A 55-year-old male with a history of hypertension, obesity, and chronic kidney disease presents with sudden-onset severe pain, redness, and swelling in his right first metatarsophalangeal (MTP) joint. He states that the pain started overnight and is excruciating. Joint aspiration reveals negatively birefringent needle-shaped crystals under polarized light microscopy. Which of the following is the primary inflammatory mediator responsible for the acute gout flare in this patient?
