Epstein‐barr virus‐specific IgA serum antibodies as an outstanding feature of nasopharyngeal carcinoma

Abstract

Stimulated by a report on elevated IgA levels in nasopharyngeal carcinoma (NPC), we tested a total of 372 sera from patients with NPC, other carcinomas of head and neck or elsewhere, Burkitt's lymphoma (BL), infectious mononucleosis (IM) or healthy controls. The sera were titrated in indirect immunofluorescence tests for IgA antibodies to Epstein-Barr virus (EBV) capsid antigen (VCA) and to the diffuse (D) or restricted (R) components of the EBV-induced early antigen (EA) complex. The results proved NPC to be outstanding in that prior to therapy 93% of the patients tested revealed IgA antibodies to VCA and 73% to D, often at high titers which occasionally matched the corresponding IgG antibody levels. The EBV-specific IgA titers increased from stages I or II to stages III or IV; i.e. with the total tumor burden. Conversely, many of the NPC patients examined 2-6 years after initial therapy had only low levels of EBV-specific IgA or none at all, and the majority of those with high titers were known to have residual or recurrent disease. In contrast to untreated NPC patients, less than 5% of 73 patients with other carcinomas or of 76 healthy donors revealed VCA-specific IgA and even fewer EA-specific IgA; only 28% and 4% of 54 BL patients tested at admission had IgA antibodies to VCA and R, respectively, and 38% and 3% of 37 IM patients showed transient VCA- or D-specific IgA responses, all at generally low titers. While sera from untreated NPC patients often contained IgA antibodies also to herpes simplex type 1 virus, their incidence and range of low titers were similar to those obtained with sera from patients with other carcinomas or from healthy donors. It thus appears that the elevated IgA levels in NPC might be due to EBV-specific antibodies. Possible reasons for this unique response in NPC have been discussed.

Circulating Epstein–Barr virus microRNAs miR‐BART7 and miR‐BART13 as biomarkers for nasopharyngeal carcinoma diagnosis and treatment

“…48 Early recognition of disease onset remains an important factor in survival, as the majority of cases are at an advanced stage upon diagnosis. One of the hallmarks of NPC is the association with EBV (12,13). While the mechanism by which EBV contributes to the initiation or progression of NPC is still not understood, numerous studies have focused on using EBV as a biomarker for recognition, and even therapy, of NPC.…”

“…11,12 It is notable that EBV is rarely detected in noncancerous epithelial cells, even in the areas adjacent to NPC. 13 EBV is thus an excellent biomarker for NPC diagnosis.…”

Factors affecting serum IgA antibody to Epstein-Barr viral capsid antigens in nasopharyngeal carcinoma

“…These reactivities are detected less frequently and occur at lower titres in sera from patients with Burkitt's lymphoma (BL) and infectious mononucleosis (IM). Both BL and IM, like NPC, are closely associated with EBV, such that all 3 groups of patients have comparably high titres of IgG antibodies against VCA (Henle and Henle, 1976). Moreover, EBV is a ubiquitous virus, such that all the healthy Chinese subjects which served as one of the control groups in our previous studies had serum IgG antibodies against VCA, but none had detectable IgA antibodies .…”

“…Serum IgA concentration was found to be significantly higher in NPC patients than in control subjects (Wara et al, 1975;Ho et al, 1976). Henle and Henle (1976) reported that NPC patients have high titres of IgA antibody against viral capsid antigen (VCA) (Henle and Henle, 1966) and early antigens (EA) (Henle et al, 1970). These reactivities are detected less frequently and occur at lower titres in sera from patients with Burkitt's lymphoma (BL) and infectious mononucleosis (IM).…”

Epstein-Barr virus in nasopharyngeal and salivary gland carcinomas of Greenland Eskimoes

“…It was rapidly shown thereafter that NPC patients had elevated titres of IgG antibodies to EBV viral capsid antigen (VCA) and to the diffuse (D) component of the early-antigen (EA) complex (Henle et al, 1970(Henle et al, , 1971(Henle et al, , 1977. IgA antibodies to these 2 antigens were also often demonstrable in sera from NPC patients (Henle & Henle, 1976;Henle et al, 1977). This pattern of elevated IgG and IgA antibodies to VCA and EA (D) has been found uniformly in NPC patients, whether from low-or high-risk areas (Henle & Henle, 1976;Henle et al, 1977;de The et al, 1978;Klein, 1979;Lanier et al, 1981).…”