Viral induction, transmission and apoptosis among cells infected by a Human Intracisternal A-type retrovirus

Sjogren's Syndrome, a systemic autoimmune disease, is characterized by lymp hocytic infiltration of the salivary or lacrimal glands, producing xerostom ia or xerophthalmia. Although definitive proof of viral etiology has not be en established, a cell line containing viral particles termed Human Intraci sternal A-type Particles (HIAP) resulted from co-culture with patient lip b iopsies. We stimulated these chronically infected cells with phorbol myrist ate acetate (PMA) in an effort to enhance production of viral particles for further characterization. We report that the virus present in the HIAP cel l line can be induced to become lytic when subjected to PMA and that there is a difference in the effects of PMA on H9 and HIAP cell groups, with appa rent protection from apoptosis due to PMA being exerted by viral presence. Delayed apoptosis may prolong exposure of the foreign/self complex, thus en hancing an autoimmune response. Polyacrylamide gel electrophoresis (PAGE) r evealed the presence of new peptides in pellets of supernatants of PMA-stim ulated HIAP cells, with prominent bands at 55 and 43 kDa, and several faint er ones. HIAP infection was transferred by cell-free filtered supernatants from stimulated cells to H9 cells, which became identical to parent HIAP ce lls by PAGE and fluorescence activated cell sorter. (C) 1999 Elsevier Scien ce B.V. All rights reserved.