Spontaneously regressed Kaposi's sarcoma and human herpesvirus 8 infection in a human immunodeficiency virus-negative patient

Kaposi's sarcoma occurring in a 78-year-old woman, with the absence of the human immunodeficiency virus infection, was correctly diagnosed by immunohistochemistry using anti-human herpesvirus 8 (HHV8) antibody (PA1-73N) for the first time. The patient suffered from chronic respiratory failure and was treated with a low dose of steroids for 2.5 years. After her medication dosage was increased for the exacerbation of the respiratory failure, multiple skin tumors in her feet and legs suddenly developed. Histopathologically, skin tumors were suspected as Kaposi's sarcoma at the first biopsy and reactive angiomatosis at the second biopsy. Polymerase chain reaction and immunohistochemistry, however, revealed the presence of HHV8 DNA fragment and positive staining in the majority of spindle cells in the skin tumors. Serological examination confirmed the positivity of anti-HHV8 antibodies. HHV8 infection and steroid-induced immunosuppression, as well as environmental factors played a role in the development of Kaposi's sarcoma in this patient, because she was born in Okinawa, which is a well-known endemic area of Kaposi's sarcoma in Japan. As her general condition improved, the skin lesions regressed without any specific treatment, and disappeared completely 8 months later, in which regression may be associated with evidence of numerous CD8 cell infiltration in the second biopsy tissues. No recurrence was observed during the following 6 month follow up.     

Infection of a human retinal pigment epithelial cell line with human herpesvirus 6 variant A

A retinal pigment epithelial (RPE) cell line (K-1034) was examined for its susceptibility to human herpesvirus 6 variant A (HHV-6A). Exposure of K-1034 cells to HHV-6A induced the formation of multinucleated giant cells, which was suppressed by an inhibitor of viral DNA synthesis. In the giant cells, herpesvirus nucleocapsids were demonstrated by electron microscopy and the viral glycoprotein B was detected by immunofluorescence assay. These results indicate that K-1034 cells are susceptible to HHV-6A and suggest that HHV-6A has an ability to directly destroy epithelial cells. J. Med. Virol. 53:105–110, 1997. © 1997 Wiley-Liss, Inc.     

心脏移植并发疱疹病毒6型感染

从１３例心脏移植病人的外周血淋巴细胞中分离出２株疱疹病毒６型（ＨＨＶ６），并检测了手术前后病人血清特异性抗－ＨＨＶ６ＩｇＧ抗体。这２株ＨＨＶ６可引起典型的细胞病变。分离的毒株在电镜下可见疱疹类病毒样颗粒。经特异性抗体和ＤＮＡ杂交试验证明，这两株病毒均属于ＨＨＶ６Ｂ组。病人血清中特异性抗－ＨＨＶ６ＩｇＧ抗体出现４倍或４倍以上增长的有５例（３９％），其中包括２例病毒分离阳性的病人血清。由于病人在术前血清已是阳性和术后出现有意义效价的增长，因此试验结果提示心脏移植前后免疫抑制剂的应用可能是造成ＨＨＶ６复发感染的重要原因。     

Anorectal melanomas do not harbour the Kaposi sarcoma-associated human herpesvirus type 8 DNA

Anorectal melanomas are similar to cutaneous melanomas with regard to the mode of spread and to the immunophenotype. When compared with patients with cutaneous melanoma, those suffering from anorectal melanoma have a much worse outcome. The etiology of anorectal melanomas is as yet completely unknown. For anatomical reasons, ultra-violet (UV-B) radiation can not cause anorectal melanomas as in cutaneous tumours, that are associated with exposure of the skin to UV-B radiation. As the cytokine interleukin-6 (IL-6) is known to stimulate melanoma tumour cell proliferation and a functional homologue of human IL-6 has been identified recently in the HHV-8 genome, this tumorigenic virus might be involved in the pathogenesis of anorectal melanomas. Twelve formalin fixed and paraffin embedded primary anorectal melanomas from seven female and five male patients with a mean age at diagnosis of 71 years (range 38-88 years) were investigated for the presence of HHV-8 DNA. Using a specific and highly sensitive polymerase chain reaction protocol, this tumorigenic gamma-herpesvirus was not detectable in any tumour. This data indicates that HHV-8 is not involved in the development of anorectal melanomas.     

Frequent shedding of human herpesvirus 6 in saliva

We have previously reported the isolation of HHV-6 from saliva samples. Because these isolations were made in PHA-stimulated lymphocytes from healthy adults, which may occasionally contain endogenous HHV-6, it was desirable to repeat this work using cord blood lymphocytes. In this study 18 isolations of viruses provisionally characterized as HHV-6 were made from 19 saliva samples by centrifugally enhanced inoculation into PHA-stimulated cord blood lymphocytes. HHV-6 was not found in 10 pernasal aspirates, 50 endocervical swabs, or 30 male urethral swabs. It is concluded that HHV-6 is usually present in the saliva of most adults and that this affords a possible explanation of the high infection rate with this virus in young children.     

Search for human herpesvirus 6 and human cytomegalovirus in bronchoalveolar lavage from patients with human immunodeficiency virus-1 and respiratory disorders

Virus isolation and viral DNA detection by the polymerase chain reaction were used to investigate the presence of human herpesvirus 6 (HHV-6) and human cytomegalovirus (HCMV) in bronchoalveolar lavage from 34 human immunodeficiency virus-1 (HIV-1)-infected patients with respiratory disorders. The aim was to assess the presence of reactivated HHV-6 in lung tissues for a subsequent evaluation of the frequency of virus involvement in respiratory clinical manifestations in the course of HIV-1 infection. Bronchoalveolar lavage samples were tested for the presence of HCMV, as a routine investigation within a protocol monitoring opportunistic infections in symptomatic HIV-1 patients. Whereas HCMV DNA was detected by the polymerase chain reaction in 12 bronchoalveolar lavage specimens, 10 of which were also positive for virus isolation, all samples were negative for HHV-6 by both virological procedures. The HHV-6 DNA finding in bronchoalveolar lavage from an HIV-1-seronegative patient with renal carcinoma, investigated accidentally together with the bronchoalveolar lavage specimens from HIV-1 seropositive patients, stressed the HHV-6 polymerase chain reaction-negative results in the bronchoalveolar lavage samples under study. It is concluded that the lung may be a target organ for HCMV infection in HIV-1-seropositive patients affected by respiratory symptoms but that this does not seem to be the case for HHV-6. © 1996 Wiley-Liss, Inc.     

Concurrent detection of human herpesvirus type 6 and measles-specific IgMs during acute exanthematic human parvovirus B19 infection

A familial outbreak of human parvovirus B19 infection is described in which serological tests carried out routinely for determining the causal agent of febrile rashes of viral etiology failed to yield a definitive diagnosis. Concurrent detection of serum IgMs to parvovirus B19 and to heterologous viruses such as human herpesvirus type 6 (HHV-6) and measles virus complicated interpretation of the data. IgG avidity tests and investigation and testing for the presence of viral DNA in sera by PCR were required to confirm parvovirus B19. The study stresses the importance of avidity and PCR tests to obtain a firm diagnosis of febrile exanthematic viral diseases.     

Case report: human herpesvirus 6 reactivation associated with colitis in a lung transplant recipient

Whereas human herpesvirus 6 (HHV-6) reactivation is frequent in solid organ transplant recipients, symptomatic disease is rare. A case of colitis associated with HHV-6B reactivation was observed in a lung transplant recipient. This case report suggests that symptomatic HHV-6 infection may occur in the absence of detectable viremia.     

Specific CD8+ T cells recognize human herpesvirus 6B

The importance of human herpesvirus 6 (HHV‐6) species as human pathogens is increasingly appreciated. However, we do not understand how infection is controlled in healthy virus carriers, and why control fails in patients with disease. Other persistent viruses are under continuous surveillance by antigen‐specific T cells, and specific T‐cell repertoires have been well characterized for some of them. In contrast, knowledge on HHV‐6‐specific T‐cell responses is limited, and missing for CD8⁺ T cells. Here we identify CD8⁺ T‐cell responses to HHV‐6B, the most widespread HHV‐6 species, in healthy virus carriers. HHV‐6B‐specific CD8⁺ T‐cell lines and clones recognized HLA‐A2‐restricted peptides from the viral structural proteins U54 and U11, and displayed various antigen‐specific antiviral effector functions. These CD8⁺ T cells specifically recognized HHV‐6B‐infected primary CD4⁺ T cells in an HLA‐restricted manner, produced antiviral cytokines, and killed infected cells, whereas HHV‐6A‐infected cells were not recognized. Thus, HHV‐6B‐specific CD8⁺ T cells are likely to contribute to control of infection, overcoming the immunomodulatory effects exerted by the virus. Potentially, HHV‐6‐associated disease could be addressed by active or passive immunotherapy that reconstitutes virus‐specific CD8⁺ T‐cell responses.     

Detection of human herpesvirus 8 DNA sequences in peripheral blood mononuclear cells of children

Human herpesvirus 8 (HHV-8) DNA sequences were examined in peripheral blood mononuclear cell (PBMC) DNA samples of 56 children, 15 healthy adults, and 10 renal transplant patients by the polymerase chain reaction (PCR). The PCR amplification was carried out using the published KS330₂₃₃ primer pairs to amplify HHV-8 DNA sequences. The PCR-amplified products were confirmed by Southern blot hybridization with radiolabeled 233 bp HHV-8 DNA fragment, which was cloned and sequenced from the PCR-amplified product of Kaposi's sarcoma tissue. Six PCR-amplified product of four children and two renal transplant patients were cloned and sequenced. HHV-8 DNA sequences were detected in 36 of 56 (64%) normal children, in 12 of 15 (80%) healthy adults, and in all 10 renal transplant patients by Southern blot hybridization of PCR-amplified products. Six PCR-amplified products were confirmed by sequencing. These results suggest that HHV-8 infection is prevalent in the Japanese population with infection occurring in early childhood. J. Med. Virol. 53:81–84, 1997. © 1997 Wiley-Liss, Inc.     

Vitreous fluid sampling and viral genome detection for the diagnosis of viral retinitis in patients with AIDS

Cytomegalovirus (CMV) causes severe necrotizing retinitis in patients with the acquired immune deficiency syndrome (AIDS) and other herpesviruses have been implicated in the acute retinal necrosis syndrome (ARN), seen in both the immunocompetent and the immunosuppressed. At present the diagnosis of viral retinitis relies solely on clinical appearances. In order to assess whether the detection of herpesvirus-specific DNA in cell-free vitreous biopsy samples could be useful in the early diagnosis of viral retinitis, vitreous fluid samples were taken from 100 patients. Fifty patients had AIDS as defined by the Centers for Disease Control, (MMWR 36 (suppl 1S):1S–15S, 1987) and retinal disease. The remainder were not known to be HIV infected and had no clinical evidence of retinal infection. Each sample was tested for the presence of CMV, herpes simplex virus 1 (HSV-1), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), and human herpesvirus 6 (HHV6), by amplification of viral DNA using a sensitive and specific nested poly-merase chain reaction (PCR). The presence of detectable CMV or VZV DNA was clearly associated with clinical disease whereas the presence of HSV-1, EBV, and HHV6 sequences were not. Clinical discrimination between CMV- and VZV-associated retinitis was greatly enhanced when the PCR results were taken into consideration. © 1994 Wiley-Liss, Inc.     

Correlation between the detection of viral DNA by the polymerase chain reaction in peripheral blood leukocytes and serological responses to human herpesvirus 6, human herpesvirus 7, and cytomegalovirus in renal allograft recipients

Diagnosis of significant infections by human herpesvirus 6 (HHV6) and 7 (HHV7) in transplant patients has proved difficult because both viruses are ubiquitous and can cause persistent infections in their hosts. The significance of viral DNA detected in peripheral blood leukocytes (PBLs; DNAemia) by PCR is therefore unclear. The interpretation of serological results is complicated by the fact that both primary and secondary infections with other herpesviruses may be associated with a concurrent antibody response to HHV6. Fifty-four renal allograft recipients were studied prospectively and their serological response to HHV6, HHV7 and CMV were compared with the detection of viral DNAemia from the homologous and heterologous viruses. Serum and heparinised blood samples were collected prospectively from 54 renal allograft recipients. DNA was extracted from PBLs and tested for the presence of HHV6, HHV7 and CMV DNA by PCR. Antibodies to HHV6 and HHV7 were measured by an indirect immunofluorescence test and to CMV by an anticomplement immunofluorescence (ACIF) test. CMV IgM antibodies were detected by a commercial enzyme immunoassay. CMV and HHV7 DNAemia were each significantly associated with serological responses to the homologous virus but no such association was found for HHV6 DNAemia. However, patients with consecutively positive DNAemia to any of the viruses (including HHV6) were more likely to have a homologous serological response. Patients who had detectable CMV IgM without a concurrent rise in CMV antibodies were significantly less likely to have CMV DNAemia (odds ratio = 0.16; 95% CI 0.02–0.9). CMV IgM antibodies may be associated with HHV6 or HHV7 DNAemia (odds ratio 2.3; 95% CI 0.5–15). This serological profile may reflect a cross-reactive response to HHV6, HHV7 or other herpesviruses. CMV IgM should not be used in isolation for the diagnosis of CMV infection or disease in this group of patients. J. Med. Virol. 53:288–294, 1997. © 1997 Wiley-Liss, Inc.     

The evidence of human herpesvirus 6 infection in the lymph nodes of Hodgkin's disease

Human herpesvirus 6 (HHV-6), the causative agent of exanthem subitum, has been implicated in other diseases. Recently HHV-6-specific sequences have been detected by Southern blot analysis and polymerase chain reaction in the lymph nodes of three patients with Hodgkin's disease. The pathological localization of HHV-6, however, is still unknown. In order to study the pathological role of HHV-6 in Hodgkin's disease, we investigated, by immunohistochemical and molecular methods, two lymph node biopsies taken from a 7-year-old boy with Hodgkin's disease during the course of disease evolution. Although the histopathological findings of the first biopsy differed from those of the second, HHV-6 antigens and sequences could be detected in both lymph nodes by immunohistochemistry and in situ hybridization, respectively. HHV-6 was localized in macrophages, predominantly in lymphoid follicles, but not in ReedSternberg cells. Antibody titres to HHV-6 were consistent with reactivation of latency. Neither cytomegalovirus nor Epstein-Barr virus was present. Our data suggest a role for HHV-6 in the pathogenesis of Hodgkin's disease.     

Infection of infants with human herpesvirus type 6 may be associated with reduced allergic sensitization and T‐helper type 2 development

Background Epidemiological studies point to an inverse relationship between microbial exposure and the prevalence of allergic diseases. The underlying mechanism for this observation remains largely unknown, as well as the nature of the microbes involved. Objective To investigate the effects of early infection with human herpesviruses (HHVs) on IgE formation and T‐helper type 2 (Th2) development in infants. Methods Serum was collected from children aged 18 months and assessed for IgE to common allergens and IgG to five common herpesviruses. Cord blood plasmacytoid dendritic cells (pDC) were exposed to HHV type 6 in vitro and mixed with allogeneic cord blood CD4⁺ T cells. Cytokine levels were determined by ELISA and by flow cytometry. Results We found that children seropositive at 18 months of age to HHV type 6 were significantly less often IgE sensitized than seronegative children [odds ratio (OR): 0.08, 95% confidence interval (CI): 0.009–0.68]. HHV type 6 also decreased the production of the Th2‐associated cytokines IL‐5 and IL‐13 by CD4⁺ T cells when co‐cultured with allogeneic cord blood pDC. This was associated with an increased production of IFN‐α by pDC exposed to HHV type 6. Conclusion These data indicate that an early childhood infection with HHV type 6 could down‐regulate Th2 responses and reduce IgE formation to common allergens in a young child.     

Suppressive effects of human herpesvirus 6 on in vitro colony formation of hematopoietic progenitor cells

Human herpesvirus 6 (HHV-6) has been reported to be involved in bone marrow failure after bone marrow transplantation (BMT). To elucidate the role of HHV-6 in the marrow failure, we examined the comparative effect of two variants of HHV-6 (HHV-6A and HHV-6B) and human herpesvirus 7 (HHV-7) on in vitro colony formation of hematopoietic progenitor cells in methylcellulose semi-solid media. Progenitor cells prepared from cord blood mononuclear cells (CBMNCs) were infected with one of these viruses at various multiplicity of infection (MOI), and were subjected to methylcellulose colony assay. Formation of both granulocyte/macrophage (CFU-GM) and erythroid (BFU-E) colonies was MOI-dependently suppressed after infection with the Z29 strain of HHV-6B. Although HHV-6A suppressed the formation of BFU-E colonies as efficiently as HHV-6B, the former did not exhibit significant suppressive effect on the formation of CFU-GM colonies at an MOI 1. HHV-7 had no effect on hematopoietic colony formation at all. Based on frequent positivity of viral DNA in single colonies obtained from HHV-6-infected progenitor cells by polymerase chain reaction and in situ hybridization, direct effects of HHV-6 on the hematopoietic progenitor cells are suggested as the cause of the suppression rather than indirect effects via accessory cells of the bone marrow. J. Med. Virol. 52:406–412, 1997. © 1997 Wiley-Liss, Inc.     

人疱疹病毒6型感染与神经胶质瘤关系的初步研究

目的探讨人疱疹病毒6型（human herpesvirus-6,HHV-6）感染与神经胶质瘤的关系。方法将辽宁省肿瘤医院神经外科2011年6月-2013年5月收治的神经胶质瘤患者45例纳入病例组,将同期该医院收治且已排除神经胶质瘤的脑外伤患者45例作为对照组。分别采用巢式聚合酶链式反应（nested polymerase chain reaction,Nested—PCR）法检测两组研究对象人病变脑组织样本中HHV-6序列;采用免疫组化染色法检测两组研究对象人病变脑组织样本中HHV-6抗原的表达。结果病例组HHV石DNA阳性率为31．11％,对照组HHV-6DNA阳性率为6．67％（χ2=8．755,P=0．003）。病例组HHV-6早期抗原041表达阳性率为22．22％,对照组HHV-6早期抗原p41表达阳性率为0．00％（χ2=11．250,P=0．001）。病例组HHV-6DNA阳性率、HHV-6抗原阳性率均高于对照组,组间差异有统计学意义（P〈0．05）。结论神经胶质瘤患者和非神经胶质瘤脑外伤患者病变脑组织中HHV石感染率有差异,据此推断HHV-6感染在神经胶质瘤的发生和发展过程中起到一定的作用。     

Case report: primary human herpesvirus-6 associated with an afebrile seizure in a 3-week-old infant.

We describe a 3-week-old male infant with an afebrile seizure in whom serologic and polymerase chain reaction (PCR) findings support concomitant primary human herpesvirus 6 (HHV-6) infection. Although HHV-6 infection has been associated with first-time febrile seizures and encephalitis in both immunocompetent and immunocompromised hosts, it has not been associated previously with afebrile seizures in healthy infants. This report provides additional evidence of the neuropathogenic potential of HHV-6.     

A serological investigation of human herpesvirus 6 infections in liver transplant recipients and the detection of cross-reacting antibodies to cytomegalovirus.

Sera from 50 orthotopic liver transplant recipients were examined for antibodies to human herpesvirus 6 (HHV-6) and cytomegalovirus (CMV), and the findings correlated with the clinical condition of the patients. Both primary and secondary HHV-6 infections were detected serologically following liver transplantation. Interpretation of serological assays is complicated by CMV and HHV-6 antibody cross reactions which were common. Sera from 5 patients became HHV-6 antibody negative following absorption with CMV infected cells. Thirty patients were initially seronegative for HHV-6 antibodies, 12 remained so following transplantation, 5 developed cross reacting antibodies, and 13 seroconverted. The seroconversions occurred at 4 to 8 weeks post-transplant in the same time period as CMV antibody rises. HHV-6 IgM was detected in only 4 of the 13. Of the 7 patients who had serological evidence of active HHV-6 infections but no evidence of CMV infection, 4 (56%) had fever, 1 (14%) hepatitis, 1 (14%) lung dysfunction, and 3 (42%) neurological disorders. In the 12 patients who remained HHV-6 antibody negative, there were fewer fevers and neurological disorders.