Motohiko Okano

Epstein-Barr virus and human diseases: recent advances in diagnosis.

Since the discovery of Epstein-Barr virus (EBV) from a cultured Burkitts lymphoma cell line in 1964, the virus has been associated with Burkitts lymphoma, nasopharyngeal carcinoma, and infectious mononucleosis. During the recent decade, EBV has been etiologically implicated in a broad spectrum of human diseases. The precise role of this virus in these diseases is not well understood, but clearly, defective immunosurveillance against the virus may permit an uncontrolled proliferation of EBV-infected cells. As a result, a growing number of cases of EBV-associated B-cell proliferative diseases or lymphoma have been noted in patients with primary and acquired immunodeficiencies. These lymphoproliferative diseases and others, such as chronic mononucleosis syndrome, are leading to new areas of investigation which are providing information regarding the pathogenetic mechanisms of EBV-induced diseases. The early accurate diagnosis of EBV infection can be achieved by performing EBV-specific serology, detecting for EBV-determined nuclear antigen in tissues, establishing spontaneous lymphoid cell lines, and using molecular hybridization techniques for demonstrating the presence of viral genome in affected lesions. Images

Severe chronic active Epstein-Barr virus infection syndrome.

Reports of unusually severe lymphoproliferative disorders associated with extremely high antibody titers against Epstein-Barr virus (EBV) have recently increased. The syndrome, which we designated severe chronic active EBV infection syndrome, is characterized by persistent or intermittent fever, lymphadenopathy, and hepatosplenomegaly and primarily affects children and young adults. Polyclonal gammopathy and bone marrow suppression are generally observed, and some patients develop B-cell or T-cell lymphoproliferation or lymphoma. Frequently, EBV genomes are detectable in tissues infiltrated with lymphoid cells. Additionally, it is difficult to establish spontaneous or B95-8 EBV-induced cell lines despite the expression of an activated EBV infection. We review and report here the published medical literature and our own experience regarding patients with severe chronic active EBV infection syndrome in an attempt to understand this enigmatic syndrome and the possible pathogenetic mechanism(s) responsible for this disorder.

Novel mutations of FOXP3 in two Japanese patients with immune dysregulation, polyendocrinopathy, enteropathy, X linked syndrome (IPEX)

Editor—Immune dysregulation, polyendocrinopathy, enteropathy, X linked syndrome (IPEX), also known as X linked autoimmunity-allergic dysregulation syndrome (XLAAD), is characterised by enteropathy and involvement of the endocrine system, such as insulin dependent diabetes mellitus (IDDM) and thyroiditis, which develop in association with autoantibodies in early infancy (MIM 304930, 304790).1 2 IPEX has been mapped to chromosome Xp11.23-Xq13.3.3 4 Recent studies have indicated that FOXP3 , a member of forkhead/winged-helix proteins, is a causative gene for both IPEX and an equivalent mouse, scurfy .5-8 Human FOXP3 consists of 11 exons and encodes 431 amino acids containing a zinc finger (Zn) domain, a leucine zipper (Zip) motif, and a forkhead domain.6 8 We have previously reported two unrelated Japanese patients with X linked autoimmune enteropathy associated with tubulonephropathy and endocrinopathy.2 9 10 We report here novel mutations in the FOXP3 gene of these patients. Clinical and laboratory findings of our patients have been previously reported.2 9 10 Briefly, patient 1, a boy, now 11 years old, was diagnosed as having autoimmune …

Epstein-Barr virus infection and its role in the expanding spectrum of human diseases.

Recent advances of the various laboratory tests to detect Epstein‐Barr virus (EBV) infection have clarified the causative role for a spectrum of EBV‐associated diseases. They include lymphoproliferative disorders (LPD), which occur in immunologically compromised individuals, Hodgkins disease (HD), chronic active EBV infection (CAEBV), virus‐associated hemophagocytic syndrome (VAHS), certain forms of T cell lymphoma, and some gastric carcinomas, in addition to the classical EBV‐associated diseases such as EBV genome‐positive Burkitts lymphoma (BL), undifferentiated nasopharyngeal carcinoma (NPC) and infectious mononucleosis (IM). This review intends to introduce the recent progress of studies on EBV infection mainly from the clinical points of view.

Immunovirological studies of fatal infectious mononucleosis in a patient with X-linked lymphoproliferative syndrome treated with intravenous immunoglobulin and interferon-α

We have studied a 19-year-old male with X-linked lymphoproliferative syndrome (XLP) and infectious mononucleosis (IM) who was treated with high-dose immunoglobulin (500 mg/kg/day) and recombinant interferon (IFN)-alpha (2 x 10(6) IU/m2/day). Fulminant hepatitis was delayed; however, virus-associated hemophagocytic syndrome, cholestatic jaundice, and renal failure occurred terminally. Initially, nonspecific natural killer (NK) cell activity against K562 cells was normal but it gradually decreased. Although reactive T cells were markedly increased in his blood during the acute phase, spontaneous EBV-positive cell lines were easily established. Additionally, his mononuclear cells produced IFN-gamma but not IFN-alpha prior to treatment. Based on results of in vitro studies, we conclude that both IFN-alpha and IFN-gamma production are likely necessary for inhibiting EBV immortalization in vitro. Both IFN-alpha and -gamma were produced in cultures of B95-8 EBV-infected mononuclear cells from EBV-seropositive healthy individuals. These results suggest that defective EBV-specific cytotoxic T cell activity accompanied with defective or discordant IFN-alpha and -gamma production permitted the development of fatal IM in this patient. Combined treatment with immunoglobulin and IFN-alpha appeared to be partially effective during the early stage of this disease.

Determination of Carrier Status for the Wiskott-Aldrich Syndrome by Flow Cytometric Analysis of Wiskott-Aldrich Syndrome Protein Expression in Peripheral Blood Mononuclear Cells

The Wiskott-Aldrich syndrome (WAS) is caused by defects in the WAS protein (WASP) gene on the X chromosome. Previous study disclosed that flow cytometric analysis of intracellular WASP expression (FCM-WASP analysis) in lymphocytes was useful for the diagnosis of WAS patients. Lymphocytes from all WAS patients showed WASPdim instead of WASPbright. Here we report that FCM-WASP analysis in monocytes could be a useful tool for the WAS carrier diagnosis. Monocytes from all nine WAS carriers showed varied population of WASPdim together with WASPbright. None of control individuals possessed the WASPdim population. In contrast, lymphocytes from all the carriers except two lacked the WASPdim population. The difference of the WASPdim population in monocytes and lymphocytes observed in WAS carriers suggests that WASP plays a more critical role in the development of lymphocytes than in that of monocytes. The present studies suggest that a skewed X-chromosomal inactivation pattern observed in WAS carrier peripheral blood cells is not fixed at the hemopoietic stem cell level but progresses after the lineage commitment.

Overview and problematic standpoints of severe chronic active Epstein/Barr virus infection syndrome

Epstein-Barr virus (EBV) is an ubiquitous human herpesvirus. Its infection is generally subclinical. However, in certain circumstances, EBV causes infectious mononucleosis (IM) and lymphoproliferative disorders (LPD) in immunologically compromised individuals. Furthermore, EBV infection is etiologically linked to human malignancies such as Burkitts lymphoma (BL), nasopharyngeal carcinoma (NPC) and miscellaneous malignant diseases because of the presence of viral genome in their tumor tissues. Since the late 1970s, a chronic undefined illness possibly associated with EBV infection, named such as severe chronic active EBV infection syndrome (SCAEBV), has been of interest due to its unique manifestations that often result in a poor prognosis. This review is an overview of SCAEBV with respect to its; history, diagnosis, pathogenesis, therapeutic approaches, and ideas on how to further recognize this enigmatic disease.

Interferon-gamma in a family with X-linked lymphoproliferative syndrome with acute Epstein-Barr virus infection

A 20-month-old male with fulminant infectious mononucleosis and the X-linked lymphoproliferative syndrome (XLP) was studied. Epstein-Barr virus (EBV)-determined nuclear antigen (EBNA) and EBV DNA were detected in various tissues. Despite a combined treatment with acyclovir, immunoglobulin, and methylprednisolone, the patient deteriorated rapidly. Following treatment with recombinant interferon-gamma (IFN-γ), defervescence occurred and circulating EBNA-positive cells markedly decreased. IFN-γ prior to treatment ranged from 10.8 to 24.5 U/ml in the patients serum and increased linearly post exogenous IFN-γ treatment. His natural killer (NK)-cell activity remained in the normal range throughout his illness but autologous EBV-infected cells were not killedin vitro by his peripheral blood lymphocytes (PBL). These results suggest that patients with the fatal infectious mononucleosis phenotype of XLP may produce endogenous IFN-γ. Defective cytotoxic T cells against EBV-infected cells seem to be responsible for the fulminant infectious mononucleosis in this patient.

Platelet‐specific hemophagocytosis in a patient with juvenile dermatomyositis

Juvenile dermatomyositis (DM) is an in ̄ammatory disease mainly characterized by erythematous rash and muscular weakness with vasculopathy (1). Although the prognosis of juvenile DM is fair in most cases, severe and rush cases have been reported. Interstitial pneumonia and gastrointestinal bleeding are established fatal complications in both adulthood and juvenile DM. However, reported cases with hematological complication including thrombocytopenia are limited (2). Here, we report a case of severe thrombocytopenia complicated with juvenile DM. Of interest was a ®nding that signi®cant platelet-speci®c hemophagocytosis was observed in the bone marrow.

Enzyme-linked immunosorbent assay (ELISA) for detecting antibodies in sera of patients with adenovirus infection

The 41 distinct antigenic types of adenoviruses (Ads) are responsible for a broad spectrum of diseases in humans. We have developed an enzyme-linked immunosorbent assay (ELISA) using adenovirus (Ad) infected MRC-5 cells for detecting IgG and IgM antibodies to Ads. Using the ELISA, we detected IgG antibodies in 100% (20/20) of sera from normal adults (geometric mean titer, GMT = 1840.8, range = 40-20,480) and IgM antibodies in 3 of 20 sera (15%) with a GMT of 25.1. Our indirect immunofluorescence (IF) technique also detected IgG antibodies in 100% of these sera (GMT = 248.3, range = 40-5,120) and IgM antibodies in the 3 samples reactive in ELISA (GMT = 20.0, range = less than 5-40). In contrast, the complement fixation (CF) test detected antibodies to Ads in only 65% (13/20) of these sera (GMT = 10.9, range = less than 4-32). Moreover, IgG and IgM responses could not be distinguished using CF. Thus the sensitivity of these three techniques is greatest for ELISA. Additionally, a study of sequential sera from 3 patients with acute Ad infection disclosed seroconversion using all three methods. Both the ELISA and IF techniques permit the detection of transition from IgM to IgG, whereas CF only detects conversion from seronegativity to seropositivity. Finally, preliminary data suggest that the IgM response as measured by ELISA is specific for subgroups or types of Ad. This newly devised ELISA may be useful for detecting Ad infections.