Systematic Analysis Of T Cell Receptor And B Cell Receptor Repertoire In Patients With Single And Multiple Primary Lung Cancer

Lung cancer is a malignant tumor that endangers human health worldwide,and its morbidity and mortality rank first.For the early diagnosis and clinical treatment of lung cancer,it is of great significance to study the mechanism of occurrence and development of lung cancer and find molecular markers for early diagnosis of lung cancer.Studies have shown that in advanced lung adenocarcinoma,the peripheral blood TCR repertoire may reflect the host’s antitumor ability.A higher density of T cells in the blood indicates better postoperative outcomes.However,the changes of T and B lymphocyte-mediated immune responses and TCR/BCR CDR3 immune repertoire in multiple primary lung cancer and single primary lung cancer are still unclear.Therefore,this study analyzed the characteristics and changes of T and B lymphocyte receptor CDR3 lineages in peripheral blood,normal tissues,and tumor tissues of patients with multiple primary lung cancer and patients with single primary lung cancer by high-throughput sequencing.The somatic hypermutation and class-switched recombination of cell-produced antibody heavy chains were further investigated,the significant changes in the immune repertoire in patients with lung cancer provide a certain help for the early diagnosis and clinical treatment of lung cancer.The main research contents are as follows:1.First,5 patients with multiple primary lung cancer who met the diagnostic criteria were included in the test group.The peripheral blood,normal tissues and two tumor tissues of the patients were collected,and the total RNA of the samples was extracted.the total RNA was reverse transcribed into c DNA,and the i Repertoire automated system was used to construct the library.The library products were subjected to highthroughput sequencing through the novaseq platform,and bioinformatics analysis was performed on the expression of the seven chains of the immune repertoire in peripheral blood,normal tissue and tumor tissue,the distribution of immunoglobulin subtypes,d50 index,and BCR heavy chain CDR3 region amino acid length distribution,immunoglobulin subtype distribution network.The results show that multiple primary lung cancers highly express BCR-related immune repertoires,and the heterogeneity of tumors hinders the sharing of immune repertoires in peripheral blood and lung tissues.The immunoglobulin subsets of tumor tissue were mainly expressed by Ig A.The d50 index of tumor tissue and peripheral blood was different.The distribution network of immunoglobulin subtypes revealed a large number of clonal mutations in Ig A and Ig G.2.Next,5 single primary lung cancer patients were included in the test group,peripheral blood,normal tissues,and tumor tissues were collected from the patients,total RNA was extracted from the samples,and the total RNA was reverse transcribed into c DNA,and the i Repertoire automated system was used to construct the library.The library were subjected to high-throughput sequencing on the novaseq platform,and bioinformatics analysis was performed on the expression of the seven chains of the immune repertoire in peripheral blood,normal tissues and tumor tissues,the distribution of immunoglobulin subtypes,the amino acid length distribution of the CDR3 region of the BCR heavy chain,the BCR heavy chain V-region gene usage frequency.The results showed that the diversity of seven chains in peripheral blood of patients was significantly different from that of tumor tissue.Ig M accounted for the largest proportion of the normal human BCR immune repertoire and was significantly reduced in tissue samples from patients with single primary lung cancer.IGHV7-4-1 is the V-region gene with the most obvious difference in expression between tumor tissue and peripheral blood.The most frequently expressed V gene in peripheral blood was IGHV4-39.3.Compare the TCR and BCR immune repertoire between the multiple primary lung cancer patient group and the single primary lung cancer patient group.The expression of the seven chains of the immune repertoire of peripheral blood,normal tissues and tumor tissues,the expression of BCR heavy chain isotype,the recombination of antibody class switching,and the use frequency of BCR heavy chain V-J gene combination were compared and analyzed.The results showed that there was no significant difference in the expression of the seven chains between the two groups of patients,and the tumor tissues were mainly expressed BCR repertoire.The expression of IGHA in tumor tissues was up-regulated,while the expression of IGHM was down-regulated.The conversion of IGHA to IGHG3/4 and the conversion of IGHA1/2 to IGH3/4 were increased in the tumor tissues of the two groups of patients.The expression levels of IGHV3-13/IGHJ2,IGHV3-60/IGHJ2,IGHV3-11/IGHJ5,IGHV3-16/IGHJ5,and IGHV3-19/IGHJ5 in No.2 tumor tissue of multiple primary lung cancer were significantly higher than those in No.1 tumor tissue of multiple primary lung cancer.Compared with the combination of V-J genes in two tumor tissues of patients with multiple primary lung cancer,we found that in single primary lung cancer tumor tissues,the expression of IGHV3-71/IGHJ3,IGHV3-47/IGHJ2,IGHV3-35/IGHJ2,and IGHV3-16/IGHJ2.The expression level of IGHV3-6/IGHJ2 was decreased to none.