.5
TABLE 1