ABSTRACT
Objective:To investigate the correlation between preterm infants with brain injury and the proportion of lymphocyte subsets, especially γδ-T cells in the postnatal peripheral blood, and to determine the predictive potential of γδ-T cells in the early peripheral blood in brain injury.Methods:It was a prospective study involving 106 preterm infants with gestational age less than 34 weeks who were delivered in the Department of Neonatology, the Third Affiliated Hospital of Zhengzhou University from January 1, to June 1, 2021.Relative levels of γδ-T , CD4 + T, CD8 + T, CD3 + T and total lymphocyte subsets in peripheral blood collected within the first 24 hours after birth were measured by flow cytometry.Recruited infants were divided into brain injury group (36 cases) and non-brain injury group (70 cases) according to serial cranial ultrasound and magnetic resonance imaging(MRI) at the corrected gestational age of 36-37 weeks.Differences in general conditions and the proportion of lymphocyte subsets between groups were compared by the t-test or Chi- square test.Patients in brain injury group were further divided into intracranial hemorrhage(ICH) group(8 cases), periventricular leukomalacia (PVL) group (6 cases)and diffuse white matter damage (WMD) group(22 cases). The proportion of lymphocyte subsets among the different groups was compared by One- Way ANOVA, followed by the LSD- t test. Results:The proportion of γδ-T cells in postnatal peripheral blood of preterm infants at 24 hours after birth in brain injury group was significantly lower than that of non-brain injury group [(0.09±0.12)% vs.0.15±0.13)%, t=-2.445, P=0.016]. No significant differences in the proportion of the CD4 + and CD8 + T cell subsets were found between them.Both preterm infants in PVL group and WMD group had a significantly lower proportion of γδ-T cells at 24 hours after birth compared to that of the non-brain injury group [(0.03±0.05)%, (0.07±0.09)% and (0.15±0.13)%], respectively, ( t=-2.190, -2.659, all P<0.05). Conclusions:γδ-T cells in early postnatal peripheral blood may be involved in the development of brain injury in preterm infants and they had early predictive value for preterm infants at high risk of brain injury, especially the leukomalacia and diffuse white matter injury.