Significant elevation of B cells at the acute stage in enterovirus 71-infected children with central nervous system involvement

Abstract

A feature of the large outbreak of human enterovirus 71 (EV71)-associated hand-foot-and-mouth (HFMD) disease in China in 2008 was that severe cases presented with encephalitis. This study was performed to evaluate the immunophenotypic characteristics of patients with neurological involvement. Twenty-one patients with encephalitis and 14 with uncomplicated HFMD were recruited. Age-matched healthy volunteers were enrolled as controls. Peripheral lymphocyte subsets were analyzed by use of 3-colour flow cytometry, and the quantitative determination of plasma immunoglobulin (Ig) levels was also monitored. Comparisons between severe and mild cases demonstrated significant elevations of B cells and IgG levels and corresponding general decreases in natural killer (NK) cells and T lymphocytes in severe cases at the acute stage of infection (p < 0.01 for all). During the convalescent phase, rapid recoveries of B cells and IgG to the normal levels were observed, which appeared to be accompanied by an increase in EV71-specific neutralizing antibody titres. In summary, our data demonstrate that elevated B cells and IgG might be associated with neurological manifestations in EV71 infection.

Acknowledgements

This study was funded by the National Key Technologies R&D Program for the 11^th Five-year Plan (2008ZX10001-006), Clinical Disciplines Key Project of the Ministry of Health, the Specialized New Teacher Research Fund for the Doctoral Program of Higher Education of the Ministry of Education of China (No. 20070023057), Peking Union Medical College Hospital Research Fund for Young Investigators (No. 2006108) and Beijing Nova Program (No. 2008B49).

Declaration of interest: The authors declare that they have no competing financial interest.