Reverse transcriptase in leukocytes of leukemic patients in remission

Area of Science:

• Molecular Biology
• Hematology
• Oncology

Background:

• Cytoplasmic particulate fractions from human leukemic cells contain reverse transcriptase and an associated RNA template.
• The presence of this reverse-transcriptase-template complex in leukemic cells suggests a potential role in disease pathogenesis.

Purpose of the Study:

• To investigate the presence of the reverse-transcriptase-template complex in peripheral blood leukocytes of patients with acute leukemia in complete remission.
• To determine if morphologically normal leukocytes from remitted leukemia patients exhibit biochemical characteristics associated with leukemic cells.

Main Methods:

• Analysis of endogenous reverse transcriptase activity using velocity glycerol gradient and cesium sulfate equilibrium gradient centrifugation.
• Detection of the reverse-transcriptase-template complex in leukocytes from patients in remission and healthy controls.

Main Results:

• The reverse-transcriptase-template complex was detected in a significant proportion of leukocytes from leukemia patients in remission (3/9 by glycerol gradient, 8/10 by cesium sulfate gradient).
• The complex was not detected in leukocytes from normal individuals.
• Positive reactions indicate that some biochemical characteristics, possibly viral-related, persist in apparently normal leukocytes of remitted leukemia patients.

Conclusions:

• Morphologically normal peripheral blood leukocytes from some acute leukemia patients in remission retain biochemical markers associated with leukemic cells.
• These findings suggest that viral-related components may persist in the peripheral blood of leukemia patients even during remission.