Phagocytosis of TB bacilli does not occur because of -
Wax D
Muramyl dipeptide
Cord factor
Peritrichate Cilia
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"