Yasmin Ench

Characterization of natural Epstein-Barr virus infection and replication in smooth muscle cells from a leiomyosarcoma

Cells from a leiomyosarcoma tumor (LMS‐1) from a patient with the acquired immunodeficiency syndrome (AIDS) were explanted, cultured in vitro, and studied by phase‐contrast microscopy for morphologic and growth characteristics, immunostaining for cell markers, EBER in situ hybridization and polymerase chain reaction for detection of Epstein‐Barr virus (EBV), and immunostaining for expression of EBV antigens. The cells exhibited very slow growth in vitro, with unusual elliptical and spindle‐shaped morphology and fragmentation of the cytoplasm into long, tapering, cytoplasmic processes. Greater than 90% of cells expressed diffuse distribution of the smooth muscle isoform of actin by immunoperoxidase staining. Approximately 25% of cells expressed very bright fluorescence by immunostaining of the smooth muscle isoforms of calponin and actin. The majority of cells demonstrated a weak signal for CD21; approximately 5–10% of cells showed a strong signal that was confined to cell surfaces. The cultured cells harbored EBV, and infectious EBV continued to be detected by polymerase chain reaction and virus culture through several passages in vitro. Several EBV antigens were expressed, including latent antigen EBNA‐1, immediate‐early antigen BZLF1, early antigen EA‐D, and late antigens, including viral capsid antigen p160, gp125, and membrane antigen gp350. Human umbilical cord lymphocytes that were transformed with virus isolated from cultured cells yielded immortalized cell lines that expressed EBV antigens similar to other EBV‐transformed lymphocyte cell lines. These results confirm that EBV is capable of lytic infection of smooth muscle cells with expression of a repertoire of latent and replicative viral products and production of infectious virus. EBV infection of smooth muscle cells may contribute to the oncogenesis of leiomyosarcomas. J. Med. Virol. 57:36–46, 1999.

Epidemiology of Herpesvirus Papio Infection in a Large Captive Baboon Colony: Similarities to Epstein-Barr Virus Infection in Humans

The epidemiology of herpesvirus papio, a lymphocryptovirus similar to Epstein-Barr virus (EBV), was studied in a captive colony of >1900 baboons. Herpesvirus papio IgG antibody titers were measured by IFA. In total, 438 specimens from 296 baboons were assessed, including 116 serial specimens from 52 juveniles and 6 infants studied monthly for 1 year following birth and at age 18 months. Maternally derived antibody reached a nadir at 4 months of age. About 75% of animals at 12 months of age and >95% of animals after age 24 months demonstrated serologic evidence of herpesvirus papio infection. After age 3 years, the geometric mean titer was 1:60-75. The epidemiology of herpesvirus papio infection in baboons closely parallels that of EBV infection in humans. An animal model of lymphocryptovirus infection will facilitate investigations of human lymphocryptovirus biology.

CHILDHOOD INFECTIOUS MONONUCLEOSIS NOT ASSOCIATED WITH EPSTEIN-BARR VIRUS

Non-Epstein-Barr Virus (EBV) induced infectious mononucleosis (IM) has not been adequately studied in children. In a prospective evaluation of 171 children with an illness characterized by clinical and hematologic findings for IM, 19 (11%) children had their episode unassociated with an acute EBV infection. The majority of children with non-EBV IM were <4 years old, 11 (58%), and males, 11 (58%). The spectrum of clinical manifestations in general were similar to that reported for EBV-IM in children except for a decreased rate of exudative tonsillitis in the non-EBV group, 5 (26%). Transient respiratory or hematologic complications developed in 2 children. Liver transaminases were elevated acutely and transiently in 6/10 children tested. Typical heterophil antibody responses were not detected. EBV testing indicated that 6 children had experienced this infection in the distant past; the infection in two others was of inconclusive onset. A suspected etiology was identified in 5 children: 3 had significant IgG antibody titer rises to cytomegalovirus (2 of these had the virus isolated from the urine) and 2 others had significant titer rises to Toxoplasma gondii. Children with non-EBV IM tended to be younger than that reported with EBV-IM. The non-EBV IM subgroup with suspected etiology appeared to be a major contributor to the low frequency of exudative tonsillitis. Reactivation of an EBV-carrier state provoked by the intervening etiologic agent was not documented as has been reported in adults. The majority of non-EBV IM episodes in children remains of unknown etiology.

Processing of voided urine for prostate cancer RNA biomarker analysis.

Voided urine samples have been shown to contain cells released from prostate tumors. Could good quality RNA from cells in urine be obtained from every donor for multimarker analysis? In addition, could urine donation be as simple as possible, a practical consideration for a lab test, without involving a prostate massage (as indicated for PCA3 testing), which precludes frequent collection; needing it done at a specific time of day (e.g., first or second urine); and requiring prompt processing of samples in clinics with limited molecular biology capability?

Epstein-Barr Virus Infection in Families with a Childhood Index Case of Infectious Mononucleosis

Epstein-Barr virus (EBV) infectious mononucleosis (IM) and even subclinical EBV infections have traditionally been reported to occur uncommonly among intimate contacts of an index case (1). Yet EBV infections must spread efficiently because most children become infected early in life (2). The present study addressed inconsistencies on transmission patterns of EBV in prior reports by prospectively evaluating families with a childhood index case of EBV-IM.

1170 PROLONGED OROPHARYNGEAL EXCRETION OF EPSTEIN-BARR VIRUS FROM CHILDREN AFTER INFECTIOUS MONONUCLEOSIS

The duration of oropharyngeal excretion of Epstein-Barr virus (EBV) in children following an episode of EBV-induced infectious mononucleosis (IM) has not been reported. In the present study children with clinical, hematologic, and viral-specific serologic findings of EBV-IM were evaluated prospectively for oropharyngeal excretion of EBV. Viral isolation was determined by transformation and induction of EBV-nuclear antigen in umbilical cord lymphocyte cultures inoculated with oropharyngeal secretions. Seventy-five (74.3%) of 101 study children examined during the initial 3 weeks after clinical onset were positive for oropharyngeal EBV. Followup examinations at 4-8 week, 9-28 week, and 29-34 weeks revealed the presence of oropharyngeal EBV in 21 (55.3%) of 38, 19 (50.0%) of 38, and 13 (61.9%) of 21 children tested, respectively. The only significant difference in excretion rates with time was between the intervals 0-3 weeks and 9-28 weeks (p <.01). There was no difference in prevalence of EBV excretion related to age or serologic findings. The role that this long-term viral excretion has in the transmission of EBV remains to be elucidated.

819 SEROLOGIC AND VIROLOGIC STUDIES OF EPSTEIN-BARR VIRUS INFECTIONS IN CHILDREN WITH AN INFECTIOUS MONONUCLEOSIS (IM) -LIKE DISEASE

Few data are available about the antibody response to Epstein-Barr virus(EBV) and the rate of isolation of this virus in children with an IM-like disease. Twenty-five children presenting with a clinical picture suggesting this diagnosis are the subject of this report. Fourteen children were 4 mo to 5 yrs of age, eleven were 6 to 16 yrs. High antibody(IgG) titers(>160) to viral capsid antigen of EBV were detected in the sera of 15(60%.) of the children. Antibodies to early antigen, predominately to the diffuse component, were found in 22(88%). Specific IgM to EBV was detected in 17(81%) of 21 childrens sera examined. The initial sera of 14(56%) children contained antibodies to viral capsid antigen but lacked antibodies to nuclear antigen of EBV. The latter was further evidence of a primary EBV infection. EBV was isolated from the oropharynx in 12(63%) of 19 children tested. Children <3 yrs of age tended to lack IM-associated heterophile antibodies and have a higher rate of antibodies to restricted component of early antigen than the older group. Two children 4 mo and 2 yrs old, probably did not have an EBV-induced disease. The type and duration of the immune response and the rate and duration of EBV isolation were roughly similar to that noted in adults with EBV-induced IM. EBV specific serologic and virologic cesting is a valuable diagnostic aid particularly when the heterophile antibody test is negative, early or throughout the course of IM, or the clinical presentation is atypical.