Page 98 - JSOM Summer 2019

lacking in highly tactical and far-forward environments. Ca- Crossmatching procedures were conducted in accordance
nine transfusion products can be prepositioned at designated with previously described procedures. 19,20 First, all human and
locations, but the high rate of prehospital death for MWDs canine RBCs were washed, except those that were obtained
wounded in action highlights the urgent need for transfusion from the commercial kit. Briefly, all citrated blood tubes were
12
products at the point of injury. Research and development of centrifuged (Thermo Scientific, Legend XTR, Waltham, MA)
field-ready canine transfusion products should continue, but at 1000g for 2 minutes. Then 100μL packed RBCs was pipet-
human blood is a potential resource for lifesaving hemostatic ted into a 12×75mm test tube. Next, 3mL of normal saline
resuscitation in the most dire of trauma scenarios. was added to each tube, mixed thoroughly, and centrifuged at
1000g for 60 seconds. The supernatant saline was aspirated
Although rare, xenotransfusions with canine blood to felines from the RBCs and discarded. The RBCs were washed two ad-
is occasionally used clinically when feline blood is desperately ditional times for a total of three washes. After the last wash,
needed and none is available. Results of xenotransfusions the supernatant saline was aspirated, and the RBCs were cen-
with canine blood to felines have mixed results, but overall trifuged at 1000g for 15 seconds to prepare a packed cell but-
successful outcomes have been reported, lending credence ton. The tube was filled with 4mL of normal saline, mixed
18
to the notion that successful xenotransfusions are possible. thoroughly, and labeled as RBC suspension. The serum sep-
The safety and practicality of whole blood xenotransfusion arator tubes were centrifuged at 2000g for 15 minutes, and the
from humans to canines have not been explored in the modern serum was removed and placed into individual labeled tubes.
era. Because canine blood products are commercially readily
available, there is virtually no application for the practice of Major Crossmatch
human-to-canine xenotransfusion in the civilian veterinary
sector, accounting for the lack of prior research efforts. In the major crossmatch, serum from 10 different GOCs (rep-
resenting the recipient) was mixed with human RBCs (repre-
This project is the first step toward determining if human senting the donor). For human blood, two samples of A+, one
blood administration is a safe and effective treatment option sample of A–, one sample of B+, one sample of O–, and two
for far-forward military human healthcare providers who samples of O+ plus washed RBCs from the commercial test kit
need to care for severely wounded MWDs. We hypothesized containing A–, B–, and O+ RBCs were crossmatched against
that transfusing human blood into a canine would result serum from 10 different GOCs. The test tubes were labeled
in significant cross-reactivity in both the major and minor with human donor ID and the word Major. Then, 100μL of
crossmatches. “patient” (GOC) serum and 50μL of “donor” (human) RBC
suspension were added to the tube, shaken gently, covered,
and incubated at 37°C for 15 minutes. Additionally, eight
Materials and Methods
control samples were used. For each control, the canine RBC
This experiment was approved by the Department of De- suspension was mixed with the canine’s own serum. Each tube
fense (DoD) Military Working Dog Veterinary Services’ was removed from the incubator and centrifuged at 1000g for
( DODMWDVS) Institutional Animal Care and Use Commit- 15 seconds. The tube was then removed from the centrifuge,
tee. Whole blood was collected from 20 GOCs stationed at taking care not to dislodge the red cell button, and evaluated
Joint Base San Antonio-Lackland into two blood collection (both macroscopically and, if necessary, microscopically) on a
tubes: one containing citrate anticoagulant and one serum sep- white background by a board-certified veterinary pathologist.
arator tube. Simultaneously, a second serum separator tube
and a tube containing EDTA were also collected for routine Minor Crossmatch
procurement bloodwork. Each GOC was deemed healthy
based on history, physical examination, and results of a com- In the minor crossmatch, plasma from seven different people
plete blood count (CBC) and biochemical analysis as per- (of the blood groups listed earlier) and one sample of pooled
formed at the DODMWDVS. human plasma were mixed with five samples of canine DEA
1–positive and five samples of DEA 1–negative RBC suspen-
Blood tubes from these GOCs were refrigerated and trans- sion. A test tube was labeled with human donor ID and the
ported from the DoD Military Working Dog Center on Lack- word Minor. Then, 100μL of human plasma and 50μL of
land AFB to the US Army Institute of Surgical Research for GOC RBC suspension were added to the tube, shaken gen-
analysis. Canine blood was then typed for dog erythrocyte tly, covered with the tube stopper, and incubated at 37°C for
antigen (DEA) 1 by using a commercially available, Rapid- 15 minutes. In addition, seven control samples were used. For
Vet -H testing kit (DMSlaboratories, Flemington, NJ) per the each control, the human RBC suspension was mixed with the
®
manufacturer’s instructions. Blood was then refrigerated in a human’s own plasma. Each tube was removed from the incu-
medical-grade refrigerator until the next day. bator and centrifuged at 1000g for 15 seconds. The tube was
then removed from the centrifuge, with care taken to not dis-
Human blood was obtained from two sources. Washed human lodge the red cell button, and evaluated (both macroscopically
RBCs were procured from Kemtec Science (ABO Blood Typing and, if necessary, microscopically) on a white background by a
Kit: Real Human Blood Cells, Hanover, PA) containing 5mL board-certified veterinary pathologist.

aliquots of A–, B–, and O+ washed RBCs. Additionally, one
blood tube with citrate anticoagulant was obtained from seven Grading
human donors at the US Army Institute of Surgical Research’s
Blood Research Laboratory following established procedures. Each tube was shaken gently to dislodge the red cell button,
These blood samples contained the following blood types: two and the manner in which RBCs left the button was observed.
A+, one A–, one B+, two O+. and one O–. Red-tinged (free hemoglobin) color of the supernatant lighter

96 | JSOM Volume 19, Edition 2 / Summer 2019