Summary
Tissue factor (TF), the principal procoagulant of human brain, resides in specific
regions of the non-human primate central nervous system. Immunohistochemical studies
employing murine anti-human TF monoclonal antibodies (MoAbs) detected TF antigen in
the cortex, basal ganglia, cerebellum, and cervical spinal cord in three normal baboon
subjects. Although significantly less prominent than human cortical gray matter, a
distinct partition of TF in gray matter >white matter was noted. The gray matter predilection
of TF was confirmed in primate temporal and parietal lobe cortex by both sandwich
ELISA and one-stage coagulation assay. Variation in the relative quantity of TF antigen
was observed by ELISA among the three subjects studied. Procoagulant activity followed
the pattern of TF antigen (cortical gray matter >basal ganglia ≥cerebellum >cortical
white matter), and was 96.5–98.5% inhibitable by a function inhibiting anti-human
TF MoAb combination. TF antigen was associated with the microvasculature of all cerebral
tissues studied, and spared capillaries most selectively in the cerebral cortex, basal
ganglia, and cerebellum. These findings suggest a highly specific ordering of TF antigen
and related procoagulant activity in the central nervous system of the baboon, confined
primarily to gray matter parenchyma, and to the non-capillary microvasculature.
