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What is Phagocytosis of TB bacilli does not occur because of - and explain in detail?
Virulent strains of tubercle bacilli form microscopic "serpentine cord" in which acid fast bacilli are arranged in parallel chains, cord formation is correlated with virulence. A "cord factor" has been extracted from virulent bacilli with petroleum ether. It inhibits migration of leukocytes, causes chronic granulomas, and can serve as an immunologic "adjuvant"