Rapid loss of both CD4+ and CD8+ T lymphocyte subsets during the acute phase of severe acute respiratory syndrome

Abstract

Objective: To study the alteration of peripheral lymphocyte subsets in severe acute respiratory syndrome (SARS) patients and to help improve the early diagnosis of the disease.

Methods: Anti-coagulating blood samples from 98 SARS patients in the acute phase, 56 normal healthy blood donors, and from patients infected by HIV, CMV and EBV were collected. The T lymphocyte subsets were counted by flow cytometry using fluorescence-labeled specific monoclonal antibodies.

Results: A significant decrease was observed in all SARS patients in their peripheral CD4(+) and CD8(+) T lymphocyte absolute counts [256 (104) x 10(6)/L and 256 (117) x 10(6)/L, respectively], which were also lower than those of the patients infected with HIV, CMV and EBV. All patients infected with HIV, CMV and EBV had significantly higher CD8(+) T lymphocyte counts in comparison with normal controls.

Conclusions: Decrease of both CD4(+) and CD8(+) T lymphocytes of patients is related to onset of SARS. T lymphocyte subset analysis would help improve the early diagnosis of the disease.