Peripheral memory T‐cell profile is modified in patients undergoing periodontal management

Abstract

AimsT‐cells are known to have a role in periodontitis, however, the effect of periodontal therapy on peripheral memory T‐cells is unclear. This study evaluated variation in peripheral memory T‐cells and red complex bacteria in sub‐gingival plaque in patients undergoing periodontal management.MethodsPeripheral blood mononuclear cells and sub‐gingival plaque were collected from 54 periodontitis patients at baseline, 3‐, 6‐ and 12‐months post‐therapy and 40 healthy controls. Periodontitis patients were divided into treatment outcome (TxO) groups based on prevalence of sites with probing depth ≥5 mm as good (<10% of sites), moderate (10–20%) or poor (>20%) at study conclusion. Naïve (TN—CCR7+CD45RA+), central memory (TCM—CCR7+CD45RA−), effector memory (TEM—CCR7−CD45RA−) and effector memory T‐cells re‐expressing CD45RA (TEMRA—CCR7−CD45RA+) were phenotyped using flow cytometry in CD4+, CD8+, CD4+CD8+ and CD4−CD8− T‐cells and red complex bacteria were quantified using qPCR.ResultsAt baseline, periodontitis subjects had significantly greater mean probing depths and Porphyromonas gingivalis proportions, lower TN but higher CD4+ TCM, CD8+ TCM, CD4+CD8+ TEM and CD4−CD8− TEM cell proportions compared to health. Periodontal therapy decreased mean probing depths, P. gingivalis proportions, TEM and CD4+ and CD8+ TCM cells, but increased TN and CD4+ and CD8+ TEMRA cells. The T‐cell profile in the good TxO group showed therapy‐related changes in CD4+ TEM, and CD8+ TN and TEM cells, whereas, no changes were observed in the poor TxO group.ConclusionManagement and the reduction in red complex bacteria were associated with changes in peripheral memory T‐cells in periodontitis.

Circulating inflammatory cell profiling and periodontitis: A systematic review and meta-analysis

“…Further, the percentage of CD8 + T cells and their effector memory (CCR7 − CD45RA − ) was lower after periodontal treatment compared with baseline. The naive cytotoxic T (Tc) cells (CD8 + CCR7 + CD45RA + ) were higher following treatment compared with baseline 46 . Periodontal treatment reduced HLADR‐, CD44‐, CD49d‐, CD62‐expressing CD4 + T cells 123 and effector memory Th cells (CD4 + CCR7 − CD45RA − ), 46 whereas CD4 + , naive Th cells (CD4 + CCR7 + CD45RA + ), and CD4 + CD45RA + cells were increased after the treatment 46,128 …”

“…This review also provides some initial evidence that periodontal treatment alters the proportion and function of circulating inflammatory cells. Suppressive neutrophils, TLR‐expressing monocyte, immunosenescent cytotoxic T cells, naive, central, and effector memory T cells were affected by periodontal treatment 46,121,123,127 . Further improvement in phagocytic activity, chemotactic response, and ROS production of peripheral blood‐derived cells, including neutrophils and monocytes, was noted 61,62,66,96,131 .…”

“…Increased peripheral effector memory Th cells have been linked to faster subclinical atherosclerosis and cardiovascular events 163 . In this review, we identified evidence suggesting that periodontal treatment reduced these T cell subsets 46 . Further research should address the hypothesis that T lymphocyte subsets could be influenced by periodontal treatment and link them to vascular phenotypes including endothelial dysfunction and hypertension.…”

“…Suppressive neutrophils, TLR-expressing monocyte, immunosenescent cytotoxic T cells, naive, central, and effector memory T cells were affected by periodontal treatment. 46,121,123,127 Further improvement in phagocytic activity, chemotactic response, and ROS production of peripheral blood-derived cells, including neutrophils and monocytes, was noted. 61,62,66,96,131 Collectively, this suggests a possible causal association between periodontitis and proportion and function of circulating inflammatory cells.…”

Periodontitis, chronic liver diseases, and the emerging oral‐gut‐liver axis

“…158 In fact, both cytotoxic and helper T cells appear to be altered in the peripheral blood of individuals with severe periodontitis and a recent study noted an increase in the population of both CD8 + CCR7 + and CD4 + CCR7 + central memory T cells. 159 While the total number of CD4 + T cells is increased in individuals presenting with severe periodontitis, these cells exhibit reduced ability to produce IFNγ even after stimulation with pathogens. In addition, the number of circulating CD4 + IFNγ + is also reduced in this patient population.…”