Human herpesvirus type 8 in HIV-infected patients with interstitial pneumonitis

Association of polymorphisms in NFκB1 promoter and NFκBIA gene with the development of antibodies against HHV-8 in HIV-infected individuals

Human gammaherpesvirus 8 (HHV-8) is the etiologic agent of Kaposi's sarcoma, multicentric Castleman's disease and primary effusion lymphoma. Like other herpesviruses, the HHV-8 may exhibit latent or lytic cycle, both regulated by viral and host factors. Regarding host factors, we analysed the association of polymorphisms in NFkB1 promoter (NFkB1-94 ins/del ATTG) and NFκBIA gene (NFκBIA 3'UTR A→G) with the development of antibodies against latent or lytic antigens from HHV-8. The ins/del [OR 7.9 (95% CI 3.3-19.1), p < 0.001], AG [OR 12.3 (95% CI 4.3-34.9) p < 0.001], GG [OR 9.4 (95% CI 3.2-27.9), p < 0.001], ins/del + AG [OR 94.5 (95% CI 9.6-924.4), <0.0001], ins/del + GG [OR 50.4 (95% CI 5.2-482.2, p < 0.0001] and G allele [OR 3.3 (95% CI 2.0-5.6), p < 0.001] were strongly related with the presence of antibodies to lytic antigens. This is the first association of polymorphisms in NFκB1 promoter and NFκBIA gene with the development of antibodies against HHV-8.

Proteomics of Bronchoalveolar Lavage Fluid Reveals a Lung Oxidative Stress Response in Murine Herpesvirus-68 Infection

Murine herpesvirus-68 (MHV-68) productively infects mouse lungs, exhibiting a complex pathology characteristic of both acute viral infections and chronic respiratory diseases. We sought to discover proteins differentially expressed in bronchoalveolar lavage (BAL) from mice infected with MHV-68. Mice were infected intranasally with MHV-68. After nine days, as the lytic phase of infection resolved, differential BAL proteins were identified by two-dimensional (2D) electrophoresis and mass spectrometry. Of 23 unique proteins, acute phase proteins, vitamin A transport, and oxidative stress response factors Pdx6 and EC-SOD (Sod3) were enriched. Correspondingly, iNOS2 was induced in lung tissue by seven days post-infection. Oxidative stress was partly a direct result of MHV-68 infection, as reactive oxygen species (ROS) were induced in cultured murine NIH3T3 fibroblasts and human lung A549 cells infected with MHV-68. Finally, mice infected with a recombinant MHV-68 co-expressing inflammatory cytokine murine interleukin 6 (IL6) showed exacerbated oxidative stress and soluble type I collagen characteristic of tissue recovery. Thus, oxidative stress appears to be a salient feature of MHV-68 pathogenesis, in part caused by lytic replication of the virus and IL6. Proteins and small molecules in lung oxidative stress networks therefore may provide new therapeutic targets to ameliorate respiratory virus infections.

Human Herpesvirus 8 in Perinatally HIV-infected Children with Interstitial Lung Disease

INTRODUCTION

Human herpesvirus 8 (HHV-8) is associated with the pathogenesis of Kaposi Sarcoma and interstitial pneumonitis in adults. This study aims to evaluate association between HHV-8 and interstitial lung disease in HIV-infected children.

METHODS

HIV-infected children with interstitial pneumonitis underwent lung biopsies in a tertiary hospital and were investigated for HHV-8, Epstein-Barr virus (EBV) and cytomegalovirus (CMV) using polymerase chain reaction (PCR) and immunohistochemistry in lung tissue. Peripheral blood PCR was also performed for HHV-8.

RESULTS

From six patients included, PCR for HHV-8 was positive in lung samples in four children and in peripheral blood in one. PCR for EBV and CMV and immunohistochemical study for HHV-8, EBV and CMV in lung were negative in all patients.

CONCLUSION

No previous cases of HHV-8-associated interstitial pneumonitis was described in HIV-infected children. An immunological disorder and an infectious agent might influence development of the lymphoid interstitial pneumonitis. HHV-8 may be this infectious trigger.

High seroprevalence of human herpesvirus type 8 infection in males with advanced lung carcinoma

Human herpesvirus type 8 (HHV-8) DNA is consistently found in all types of Kaposi's sarcoma, which is prevalent in immunocompromised patients. Patients with advanced lung carcinoma often showed immunologic abnormalities, and prevalence of HHV-8 infection is unclear. In this study, blood samples from 109 lung carcinoma patients and 109 age- and sex-matched healthy controls were analyzed for lymphocyte and monocyte counts, and for antibody, DNA, and genotype of HHV-8. Lung carcinoma patients had significantly lower lymphocyte and higher monocyte counts than healthy controls (p < 0.0001, both). HHV-8 seropositivity was more prevalent in lung carcinoma patients (41.3%), particularly in male patients (50.8%), than in controls (24.8%) (p = 0.01 and 0.002, respectively). The seropositivity was also significantly higher in male (50.8%) than female patients (27.3%, p = 0.01). Titers of HHV-8 antibody in patients also significantly exceeded those in controls (p = 0.004). Under a higher threshold (antibody titer ≥1:160) which is equivalent to that of enzyme-linked immunosorbent assay, lung carcinoma patients still had higher HHV-8 seropositivity than controls (p = 0.006). Three patients with stage IV lung carcinoma were positive for HHV-8 DNA with K1 gene subtype C3, D1, and E, respectively; they had much lower lymphocyte counts (658 ± 132 µL) than patients positive for HHV-8 antibodies only (1,449 ± 873 µL). The study indicates that lung carcinoma patients, particularly males, have a high seroprevalence of HHV-8. HHV-8 DNA detected in the patients with advanced lung carcinoma may be a result of virus reactivation in the immunocompromised status.

β-HHVs and HHV-8 in Lymphoproliferative Disorders

Similarly to Epstein-Barr virus (EBV), the human herpesvirus-8 (HHV-8) is a γ-herpesvirus, recently recognized to be associated with the occurrence of rare B cell lymphomas and atypical lymphoproliferations, especially in the human immunodeficiency virus (HIV) infected subjects. Moreover, the human herpesvirus-6 (HHV-6), a β-herpesvirus, has been shown to be implicated in some non-malignant lymph node proliferations, such as the Rosai Dorfman disease, and in a proportion of Hodgkin’s lymphoma cases. HHV-6 has a wide cellular tropism and it might play a role in the pathogenesis of a wide variety of human diseases, but given its ubiquity, disease associations are difficult to prove and its role in hematological malignancies is still controversial. The involvement of another β-herpesvirus, the human cytomegalovirus (HCMV), has not yet been proven in human cancer, even though recent findings have suggested its potential role in the development of CD4⁺ large granular lymphocyte (LGL) lymphocytosis. Here, we review the current knowledge on the pathogenetic role of HHV-8 and human β-herpesviruses in human lymphoproliferative disorders.

Evolution of human herpesvirus type 8-associated gastric Kaposi's sarcoma following corticosteroid treatment for asthma

The association of gastric Kaposi's sarcoma (KS) with human herpesvirus type 8 (HHV-8) may be found in immunosuppressed patients such as those with AIDS or transplant recipients. A 64-year-old man with a 2-year history of corticosteroid treatment was admitted due to the impression of chronic obstructive pulmonary disease with secondary infection. Abdominal fullness and tarry stool led to the performance of panendoscopy, which revealed two hypertrophic gastric mucosal lesions. These lesions had transformed into a large polyp 2 months later. KS was not diagnosed until a third endoscopic biopsy was performed. The polyp further transformed into a flattened, elongated tumor within a month. The patient died from acute cardiopulmonary insufficiency 4 days after radical gastrectomy. Polymerase chain reaction study identified HHV-8 in all biopsied specimens and resected tumor lesions. Immunostaining further demonstrated the virus in the tumor cells. Both of these methods seemed more sensitive in diagnosing KS than histologic examination of small biopsied specimens. This case suggests the existence of a relationship between gastric KS and HHV-8 infection.

Detection of polyomavirus BK and JC in children with kidney diseases and renal transplant recipients

BACKGROUND

Reactivation of polyomavirus is a known reason for severe renal dysfunction in adult renal transplant recipients. Testing for polyomavirus DNA in plasma has been described as a sensitive and specific method to discover viral nephropathy in adult patients. We were now interested in polyomavirus status in a pediatric patient setting.

METHODS

Plasma and urine samples were obtained from 80 children including 38 children after renal transplantation (group 1), 7 children with different kidney diseases receiving immunosuppressive treatment (group 2) and 35 children with different kidney diseases not receiving immunosuppressive treatment (group 3). A nested polymerase chain reaction method was used for amplification of polyomavirus DNA fragments. Differentiation between JC and BK virus was done by digestion with restriction endonucleases.

RESULTS

Polyomavirus DNA was detected in the urine sample of 19 of 38 (50%) renal transplant recipients (group 1), of 1 of 7 (14%) patients from group 2 and in none of the 35 patients of group 3. Plasma samples from 3 (8%) of group 1 patients and from 1 child each of group 2 (14%) and group 3 (3%) were tested positive for polyomavirus DNA.

CONCLUSION

Urinary polyomavirus excretion seems to be more frequent in pediatric patients with kidney diseases receiving immunosuppressive treatment and after renal transplantation than in children with various kidney diseases without immunosuppressive treatment.

Kaposi's sarcoma-associated herpesvirus: clinical, diagnostic, and epidemiological aspects

Kaposi's sarcoma-associated herpesvirus (KSHI) is one of the few viruses proven to be associated with tumorigenesis in humans. Its causal association with all clinical and epidemiological variants of Kaposi's sarcoma (KS) is well established. KSHV is also involved in the pathogenesis of primary effusion lymphoma (PEL) and a subset of multicentric Castleman's disease (MCD). Possible associations of KSHV with other clinical settings have been extensively examined. The findings from several of these studies are contradictory and are yet to be resolved. Concentrated effort over the last decade, since the initial discovery of KSHV, led to the development of several experimental systems that resulted in a better comprehension of the biological characteristics of KSHV and set the stage for the understanding of mechainisms by which diseases are induced by the virus. The development of molecular, histological, and serological tools for KSHV diagnosis allowed researchers to track the transmission and to study the epidemiology of KSHV. These assays have been applied, in particular in ambiguous cases, in order to confirm clinically and pathologically based diagnoses. Here, we review the advances in the clinical, experimental, diagnostic, and epidemiological research of KSHV.

Immunohistochemical and molecular assessment of human herpesvirus type 8 in gastrointestinal tumours

BACKGROUND

Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal tumours of the gastrointestinal tract, histologically identified as highly cellular spindle or epithelioid cell tumours, and often positive for CD34 (60-70%). Kaposi's sarcomas (KSs) are similar to GISTs: they are most often found in the gastrointestinal tract (although cutaneous lesions do occur), they are also composed of spindle or epithelioid cells (although erythrocytes are also seen), and the tumour cells are nearly all positive for CD34. Human herpesvirus type 8 (HHV-8) DNA has been found consistently in all types of KS, in particular in CD34 positive KS tumour cells. However, the association between HHV-8 and GIST has not been investigated.

AIMS

To assess the presence of HHV-8 in GISTs.

METHODS

Paraffin wax embedded tissues of 86 primary GISTs and their recurrent or metastatic tumours were analysed immunohistochemically for the CD34 antigen and HHV-8 latent nuclear antigen 1 (LNA-1) and by means of the nested polymerase chain reaction (PCR) and real time PCR for HHV-8 DNA.

RESULTS

None of the 86 GISTs contained HHV-8 DNA sequences or LNA-1 positive cells.

CONCLUSIONS

These results demonstrate the lack of HHV-8 infection in GIST tumour cells. HHV-8 does not appear to play a role in the pathogenesis of GIST, irrespective of the status of the tumour.

Resolution of lymphocytic interstitial pneumonia in a human immunodeficiency virus-infected adult following the start of highly active antiretroviral therapy

A case of human immunodeficiency virus (HIV)-associated lymphocytic interstitial pneumonia is described, in which improvement occurred soon after starting antiviral therapy. A 20-y-old black female with HIV infection (CD4+ count 228 x 10(6) cells and plasma viral load 379,670 copies/ml) showed radiological signs of reticulonodular infiltrates of the lungs and pulmonary functional tests indicative of a severe restrictive syndrome. Bronchoalveolar and blood cultures yielded no organism and transbronchial biopsy disclosed findings consistent with lymphocytic interstitial pneumonia. After 4 weeks on triple HIV combination therapy, she was well and respiratory tests had normalized. Six months later, a computed tomographic scan of the chest showed only residual alterations. Despite a good sirological response to treatment, no significant immune recovery occurred over a 2 y follow-up.

Maintenance of gammaherpesvirus latency requires viral cyclin in the absence of B lymphocytes

Gammaherpesviruses establish a life-long chronic infection that is tightly controlled by the host immune response. We previously demonstrated that viruses lacking the gammaherpesvirus 68 (gammaHV68) viral cyclin (v-cyclin) exhibited a severe defect in reactivation from latency and persistent replication. In this analysis of chronic infection, we demonstrate that the v-cyclin is required for gammaHV68-associated mortality in B-cell-deficient mice. Furthermore, we identify the v-cyclin as the first gene product required for maintenance of gammaherpesvirus latency in vivo in the absence of B lymphocytes. While the v-cyclin was necessary for maintenance of latency in the absence of B cells, maintenance of v-cyclin-deficient viruses was equivalent to that of wild-type gammaHV68 in the presence of B cells. These results support a model in which maintenance of chronic gammaHV68 infection requires v-cyclin-dependent reactivation and reseeding of non-B-cell latency reservoirs in the absence of B cells and raise the possibility that B cells represent a long-lived latency reservoir maintained independently of reactivation. These results highlight distinct mechanisms for the maintenance of chronic infection in immunocompetent and B-cell-deficient mice and suggest that the different latency reservoirs have distinct gene requirements for the maintenance of latency.

Spectrum of Kaposi's sarcoma-associated herpesvirus, or human herpesvirus 8, diseases

Human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus (KSHV), discovered in 1994, is a human rhadinovirus (gamma-2 herpesvirus). Unlike other human herpesviruses (herpes simplex virus, Epstein-Barr virus, varicella-zoster virus, cytomegalovirus, HHV-6, and HHV-7), it is not widespread in the general population and has many unique proteins. HHV-8 is strongly associated with all subtypes of Kaposi's sarcoma (KS), multicentric Castleman's disease, and a rare form of B-cell lymphoma, primary effusion lymphoma. In addition, HHV-8 DNA sequences have been found in association with other diseases, but the role of the virus in these diseases is largely unconfirmed and remains controversial. The seroprevalence of HHV-8, based on detection of latent and lytic proteins, is 2 to 5% in healthy donors except in certain geographic areas where the virus is endemic, 80 to 95% in classic KS patients, and 40 to 50% in HIV-1 patients without KS. This virus can be transmitted both sexually and through body fluids (e.g., saliva and blood). HHV-8 is a transforming virus, as evidenced by its presence in human malignancies, by the in vitro transforming properties of several of its viral genes, and by its ability to transform some primary cells in culture. It is not, however, sufficient for transformation, and other cofactors such as immunosuppressive cytokines are involved in the development of HHV-8-associated malignancies. In this article, we review the biology, molecular virology, epidemiology, transmission, detection methods, pathogenesis, and antiviral therapy of this newly discovered human herpesvirus.