Location
Sydnor Performance Hall, Schewel Hall
Access Type
Campus Access Only
Presentation Type
Oral presentation
Entry Number
95
Start Date
4-16-2026 3:45 PM
End Date
4-16-2026 4:00 PM
School
School of Medicine and Health Sciences
Keywords
Arginase, Macrophage, RAW 264.7, 8 Bromo cAMP
Abstract
Macrophages are a type of white blood cell that have various functional roles in the innate immune system, the body’s first line defense against invading pathogens. Macrophages have two phenotypic forms, M1 and M2 macrophages, which are functionally and metabolically different and respond to different stimuli. Macrophages respond to bacterial products, such as lipopolysaccharide (LPS), by producing inflammatory mediators (M1). Furthermore, macrophages respond to 8 Bromo cAMP (8Br) by producing tissue repair and wound healing properties (M2). Second messenger signaling, like [8Br] cAMP, also plays an important role in the resolution of inflammation and inflammatory mediators. Metabolism plays a large role in macrophage polarization, resulting in the use of different metabolic pathways and metabolic outputs. Understanding metabolic activity and cAMP signaling pathways in macrophages is important to evaluate their functional role in inflammatory responses and resolution. A key metabolic pathway that differs in macrophage phenotypes is the metabolism of L-Arginine. L-Arginine is the substrate for two different enzymes in macrophages: inducible nitric oxide synthase (iNOS) and arginase. Arginase activity is measurable in both LPS and 8Br stimulated RAW 264.7 macrophages. The RAW 264.7 murine macrophage cell line is a standard model for evaluating pro-inflammatory stimuli. It is known that two different isoforms of arginase are expressed in macrophages. 8 bromo cAMP (0 - 1000µM) dose responsively stimulated arginase activity in the presence and absence of 100 ng/mL LPS. 8Br (100µM) combined with 1 ng/mL LPS shows decreased NO response. Continuing experiments are being developed to examine which isoform is both stimulated and measurable in our systems based upon LPS and 8Br alone or given simultaneously. Developing clear protocols for measuring arginase activity can further extend an understanding of the metabolic activity underlying macrophage polarization.
Primary Faculty Mentor(s)
Dr. Freier
Primary Faculty Mentor(s) Department
Biology
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Investigating aringase activity in the murine macrophage RAW 2647 cell line.
Sydnor Performance Hall, Schewel Hall
Macrophages are a type of white blood cell that have various functional roles in the innate immune system, the body’s first line defense against invading pathogens. Macrophages have two phenotypic forms, M1 and M2 macrophages, which are functionally and metabolically different and respond to different stimuli. Macrophages respond to bacterial products, such as lipopolysaccharide (LPS), by producing inflammatory mediators (M1). Furthermore, macrophages respond to 8 Bromo cAMP (8Br) by producing tissue repair and wound healing properties (M2). Second messenger signaling, like [8Br] cAMP, also plays an important role in the resolution of inflammation and inflammatory mediators. Metabolism plays a large role in macrophage polarization, resulting in the use of different metabolic pathways and metabolic outputs. Understanding metabolic activity and cAMP signaling pathways in macrophages is important to evaluate their functional role in inflammatory responses and resolution. A key metabolic pathway that differs in macrophage phenotypes is the metabolism of L-Arginine. L-Arginine is the substrate for two different enzymes in macrophages: inducible nitric oxide synthase (iNOS) and arginase. Arginase activity is measurable in both LPS and 8Br stimulated RAW 264.7 macrophages. The RAW 264.7 murine macrophage cell line is a standard model for evaluating pro-inflammatory stimuli. It is known that two different isoforms of arginase are expressed in macrophages. 8 bromo cAMP (0 - 1000µM) dose responsively stimulated arginase activity in the presence and absence of 100 ng/mL LPS. 8Br (100µM) combined with 1 ng/mL LPS shows decreased NO response. Continuing experiments are being developed to examine which isoform is both stimulated and measurable in our systems based upon LPS and 8Br alone or given simultaneously. Developing clear protocols for measuring arginase activity can further extend an understanding of the metabolic activity underlying macrophage polarization.