Immunoreaction Study Of SALL4,NYESO1,SSX2 And LMP2A Protein In Peripheral Blood Of Patients With Nasopharyngeal Carcinoma

Objective:To investigate the association between nasopharyngeal carcinoma Epstein-Barr virus-associated antigen,tumor-associated antigen,copy number of Epstein-Barr virus and clinical features,analyze the correlation between EB virus copy number and antigen CTL response,and search for T-cell immune markers related to clinical characteristics,in order to provide laboratory evidence for individualized treatment of nasopharyngeal cancer in the future.Methods:61 newly diagnosed NPC patients were enrolled,all patients were pathological confirmed.The frequency and number of SALL4,NYESO1,SSX2 and LMP2A specific cytotoxic immune response were determined using ELISpot assay,at the same time,the PCR method was used to detect the EBV copy number in plasma,analyze the correlations between the above antigen CTL response,EBV copy number and clinical characteristics,and the correlations between EBV copy number and the above-mentioned antigen CTL response.Results:(1)The recognized frequency of SALL4,NYESO1,SSX2 and LMP2A specific T cell response were27.9%,18.0%,11.5%,55.7%,and the magnitudes of them were 47.4,37.5,27.8,142.7 SFC/10~6PBMCs.(2)The recognized frequencies ofSALL4 specific T cell response were40.7%and 17.6%in EBV-negative and EBV-positive respectively,the difference was significant(χ~2=3.993,P=0.046);The magnitude mean ranks of SALL4specific T cell response were 15.5、8.96 and 2.75 SFC/10~6PBMCs in N1、N2 and N3stage,the difference was significant(χ~2=6.402,P=0.041).(3)The magnitude mean rank of SSX2 specific T cell response in>48 years old group was 5.83,was higher than that in≤48 group years old(2.63),the difference was significant(P=0.048).(4)The magnitude mean rank of LMP2A specific T cell responsein female group was24.21,was higher than that in male group(15.76),the difference were significant(P=0.045).(5)The positive rate of EBV in plasma of NPC patients was 55.7%,and the copy number of EBV ranged from 0 to 64030 copies/ml,the median was 498.60 copies/ml and the quartile was87.68 to 3823.5 copies/ml.(6)There is weak negativecorrelation between the magnitude of SALL4 specific T cell response and different EBV copy number in NPC without treatment(r=-0.313,P=0.027).Conclusion:(1)SALL4,NYESO1,SSX2,and LMP2A antigens in nasopharyngeal carcinoma can induce specific immune responses,providing a certain reference value for the selection of immunotherapy targets for nasopharyngeal carcinoma.(2)The above antigen immune response was compared in clinical characteristics and found that the frequency of SALL4-specific immune responses was higher in the EBV-negative group than in the positive group,and the response intensity was in N1>N2>N3;There was a statistical difference in the intensity of SSX2-specific immune responses between different age groups;the intensity of LMP2A-specific immune responses was higher in the female group than in the male group(P=0.045).(3)The positive rate of EBV was 55.7%,compared with the clinical features,the EBV positive rate increased with the increase of T stage,N stage,and clinical stage.The intensity of SALL4-specific immune response in peripheral blood of patients with nasopharyngeal carcinoma was weakly negatively correlated with EBV copy number.