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This report describes the results of histopathologic and virologic studies in six patients with undifferentiated carcinoma (malignant lymphoepithelial lesions) of the salivary glands. Epstein-Barr virus (EBV) was detected in tumors from all six patients by DNA hybridization, while adjacent non-tumorous salivary gland tissue was negative for EBV in two patients tested for DNA and in three patients tested for Epstein-Barr nuclear antigen (EBNA). These findings add more evidence that these unusual salivary gland tumors are EBV-associated, and that EBV is specific to the tumor.

Epstein-Barr virus (EBV) carrying biopsies of Burkitt lymphoma (BL) and nasopharyngeal carcinoma (NPC) were used to examine the question whether the EBV-associated nuclear antigen (EBNA) can be demonstrated by the acid fixed nuclear binding (AFNB) technique, developed previously for the demonstration of EBNA in cultured cell lines [11]. Extracts of 5 BL and 5 NPC biopsies gave a brilliant, EBNA specific fluorescence after binding to acid fixed chicken red cells. Similar extracts of 3 other African tumors that are not known to carry the EBV-genome were negative, in spite of the fact that they were derived from EBV-seropositive patients with relatively high anti-EBV (VCA) antibody titers. Crude extraction and DNA-cellulose purification gave equally active extracts, provided that incubation was carried out at 4 degrees C. These results show that the acid fixed nuclear binding technique can be applied to biopsy material. This may be helpful in searching for EBNA carrying cells in heterogeneous normal and tumor tissues in vivo where the direct in situ ACIF staining for EBNA is known to meet great difficulties.

African patients with Burkitt's lymphoma (BL) may show antibodies to the R (restricted) component of the Epstein-Barr (EB) virus-induced early antigens that appear to match in titer the antibodies to EB viral capsid antigen (VCA) as determined with the aid of acetone-fixed smears of EB3 cells. Virus-producing EB3 cells, however, contain the R component as well as VCA so that the correct anti-VCA titers in such cases remain in doubt. Since the R component, but not VCA, was found to be denatured by methanol fixation, the parallel use of acetone- and methanol-fixed EB3 cell smears permitted the determination of the correct anti-VCA titer. Our results showed that the anti-R titers of BL patients can in fact be up to eightfold higher than the anti-VCA titers. Anti-R titers equaling or exceeding anti-VCA titers have been encountered thus far only in BL.

We have studied nine Hodgkin's lymphoma (HD) and ten non-Hodgkin's lymphoma (NHL) patients with extraordinarily high anti-viral capsid antigen (VCA) titers (greater than 5120). Controls were 13 HD and 23 NHL patients with anti-VCA titers between 40 and 2560. High anti-VCA titers were present in NHL patients at the time of diagnosis or within 16 months, whereas the rise of anti-VCA titers in HD patients appeared to be a late event during the clinical course of the disease (mean time from diagnosis, 68 months). In particular, we have asked whether the exceptionally high anti-Epstein-Barr virus (EBV) titers in some HD and NHL patients can be correlated to some of the EBV-specific and -nonspecific parameters of cell-mediated immunity. The battery of non-EBV-specific immunological tests included the assessment of natural killer cell activity and the analysis of T-lymphocyte subclasses according to surface markers, together with spontaneous and mitogen-induced DNA synthesis and their helper or suppressor activity on PWM-generated immunoglobulin synthesis. Outgrowth inhibition (Ol) and leukocyte migration inhibition were used to assess EBV-specific cell-mediated immunity. The majority of the high-titer HD and NHL patients showed a drastically reduced OKT4:OKT8 ratio in their peripheral lymphocyte population. Low-titer HD and NHL patients showed no such reduction. There was no strict correlation between the number of OKT8-positive cells and suppressor activity in the functional PWM-induced immunoglobulin production test. Part of the high-titer HD patients showed defective cellular responses in the outgrowth inhibition test, directed against the proliferation of EBV-transformed (EBV-determined nuclear antigen-positive) cells. Some of them showed also a deficient leukocyte migration inhibition response to EBV-determined nuclear antigen but, interestingly, not to early antigen-VCA. In the NHL group, only one of the high-titer patients showed a similar defect. None of the low-titer HD and NHL patients showed such defects.

Sera from 296 unselected and untreated patients with non-Hodgkin lymphoma (NHL) classified according to the Rappaport and the Kiel systems were analyzed for antibodies to Epstein-Barr virus (EBV). The aim of the study was to determine whether antibody spectra and titers to EBV-coded antigens correlated to clinical and immunological variables and whether the titers were of any prognostic significance. Increased antibody titers to EB viral capsid antigen (VCA) and slightly raised titers to early antigens (EA) of the diffuse (D) and restricted (R) types were noted frequently. Anti-VCA antibody titers correlated to clinical stage and age of the patients but not to histological subgroups according to the Rappaport or the Kiel classification systems. However, anti-VCA titers greater than or equal to 1:2560 were seen only in diffuse lymphomas according to the Rappaport and in non-follicle cell-derived lymphomas according to the Kiel classifications. Patients with complement-receptor-positive diffuse lymphomas had higher anti-VCA titers than complement-receptor-positive nodular cases. Anti-VCA titers also correlated positively to serum IgG levels (p less than 0.01). Total number of lymphocytes separated from peripheral blood and mitogen induced (ConA, PWM) DNA synthesis were recorded before treatment in 56 of the patients. The patients exhibited a significant lymphocytopenia as well as a significantly reduced lymphocyte response to mitogens (p less than 0.001) compared to healthy controls. Elevated anti-VCA titers and anti-EA titers correlated to a good mitogen-induced lymphocyte response (p less than 0.05). Only anti-D 1:40 at diagnosis predicted a poor prognosis.

Sera from a patient with a chronic Epstein Barr virus (EBV) infection contained unusually high anti-EBV antibody titers (1:2560 to 1:10,240 for EA(D) and 1:5,120 to 1:40,960 for VCA). One of these serum samples was shown by immunoprecipitation to recognize at least 11 EBV-specific proteins from virus producer cells labeled in vivo and 10 EBV-specific proteins from in vitro translations of producer cell mRNA. Six of the in vivo labeled proteins (135,000, 89,000, 50,000 to 55,000 doublet, 46,000, and 34,000 daltons) are "early" by their resistance to phosphonoacetic acid, and five (350,000, 220,000, 160,000, 140,000, and 85,000 daltons) are "late" membrane and capsid proteins. The EBV-specific proteins immunoprecipitated from in vitro translations had molecular masses of 150,000, 140,000, 115,000, 52,000, 50,000, 45,000, 34,000, 29,000, 17,000, and 15,000. Subcellular fractionation studies of cells labeled in vivo revealed that the 135,000-dalton protein and part of the 50,000 to 55,000 dalton protein doublet were found in both the nuclear and the cytoplasmic fractions, and thus are good candidates to be components of the EA(D) diffuse-type immunofluorescence observed with many EA-positive sera.

Epstein-Barr-virus (EBV)-induced infectious mononucleosis usually occurs in young adults between the ages of 15 and 30. When it occurs in older individuals, it frequently presents diagnostic problems. This report describes data from 27 such patients aged 40 to 72, all of whom had definitive evidence of a current EBV primary infection. Protracted fever, jaundice, pleural effusion, anemia, or the Guillain-Barré syndrome were dominant clinical findings among these patients. Fourteen patients were hospitalized and numerous diagnostic procedures were performed, including bone-marrow aspirations (8 patients), abdominal CAT scan procedures (4 patients), and liver (2 patients) or lymph-node biopsies (1 patient). Overall, the laboratory data in these patients were similar to those seen in young adults, with the exception of more marked hepatic dysfunction and more prominent antibody responses to the restricted (R) component of the early antigen complex. Particularly difficult were the diagnostic problems encountered in three patients in this study (3/27) who failed to develop heterophil antibodies.

In 42 patients with African Burkitt's lymphoma, we have studied biochemical and clinical correlations with prognosis. Clinical stage and anti-EA titer were the best predictive factors, but lactic dehydrogenase (LDH) and uric acid (UA) concentrations also correlated with stage and prognosis, whereas lactic acid (LA), which was significantly elevated in Stage D, did not significantly correlated with prognosis or with LDH and UA levels. All of these factors with the possible exception of LA reflect the total body burden of tumor. We conclude that the tumor burden is the single most important prognostic factor in Burkitt's lymphoma, and that this is reflected directly by LDH and UA concentrations, and probably indirectly by anti-EA titer.

Sixty-three serum specimens from American patients with nasopharyngeal carcinoma were examined for antibodies to antigens associated with Epstein-Barr virus (EBV) and compared with 98 specimens from patients with other head and neck cancers, 133 from patients with benign head and neck diseases, and 96 from healthy donors. The level of antibody titers to EBV-associated antigens was correlated with nasopharyngeal carcinoma. The anti-EBV profile of elevated antibody titers directed against viral capsid antigen and early antigen was seen in undifferentiated and nonkeratinizing tumors but usually not in squamous cell tumors. Titers tended to rise with large increases in total tumor burden caused by distant metastases, often before clinical evidence of metastases. At the time of diagnosis, antibody-dependent cellular cytotoxicity testing was performed on serum samples from 46 of the patients with nasopharyngeal carcinoma. Pretreatment titers were usually low in patients in whom recurrence developed and were high in most of the patients who had a good response to treatment and have remained free of recurrence.

The presence of Epstein-Barr virus (EBV) genomes in nasopharyngeal and other carcinomas or Burkitt's and other B-cell lymphomas can be established by the demonstration of viral nucleic acid sequences in DNA extracts from biopsy specimens, the detection of EBV-associated nuclear antigen (EBNA) in biopsy imprints, and the inhibition of leukocyte migration by tumor extracts. Of these techniques, the detection of EBNA-positive tumor cells can be performed most readily in the laboratory. This report shows that a patient's antibodies to nuclear antigens can gain access to cell nuclei during the preparation of imprints. If the antibodies are directed against EBNA, nuclear immunofluorescence is elicited solely in the tumor cells when only complement (C') and fluorescein-labeled antibodies to C' are applied to the imprints without prior exposure to anti-EBNA-positive sera. If nonspecific antinuclear antibodies (ANA) are involved, the nuclear immunofluorescence seen in the EBNA-specific and control assays is not limited to the tumor cells but extends to any normal cells that may be present in the imprints. Furthermore, nuclear fluorescence is elicited when solely an anti-human IgG conjugate is applied because ANA is measurable by indirect immunofluorescence, whereas detection of EBNA requires augmentation of the antigen-antibody complexes by C', which differentiates further between EBNA-specific and nonspecific staining. Attachment of antibodies to nuclei can be avoided by minimizing the deposit of blood during imprint preparation and by rapid drying of the imprints. Similar results are obtained experimentally when smears of lymphoblasts are made in the presence of anti-EBNA or ANA.

We have studied five cases suggesting a relation between Epstein-Barr virus infection and primary lymphoma of the central nervous system. A 48-year-old man had primary lymphoma of the central nervous system in the absence of systemic lymphoma or immunosuppression. Development of the tumor was associated with serologic evidence suggesting a recent primary infection with Epstein-Barr virus. DNA preparations from tumor tissue, but not from adjacent normal brain tissue, contained Epstein-Barr virus genomes when hybridized with a probe consisting of the BamHI K fragment of Epstein-Barr virus strain FF41. Evaluation of serum samples from four additional patients with central-nervous-system lymphoma revealed patterns of Epstein-Barr virus-specific antibody that were suggestive of an ongoing infection with EBV. Our results suggest induction of the lymphoma by Epstein-Barr virus.

A 9-year-old white boy developed a fatal primary Epstein-Barr virus (EBV) infection while receiving chemotherapy for acute lymphoblastic leukemia in remission. Histopathological findings at the height of the proliferative phase of the illness were compatible with a virally induced hemophagocytic syndrome. The infection spontaneously converted to complete aplasia of the bone marrow and lymph nodes. Serological studies disclosed that the patient had no antibodies to EBV prior to the infection, but during the acute phase he showed a spectrum and titers of antibodies to EBV-specific antigens characteristic of a current primary EBV infection. A lymph node biopsy obtained 5 weeks after onset revealed Epstein-Barr nuclear antigen in approximately 50% of the cells. The boy's condition deteriorated rapidly, with disseminated candidiasis resulting in cardiorespiratory failure and death. Lymph nodes obtained at autopsy no longer contained Epstein-Barr nuclear antigen-positive cells.

The mean number of tumor-infiltrating lymphoid cells with surface IgA was moderately higher in primary nasopharyngeal carcinoma (NPC) than in their neck gland metastases or in other head and neck tumors. Within the group of primary NPC, patients with large numbers of IgA positive infiltrating cells had a significantly lower mean IgA antibody titer to Epstein-Barr viral capsid antigen. It is unlikely therefore that the unique, frequent elevation of this antibody titer in NPC is due to stimulation of infiltrating IgA positive lymphoid cells among the virus-containing epithelial tumor cells.

Clinical, serologic, virologic, and immunologic evaluations for 31 adults with chronic illness and fatigue suggested that 23 had persisting Epstein-Barr virus infection. Among these 23 patients, cellular immune mechanisms were generally normal, but 4 had mild immunoglobulin deficiencies. However, 20 patients had abnormal serologic profiles specific for Epstein-Barr virus shown by significantly elevated titers of antibodies to the viral capsid antigen or early antigen, or by a deficiency of late-appearing antibodies. In 11 of 15 patients tested, circulating immune complexes were found. Circulating interferon was not found in 18 patients tested, but the activity of 2-5 oligoadenylate synthetase, an interferon-induced enzyme, was increased in 5 patients studied. Of 19 patients, 18 had persisting suppressor T-cell activity typically found in patients recovering from acute infectious mononucleosis. We believe that the Epstein-Barr virus may be associated with chronic illness in adults.

Five distinct Epstein-Barr virus (EBV)-determined nuclear antigens (EBNA-1 to EBNA-5) were recently identified. Antibody responses to these antigens could conceivably differ, and thus prove of serodiagnostic value, in EBV-associated disease processes. As a first step, murine or human cell lines transfected with appropriate EBV DNA fragments and stably expressing either EBNA-1 or EBNA-2 were used to determine the frequency and time of emergence of antibodies to these two antigens in the course of acute and chronic infectious mononucleosis (IM) and to assess their titers in so-called chronic active EBV infections. Following IM, antibodies to EBNA-2 arose first and, after reaching peak titers, declined again in time to lower persistent or even nondetectable levels. Antibodies to EBNA-1 emerged several weeks or months after anti-EBNA-2 and gradually attained the titers at which they persisted indefinitely. The ratios between the anti-EBNA-1 and anti-EBNA-2 titers therefore were generally well below 1.0 during the first 6-12 months after IM and turned to well above 1.0 during the second year. In clear cases of chronic IM, the inversion of this ratio was delayed or prevented. In the less well-defined chronic EBV infections, low ratios were observed in only some of the patients. Because many of these illnesses were not ushered in by a proven IM and often showed EBV-specific antibody profiles within the normally expected range, a causal role of the virus in these cases remains doubtful.

Peripheral or tonsil lymphocyte populations of EBV-seropositive donors give rise to EBV-carrying LCLs upon in vitro explantation. Such lines can arise either by a 2-step mechanism, namely release of virus from some of the explanted cells followed by infection of previously uninfected B cells, or by direct outgrowth of virus-harboring B cells (Rickinson et al., 1974; Dalens et al., 1975; Hinuma and Katsuki 1978; Katsuki et al., 1979). We observed that cells responsible for both the 2-step mechanism and for direct outgrowth are found in the purified B-cell compartment. Virus release was more frequent than direct outgrowth. The majority of virus-releasing cells were found in the low-density fraction that contains large, activated B blasts. Cells that were capable of spontaneous outgrowth in the presence of the viral inhibitor PFA and of virus-neutralizing antibody gave rise to cell lines that carried the sex chromosome marker of the original donor, rather than that of admixed cord blood lymphocyte of the opposite sex. Such cells were found in both the low- and the high-density fractions. The majority of the EBV-carrying B cells in vivo are thus low-density blasts. Rare small B cells of high density harboring EBV were capable of spontaneous outgrowth. This may be indicative of a host control mechanism that is removed upon cultivation in vitro.

Antineutrophil antibodies were detected in the serum of 12 of 14 patients with acute Epstein-Barr virus-induced infectious mononucleosis. These antibodies were present in two patients with mononucleosis and severe neutropenia, and in 10 patients with mononucleosis uncomplicated by severe neutropenia. Antineutrophil antibodies were not detected in serum from five patients with cytomegalovirus-induced mononucleosis, or five renal allograft recipients with primary or reactivation Epstein-Barr virus infection. This study suggests that antineutrophil antibodies are among those produced by the polyclonal activation induced by Epstein-Barr virus during acute infectious mononucleosis.

The prevalence and titers of antibodies to capsid antigens of Epstein-Barr virus ad to the diffuse and restricted components of the Epstein-Barr virus-induced early antigen complex were determined in 109 families of a semirural community in Louisiana. Titers of antibody to the capsid antigens larger than or equal to 10 were found in 84 percent of children aged two to five years, and the prevalence increased with age to nearly 100 percent. There was a positive but variable correlation of the prevalence of anti-capsid antigen reactivity with low socioeconomic status and crowding. An overrepresentation of high titers of antibody to capsid antigens was present in individuals with a past history of pneumonia and urinary tract infections. The geometric mean titers of antibody to capsid antigens were highest in early childhood, lowest in adolescence and young adulthood, and high in the elderly. Females in all age groups and tonsillectomized children showed a higher geometric mean titer than their male and nontonsillectomized counterparts, respectively. Antibodies to the early antigen complex were found rarely (8.2 percent) and only in sera with relatively high titers of antibody to capsid antigens.

We studied the interrelation among herpes-virus infections, T-lymphocyte subsets, opportunistic infections, and renal histopathology in 28 recipients of renal allografts. All primary or reactivated herpesvirus infections occurring in the first three months after transplantation in recipients of cadaveric grafts accompanied persistent inversions in the ratio of OKT4 (helper/inducer) to OKT8 (cytotoxic/suppressor) lymphocytes. In the less heavily immunosuppressed recipients of organs of living related donors, these inversions were seen only in association with clinically apparent cytomegalovirus infections. Five of seven opportunistic infections occurred in patients with OKT4/OKT8 ratios of less than 1.0. Biopsy specimens from patients with renal dysfunction occurring in association with a low OKT4/OKT8 ratio frequently revealed glomerular damage rather than acute cellular rejection. Monitoring of T-lymphocyte subsets provides early evidence of herpesvirus infections and identifies patients at increased risk for opportunistic infection after renal transplantation.

Fifty-six patients with a clinical and laboratory diagnosis of infectious mononucleosis who had not been ill for more than seven days, were randomised for peroral treatment with acyclovir (800 mg five times daily) or placebo for seven days in a double blind trial. Clinical, virological and immunological parameters were monitored in each patient for six months. During treatment, shedding of Epstein-Barr virus' as assessed in 36 patients, was significantly reduced (p less than 0.001). However, virus production in the oropharynx returned to pre-treatment levels one week after the cessation of therapy. Virus was detected in 35 patients at enrollment and in 28 of 36 patients at the six-month control. No effect on the clinical course of the disease was noticed. The virus-specific antibody response was also unaffected. A significant reduction in spontaneous outgrowth of in vivo Epstein-Barr virus-infected B-lymphocytes was found at 180 days after treatment in four acyclovir-treated patients compared to six controls (p less than 0.001). In another three patients with over-whelming clinical symptoms causing airway obstruction and/or disseminated intravascular coagulopathy, treatment with intravenous acyclovir (10 mg/kg three times daily) was combined with prednisolone (0.7 mg/kg daily) for ten days. Virus shedding ceased transiently during treatment, but returned to initial levels within one week. A dramatic clinical effect on the pharyngeal oedema and general health of the two patients with airway obstruction was noticed, but was much less evident in a patient with intravascular coagulopathy.

Three different assays for detection of antibodies to the human immunodeficiency virus (HIV) were conducted on 677 sera obtained from 1964 to 1975 from male and female children and adults in Uganda and other countries in Africa. Several sera were collected from individuals with Kaposi sarcoma. No evidence of antibodies to the virus was noted up to 1975. These results strongly suggest that the emergence of HIV in Africa occurred relatively recently. Further studies are required to determine the geographic origin of the acquired immunodeficiency syndrome virus.

Sera from patients with Kaposi's sarcoma (KS) were examined for antibody titres to cytomegalovirus (CMV), Epstein-Barr virus (EBV) and herpes simplex virus (HSV) types 1 and 2 by four techniques: indirect haemagglutination (IHA), complement fixation (CF), virus neutralization (NT) and indirect immunofluorescence (IF). The patients were classified, according to the stage of disease, as progressive and regressive. Control sera were obtained from healthy adults, matched for age, sex, race, socioeconomic status and geographic location, as well as from patients with melanoma, some of whom were receiving chemotherapy similar to that given to the KS patients. All KS sera contained CMV-neutralizing antibodies. Seventy-five percent of the European KS patients, mainly regressors, showed elevated anti-CMV titres by IHA with a significant increase in the geometric mean over the corresponding healthy adult group and the melanoma group. An overrepresentation of high anti-CMV titres, although less marked, was found by CF. There was no significant association with antibodies to EBV, HSV-1 and HSV-2 related antigens. By contrast, the African KS patients, mainly progressors, did not show a serologic association with CMV or with EBV and HSV-1 and 2. The implication of these results is discussed.

gamma-Glutamyl transpeptidase (GGTP) is a sensitive but nonspecific index hepatobiliary disease. In infectious mononucleosis (IM) or the mononucleosis-like disease attributable to cytomegalovirus (cytomegalovirus-induced IM), GGTP reverted to normal later than aspartate aminotransferase and alkaline phosphatase. In three cases elevated serum GGTP activity persisted for up to 24 months -- raising the question of persistent 'post-IM' hepatitis. Such prolonged GGTP activity was unusual in other late IM specimens. Possible, but unlikely, causes for such persistent GGTP activity are an unusual degree of hepatic damage during acute IM, excessive induction of microsomal enzyme system activity by drugs, or unusual Epstein-Barr virus carrier state activation that might contribute to ongoing hepatic structural damage. Other markers of chronic hepatocellular disease including aspartate aminotrasferase, alkaline phosphatase, and bilirubin were normal in late specimens from these 3 patients. The cause of their persistent elevated GGTP activities remains unknown.

Serial sera from 50 marrow transplant recipients were examined for their spectra and titers of antibodies to EBV-specific antigens. Immediately before or after transplant, blood products passively transferred antibodies to EB viral capsid antigen (VCA) and EBV nuclear antigen (EBNA). In most recipients, passively-transferred antibodies were replaced by endogenous antibodies regardless of whether donor or recipient had EBV antibodies before transplantation. Commencement or resumption of endogenous EBV antibody production was not associated with signs of infectious mononucleosis or heterophil antibody responses. Antibodies to VCA rose to abnormally high titers, followed successively by antibody to early antigens (EA), and disproportionately low levels of anti-EBNA. Unusually high anti-VCA and anti-EA levels persisted when tests of immune function returned to normal. Antibodies to other herpes group viruses showed no consistent changes. We conclude that (1) EBV does not cause significant clinical problems in marrow transplant recipients; (2) persistent EBV infection can become established or reestablished in the presence of antibodies to EBV; (3) marrow transplant recipients show the same exaggerated immune response to EBV as other immunodeficient patients; and (4) the pattern of EBV-specific antibodies may be a more sensitive measure of defective cell-mediated immunity than most conventional tests of immune function.

An undifferentiated lymphocytic lymphoma of mesenteric lymph nodes occurred in a young boy with ataxia-telangiectasia. Two independent tests, Epstein-Barr virus (EBV)-cRNA/DNA hybridisation and EBV DNA/DNA reassociation kinetic analysis, showed 53 and 68 EBV genome equivalents per cell respectively, which was compatible with an EBV-genome-carrying tumour. Whether this was a polyclonal lymphoproliferation or a monoclonal tumour could not be determined owing to lack of suitable material. The presence of EBV genomes should be sought in lymphomas arising in ataxia-telangiectasia and other immunodeficiencies.

Studies were made of the expression of the Epstein-Barr virus (EBV) in somatic hybrids of Burkitt tumor cells and human or mouse cells to determine whether EBV genetic information associated with the capacity to transform leukocytes of human and non-human primates could be maintained and expressed in nonlymphoblastoid cells. Data obtained thus far suggest that at least one characteristic associated with cellular transformation (loss of contact inhibition) is expressed only in nonlymphoblastoid cells in which the EBV genome is maintained. In addition, we have demonstrated that human epithelial/Burkitt hybrid cells (D98/HR-1 and D98/Raji) are more oncogenic in nude (athymic) mice than are cells of the human epithelial parental line, D98, or one of the Burkitt lymphoblastoid parent cell lines (Raji); the HR-1 Burkitt parent cell line was as oncogenic as the hybrid cell lines but the time required to induce tumors was much longer. Thus, human epithelial cells show alteration of growth properties in vitro and in vivo after cellular hybridization with Burkitt tumor cells.

Since B-lymphocytes are targets and a continuing habitat of Epstein-Barr virus (EBV) and the cell-mediated immune system becomes secondarily involved, one may anticipate that primary and persistent EBV infections in immunologically compromised individuals take unusual courses. Depending on the immunological defect, the clinical, hematological, and serological responses to primary EBV infections may be more or less pronounced than in immunologically competent patients. Infectious mononucleosis has per se an immunosuppressive effect which may enhance a preexisting immune defect. The persistent latent viral carrier state which regularly ensues after the primary EBV infection may become decontrolled by immunosuppressive diseases or therapy, leading rarely to illnesses referable to the virus but often to increases in the titers of antibodies to viral capsid and early antigens and/or declines in the antibody titer to EBV-associated nuclear antigen. Absence or dysfunction of different leukocyte subpopulations may account for the differential changes in antibody patterns.

Using the indirect leukocyte migration inhibition technique T cells have been identified as being responsible for Epstein-Barr virus nuclear antigen-induced specific leukocyte migration inhibitory factor production. The response was dependent on the presence of macrophages or their product, T-lymphocyte activating factor.

Ten consecutive diffuse histiocytic lymphoma (DHL) cell lines established in our laboratory were studied for the presence of Epstein-Barr virus (EBV) genomes, lysozyme, nonspecific esterase and other cytochemical reactions, phagocytic activity, cytoplasmic immunoglobulin light and heavy chains, and surface receptors to sheep erythrocytes, complement, and the Fc fragment of immunoglobulin. In agreement with previous studies performed on biopsy specimens, our results indicate that the diffuse histiocytic lymphomas, as a histopathologic entity, represent a heterogeneous group of neoplasms, the majority of which are B-lymphocyte in origin. The cell lines appear to fall into three categories based on the following criteria: 1) presence of monoclonal cytoplasmic immunoglobulins (B-lymphocytic type, 6/10 cell lines); 2) presence of non-specific esterase, phagocytic activity, and/or lysozyme (histiocytic type, 2/10 cell lines); and 3) absence of all lymphoid and histiocytic cell characteristics (null cell type, 2/10 cell lines). Despite the fact that many of the lymphoma patients had positive serologies to EBV antigens, all of the DHL cell lines were negative for the presence of EBV genomes. Both of the two B-lymphocytic type and one of the two histiocytic type lines tested were susceptible to infection with EBV, as indicated by synthesis of early antigen and also, in a small proportion of the infected cells, of viral capsid antigen. These prototypic DHL cell lines may permit the development of new criteria for the differential diagnosis and treatment of this highly malignant and diverse group of lymphomas.

Twenty-seven adults with a diagnosis of the chronic fatigue syndrome were enrolled in a double-blind, placebo-controlled study of acyclovir therapy. The patients had had debilitating fatigue for an average of 6.8 years, accompanied by persisting antibodies to Epstein-Barr virus early antigens (titers greater than or equal to 1:40) or undetectable levels of antibodies to Epstein-Barr virus nuclear antigens (titers less than 1:2) or both. Each course of treatment consisted of intravenous placebo or acyclovir (500 mg per square meter of body-surface area) administered every eight hours for seven days. The same drug was then given orally for 30 days (acyclovir, 800 mg four times daily). There were six-week observation periods before, between, and after the treatments. Three patients had acyclovir-induced nephrotoxicity and were withdrawn from the study. Of the 24 patients who completed the trial, similar numbers improved with acyclovir therapy and with placebo (11 and 10, respectively). Neither acyclovir treatment nor clinical improvement correlated with alterations in laboratory findings, including titers of antibody to Epstein-Barr virus or levels of circulating immune complexes or of leukocyte 2',5'-oligoadenylate synthetase. Subjective improvement correlated with various measures of mood. We conclude that acyclovir, as used in this study, does not ameliorate the chronic fatigue syndrome. We believe that the clinical improvement observed in most patients reflected either spontaneous remission of the syndrome or a placebo effect.

The sera of 12 patients with presumed chronic active Epstein-Barr virus (EBV) infection lacked antibody to a component of the Epstein-Barr nuclear antigen (EBNA) complex encoded by the BamHI K fragment of viral DNA. This anomaly, detected in approximately 18% of sera obtained from patients with a diagnosis of "chronic mononucleosis," was more often found in patients with severe disease (approximately 32%) who had objective clinical findings and markedly elevated antibody titers to EBV replicative antigens than in those patients with the "fatigue syndrome" (10%). The lack of antibody to the K nuclear antigen is specific because most of those who did not have antibody to the K antigen made antibody to other latent nuclear (EBNA 2) antigens or nuclear early antigens. Such patients are thus able to lyse immortalized cells, release nuclear products, and present them to the immune system. Three hypotheses are suggested to explain the lack of antibody to the K antigen: a viral mutation, a failure of immune recognition, or lack of in vivo expression of the antigen due to extensive viral replication. Lack of antibody to one component of EBNA may serve as an objective serological marker for certain patients with chronic EBV infection.

Soluble membrane fractions derived from Raji cells trigger lymphocytes of Epstein-Barr virus (EBV)-seropositive, but not EBV-seronegative, individuals to release a lymphokine that inhibits leukocyte migration. The reaction can be blocked by the sera of patients with EBV-DNA-carrying tumors, Burkitt lymphoma, or nasopharyngeal carcinoma. Absorption of these sera with EBV-positive, but not EBV-negative, cells abrogates their blocking activity. These findings suggest that the antigen responsible for the leukocyte migration inhibition reaction is an EBV-encoded or an EBV-induced membrane component. The antigen is not identical with EBV-associated nuclear antigen or any other known antibody-detected EBV antigen.

Biopsy specimens from Alaskan Native patients with nasopharyngeal carcinoma (NPC) and from other patients seen on the otolaryngology service were tested for Epstein-Barr virus-specific DNA and nuclear antigen (EBNA). Serum samples from both groups were tested for various EBV-related antibodies. EBV DNA and EBNA results were in agreement in 29 of 31 tissue specimens tested by the two methods. Ten of 11 biopsies containing NPC cells were positive for EBV DNA. Two NPC patients had biopsies that showed only atypical epithelium but were also positive for EBV DNA or EBNA. The other tissue specimens were negative except for biopsies from two patients: one with a parotid gland lymphoepithelial lesion; another with undifferentiated carcinoma of salivary gland origin.

A young girl with familial nephronophthisis and chronic renal failure contracted a primary Epstein-Barr virus infection after renal transplantation. During the illness she developed a clinical picture of fever and pneumonitis which closely resembled the posttransplantation syndrome usually associated with cytomegalovirus, although she had no evidence of cytomegalovirus infection. A younger sibling with the same renal disease was found retrospectively to have apparently had an earlier subclinical Epstein-Barr virus infection.