5^5 
ON  THE  VARIATION  OF  THE 
HAEMOLYl'IC  COMPLEMENT  IN 
EXPERIMENTAL  TRYPANOSOMIASIS 
BY 
WARRINGTON  YORKE.  M.D. 
f  l^rorn  the  Runcorn  Research  Laboratories  of  the  Liver  fool  School  of 
Tropical  J / ed icine ) 
(Received  for  publication  5  February,  1910; 
Ilartoch  and  Yakimoff'’'  observed  a  diminution  in  the  amount  of 
haemolytic  complement  in  the  blood  of  guinea-pigs  and  rats  infected 
with  various  strains  of  trypanosomes  shortly  before  the  death  of  the 
animals. 
With  a  view  to  ascertaining  whether  this  diminution  of  the 
haemolytic  complement  bore  any  definite  relation  to  the  number  of 
trypanosomes  present  in  the  peripheral  blood  of  the  infected  animal, 
or  whether  it  was  simply  a  terminal  event  of  the  disease,  the  following 
series  of  experiments  was  undertaken,  t 
For  the  purpose  of. preparing  a  haemolytic  system  about  50  c.c.  of 
goat’s  red  corpuscles  were  injected  into  the  peritoneal  cavity  of  a 
rabbit,  all  traces  of  serum  having  been  previously  removed  from  the 
red  cells  by  washing  three  or  four  times  with  o'Q  per  cent.  NaCl 
solution.  These  injections  were  repeated  once  or  twice  at  intervals 
of  seven  days.  Usually  at  the  end  of  two  or  three  weeks  the  rabbit’s 
serum  was  .strongly  haemolytic  for  goat’s  red  cells.  The  immune 
rabbit-serum  was  then  inactivated  by  heating  to  56°-58°  C.  for  half 
an  hour. 
In  order  to  standardise  the  haemolytic  system,  amounts  varying 
*  Wien  klin.  Woch.,  No.  40,  1908. 
t  The  animal  experiments  recorded  in  this  paper  Avere  kindly  performed  for  me  bv 
Dr.  Anton  Breinl. 
