Natural killer and natural killer T-like cells in splenectomised patients

Abstract

Introduction: Natural killer cells (NK cells) present a unique ability to recognize and kill cells infected with a variety of pathogens, regardless of prior immunization. Natural killer T-like cells (NKT Aim of the study was to estimate the impact of splenectomy on postoperative quantitative changes of NK cells (CD3-/CD16+CD56+) and NKT-like cells (CD3+/CD16+CD56+) as two important lymphocyte subsets involved in host defence against various pathogens. Material and methods: Assessment of NK and NKT-like cells was performed by the flow cytometry in a group of 100 splenectomised patients and 20 healthy volunteers. Results: Patients with secondary asplenia displayed a decreased ratio of NK cells (CD3-/ CD16+CD56+) (p = 0.012) and a higher ratio of NKT-like cells (CD3+/CD16+CD56+) (p = 0.001) in comparison to controls. Patients who underwent elective splenectomy presented a higher amount of NK cells (CD3-/CD16+CD56+) than those with post-traumatic spleen removal (p = 0.035). The time since surgery negatively correlated with NK cells counts (CD3-/CD16+CD56+). In those patients who noticed increased susceptibility to infections, NK cells number (CD3-/CD16+CD56+) was lower (p = = 0.007) than in those patients who did not observe any change in prevalence of infections. Moreover, those patients who noticed an increased infection rate had higher frequencies of NKT-like cells (CD3-/ CD16+CD56+) comparing to those who did not observe any change in the prevalence of infections (p = 0.006). Conclusions: This study provides a further piece of information on the complex immune disturbances in splenectomised individuals leading to the increased risk of bacterial infections. Results obtained suggest that monitoring of NK and NKT-like cells number may provide useful information for determining asplenia-related immunosuppression.

Subpopulations of natural killer-T-like cells before and after surgical treatment of laryngeal cancer

“…A commitment of iNKT cells to immune control is connected with indirect and direct involvement [ 9 ]. NKT cells connect innate and adaptive immunity [ 10 ]. iNKT cells secrete cytokines, which have pro-inflammatory and anti-inflammatory effects [ 4 , 11 ].…”

“…In animal models the significance of iNKT cells in various diseases including cancer has been shown. iNKT may be associated with the pathogenic role in infectious diseases, autoimmunity, and cancer [ 8 , 10 ]. Many tumour cells decrease levels of cancerous antigens, major histocompatibility complex, and costimulatory molecules.…”

“…Those cells respond to the presence of cancer cells. However, iNKT cells are impaired and their functionality is abnormal [ 4 , 10 , 13 ]. In patients with various malignant diseases a decreased number and reduced function of iNKT cells was observed upon activation [ 9 ].…”