title: Tubuloreticular inclusions and paired cisternae induced in human lymphocytes cultured with Staphylococcus aureus Cowan 1.
abstract: Tubuloreticular inclusions (TRI) and paired cisternae (PC) were induced in lymphocytes of normal individuals after incubation with Staphylococcus aureus Cowan 1. TRI were initially detected in lymphoid cells on day 2 (48-h culture). The frequency of TRI-positive cell sections on day 5 increased about twofold over those on days 2-4. On day 7, TRI were predominantly seen in lymphoplasmacytoid cells or plasmacytoid cells, with an incidence of up to 18% of sections. The regions in these cells were most extensive and anastomosed with the cisternae of adjacent well-developed rough endoplasmic reticulum (RER). TRI formation appears not to be essential for mitogen-induced B-cell differentiation to plasmacytoid cells, because pokeweed mitogen (PWM) failed to induce TRI. The diverse expressions of TRI induction between these two mitogens may be due to a difference in B-cell activation mechanisms. Paired cisternae were observed in a great majority of mitotic cells at various stages. These were encountered most frequently on day 4. PC were also seen in the PWM-stimulated culture. Our observations suggest that PC formation may be related to new formation of RER as well as to reconstruction of the nuclear envelope.
mesh_terms: D002478:Cells, Cultured; D006801:Humans; D008214:Lymphocytes / Q000166:cytology / Q000382:microbiology / Q000648:ultrastructure*; D008854:Microscopy, Electron; D009940:Organoids / Q000648:ultrastructure*; D013211:Staphylococcus aureus