Co-infection of herpes simplex virus type 1 (HSV-1) and human cytomegalovirus (HCMV) is not uncommon in immunocompromised hosts. Importantly, organ transplant recipients concurrently infected with HSV-1 and HCMV have a worse clinical outcome than recipients infected with a single virus. However, factors regulating the pathologic response in HSV-1, HCMV co-infected tissues are unclear. We investigated the potential biologic role of HCMV gene product immediate early 1 (IE1) protein in HSV-1-induced syncytial formation in U373MG cells. We utilized a co-infection model by infecting HSV-1 to U373MG cells constitutively expressing HCMV IE1 protein, UMG1-2. Syncytial formation was assessed by enumerating nuclei number per syncytium and number of syncytia. HSV-1-induced syncytial formation was enhanced after 24 hr in UMG1-2 cells compared with U373MG controls. The amplified phenotype in UMG1-2 cells was effectively suppressed by roscovitine in addition to inhibitors of viral replication. This is the first study to provide histological evidence of the contribution of HCMV IE1 protein to enhanced cytopathogenic responses in active HSV-1 infection.
Cell Line, Tumor ; Giant Cells/*virology ; Herpesvirus 1, Human/*growth & development ; Humans ; Immediate-Early Proteins/biosynthesis/*metabolism ; Protein Kinase Inhibitors/pharmacology ; Purines/pharmacology ; Transfection ; Virus Replication/drug effects

Castleman's disease represents an atypical lymphoproliferative disorder, infrequently associated with various immunologic abnormalities or subsequent development of malignancy such as Kaposi sarcoma, malignant lymphoma and plasmacytoma. Its clinicopathologic features depend on various etiologic factors such as Kaposi sarcoma herpesvirus (KSHV), oversecretion of IL-6, adhesion molecule and follicular dendritic cell dysplasia, etc. To investigate the relationship of Castleman's disease (CD) and the above factors, we reviewed 22 cases of CD. Four cases of KSHV positive CD were detected, all multicentric, plasma cell type, and these cases displayed prominent vascular proliferation, characteristic 'Kaposi-like lesion'. IL-6 and CD54 positive mononuclear cells were scattered in interfollicular areas of KSHV positive cases. Follicular dendritic cell hyperplasia, vascular proliferation, expression of IL-6 and CD54 did not show any significant difference between solitary vs multicentric type, and plasma cell type vs hyaline vascular type. Our study suggests that KSHV positive CD reveals unique pathologic features, and the probable relationship of KSHV and IL-6 and CD54 is discussed.
Adolescence ; Adult ; Biological Markers ; Dendritic Cells, Follicular/pathology ; Epstein-Barr Virus Infections/virology ; Epstein-Barr Virus Infections/epidemiology ; Female ; Germinal Center/pathology ; Giant Lymph Node Hyperplasia/virology ; Giant Lymph Node Hyperplasia/pathology+ACo- ; Giant Lymph Node Hyperplasia/epidemiology ; Giant Lymph Node Hyperplasia/classification ; Herpesviridae Infections/virology ; Herpesviridae Infections/epidemiology ; Herpesvirus 4, Human/isolation +ACY- purification ; Herpesvirus, Kaposi Sarcoma-Associated/isolation +ACY- purification ; Human ; Hyperplasia ; Intercellular Adhesion Molecule-1/analysis ; Interleukin-6/analysis ; Korea/epidemiology ; Lymph Nodes/virology ; Lymph Nodes/pathology ; Lymph Nodes/chemistry ; Male ; Middle Age ; Neovascularization, Pathologic ; Receptors, Complement 3d/analysis ; Retrospective Studies ; Tumor Virus Infections/virology ; Tumor Virus Infections/epidemiology

OBJECTIVEAlthough HIV-1 infection is prevalent in many regions in China, it remains largely unknown on the biological characteristics of dominant circulating isolates. This study was designed to isolate the circulating viral strains from different prevalent regions and to characterize their biological properties and neutralization sensitivity.

METHODSPrimary viruses were isolated from fresh PBMCs using the traditional co-culture method and their capacity of inducing syncytium was tested in MT-2 cells. Meanwhile, their coreceptor usage was determined with two cell lines: Magi and GHOST (3) stably expressing CD4 and the chemokine receptor CCR5 or CXCR4. Furthermore, the sensitivity of these viruses to neutralization by HIV-1-infected patients' plasma which were highly active to neutralize SF33 strain, was quantified in GHOST cell-based neutralization assay.

RESULTSSix primary viral strains were isolated from 4 separated regions. Isolates LTG0213, LTG0214 and XVS032691 induced syncytia in MT-2 cells, and used CXCR4 as coreceptor. Isolates XJN0021, XJN0091, or SHXDC0041 did not induce syncytia, and used CCR5 as coreceptor. Overall neutralization sensitivity differed among four representative strains: HIV-1 XVS032691 > LTG0214 >XJN0091 approximately SHXDC0041.

CONCLUSIONThe neutralization sensitivity of HIV isolates is linked with the phenotype of isolates, in which syncytium-inducing (SI) or CXCR4-tropic (X4) viruses are more easily neutralized than non-syncytium-inducing (NSI) or CCR5-tropic (R5) viruses. The genetic subtypes based on the phylogeny of env sequences are not classical neutralization serotypes.

CD4-Positive T-Lymphocytes ; metabolism ; Cell Line ; Cells, Cultured ; Chemokines ; genetics ; immunology ; China ; Coculture Techniques ; methods ; Giant Cells ; ultrastructure ; virology ; HIV Infections ; virology ; HIV Seropositivity ; genetics ; immunology ; HIV-1 ; immunology ; isolation & purification ; physiology ; Humans ; Neutralization Tests ; Receptors, CCR5 ; metabolism ; Receptors, CXCR4 ; metabolism ; Virus Replication