[21]

[21]. Our study highlighted the limitations of the immunofluorescence assay (IFA) using viral capsid antigen (VCA) and early antigen (EA) in patients under 30 years of age. and 30 years old,p< 0.01; 1529 and 30 years old,p< 0.05). Differences were also noted in the titers of IgA anti-VCA and anti-EA antibodies across the three age groups. Some patients under the age of 30 with detectable IgG anti-VCA antibodies had undetectable IgA anti-VCA antibodies. These patients had a strong anti-DNase IgA response. However, older individuals had a higher level of anti-DNase IgG. Before treatment, children had strong DNase reactivity as indicated by specific IgA antibodies. Young adults had high IgA anti-DNase response, but the elderly (90.9%) had a lower response for these antibodies. Following p53 and MDM2 proteins-interaction-inhibitor racemic therapy, the children p53 and MDM2 proteins-interaction-inhibitor racemic retained high levels of IgA anti-DNase antibodies, and 66% of the young adults demonstrated robust antibody reactivity against DNase. In contrast, IgG responses to anti-DNase were low in children. This study demonstrated the utility of anti-DNase responses in the diagnosis and prognosis of NPC. Keywords:undifferentiated nasopharyngeal carcinoma, diagnosis, EBV, VCA, EA, DNase == 1. Introduction == Epstein-Barr virus (EBV), a lymphotropic herpesvirus, is known for causing infectious mononucleosis and malignant lymphomas. This virus is also strongly associated with undifferentiated nasopharyngeal carcinoma (UCNT), a common tumor type in Algeria that affects children, young adults, and adults. In contrast, just the adult peak is seen in Asia. The diagnosis of UCNT often relies on the detection of IgA antibodies against EBV viral capsid antigen (VCA) and early antigen (EA), although molecular techniques are recognized for their enhanced sensitivity [1]. VCA-IgA antibodies are uncommon in healthy people, giving them a dual function in the diagnosis and prognosis of UCNT [2,3,4]. However, a significant number of North African individuals under the age of thirty have undetectable serum VCA-IgA levels [5,6,7]. This suggests a congenital IgA deficiency, occurring in approximately 1 out of every 700 BCL3 Caucasians [8]. Several other factors may contribute to this phenomenon, including recent EBV infections in the region, the diversity of EBV strains prevalent among younger individuals in North Africa, or the p53 and MDM2 proteins-interaction-inhibitor racemic influence of individual genetic factors that can impact an individuals immune response to infections. Advancements in EBV biomarkers have been pursued to enhance the diagnosis of nasopharyngeal cancer (NPC) [9,10]. The specificity and sensitivity of EBV testing using single p53 and MDM2 proteins-interaction-inhibitor racemic markers have been debated [11,12]. Some EBV markers were proposed to improve the diagnosis and prognosis of NPC. Particularly, the BARF1 protein has been identified in the serum and saliva of North African NPC patients, with lower levels of anti-BARF1 antibodies observed in these patients p53 and MDM2 proteins-interaction-inhibitor racemic [13]. The quantification of circulating EBV DNA has emerged as a method with superior accuracy in diagnosing and monitoring NPC [14]. However, establishing a consensus on the lowest limit of plasma EBV detection remains a challenge [15,16]. Additionally, the BGLF5 gene product (DNase) has shown promise as a robust marker. NPC sera contained high levels of antibodies against DNase, with fluctuations during periods of remission and relapse [17,18,19]. The baculovirus expression system has been used for the expression of recombinant DNase within insect cells [20]. The product of this expression system has shown increased IgA synthesis in NPC patients, as demonstrated by Chang et al. [21]. Our study highlighted the limitations of the immunofluorescence assay (IFA) using viral capsid antigen (VCA) and early antigen (EA) in patients under 30 years of age. We used the immunoblot enhanced chemiluminescence (ECL) assay to demonstrate its ability to detect antibodies against DNase in all patients. This tests remarkable sensitivity and specificity make it helpful for providing significant assistance and serving as a complementary tool for an accurate diagnosis. == 2. Materials and Methods == == 2.1. Patients and Controls == Between 2012 and 2021, a total of 622 cases of undifferentiated nasopharyngeal cancer (UCNT) were classified histologically as NPC tumors according to the World Health Organization classification [22] and staged according to the 7th Edition American Joint Committee on.