Evening star., 1938-12-09

and then to inoculate with the sus-
pension OF liver cells. The lukemia
fails to develop. This is believed
to be the first time in the history
of cancer research, he says, that
any type of induced resistance has
completely suppressed a-plastic
growth transferred before the pro-
tecting treatment was given
Superflcially, at least, it looks like
the work of a leukemia antibody.
Actual isolation of such a substance
in any form of cancerous growth
would constitute an enormous step
in advance. But there remains, DR..
MacDowell reports. one very puz-
cling hurdle, 1t has been completely
impossible thus far to separate the
substance from the living liver cells
of mice in whom active resistance
to leukemia previously has been
induced. Suspensions Of liver cells
of non-leukemic mice have no effect
whatsoever. " Is obvious that what.
ever the substance is 1t must be built
up by the cells themselves in their
own fight against the deadly in
vaders. 1t is completely destroyed
when the cells are killed.
Another puzzling feature of the
experiments Is that the protective
substance in the liver cells is built
up only in response to the attack
Of leukemia cells themselves. 1t
cannot be built up In a mouse by
trcati it with liver cells of ac-
lively immunized mice. They them
selves become immune but their
Hvers do not produce the protective
substance. The amount, or strength,
of the material increases propor-
tionate to the degree of active re-
SlStance developed by successive sub.
lethal doses Of leukemic cells.
May Open New Field.
The reports suggest the pOSSi-
bility that the Carnegie research
workers may have hit upon some
thing belonging to class of sub
stances hitherto unknown in medi-
cine and biology, and thus may have
opened up a field far wider than
that Of possible prevention Of malig-
nant neoplasms. Such substances.
not themselves living entities, would
work only when forming part OF the
complex of living entities. They
might be compared to biological po-
licemen who can act with authority
only as members of a legally con-
stituted force. Acting as an in
dividual the policeman has no more
power to suppress disorders than
any other citizen.
Says the Carnegie report Of the
work: "A possible lead for a
chemical analysis and clue to
tho difficulty Of obtaining non-
cellular substances that resist
neoplastic growth have been found
in the amazing ease with which
the effectiveness Of this supposed
substance can be destroyed me-
chanically. The method is simply
to force the saline suspension OF
minced tissue out Of a syringe held
firmly against the bottom Of the
vessel. In a very few minutes all
cells are torn to pieces. Is the
protecting substance denatured by
the same pressure that destroys the
cells, or is 1t so closely associated
with cell structure, possibly as q
modification of some normal cell
constituent, that cell destruction is
responsible for the inactivation?
when injected into a mouse the
cells OF minced tissue are destroyed
but the effectiveness Of the pro-
lection that accompanies them may
persist for at least two weeks.
"The recent advances in organic
chemistry have disclosed such elabo-
rate organizations of protein mole
cules as to approach the assumed
complex organization of living mat
ter. The chemist can no longer