A case control study on immunity to two Epstein-Barr virus-associated antigens, and to herpes simplex virus and adenovirus in a population-based group of patients with Hodgkin's disease in Denmark, 1971-73

Infectious mononucleosis and Hodgkin's disease--a similar seasonality

The presentation of Hodgkin's disease and acute infectious mononucleosis (glandular fever) due to Epstein-Barr virus, have similar seasonal features with the peak incidence around March. The extent of seasonal variation is also similar. Seasonality of Hodgkin's disease is most obvious and also significant in adult age groups below the age of 40. Amongst those over 40 years, seasonality was no longer present in the 40-59 but returned over age 60. Seasonal similarity does not prove a relationship. However two speculations are made on possible mechanisms. Firstly glandular fever may accelerate presentation in young adults, destined to present with HD. Secondly the Epstein-Barr virus may have an inherent seasonal behaviour whether causing acute infectious mononucleosis or when latent and playing a role in the aetiology of Hodgkin's disease.

Epstein-Barr virus as an agent of haematological disease

Epstein-Barr virus (EBV) encodes genes that permit its persistence in human B lymphocytes and genes that ensure its replication in epithelial cells. Immune restraints on the virus are usually so effective that most EBV infections are limited to a minute fraction of B lymphocytes and of epithelial cells. As a result, most EBV infections are never symptomatic. Occasionally, the virus causes disease, often with the cooperation of the immune system or other less characterized cofactors. Infectious mononucleosis, a generally self-limited lymphoproliferative illness common in adolescents and young adults, is due to primary EBV infection and to the brisk cellular immune response it elicits. Lymphoproliferative disorders of EBV-infected B cells arise almost exclusively when cellular immunity is grossly compromised. EBV-positive Burkitt's lymphoma contain a translocated and deregulated c-myc oncogene and EBV-positive non-Hodgkin's lymphomas are characterized by the presence of Reed-Sternberg's and Hodgkin's cells, features that have not been directly linked to EBV. Many recent observations, however, including evidence that virus infection precedes malignant transformation and is often associated with a characteristic pattern of viral gene expression, provide continued interest in the relationship between the virus and these haematological malignancies.

Evaluation of Epstein-Barr virus antibody patterns and detection of viral markers in the biopsies of patients with Hodgkin's disease

We assessed the relationship of Epstein-Barr virus (EBV) serology to the presence or absence of EBV genome in 39 cases of Hodgkin's disease (HD). Biopsies from patients included in 2 previous published studies, 1 involving patients from the United States (eastern Massachusetts) and 1 from Denmark, were evaluated for EBV (EBER-1) and latent membrane protein (LMP-1). The presence of EBV in Reed-Sternberg cells in the biopsies correlated with the histologic subtype of HD (mixed cellularity and lymphocyte depletion) but not with IgG antibody titers against the viral capsid antigen (VCA). These data suggest that, unlike Burkitt's lymphoma, the IgG antibody against VCA is not predictive of the presence or absence of EBV in Reed-Sternberg cells in HD. The predictive value of other antibodies should be evaluated.

Primary cerebral lymphoma: a study of 47 cases probed for Epstein-Barr virus genome

AIMS

To determine the prevalence of Epstein-Barr virus genome in primary cerebral lymphomas occurring in the absence of immune suppression.

METHODS

Forty eight consecutive patients with lymphomas restricted to the central nervous system were identified, all of whom had had neurosurgical biopsies performed at the National Hospitals for Neurology and Neurosurgery, London. Only five patients had some form of underlying immune deficiency; 43 were apparently normal. The tumours were studied with immunohistochemical markers and by in situ hybridisation, using a biotinylated probe to the internal repeat region of Epstein-Barr virus.

RESULTS

All the lymphomas were B cell in origin. Tumours from the five immunosuppressed patients all showed hybridisation, as did two of the "spontaneous" tumours.

CONCLUSIONS

This is the largest series of cerebral lymphomas so far probed for Epstein-Barr virus genome: as more are examined, it is suggested that a small proportion of the tumours from immunocompetent patients will also contain the virus.

Antibodies to human herpes virus-6 and clinical course in patients with Hodgkin's disease

Serial serum samples from 37 patients with Hodgkin's disease (HD) and 39 healthy controls were studied for antibodies to human herpes virus-6 (HHV-6) using ELISA and indirect immunofluorescent antibody (IFA) tests and to the Epstein-Barr virus (EBV) using a radio-complement fixation assay. Antibodies to HHV-6 in the pre-treatment sera from the HD patients were not significantly different from those of controls, but significant changes in titers related to clinical course were noted among the HD patients. HHV-6 IFA titers increased significantly in the course of follow-up in patients who relapsed and decreased significantly over time in patients who did not. These serologic studies support tissue-based investigations indicating that EBV plays a greater etiologic role in HD than HHV-6, although HHV-6 serology may be of prognostic value or may assist in identifying individuals with immunologic abnormalities. The identification of diverse HHV-6 antibody patterns using different assays may reflect the presence of a number of antibodies with varying implications, similar to those identified for EBV.

Hodgkin's disease

The epidemiological features of Hodgkin's disease (HD) suggest that it is a heterogeneous condition which may have different aetiologies in different age groups. The risk factors for the development of HD in young adults suggest that delayed exposure to a common infectious agent may be involved in this age group. Seroepidemiological studies have shown that HD patients have elevated antibody titres to Epstein-Barr virus (EBV) and the elevated titres have been shown to precede the diagnosis of HD. Recent molecular studies provide support for the idea that EBV is involved in the pathogenesis of HD. EBV genomes are consistently found in a proportion of tumour biopsies, the EBV-infected cells are clonal and the EBV genomes have been localized to Reed-Sternberg cells. Furthermore, EBV latent gene products are expressed by the Reed-Sternberg cells. The majority of HD samples from patients aged greater than 50 years and less than 15 years are EBV positive, whereas the minority (less than 15%) of samples from young adults contain detectable EBV DNA. The results suggest that EBV plays a role in HD in children and older adults but that other agents, possibly other viruses, are involved in young adults.

Viruses in human cancers

Viruses may contribute to the development of human tumors by different mechanisms: indirectly by inducing immunosuppression or by modifying the host cell genome without persistence of viral DNA; directly by inducing oncoproteins or by altering the expression of host cell proteins at the site of viral DNA integration. Human cancers associated with papillomavirus, hepatitis B virus, Epstein-Barr virus, and human T cell leukemia-lymphoma virus infections are responsible for approximately 15 percent of the worldwide cancer incidence. Cancer of the cervix and hepatocellular carcinoma account for about 80 percent of virus-linked cancers. Because experimental and epidemiologic data imply a causative role for viruses, particularly in cervical and liver cancer, viruses must be thought of as the second most important risk factor for cancer development in humans, exceeded only by tobacco consumption.

Detection of Epstein-Barr virus genomes in Hodgkin's disease: relation to age

An investigation as to whether any particular subgroup of patients with Hodgkin's disease was particularly likely to be Epstein-Barr virus (EBV) genome positive was made on samples from 95 patients. These were grouped according to age and Hodgkin's disease subtype, and analysed using Southern blot analysis. Most samples from children or adults aged 50 years or over contained detectable EBV genomes; samples from young adults were only rarely positive. The differences in EBV positivity by age were highly significant, but there was no significant association between EBV and histological subtype after allowing for the effect of age. The results support the hypothesis that Hodgkin's disease in different age groups may have different aetiologies, and suggest that EBV does have a pathogenetic role in Hodgkin's disease in children and older age groups.

Immunologic observations in close relatives of two sisters with mammary Burkitt's lymphoma. Mammary Burkitt's lymphoma in sisters

In a sibship of four sisters, two had Burkitt's lymphoma localized to the breast. Their pretreatment Epstein-Barr virus (EBV) serology were not examined. No EBV genome was demonstrated in the tumors using an in situ hybridization technique. The mother showed an abnormal antibody response to EBV infection consisting of elevated IgA and IgG antibody titers to viral capsid antigen (VCA) and high IgG antibody titer to early antigen. Furthermore, one of the two healthy sisters showed elevated IgG antibody titer to VCA. The EBV serology is mimicking the findings in female carriers of the X-linked lymphoproliferative syndrome.

Viral involvement in Hodgkin's disease: detection of clonal type A Epstein-Barr virus genomes in tumour samples

Thirty-five cases of Hodgkin's disease (HD) were analysed for the presence of Epstein-Barr virus (EBV) and human herpesvirus-6 (HHV-6) DNA. EBV genomes were detected in 11/35 cases while none of the cases was positive for HHV-6. Ten of the EBV-positive cases were subsequently analysed using a probe for the terminal region of the virus; the results suggested that the EBV-infected cells were clonally expanded. EBV subtypes specific DNA amplification was used to demonstrate that EBV subtype A, and not subtype B was present in the EBV-positive cases. The age distribution of the EBV-positive cases indicated a statistically significant trend for an increase in positivity with increasing age. This is the first indication that EBV is significantly associated with any subset of HD patients.

The seroepidemiology of human herpesvirus-6 (HHV-6) from a case-control study of leukaemia and lymphoma

Sera from an epidemiological case-control study of leukaemias and lymphomas conducted between 1980 and 1986 were examined for reactivity to human herpesvirus-6 (HHV-6) by an indirect immunofluorescence assay. Statistical analyses of the data revealed higher HHV-6 seroprevalence and antibody titres in the cases, particularly evident in the disease subtypes acute myeloid leukaemia, Hodgkin's disease (HD), and low-grade non-Hodgkin's lymphoma. Within the control group alone, HHV-6 seroprevalence was placed at 55% at a serum dilution of 1:40. The controls also displayed higher seropositivity in females as compared with males. Further analyses suggest an association of increased HHV-6 seropositivity and geometric mean titre ratio with HD among young adults lacking social contact in the family group. This finding might indicate late exposure to HHV-6 in such persons and could possibly signify late exposure to a number of viruses, including those hypothesized as playing a role in the aetiology of HD. Previous reports have nominated Epstein-Barr virus as a possible candidate. Our results suggest that HHV-6 should be included in further investigations of the aetiology of HD.

Hodgkin's disease and Epstein-Barr virus. Altered antibody pattern before diagnosis

In patients with Hodgkin's disease, titers of IgG antibody against viral capsid antigen of Epstein-Barr virus and the prevalence of antibodies against early antigen are higher than expected. To evaluate whether this condition antedates diagnosis, we identified 43 persons with Hodgkin's disease, from whom blood had been drawn and stored for an average of 50.5 months before diagnosis, and 96 controls from the same populations, from whom blood had been drawn at the same time. The relative risks of Hodgkin's disease associated with elevated levels of IgG and IgA antibodies against capsid antigen were 2.6 (90 percent confidence interval, 1.1 to 6.1) and 3.7 (1.4 to 9.3), respectively. For Epstein-Barr nuclear antigen, the relative risk was 4.0 (1.4 to 11.4), and for early antigen D it was 2.6 (1.1 to 6.1). However, the prevalence of IgM antibody against capsid antigen was substantially lower in patients with Hodgkin's disease (0.22 [0.04 to 1.3]). These associations were stronger in serum samples obtained at least three years before diagnosis than in serum samples obtained closer to diagnosis. We conclude that the development of Hodgkin's disease may in some patients be preceded by enhanced activation of Epstein-Barr virus. Whether Epstein-Barr virus has a direct role in the pathogenesis of the disease or is simply a marker for a more fundamental factor affecting the immune control of latent infections is unknown.

Primary central nervous system lymphoma related to Epstein-Barr virus in a patient with acquired immune deficiency syndrome

The study of a patient suggested a relationship between Epstein-Barr virus infection and primary lymphoma of the central nervous system in the acquired immune deficiency syndrome. Deoxyribonucleic acid preparations from tumor tissue contained 30 to 100 copies of Epstein-Barr virus genome per cell when hybridized with a probe consisting of the Bam-HI K fragment of Epstein-Barr virus strain FF41. This hybridization study suggests that induction of this patient's central nervous system lymphoma was related to Epstein-Barr virus infection.

Diagnosis of Hodgkin's disease hampered by an Epstein-Barr virus infection treated with acyclovir

We report a case of Hodgkin's disease associated with Epstein-Barr virus (EBV) infection in a 75-year-old male. The patient was given a 5-day course of acyclovir to which he responded well, with partial resolution of the lymphoma and return to well-being. A biopsy from the lymphoma after acyclovir treatment showed a change in the histological picture with a reduction in the number of giant cells. Relationships between EBV infection and Hodgkin's lymphoma are discussed.

A population-based case-control study of EBV and other viral antibodies among persons with Hodgkin's disease and their siblings

The Epstein-Barr virus (EBV) has been consistently found to be associated with Hodgkin's disease (HD) in two ways: cases generally have elevated titer distributions of antibodies against the viral capsid antigen, and the occurrence of HD among persons with a history of EBV infectious mononucleosis is two or three times higher than expected. We evaluated this association by measuring the prevalence and level of antibodies against EBV and related viruses among 304 cases of HD interviewed in a population-based study in comparison to 285 of their siblings. The most significant finding was that antibody titers to the viral capsid antigen of EBV were elevated (greater than or equal to 1:320) in 39% of the cases and in only 14% of the sibling-controls; the relative risk adjusted for age and sex was 4.1. The geometric mean titer was three-fold higher among cases (175.6 vs. 58.1) Subjects who reported a history of IM had a higher distribution of titers than those who did not. Cases also had elevated titers against the early antigen of EBV - the D Component being most prominent. A significantly higher proportion of cases has elevated titers against CMV, relative risk = 3.4, but the prevalence of CMV antibody was relatively low and not consistently higher among cases. The findings support the hypothesis that EBV may play a role in the pathogenesis of HD among persons with elevated titers. The findings neither confirm nor deny a possible role of CMV.

Central-nervous-system lymphoma related to Epstein-Barr virus

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.

HLA and susceptibility to Hodgkin's disease

Strong arguments supporting a genetic linkage between susceptibility to HD and HLA are reported. These observations are based on data from 33 multiplex case families, gathered from international series and from our own studies. They confirm the disturbed segregation of HLA haplotypes among pairs of affected siblings (P less than 0.0005). An excess of a shared haplotype among first cousin pairs of patients is also observed (P less than 0.05). When both sib pairs and cousins are taken together, the segregation distortion is even greater (P less than 0.0002). Although the excess of HLA-identical affected sib pairs would favor a recessive mode of transmission of the disease, the lod score analyses do not allow one to conclude a simple genetic pattern. A two-gene model, based on epistatic cooperation, is discussed and could fit with an intermediate mode of transmission. The review of population data confirms the generally admitted trend of higher susceptibility borne by HLA-A1. There are converging arguments in favor of the prevalence of A1, B5, B18 in HD, and in particular A1 in the mixed cellularity form, while the haplotype, A1, B8, predominant in long survivors seems to possess a protective effect. It is expected that more data from multiplex families and prospective series of unrelated patients, fully HLA typed, may help to bring about a better understanding of the first reported HLA linkage with malignancy.

Epstein-Barr virus, fatal infectious mononucleosis, and Hodgkin's disease in siblings

Epstein-Barr virus (EBV) infection in a family resulted in a fatal disseminated heterophil negative infectious mononucleosis syndrome in a nine-year-old girl. This was followed closely by a similar disease process in her six-year-old brother which evolved over a one-year period into Stage IIIB Hodgkin's disease. Finally, three years after the index EBV case in the daughter, the mother was diagnosed with a non-Burkitt's-type undifferentiated lymphoma that proved rapidly fatal. The EBV involvement in the sister and brother was well documented serologically and virologically. The pathologic diagnosis was established and confirmed by more than one pathologist. There was no obvious evidence for either a specific or general immune defect in any of the family members tested. The progression of the six-year-old boy's EBV infection from a benign, yet disseminated disease process into a histopathologically confirmed case of Hodgkin's disease offers a strong suggestion that this virus was not behaving solely as a passenger. Especially relevant is the fact that the boy never fully recovered from his EBV infection and essentially became persistently infected with the virus as evidenced by his EBV-EA serology and virology results.

Lymphomatoid granulomatosis and Epstein-Barr virus

A case report of a patient with lymphomatoid granulomatosis presenting initially as a reactivated Epstein-Barr virus infection is presented. Epstein-Barr virus is proposed in the possible role of establishing of an immunologically compromised state that may have set the stage for dissemination of this disease process. Of interest is the fact that successful chemotherapeutic management of the disease was accomplished using prednisone and cyclophosphamide. Furthermore, this clinical success was reflected in a decreasing Epstein-Barr virus early antigen-antibody titers accompanied by increasing antivirus capsid antigen titers; hence, it appears that laboratory markers of the response of lymphomatoid granulomatosis to treatment are available in the form of soluble immune complexes, antibodies to Epstein-Barr virus-coded antigens early antigens, Epstein-Barr nuclear antigens and/or virus capsid antigens as well as the active E rosette assay for T-cells. Finally, these data, although supporting the role of Epstein-Barr virus in the pathogenesis of lymphomatoid granulomatosis, suggest the need for further study in additional patients to verify the results.

Epstein-Barr virus infection and neoplasia

Once acquired, Epstein-Barr virus (EBV), a latent virus, remains in the body for what appears to be the lifetime of the human host. Circumstantial data suggest EBV is involved in clinical disease including malignancies far more often than previously recognized. A serologic test for early antigen (EA) is more specific for diagnosing active EBV disease than the monospot or heterophile test. A case study of active Epstein-Barr infection is reported showing persistently elevated early antigen titers prior to and following malignant transformation.

In vitro susceptibilities of normal human skin fibroblasts to oncoviruses, and the decreased susceptibility to HSV of fibroblasts from untreated Hodgkin's patients

Fibroblast cultures established from the skin of 56 healthy controls and 15 untreated Stages I and II Hodgkin's patients (HD) were studied in their 3rd, 4th and 5th in vitro passage with respect to transformation with Simian sarcoma virus (SSV) and SV40 and with respect to replication of herpes simplex virus (HSV) Types 1 and 2, pox virus and interferon release. Susceptibility to the 5 viruses varied independently, except for an inverse correlation between susceptibility to SSV and HSV. HD cultures showed a depressed replication of both types of HSV. There was a borderline (P = 0.02) correlation between magnitude of HSV replication and presence of HL-A type B-w44, but this does not explain the HD control difference. Furthermore, the level of serum antibodies to HSV common antigen was not related to magnitude of in vitro replication. The results thus speak against generally enhanced cellular susceptibility to HSV as a reason for the high titres of serum antibodies to HSV in HD patients.

Presence of elevated antibody titres to Epstein-Barr virus before Hodgkin's disease

Sera taken 12 and 21 months before the diagnosis of Hodgkin's disease in two patients showed higher antibody levels to several Epstein-Barr-virus (EBV) antigens than did sera from eight matched controls. In one case the titres of all EB antibodies except that to nuclear antigen were raised in a serum sample obtained 45 months after the diagnosis was made. Antibody levels to herpes simplex, cytomegalovirus, and varicella zoster viruses were normal in both cases. A third patient with histiocytic lymphoma had normal EBV and other herpes antibody titres in a serum sample taken 40 months before diagnosis.

Primary Epstein-Barr virus infection in early childhood

In a prospective study 43 consecutive children in hospital, aged between 6 months and 7 years and displaying at least one of the clinical signs of infectious mononucleosis (IM), were investigated for Epstein-Barr (EB) virus-specific IgM antibodies by an indirect immunofluorescence test. On this basis EB virus infection was considered confirmed in 8 patients, each of whom had IgM antibodies in the initial serum sample. In one additional patient, IgM antibodies were only detected in a second sample. The IgM antibodies disappeared with 3-11 weeks. Assessment of IgG antibodies had no diagnostic value in the acute phase of IM. Clinically the 3 youngest children, about 1 year of age, were diagnosed as having pneumonia or hepatitis, the 5 other consecutive patients as having IM. Hepatosplenomegaly was fairly frequently associated with IM, while sore throat, lymphadenopathy, and rash were often signs of other diseases. Only the oldest child had heterophil antibodies. Atypical lymphocytes (greater than 10%) were present in 4 of the 9 IM cases and were seen in children with other diseases as well. Our data stress the importance of measuring EB virus-specific IgM antibodies in order to diagnose IM in early childhood.

Epstein-Barr virus-related serology in marrow transplant recipients

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.

The relation between Epstein-Barr virus antibodies and clinical symptomatology and immunodeficiency in patients with Hodgkin's disease

Anti-Epstein-Barr virus (EBV) titers were measured in the sera of 37 patients with Hodgkin's disease and in 40 normal controls. The patients were grouped according to histologic type, clinical symptomatology (relapse or remission), and their immune state (immunodeficient or non-immunodeficient). Anti-Epstein-Barr nuclear antigens (EBNA) and antiviral capside antigens (VCA) titers were higher in patients with Hodgkin's disease than in the controls. Anti-EBNA titers were significantly higher in patients with lymphocyte predominance, and anti-VCA titers were significantly higher in patients with mixed cellularity. Patients in clinical relapse had higher anti-EBV antibody titers than patients in remission or those in the control group. Immunodeficent pateints had significantly higher anti-VCA titers than either the non-immuno-deficient or the control cases. We believe high anti-EBV titers are related to immunodeficiencies. The relationship between Hodgkin's disease and EBV is discussed.

The immunopathology of Hodgkin's disease

Answers are beginning to emerge to the questions posed in the introduction to the preceding section. In vitro techniques that allow characterization of malignant cells have particular relevance when, as in Hodgkin's disease, the precise identity of the cells remains in doubt. Monolayer tissue cultures derived from Hodgkin's disease tumours and maintained as established cell lines have proven amenable to a variety of cytogenetic, immunological, enzymatic, and ultrastructural studies. Tissue culture experiemnts, in conjunction with meticulous immunological studies of individual Reed-Sternberg cells from non-cultured tumours, suggest that neoplastic cells of Hodgkin's disease are related to, and possibly derived from, cells of the monocyte-macrophage system. The lymphocytes that comprise an integral part of the cellular proliferation and form the basis for histological subclassification of the tumour could be a manifestation of cell-mediated immunity against this non-lymphoid malignant cell. The immunodeficiency of patients with untreated Hodgkin's disease of limited anatomical extent is not the primary event of the disorder and probably not related to the site at which the aetiological agent acts. The deficit does not result solely from impaired T-cell function and appears to arise as a consequence of excessive suppressor cell activity. Inhibitory monocyte-lymphocyte interactions may be one of the causes of defective cell-mediated immunity in Hodgkin's disease. The possible significance of elevated levels of circulating immune complexes in the serum of patients with Hodgkin's disease is indicated by the finding that such complexes react with cells of long-term monolayer tissue cultures derived from the tumour. Circulating immune complexes may be one source for intracellular immunoglobulin in non-cultured Hodgkin's disease cells. The presence of polyclonal immunoglobulin G on the membrane and within the cytoplasm of Reed-Sternberg cells could be due to in vivo binding and ingestion of immune complexes by such cells. The specificity of the interaction between soluble complement-containing immune complexes and neoplastic cells of Hodgkin's disease depends on the nature of the complexed antigen. The complexes could non-specifically attach via an Fc receptor or, if the complexed antigen is identical to a tumour cell antigen, the binding could be specific. If the immune complexes are tumour specific they could provide a source for isolation and identification of tumour-associated antigens. However, the aetiological significance of antigens and putative oncogenic viruses thus far identified in association with Hodgkin's disease remains to be clarified.

Elevated titer of antibodies to Simian sarcoma virus envelope antigen (gp70) and normal response to influenza virus in untreated Danish Hodgkin's patients

Untreated Danish Hodgkin's disease (HD) patients and paired age- and sex-matched controls were tested for serum antibodies to Epstein-Barr virus (EBV), six strains of influenza virus and Simian sarcoma virus/Simian sarcoma-associated virus [SSV(SSAV)] antigens. HD sera showed significantly elevated titers against EBV and both increased incidence and mean titer of antibodies to the envelope glycoprotein of SSV(SSAV), whereas testing against the influenza viruses revealed no differences between HD and controls. A focus reduction assay demonstrated a low incidence in HD and controls of sera with neutralizing effects against SSV(SSAV) and the "baboon" C-type virus component of the human HL-23 virus complex, which seemed coupled to HL-A type W19.

Hodgkin's disease in patients with previous infectious mononucleosis

Patients with a positive reaction to the Paul-Bunnell test in the period 1961-72 were identified at nine different laboratories in Norway and matched against cases of malignant lymphoma registered at the Cancer Registry of Norway in the period 1961-75. Among 5,840 patients having a positive Paul-Bunnell test a total of six developed malignant lymphoma, three of these more than 1 year after the positive Paul-Bunnell test. The expected number of malignant lymphoma was 2.04. Of the six lymphoma cases, five were classified as Hodgkin's disease (HD). The present investigation agrees well with the findings of other epidemiological studies. There seems to be a small excess in incidence of HD among patients with previous infectious mononucleosis (IM), but both diagnostic problems and possible confounding factors must be taken into account before a possible causal association is considered.

Longitudinal study of Epstein-Barr virus antibody titers and excretion in pediatric patients with Hodgkin's disease

Nineteen pediatric patients with Hodgkin's disease (HD) who had experienced primary Epstein-Barr virus (EBV) before, or in one case after, diagnosis, were studied longitudinally for changes in the titers and spectra of EBV-related antibodies, excretion of EBV into the oropharynx, the number of EBV-carrying lymphoid cells in the peripheral blood, and clinical signs and symptoms suggestive of reactivation of the latent virus. The incidence and geometric mean titers of IgG antibodies to viral capsid antigen (VCA) in the HD patients at the time of diagnosis and in the controls were similar. The anti-VCA titers of the patients rose above control levels during and after therapy and remained elevated for up to 7 years of observation. At no time were heterophil or VCA-specific IgM antibodies detected. Antibodies to EBV-induced early antigens were more common in patients (ultimately 80%) than in controls (9%). In contrast, antibody levels to EBV-associated nuclear antigen were disproportionally low in the patients. Excretion of EBV was noted at increased frequency in the patients but the number of circulating, EBV-carrying lymphoid cells was the same as in controls. No discrete clinical syndrome was associated with rising antibody titers or viral excretion. While these results are best explained by a presumed reactivation of the persistent EBV infection by immunosuppressive effects of HD or its therapy, they have not provided direct evidence for this suggestion.

EBV antigens in lymphocytes of patients with exudative tonsillitis, infectious mononucleosis and Hodgkin's disease

A protocol utilizing isokinetic gradients to isolate human lymphocytes is combined with another that purifies the C3 receptor-bearing B lymphocyte subpopulation, thus enriching the EB virus genome-carrying population. Also, rabbit antisera were prepared to the Epstein-Bar virus nuclear antigen (EBNA) and the early antigen (EA) and utilized in an indirect immunofluorescence test (IIT) to detect these antigens in human lymphocytes isolated from various disease states. Using these methods we demonstrated excellent correlation between standard methods previously employed to detect EB virus-coded antigens and our IIT employing xenogenic antisera. Such tests were done on lymphoblastoid cell lines as well as lymphocytes isolated directly from patients with EB virus lymphoproliferative diseases. Human palatine tonsil-derived lymphocytes from children with exudative tonsillitis and peripheral blood lymphocytes of infectious mononucleosis contained only EBNA in C3 receptor-bearing B lymphocytes. However, patients with lymphoproliferative disorders, including Hodgkin's disease, harbored in their spleens and lymph nodes lymphocytes producing both EBNA and EA.