Exposure to welding fumes suppresses the activity of T-helper cells

Knobloch, Jürgen; Casjens, Swaantje; Lehnert, Martin; Yanik, Sarah D.; Koerber, Sandra; Lotz, Anne; Rupp, Jan; Raulf, Monika; Zschiesche, Wolfgang; Weiss, Tobias; Kronsbein, Juliane; Koch, Andrea; Bruening, Thomas und Pesch, Beate (2020): Exposure to welding fumes suppresses the activity of T-helper cells. In: Environmental Research, Bd. 189, 109913

Abstract

Welders have an increased susceptibility to airway infections with non-typeable Haemophihis influenzae (NTHi), which implicates immune defects and might promote pneumonia and chronic obstructive pulmonary disease (COPD). We hypothesized that welding-fume exposure suppresses Th1-lymphocyte activity. Non-effector CD4(+) T-cells from blood of 45 welders (n = 23 gas metal arc welders, GMAW;n = 16 tungsten inert gas welders, TIG;n = 6 others) and 25 non-welders were ex vivo activated towards Th1 via polyclonal T-cell receptor stimulation and IL-12 (first activation step) and then stimulated with NTHi extract or lipopolysaccharide (LPS) (second activation step). IFN gamma and IL-2 were measured by ELISA. In the first activation step, IFN gamma was reduced in welders compared to non-welders and in the GMAW welders with higher concentrations of respirable particles compared to the lower exposed TIG welders. IFN gamma was not influenced by tobacco smoking and correlated negatively with weldingfume exposure, respirable manganese, and iron. In the second activation step, NTHi and LPS induced additional IFN gamma, which was reduced in current smokers compared to never smokers in welders as well as in non-welders. Analyzing both activation steps together, IFN gamma production was lowest in smoking welders and highest in never smoking non-welders. IL-2 was not associated with any of these parameters. Welding-fume exposure might suppress Th1-based immune responses due to effects of particulate matter, which mainly consists of iron and manganese. For responses to NTHi this is strongest in smoking welders because welding fume suppresses T-cell activation towards Th1 and cigarette smoke suppresses the subsequent Th1-response to NTHi via LPS. Both effects are independent from IL-2-regulated T-cell proliferation. This might explain the increased susceptibility to infections and might promote COPD development.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Medizin
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• ISSN: 0013-9351
• Sprache: Englisch