Kyuketsumadan

Kenichi and his uncle are miniaturized after receiving an injection of a substance called ZX, developed by the uncle. They travel inside the body of a young boy and reach his lungs, where tubercle bacilli are causing damage by creating a large cavity. The bacilli send Mode, a tubercle bacillus and daughter of Dr. Iyoa, to teach them human language. They form a bond with Mode, but conflict arises between the tubercle bacilli and the boy's immune cells. Kenichi and his uncle become entangled in the ensuing battle.