Immune responses in women with periodontitis and preterm low birth weight: Levels of CD4+ and CD8+ T cells in gingival granulation tissue

•Macrophage levels in the gingival tissue of mothers with PLBW group were higher than healthy term and healthy control groups.•The increase of CD8+ T lymphocytes and CD4+/CD8+ ratio in maternal gingival tissue seems to be a risk factor of perinatal complications.•The number of CD8+ T lymphocytes and macrophages significantly increased in periodontitis. Preterm Low-Birth-Weight (PLBW) is frequently associated with periodontal disease. However, the mechanism is still unknown. The present study was performed to examine the possible link between periodontal infections and PLBW in post-partum women utilizing clinical parameters and CD4+ and CD8 + T lymphocytes ratio in gingival granulation tissue. The tissues used in this study consisted of 35 gingival granulation tissue biopsies from 35 mothers of healthy infants (HTBW), 35 biopsies of gingival granulation tissue from 35 mothers of PLBW within one month postpartum and gingival tissue biopsies from 7 control individual with no periodontal disease (HC). CD4+ and CD8 + T lymphocyte ratios in a unit area of the gingival granulation tissue were determined by hystometrically. Statistical analysis was performed by using Kruskal-Wallis and Mann-Whitney U tests. CD8 + T lymphocytes were more prevalent in the PLBW group than in the HTBW and HC group (P