Short Communications
Differential Viral Protein Expression in Kaposi's Sarcoma-Associated Herpesvirus-Infected Diseases: Kaposi's Sarcoma, Primary Effusion Lymphoma, and Multicentric Castleman's Disease

https://doi.org/10.1016/S0002-9440(10)64940-1Get rights and content
Under a Creative Commons license
open archive

Kaposi's sarcoma (KS)-associated herpesvirus (KSHV) is linked to KS, primary effusion lymphomas (PEL), and a subset of multicentric Castleman's disease (MCD). Transcript mapping studies using PEL cell lines have allowed preliminary classification of viral gene expression into constitutive (class I) and inducible (class II/III) categories. To determine whether viral gene expression differs in vivo, we examined tissue sections of KSHV-infected disorders, using specific antibodies against proteins that are representative of the different expression classes of KSHV genes. ORF73/LANA appears to be a surrogate marker for KSHV infection because it is constitutively expressed in vitro and in vivo in all KSHV-infected cells. Expression of vIRF1, vIL6, and PF-8 proteins in the infected B cells of MCD lymph nodes reproduces the expression pattern observed in TPA-stimulated KSHV-infected B-cell lines. In contrast, the protein expression of the inducible viral genes that we tested in KS and PEL biopsies is restricted to PF-8 and vIL6, respectively. The tightly restricted expression of KSHV proteins in vivo differs from the dysregulated expression of inducible KSHV genes in vitro and suggests that viral gene expression in KSHV-infected cell lines does not accurately reflect what occurs in diseased tissues. These differences may be related to either cell-specific or immune restriction of viral replication.

Cited by (0)

Supported by National Institutes of Health grants CA67391, CA75911, and CA82056; II Programma Nazionale di Ricerca sull'AIDS1998-ISS Project Number 30.A.0.50; and the Lucy Pang Yoa Chang Foundation.