Antibody responses against polypeptide components of Epstein-Barr virus-induced early diffuse antigen in patients with connective tissue diseases

ABSTRACTWHO type III nasopharyngeal carcinoma (NPC) is highly prevalent in Indonesia and 100% associated with Epstein-Barr virus (EBV). NPC tumor cells express viral proteins, including BARF1, which is secreted and is considered to have oncogenic and immune-modulating properties. Recently, we found conserved mutations in the BARF1 gene in NPC isolates. This study describes the expression and purification of NPC-derived BARF1 and analyzes humoral immune responses against prototype BARF1 (B95-8) and purified native hexameric BARF1 in sera of Indonesian NPC patients (n= 155) compared to healthy EBV-positive (n= 56) and EBV-negative (n= 16) individuals. BARF1 (B95-8) expressed inEscherichia coliand baculovirus, as well as BARF1-derived peptides, did not react with IgG or IgA antibodies in NPC. Purified native hexameric BARF1 protein isolated from culture medium was used in enzyme-linked immunosorbent assay (ELISA) and revealed relatively weak IgG and IgA responses in human sera, although it had strong antibody responses to other EBV proteins. Higher IgG reactivity was found in NPC patients (P= 0.015) than in regional Indonesian controls or EBV-negative individuals (P< 0.001). IgA responses to native BARF1 were marginal. NPC sera with the highest IgG responses to hexameric BARF1 in ELISA showed detectable reactivity with denatured BARF1 by immunoblotting. In conclusion, BARF1 has low immunogenicity for humoral responses and requires native conformation for antibody binding. The presence of antibodies against native BARF1 in the blood of NPC patients provides evidence that the protein is expressed and secreted as a hexameric protein in NPC patients.

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Antibody Responses to Epstein-Barr Virus, Human Herpesvirus 6 and Human Herpesvirus 7 in Patients with Chronic Fatigue Syndrome

Intervirology ◽

10.1159/000150450 ◽

1995 ◽

Vol 38 (5) ◽

pp. 269-273 ◽

Cited By ~ 39

Author(s):

Takeshi Sairenji ◽

Koichi Yamanishi ◽

Yoichi Tachibana ◽

Giuseppe Bertoni ◽

Takeshi Kurata

Keyword(s):

Chronic Fatigue Syndrome ◽

Epstein Barr Virus ◽

Human Herpesvirus ◽

Chronic Fatigue ◽

Antibody Responses ◽

Human Herpesvirus 6 ◽

Barr Virus ◽

Fatigue Syndrome ◽

Herpesvirus 6 ◽

Epstein Barr

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Epstein-Barr Virus Infectious Mononucleosis in Children

PEDIATRICS ◽

10.1542/peds.75.6.1011 ◽

1985 ◽

Vol 75 (6) ◽

pp. 1011-1019 ◽

Cited By ~ 1

Author(s):

Ciro Valent Sumaya ◽

Yasmin Ench

Keyword(s):

Infectious Mononucleosis ◽

Epstein Barr Virus ◽

Immunoglobulin M ◽

Antibody Responses ◽

Adult Patients ◽

Nuclear Antigen ◽

Barr Virus ◽

Age Related ◽

Slide Test ◽

Epstein Barr

An investigation was performed to address the need to establish the rate of positive heterophil antibody responses, oropharyngeal isolation of Epstein-Barr virus (EBV), and the evolving pattern of EBV-specific antibody responses among children with documented EBV-infectious mononucleosis. Findings showed that the rate of heterophil antibody responses appeared to increase progressively with advancing age from infancy up to 4 years, after which the rates approached values similar to that reported in young adult patients. The rapid slide test detected a heterophil antibody response as frequently as the Paul-Bunnell-Davidsohn horse cell test, except in children less than 4 years old. The decreased sensitivity found with the rapid slide test in the very young was associated with their less intense heterophil response. The younger group of children also developed a lower acute mean titer and, as a result, a decreased persistence of immunoglobulin M antibody to EBV-capsid antigen, whereas they had more frequent responses to EBV-early antigen directed to restricted component than both the older subjects and adults reported elsewhere. Antibodies to EBV-nuclear antigen, characteristically a late-onset antibody, tended to develop earlier than noted in adult patients. In contrast, the prevalence and continued excretion of EBV from oropharyngeal secretions was similar to that reported in adult patients. It is speculated that these age-related differences in host responses are associated with the ontogeny of the immunologic system.

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