Ultrastructural, cytochemical, and membrane surface marker characteristics
of the atypical lymphocytes in infectious mononucleosis
RW McKenna, J Parkin, KJ Gajl-Peczalska, JH Kersey and RD Brunning
Atypical lymphocytes from nine young adults with acute infectious
mononucleosis (IM) were studied for morphologic, ultrastructural,
cytochemical, and membrane surface marker characteristics. There was an
absolute increase in T lymphocytes in the patients. Atypical lymphocytes
accounted for 83%-96% of the lymphocyte population. These lymphocytes
contained cytoplasmic inclusions which ranged in size from 1000 to 6000 A,
were usually membrane bound, and consisted of parallel arrays of
microtubulelike structures. The inclusions, which have been referred to as
parallel tubular arrays (PTA), were found in 15%-75% of the lymphocytes
from the IM patients. Ultrastructural cytochemical methods demonstrated
acid phosphatase activity within many of the membrane-bound PTA. The
function of the PTA is unknown. Since they were observed only in the
lymphocytes which appeared to correspond to the atypical lymphocytes on
light microscopy, the majority of which typed as T cells, there appears to
be an association between PTA and T lymphocytes. It is possible that PTA
identify a specific subset of T lymphocytes which is expanded in IM.
Alternatively, PTA may be a transient finding in lymphocytes appearing only
in certain biologic states of the cell such as during T-lymphocyte
activation.
Volume 50,
Issue 3,
pp. 505-515,
09/01/1977
Copyright © 1977 by The American Society of Hematology
