Unusual expression of CD94 on CD8+ TCR-αβ T cells in infectious mononucleosis

Ren, Yongsheng; Medeiros, L. Jeffrey; Amin, Hesham M.; Rytting, Michael E.; Jorgensen, Jeffrey L.; Chen, Weina

doi:10.1016/j.anndiagpath.2006.06.005

« Previous Next »Annals of Diagnostic Pathology
Volume 11, Issue 1 , Pages 55-60, February 2007

Unusual expression of CD94 on CD8⁺ TCR-αβ T cells in infectious mononucleosis

Yongsheng Ren, MD, PhD
- Department of Hematopathology, Box 72, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA
L. Jeffrey Medeiros, MD
- Department of Hematopathology, Box 72, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA
Hesham M. Amin, MD
- Department of Hematopathology, Box 72, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA
Michael E. Rytting, MD
- Department of Pediatrics, Box 72, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA
Jeffrey L. Jorgensen, MD, PhD
- Department of Hematopathology, Box 72, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA
Weina Chen, MD, PhD
- Department of Hematopathology, Box 72, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA
- Corresponding author. Tel.: +1 314 648 5196; fax: +1 214 645 6315.

Abstract

Infectious mononucleosis, caused by primary Epstein-Barr virus (EBV) infection, is usually a benign, self-limited lymphoproliferative disorder. We report a case of a 21-year-old woman who presented with fever, sore throat, severe neutropenia, and absolute lymphocytosis with atypical lymphocytes. In situ hybridization for EBV-encoded small RNA performed on the marrow aspirate clot specimen demonstrated scattered positive cells. EBV serology was compatible with primary infection. Flow cytometry immunophenotypic studies performed on aspirate material revealed a profoundly expanded population of CD8⁺ T-cell receptor (TCR)-αβ T cells with uniform expression of CD94. No evidence of a monoclonal T-cell population was found as assessed by V_β use with flow cytometry and by TCR γ-chain gene rearrangement using a polymerase chain reaction method. Uniform expression of CD94 in an exuberant reactive proliferation of CD8⁺ TCR-αβ T cells in infectious mononucleosis has not been reported previously, and combined with atypical morphology might be misinterpreted as a malignant neoplasm.

Keywords: CD94, NK cell receptors, Immunophenotype, Infectious mononucleosis