OBJECTIVETo investigate the expression of programmed death-1 (PD-1) and programmed death ligand-1(PD-L1) in peripheral T-lymphocytes from patients with chronic periodontitis and its significance and to clarify its role in the development of chronic periodontitis.

METHODSA total of 73 subjects were included in the study and divided into three groups, chronic periodontitis(30 cases), chronic gingivitis(25 cases) and 18 healthy controls. The peripheral blood was collected and PD-1/PD-L1 expression in the surface of CD(+)4 T lymphocytes and CD(+)8 T lymphocytes was examined by flow cytometry. Blood samples from 16 chronic periodontitis patients were collected at week 0 and 6 after initial therapy for 6 weeks and PD-1 and PD-L1 expression in the surface of CD(+)4 and CD(+)8 T lymphocytes was also determined by flow cytometry. The data were statistically analyzed.

RESULTSThe percentage of PD-1 expression in CD(+)4 and CD(+)8 T lymphocytes of chronic periodontitis group[(16.7 ± 5.5)%,(20.8 ± 5.1)%]and chronic gingivitis group[(14.2 ± 6.1)%,(14.5 ± 4.3)%]were higher than that of healthy controls[(9.5 ± 2.1)%, (8.1 ± 1.9)%](P < 0.05). The percentage of PD-L1 expression in CD(+)4 and CD(+)8 T lymphocytes of chronic periodontitis group[(24.2 ± 7.1)%,(15.3 ± 6.8)%]and chronic gingivitis group[(12.4 ± 6.0)%,(11.2 ± 5.5)%]were higher than that of healthy controls[(4.7 ± 1.2)%, (3.2 ± 2.3)%] (P < 0.05). The percentage of PD-1/PD-L1 expression in CD(+)4 T lymphocytes and CD(+)8 T lymphocytes of the chronic periodontitis group were significantly decreased after initial therapy(P < 0.05).

CONCLUSIONSThe expression of PD-1 and PD-L1 in peripheral CD(+)4 T lymphocytes and CD(+)8 T lymphocyte of chronic periodontitis patients was up-regulated and was associated with periodontal condition. The initial therapy reduced the expression of PD-1 and PD-L1.

B7-H1 Antigen ; biosynthesis ; Case-Control Studies ; Chronic Periodontitis ; immunology ; metabolism ; Flow Cytometry ; Humans ; Programmed Cell Death 1 Receptor ; biosynthesis ; T-Lymphocytes ; Up-Regulation

Apoptosis ; Cardiopulmonary Resuscitation ; Humans ; Out-of-Hospital Cardiac Arrest ; Programmed Cell Death 1 Receptor/biosynthesis* ; Return of Spontaneous Circulation ; Th1 Cells ; Th2 Cells

OBJECTIVETo clone human PD-1 gene, construct a prokaryotic expression plasmid and express in E. coli.

METHODSThe human PD-1 cDNA was cloned by RT-PCR from the total RNA, which was extracted from peripheral blood lymphocyte cell of the patient with chronic hepatitis B. Recombinant PD-1 protein was been expressed and purified after the prokaryotic expression plasmid had been constructed. It was identified by SDS-PAGE, DNA sequencing and amino acid sequencing.

RESULTSThe PD-1 gene was cloned and confirmed by DNA sequencing. The recombinant protein was expressed in E. coli. The purified protein was obtained, then been confirmed by amino acid sequencing.

CONCLUSIONThe human PD-1 gene was successfully cloned and expressed in E. coli, which lays the foundation for further study on the function and application of PD-1.

Amino Acid Sequence ; Antigens, CD ; biosynthesis ; chemistry ; genetics ; isolation & purification ; Apoptosis Regulatory Proteins ; biosynthesis ; chemistry ; genetics ; isolation & purification ; Cloning, Molecular ; Electrophoresis, Polyacrylamide Gel ; Escherichia coli ; genetics ; Genetic Vectors ; genetics ; metabolism ; Humans ; Polymerase Chain Reaction ; Programmed Cell Death 1 Receptor ; Prokaryotic Cells ; metabolism ; Sequence Alignment ; Sequence Analysis, DNA