Antibiotic choice can alter host inflammation during invasive bacterial infections. Previous studies of gram-negative organisms concluded that antibiotic-mediated release of bacterial cell wall components amplifies inflammation. Less has been reported about antibiotic effect on gram-positive organisms. This study explored the hypothesis that Streptococcus pneumoniae would induce greater macrophage inflammatory mediator production when killed with cell wall active antibiotics rather than protein synthesis inhibitors. Stimulation of RAW 264.7 murine macrophages with pneumococci and oxacillin led to significantly higher inducible nitric oxide synthase (iNOS) and tumor necrosis factor (TNF) accumulation than did the same concentrations of pneumococci and clindamycin. Neither antibiotic alone or in combination with lipopolysaccharide acted directly on macrophages to modify the immune response. Endotoxin contamination did not confound the results, as preincubation with polymyxin B did not change iNOS or TNF protein levels. Thus, the antimicrobial mechanism of action affects macrophage inflammatory mediator production after stimulation with pneumococci.
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http://dx.doi.org/10.1086/315861 | DOI Listing |
Alzheimers Dement
December 2024
Good T Cells, Seoul, Mapo-gu, Korea, Republic of (South); YONSEI University, Seoul, Seodaemun-gu, Korea, Republic of (South).
Background: Neurodegenerative diseases, including Alzheimer's disease (AD), have been long thought to be independent of the peripheral immune system, but their pathogenesis status is functionally influenced by various T cell subsets in the periphery. Especially Treg cells are emerging as an important dynamic population in the brain, but the detailed immunological molecular and cellular processes are poorly characterized METHOD: We reported that the cell surface protein Lrig1 is enriched in Treg cells and is an essential regulator of the functions of Treg cells in vitro and in vivo. To evaluate the functional importance of Treg cells in AD pathogenesis, the modulating mAb specific to Lrig1 (GTC 310-01) via intravenous injection route was administered into 5xFAD or 6xTg mice, the genetic mouse model of AD, and the various AD symptoms were investigated.
View Article and Find Full Text PDFInt J Med Sci
January 2025
Department of Respiratory and Critical Medicine, the Eighth Affiliated Hospital, Sun Yat-Sen University, Shenzhen 518000, Guangdong Province, China.
Chronic Obstructive Pulmonary Disease (COPD) is a heterogeneous respiratory disorder characterized by persistent airflow limitation. The diverse pathogenic mechanisms underlying COPD progression remain incompletely understood. Macrophages, serving as the most representative immune cells in the respiratory tract, constitute the first line of innate immune defense and maintain pulmonary immunological homeostasis.
View Article and Find Full Text PDFInt J Biol Sci
January 2025
Department of Respiratory and Critical Care Medicine, National Clinical Research Center of Respiratory Disease, Key Laboratory of Pulmonary Diseases of Health Ministry, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
As a leading cause of morbidity and mortality, fibrosis is the common pathway of various chronic inflammatory diseases in organs and causes death in a large number of patients. It can destroy the structure and function of organs and ultimately lead to organ failure, which is a major cause of disability and death in many diseases. However, the regulatory mechanism of organ fibrosis is not well clear and the lack of effective drugs and treatments, which seriously endangers human health and safety.
View Article and Find Full Text PDFCytotechnology
February 2025
Department of Oral Biology, University Clinic of Dentistry, Medical University of Vienna, Sensengasse 2a, 1090 Vienna, Austria.
Mechanical and thermal cell damage can occur due to invasive procedures related to drilling, the insertion of dental implants, and periodontal treatments. Necrotic cells release the content of their cytoplasm and membrane fragments, thereby signaling the need for repair, which includes bone resorption by osteoclasts and inflammation. Here we screened lysates from human gingival fibroblasts, HSC2 and TR146 oral squamous carcinoma cell lines, as well as murine IDG-SW3 osteocytic and RAW264.
View Article and Find Full Text PDFZhonghua Wei Zhong Bing Ji Jiu Yi Xue
December 2024
Department of Anesthesiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu, China. Corresponding author: Rao Zhuqing, Email:
Macrophages are widely distributed in peripheral blood, lungs, liver, brain, kidneys, skin, testes, vascular endothelial cells, and other parts of the body. As sentinel cells of innate immunity, they play an important role in the occurrence and development of sepsis. Recent research in immune metabolism has revealed the complicated relationship between specific metabolic pathways of macrophages and their phenotype and function in sepsis.
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