40
H. P. R. SEELIGER AND K. HOHNE
L. monocytogenes is still valid although it had to be extended after the demonstration of further antigenic factors.
Paterson’s antigenic scheme was confirmed repeatedly, i.e. by Robbins
and Griffin (1944, 1945a, 1945b), who studied the effect of disinfectants
on the flagellar antigens with particular reference to the production
of antibodies against the various components of the antigenic mosaic.
The results are summarised in the following: among the 0 antigens the
factors 1, 2, 4 and 5 are thermostable. Their antigenic power is not influenced by high concentrations of alcohol. After treatment with heat or
alcohol many, but not all, strains lose the ability to stimulate production of
agglutinin against 0-factor 3. The agglutinability, however, is not influenced. Robbins and Griffin ascribe the variability of factor 3 to its particular chemical structure as well as to the arrangement and distribution of
factor 3 molecules within the bacterial cell. Possibly factor 3 represents a
surface antigen analogous to L antigens of Enterobacteria. It may be
recalled that serotypes 1/2a, 4a and 4b are usually found in pathological
material from diseased animals and man, while the other serotypes were
rarely recognised and mostly originated from faecal specimens of Listeriu
carriers. In consequence, the serological identification of serotypes other
than 1/2a (or b) and 4b is not necessary for routine purposes. The same
may hold true for serotypes based on the presence or absence of H-factor
C which is difficult to demonstrate. So far, serotypes of L. monocytogenes
have never been found to be correlated to any particular clinical syndrome
nor to any particular host, although their distributions, particularly of
serotypes 1 /2a and 4b show remarkable geographical differences (vide
infru). .
B. Methods for preparation of Listeria antigens 0-antigens
0-antigens are prepared from smooth cultures incubated on 1 % glucose
tryptose agar for 24 h at 37°C. The harvested growth is suspended in
physiological phosphate-buffered saline (pH 7.2) and boiled in the
steamer in order to destroy the H-antigens. Then phenol is added to a
final concentration of 0.5%. I n order to eliminate the tendency to spontaneous agglutination, all 0 suspensions are treated by ultrasonic oscillation
for 5-10 min. Frequency and duration of ultrasonic treatment depend on the
density of suspension and the degree of spontaneous clumping. At lmHz
and 32-38 W 5-10 min treatmtnt yields the desired results.
H-Antigen
H-antigens are prepared by adding equal amounts of 0.6% formolised
saline to highly motile cultures in phosphate-buffered 1% glucose tryptose
broth after 24-48 hr incubation at 22-24°C. The presence of very active
H. P. R. SEELIGER AND K. HOHNE
L. monocytogenes is still valid although it had to be extended after the demonstration of further antigenic factors.
Paterson’s antigenic scheme was confirmed repeatedly, i.e. by Robbins
and Griffin (1944, 1945a, 1945b), who studied the effect of disinfectants
on the flagellar antigens with particular reference to the production
of antibodies against the various components of the antigenic mosaic.
The results are summarised in the following: among the 0 antigens the
factors 1, 2, 4 and 5 are thermostable. Their antigenic power is not influenced by high concentrations of alcohol. After treatment with heat or
alcohol many, but not all, strains lose the ability to stimulate production of
agglutinin against 0-factor 3. The agglutinability, however, is not influenced. Robbins and Griffin ascribe the variability of factor 3 to its particular chemical structure as well as to the arrangement and distribution of
factor 3 molecules within the bacterial cell. Possibly factor 3 represents a
surface antigen analogous to L antigens of Enterobacteria. It may be
recalled that serotypes 1/2a, 4a and 4b are usually found in pathological
material from diseased animals and man, while the other serotypes were
rarely recognised and mostly originated from faecal specimens of Listeriu
carriers. In consequence, the serological identification of serotypes other
than 1/2a (or b) and 4b is not necessary for routine purposes. The same
may hold true for serotypes based on the presence or absence of H-factor
C which is difficult to demonstrate. So far, serotypes of L. monocytogenes
have never been found to be correlated to any particular clinical syndrome
nor to any particular host, although their distributions, particularly of
serotypes 1 /2a and 4b show remarkable geographical differences (vide
infru). .
B. Methods for preparation of Listeria antigens 0-antigens
0-antigens are prepared from smooth cultures incubated on 1 % glucose
tryptose agar for 24 h at 37°C. The harvested growth is suspended in
physiological phosphate-buffered saline (pH 7.2) and boiled in the
steamer in order to destroy the H-antigens. Then phenol is added to a
final concentration of 0.5%. I n order to eliminate the tendency to spontaneous agglutination, all 0 suspensions are treated by ultrasonic oscillation
for 5-10 min. Frequency and duration of ultrasonic treatment depend on the
density of suspension and the degree of spontaneous clumping. At lmHz
and 32-38 W 5-10 min treatmtnt yields the desired results.
H-Antigen
H-antigens are prepared by adding equal amounts of 0.6% formolised
saline to highly motile cultures in phosphate-buffered 1% glucose tryptose
broth after 24-48 hr incubation at 22-24°C. The presence of very active