LACK OF CORRELATION BETWEEN EXPRESSION OF EPSTEIN-BARR-VIRUS (EBV) LATENT MEMBRANE-PROTEIN AND BCL-2 ONCOPROTEIN IN-VIVO

Aims-To evaluate whether there is any correlation between the expressi on of Epstein-Barr virus (EBV) latent membrane protein (LMP) and oncop rotein bcl-2 in the lymph node biopsy specimens of a Chinese patient w ith EBV-related reactive lymphoproliferation who later developed T cel l lymphoma after a short period of time. Methods-Immunohistochemistry, with a standard alkaline phosphatase antialkaline phosphatase (APAAP) method and New Fuchsin as a chromogen, was used for single staining o f bcl-2 or LIMP. Double immunostaining combining APAAP and indirect im munofluorescence was performed for dual labelling of LIMP and bcl-2. R esults-bcl-2 was expressed in 10-30% of cells in the first lymph node biopsy specimen (EBV-associated lymphoproliferative disorder) and 30-5 0% of cells in the second lymph node biopsy specimen (T cell lymphoma) . LIMP was expressed in the first biopsy specimen but not in the secon d. Double immunostaining results showed that around 78% of LMP positiv e cells were bcl-2 negative and 94% bcl-2 positive cells were LIMP neg ative. Among the very small fraction of LMP and bcl-2 double positive cells, the intensity of bcl-2 staining was heterogeneous and was not a lways stronger than that observed in LMP negative bcl-2 positive cells . Conclusions-The expression of bcl-2, protein is independent of LIMP protein status in vivo. Several mechanisms may be involved in EBV asso ciated lymphomagenesis, and bcl-2 induction may occur independently of LIMP expression.