CHARACTERIZATION OF EPSTEIN-BARR VIRAL STRAINS IN PAROTID-GLAND SALIVA AND PERIPHERAL-BLOOD OF PATIENTS WITH PRIMARY SJOGRENS-SYNDROME AND HEALTHY EBV CARRIERS

Increased Epstein-Barr virus (EBV) replication has been reported in th e salivary and lacrimal glands in Sjogren's syndrome (SS). We studied whether or not certain EBV strains would occur preferentially in the p eripheral blood and parotid gland saliva of 18 EBV-seropositive patien ts with primary Sjogren's syndrome (pSS) and 12 EBV-seropositive contr ol persons. Transforming EBV was detected in the blood of 11 of 18 (61 %) pSS patients and 9 of 12 controls (75%). Unexpectedly, neither tran sforming nor Raji-superinfecting EBV strains were detected in SS parot id saliva, whereas these EBV types were detected in control saliva in 7 and 8 cases, respectively (P < 0.001). Transforming EBV strains were further characterized by 'Ebnotyping', i.e., analysis of the size spe ctrum of the viral antigens EBNA 1, 2, 3, and 6 in immunoblots of lymp hoblastoid cell lines (LCL). Previous work has shown that a single EBV strain (Ebnotype) dominates the blood and oropharynx of healthy carri ers and that unrelated individuals carry different EBV strains, reflec ting the vast polymorphism of Ebnotypes in the general population. Two unexpected observations were made. First, an identical Ebnotype was d etected in 4 unrelated individuals, i.e., in the blood of 1 pSS patien t and in the saliva of 3 control persons. Second, carriage of 2 to 4 d ifferent Ebnotypes by a single individual was observed in 4 cases, i.e ., in the blood of 1 pSS patient, and in the blood and saliva of 3 con trol persons. As only 1 control person had received a blood transfusio n, it is suggested that (super)infection with exogenous EBV strains vi a salivary transmission and/or recombination of endogenous virions may have contributed to this situation. (C) 1993 Wiley-Liss, Inc.