Understanding Acute and Chronic Inflammation

Inflammation is a complex biological response to harmful stimuli, such as pathogens, damaged cells, or irritants. It is a protective mechanism involving immune cells, blood vessels, and molecular mediators.

Triggers of Inflammation

• Infections (bacterial, viral, fungal)
• Physical trauma
• Chemical irritants
• Autoimmune reactions

Vascular Changes in Inflammation

Key vascular responses include:

• Vasodilation – Increased blood flow to affected tissue
• Increased permeability – Facilitates immune cell migration
• Endothelial activation – Promotes adhesion of leukocytes

Cellular Responses in Acute and Chronic Inflammation

Inflammation involves various cell types:

Acute Inflammation

• Neutrophils – First responders to infection
• Mast cells – Release histamine for vasodilation

Chronic Inflammation

• Macrophages – Engulf pathogens and stimulate tissue repair
• Lymphocytes – Play a role in immune memory and sustained inflammation

Mediators of Inflammation

Chemical mediators regulate inflammatory processes:

• Cytokines – Interleukins (IL-1, IL-6), tumor necrosis factor (TNF-alpha)
• Chemokines – Guide immune cells to the site of inflammation
• Lipid-derived mediators – Prostaglandins and leukotrienes modulate inflammatory response

Conclusion

Inflammation is essential for healing but can be detrimental if unchecked. Chronic inflammation is implicated in various diseases, including arthritis, cardiovascular diseases, and cancer.