Compromised activity of natural killer cells in diffuse large b-cell lymphoma is related to lymphoma-induced modification of their surface receptor expression.

While natural killer (NK) cells are essential players in detection and elimination of malignant cells, these surveillance properties can be compromised by cancer cells. Since NK cell education primarily occurs in the bone marrow and lymphoid tissue, this process might be particularly affected by their infiltration with lymphoma cells. This study aimed to explore functional properties of diffuse large B-cell lymphoma (DLBCL) patient NK cells, which could potentially promote tumour immune evasion and disease propagation.NK cells isolated from the peripheral blood (PB) of 26 DLBCL patients and 13 age-matched healthy controls (HC) were analysed. The cytotoxic CD56dim subtype was the only one identified in patients. Compared to HC, patient cells demonstrated low levels of inhibitory CD158a/b along with decreased expression of activating NKG2D and CD161 and increased inhibitory NKG2A levels. Patient NK cell cytotoxic activity was impaired, as were their degranulation and inflammatory cytokine production, which partially recovered following non-receptor-dependant stimulation.The phenotypically skewed and restricted population of patient NK cells, along with their blunted cytotoxic and immune-regulatory activity, appear to be driven by exposure to lymphoma environment. These NK cell functional aberrations could support lymphoma immune evasion and should be considered in the era of cellular therapy.

Intraoperative bleeding during open flap debridement and regenerative periodontal surgery.

BACKGROUND: The objective of this study was to measure the intraoperative bleeding during periodontal flap surgery. METHODS: Patients scheduled for periodontal surgery were recruited for this study. Data regarding smoking habits, general health, and medications were collected. The amount of the local anesthetic that was injected was then recorded, as well as the number of teeth in the operative field and the duration of the procedure. During surgery, the liquids from the oral cavity were suctioned and collected into a sterile empty vial. To calculate the net amount of blood volume in the liquids, colorimetric assay using capillary blood fructosamine as a reference molecule was used. RESULTS: Twenty-six patients were included in this study. The amount of blood lost during the procedure ranged from 6.0 to 145.1 mL, with an overall mean of 59.47 ± 38.2 mL. Patients taking aspirin (acetylsalicylic acid) showed mean blood loss of 43.26 ± 31.5 mL, whereas the mean blood loss among patients that did not use this medication was higher (65.4 ± 39.4 mL) but not statistically significant. Local anesthetic amount, surgical field size, and the operation duration did not relate to blood-loss volume. The mean blood loss among current smokers was significantly higher (96.47 ± 44.2 mL) compared to former (12 ± 8.4 mL) or never (54.74 ± 30.5 mL, P = 0.011) smokers. CONCLUSION: The results of the current study support previous papers and confirm that blood loss during periodontal surgery is minimal.