Role of Peripheral Blood Mononuclear Cells in the Predisposition of Obese Individuals to Inflammation and Infection

Abstract

Objective: To compare the production of pro- and anti-inflammatory cytokines by peripheral blood mononuclear cells (PBMC) from obese but otherwise healthy individuals to that of normal-weight volunteers. Methods: 25 healthy normal-weight subjects and 41 obese individuals were enrolled. Weight and height were measured twice. PBMC were examined for their capacity to generate pro-inflammatory (TNF-α, IFN-γ, IL-1β, IL-6, IL-2) and anti-inflammatory IL-10 and IL-1ra) cytokines. Results: PBMC from obese individuals, compared to those from subjects with normal weight showed an increased production of the pro-inflammatory cytokines IL-2 (6.7 ± 0.4. vs. 4.9 ± 0.3 ng/ml; p = 0.003), TNF-α (505 ± 45 vs. 277 ± 32 pg/ml; p = 0.001), and IFN-γ (93.8 ± 6.0 vs. 73.9 ± 2.7 ng/ml; p = 0.0016). However, PBMC from obese individuals produced a lower amount of the anti-inflammatory cytokine IL-10 (651 ±72 pg/ml) versus those from subjects with normal weight (951 ± 133 pg/ml; p = 0.039). Conclusions: The findings imply that obese individuals are in a ‘low-grade inflammatory state', presumed to be connected with metabolic and cardiovascular co morbidities. The surplus of pro-inflammatory cytokines produced by circulating mononuclear cells of obese individuals, together with those secreted by adipocytes and non-fat cells in the adipose tissue, may contribute to the predisposition of obese patients to inflammation and infections.

Decreased expression of microRNA-21 is associated with increased cytokine production in peripheral blood mononuclear cells (PBMCs) of obese type 2 diabetic and non-diabetic subjects

“…To study the role miR-21 in inflammation of PBMCs of obese subjects, we evaluated the inflammatory cytokines production in these cells. First, in consistent with a previous report, PBMCs from obese individuals showed an increased production of the pro-inflammatory cytokines compared with the lean subjects [31]. Furthermore, we found an inverse correlation between miR-21 expression and pro-inflammatory cytokines production from PBMCs of the obese subjects.…”

Peripheral mononuclear blood cells contribute to the obesity-associated inflammatory state independently of glycemic status: involvement of the novel proinflammatory adipokines chemerin, chitinase-3-like protein 1, lipocalin-2 and osteopontin

“…PBMC from obese individuals showed an increased secretion of the pro-inflammatory cytokines tumor necrosis factor (TNF)-a, interferon (IFN)-c and interleukin (IL)-2 as well as a lower production of the anti-inflammatory cytokine IL-10 (Dicker et al 2013). Reportedly, T2D obese patients exhibit higher expression levels of TNF receptor (TNFR)-2 in PBMC compared to normoglycemic obese individuals (Fogeda et al 2004).…”

Specific cellular immune response elicited by the necrotic tumor cell-stimulated macrophages

“…Through cytokines, Th1 and Th2 CD4+ T cells promote cellular and humoral immunity respectively [26,27]. IL-2 and IFN-γ are cytokines for the induction of cellular immunity; on the contrary, IL-4 and IL-10 promote humoral immunity [28][29][30]. Our results show that the splenocytes harvested from the group immunized with necrotic tumor cell-stimulated macrophages produce the high levels of IL-2 and IFN-γ when exposed to H22 cells.…”