RESUMO
Kaposi's sarcoma-associated herpesvirus (KSHV) was found in the bone marrow dendritic cells of multiple myeloma patients but not in malignant plasma cells or bone marrow dendritic cells from normal individuals or patients with other malignancies. In addition the virus was detected in the bone marrow dendritic cells from two out of eight patients with monoclonal gammopathy of undetermined significance (MGUS), a precursor to myeloma. Viral interleukin-6, the human homolog of which is a growth factor for myeloma, was found to be transcribed in the myeloma bone marrow dendritic cells. KSHV may be required for transformation from MGUS to myeloma and perpetuate the growth of malignant plasma cells.
Assuntos
Medula Óssea/virologia , Células Dendríticas/virologia , Herpesvirus Humano 8/patogenicidade , Interleucina-6/análise , Mieloma Múltiplo/virologia , Southern Blotting , Medula Óssea/patologia , Transformação Celular Neoplásica , DNA Viral/análise , Células HL-60 , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/isolamento & purificação , Herpesvirus Humano 8/fisiologia , Humanos , Hibridização In Situ , Interleucina-6/genética , Interleucina-6/fisiologia , Mieloma Múltiplo/patologia , Paraproteinemias/patologia , Paraproteinemias/virologia , Reação em Cadeia da Polimerase , Células Estromais/patologia , Células Estromais/virologiaRESUMO
Human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus, has been implicated in the pathogenesis of Kaposi's sarcoma (KS), primary effusion lymphoma (PEL), multicentric Castleman's disease, and recently multiple myeloma (MM). DNA sequence analyses of HHV-8 suggest that multiple HHV-8 strains exist. We extracted DNA from 24 patients with MM and 3 patients with monoclonal gammopathy of undetermined significance and compared HHV-8 open reading frames (ORFs) 26 and 65 sequences with those derived from patients with KS, PEL, and two HHV-8-positive PEL cell lines KS-1 and BC-1. ORF26 sequence data suggest that MM patients are consistently carriers of HHV-8 strain subtype C3. All MM patients also consistently revealed either a single bp deletion or substitution at position 112197 in ORF65. This unique alteration is not present in patients with KS or PEL or in PEL cell lines. It occurs in the portion of ORF65 that is known to be responsible for a serological response to HHV-8.
Assuntos
Herpesvirus Humano 8/genética , Linfoma/virologia , Mieloma Múltiplo/virologia , Fases de Leitura Aberta , Sarcoma de Kaposi/virologia , Sequência de Aminoácidos , Sequência de Bases , Humanos , Dados de Sequência MolecularRESUMO
We have recently demonstrated the presence of Kaposi's sarcoma-associated herpesvirus (KSHV) in cultured bone marrow (BM) stromal dendritic cells from all patients with myeloma studied. To show that these findings were not an artifact of tissue culture, we performed in situ hybridization (ISH) and polymerase chain reaction (PCR) to detect KSHV in BM core biopsies. Using ISH to open reading frame-72 (ORF 72), we localized KSHV to BM dendritic cells in 17 of 20 patients with myeloma, 2 patients with plasmacytosis associated with the acquired immunodeficiency syndrome, and 1 case of aplastic anemia. In contrast, BM from normal subjects (n = 4) and patients with lymphoma and leukemia (n = 21) did not contain KSHV. PCR amplification with KSHV primers demonstrated product in fresh BM biopsy samples from 6 of 7 myeloma patients, whereas three normal marrows contained no amplified product. These findings suggest that KSHV, possibly through alterations in the BM microenvironment and production of viral interleukin-6 (vIL-6), may stimulate and maintain abnormal plasma cell proliferation in myeloma and related disorders.