Acellular filtrate of a microbial-based cleaning product potentiates house dust mite allergic lung inflammation

Abstract

Microbial-based cleaning products (MBCPs) contain bacteria and chemical constituents. They are used in consumer applications such as odor reduction, unclogging drains, and surface cleaning. To determine the capacity of a model MBCP to contribute to acute allergic lung inflammation, a two-week repeated exposure regimen was used. Mice were exposed by endotracheal instillation to saline alone, MBCP alone, house dust mites (HDM) alone, or sequentially (i.e., MBCP followed by HDM, HDM followed by MBCP, or HDM + MBCP followed by HDM). Both whole MBCP and acellular MBCP filtrate were investigated, and showed minimal differences in the endpoints examined. HDM exposure caused pulmonary perivascular inflammation, bronchiolar mucous cell metaplasia, elevated bronchoalveolar lavage fluid (BALF) eosinophils, and HDM-specific IgG1. For MBCP, notable changes were associated with sequential exposures. MBCP/HDM caused elevated T2 cytokines in BALF, and elevated neutrophils, eosinophils and IL-5 in peripheral blood. Co-administration of MBCP and HDM followed by HDM resulted in elevated blood and BALF eosinophils and HDM-specific IgE and IgG1. These results demonstrated that acellular MBCP filtrate, and not bacteria within MBCPs, potentiated the acute allergic inflammation to HDM. This methodology could be extended to investigate chronic allergic inflammation and inflammatory potential of other MBCPs and biotechnology products with complex compositions.

Adverse Effects of Fine-Particle Exposure on Joints and Their Surrounding Cells and Microenvironment

“…After fine-particle inhalation, a large number of resident pulmonary inflammatory cells are activated, and more immune cells are recruited, leading to continuous pulmonary inflammation. However, systemic inflammation is subsequently induced through stimulation of the production and activation of more immune cells, such as granulocytes, lymphocytes, and, particularly, macrophages in bone marrow and spleen. − As a result, complications including arthritis occur at the extra pulmonary sites. In this section, we discuss the processes and mechanisms involved in the interplay between fine-particle-induced systemic inflammation and the injuries in joints.…”