1076 
ANIMAL RESOURCES 
days of age where it stabilizes for the rest of 
the dog's life. The shift in P50 as the dog 
grows is accomplished without the production 
of new hemoglobins but is correlated with the 
levels of diphosphoglycerate.^ 
The use of red cell blood groups in defining 
dogs in this colony has been developed with the 
aid of Dr. Scott N. Swisher.^ Members of the 
colony are typed for the Swisher canine blood 
groups A (Ai and A2 alleles), B, C and D and 
the antiserums needed to detect these antigens 
are all produced in this colony. Current research 
efforts in the blood group system include efforts 
to better define the A blood group by absorption 
and a search for new dog blood groups. 
The genetics studies in this colony have been 
concerned with coat color inheritance, and 
genetic mechanisms of deleterious traits includ- 
ing hip dysplasia, entropion, and glaucoma. 
The main emphasis has been on preliminary 
studies of the theoretical possibilities of breed- 
ing a histocompatible dog. It was considered 
that the conventional method of full sib matings 
used to produce histocompatible lines of rodents 
would be a difficult way to produce histocompat- 
ible dogs because of the longer generation time 
of dogs, the greater chromosome number (Dog 
2N = 78), and the amount of space needed to 
hold enough dogs to buffer the deleterious ef- 
fects of inbreeding. These reasons also make the 
full sib inbreeding economically unfeasible for 
dogs. The breeding plan chosen was to develop 
in-vitro methods for direct selection on histo- 
compatible antigens and to test progeny histo- 
genically by skin allografts. 
The method of one-way stimulation by mixed 
leukocyte culture (MLC) was developed initially 
for use in the histocompatibility studies because 
of the contributions MLC has made to the un- 
derstanding of human transplantation genetics.'^ 
After the MLC test was established the lympho- 
cyte toxicity test was adapted using four an- 
tisera designated A, B, C and D provided by Dr. 
E. D. Thomas, Seattle, Washington and four 
antisera designated d, e, F and G provided by 
Dr. J. W. Ferrebee, Cooperstown, New York. 
These eight canine anti-lymphocyte isoantisera 
had proved useful in matching dogs for pro- 
longed allograft survival.^-^ 
The preliminary studies of breeding a histo- 
compatible dog were to determine the genetics of 
the dog transplantation antigens, to test the 
efficiency of selecting breeders hy in-vitro meth- 
ods that recognize histocompatibility antigens, 
and to assemble lines of dogs that have the same 
transplantation antigen phenotype for inbreed- 
ing. 
The transplantation genetics studies were 
initially attempted by doing family studies with 
the eight cytotoxic antisera and by MLC stud- 
ies that Bach and Amos used to study HL-A 
genetics in humans.'^ The family studies with 
the cytotoxic antisera were not very rewarding. 
The specificities of the antisera used are too 
broad to collect segregation and linkage data. 
There will need to be more antisera with nar- 
rower specificities produced before the tech- 
nique of cytotoxicity can be utilized to study 
the genetics of transplantation antigens. In this 
regard, two new antisera have been produced in 
this colony. Littermate dogs which were 
matched with the eight cytotoxic antisera but 
were mismatched in MLC were cross-immunized 
with lymphocytes. Both dogs developed anti- 
bodies to each other's lymphocyte antigens (see 
Table III). 
The transplantation genetic studies using 
MLC were more productive. The results were 
MLC reactivity between all 296 pairs of unre- 
lated dogs tested and no MLC reactivity be- 
Table III. — The lymphocyte antigen phenotype and 
MLC results of littermate dogs, no. 9222 and no. 
9223 
Dog no. 
Swisher 
Blood 
Group 
A B 
C D 
d 
E 
F 
G 
9222 
C 
+ + 
- + 
+ 
+ 
+ 
+ 
9223 
+ + 
- + 
+ 
+ 
+ 
+ 
MLC Results 
Responding Cells 
u 
_c 
'■♦3 
a 
9222r 
9223r 
X ? 
9222, 
571 ^ 
2373 
4938 
imul 
9223s 
1805 
447 
2262 
CO 
X, 
4230 
2805 
221 
" Unrelated control dog. 
•> Average of two cultures each 
Dogs 9222 and 9223 were cross immunized with 10^ lymphocytes 
intravenously three times. 
9222 developed 1:40 titered antiserum against 9223's lymphocytes. 
9223 developed 1:20 titered antiserum against 9222's lymphocytes. 
