Blood, 1970, Vol. 35, No. 3, pp. 386-393.
© 1970 American Society of Hematology, Inc.
Ultrastructural Aspects of Antibody Plaque-Forming
Cells from Clinically Normal and Overtly
Autoimmune NZB Mice
B. V. SIEGEL 1,
R. E. BROOKS 1, and
JANE I. MORTON 1
1 Department of Pathology and Division of Immunology, Allergy and Infectious
Diseases, University of Oregon Medical School, Portland, Oregon.
Quantitative differences, in terms of antibody plaque-forming cells per mg.
spleen, were observed in young and old animals of the BALB/c and NZB
mouse strains. Ultrastructurally, antibody-producing cells from spleens of immunologically hyperactive young NZB mice appeared relatively similar to those
from overtly autoimmune old NZB mice showing depressed immune responsiveness. There was more extensive dilatation of endoplasmic reticulum in cells of
older mice, with some of these cells manifesting increased fragility. Viruslike
particles, observed to be located intracisternally, lacked an electron dense
nucleoid and were not seen budding from plasma membranes; they were thus
unlike the murine leukemia type-C particles reported to be found in organs of
NZB mice. Additionally, since these viruslike particles were observed in antibody-producing cells of young and old nonautoimmune BALB/c mice as well
as in those of the NZB strain, it is probable that they do not represent the agent
responsible for development of autoimmune disease or malignancy.
Submitted on June 16, 1969
Accepted on October 15, 1969
