Transition Metal Containing Particulate Matter Promotes Th1 and Th17 Inflammatory Response by Monocyte Activation in Organic and Inorganic Compounds Dependent Manner

Abstract

In recent years, a significant increase in the frequency of disorders caused by air pollutants has been observed. Here we asked whether transition metal-containing particulate matter (TMCPM), a component of air pollution, has an effect on the activity of human CD4+ T cell subsets (Th1, Th2, Th17, and Treg). Peripheral blood mononuclear cells (PBMC) from healthy donors were cultured with or without NIST (SRM 1648a—standard urban particulate matter purchased from the National Institute for Standards and Technology) and LAP (SRM 1648a particulate matter treated within 120 min with cold oxygen plasma) preparations of TMCPM, differing in organic compounds content. Data show that TMCPM treatment increased the level of CD4+ cells positive for IFN-γ and IL-17A, specific for Th1 and Th17 cells, respectively. Moreover, a substantial decrease in frequency of Foxp3 positive CD4+ cells was observed in parallel. This effect was more pronounced for NIST particles, containing more organic components, including endotoxin (LPS - lipopolysaccharide) and required the presence of monocytes. Inactivation of LPS by treatment of TMCPM with polymyxin B reduced the inflammatory response of monocytes and Th subsets but did not abolish this activity, suggesting a role of their inorganic components. In conclusion, treatment of human PBMC with TMCPM skews the balance of Th1/Th2 and Treg/Th17 cells, promoting polarization of CD4+ T cells into Th1 and Th17 subsets. This phenomenon requires activation of monocytes and depends on the organic and inorganic fractions, including endotoxin content in TMCPM, as significantly higher inflammatory response was observed for the NIST comparing to LAP. This observation may shed a new light on the role of TMCPM in development and exacerbation of allergies, inflammatory, and autoimmune disorders.

LPS Response Is Impaired by Urban Fine Particulate Matter

“…The PM group displayed a very different inflammatory pattern from the LPS group, with the increase in circulating leukocytes and lymphocytes, increased BALF and lung parenchyma macrophages, increased levels of IL-5 in the blood serum, and increased levels of IL-4 and IL-17 in the lung parenchyma. Many studies have shown the connection between the concentration of PM 2.5 and the development or exacerbation of allergies and inflammatory/autoimmune disorders [ 7 ].…”

“…Previous studies showed that exposure to air pollution increases the levels of IL-17 and enhances Th17 differentiation through the aryl hydrocarbon receptor (AHR) [ 31 , 32 ]. Moreover, Gałuszka et al [ 7 ] reported that T cells exposed to transition metal-containing particulate matter showed an increase in the proportion of IFN-γ and IL-17A producing cells, with a concomitant decrease in Treg cells. Our results suggest a Th17/Treg imbalance in our animal exposed to PM 2.5 with increased expression of IL-17 in the lung parenchyma and decreased expression of Foxp3 mRNA.…”

“…In humans, chronic exposure to air pollution is associated with decreased lung function [ 3 ], increased risk of developing acute respiratory distress syndrome [ 4 ], chronic asthma, and pulmonary insufficiency [ 5 ], and inflammation has been implicated as the key mechanism of PM-mediated health problems. In addition, PM 2.5 exposure can modulate different inflammatory pathways causing a Th1/Th2 and Th17/Treg imbalance [ 6 , 7 ].…”

Adequate Pollution Management - A Must for Implementation of ‘One Health’ Concept

“…Finding a cure for a disease even if it is an infectious one, cancer or a neurodegenerative means to find its root cause. The onset and the development of diseases like allergic asthma [35][36][37], multiple sclerosis, Alzheimer and Parkinson diseases or different forms of cancer [38][39][40] for example have been intensely studied in last decades in relation to the toxicity of different pollutants and especially in relation to the emitted air-borne particles less than PM 2.5. Next, we will try to offer some more details about them and about how their toxicity manifests by modulating our immunity.…”

Effects of environmental parameters and their interactions on the spreading of SARS-CoV-2 in North Italy under different social restrictions. A new approach based on multivariate analysis

“…These mediators down-regulate the expression of FoxP3 protein, promoting the inhibition of T reg cells and stimulating pro-inflammatory activity of Th17 lymphocytes. These events lead to an exacerbation of tissue inflammation ( Gałuszka et al, 2020 ; Matthews et al, 2016 ). It is well-known that sunlight prevents respiratory tract infection mediated by several viruses, such as the influenza virus ( Walker and Ko, 2007 ; Tseng and Li, 2005 ).…”