Hataraku Saibou!!

Synopsis

Normal Cell is rescued by the Neutrophils, but they start getting overwhelmed by the bacteria until the lactic acid bacterium returns with its brethren and they turn the tide. With the bacteria defeated, the toxic gas dissipates. Memory T Cell uses his ultimate technique, the T Cell Perforin Cannon Punch. Although it was a made up technique taught to him as a joke, it actually works, firing a beam from his fist that damages Cancer Cell enough that Regulatory T Cell finally recognizes him as an enemy and turns against him. Cancer Cell continues to fight, but without the carcinogens in the toxic gas, he weakens. U-1146 escapes the pod and slays him, with Cancer Cell calling him his friend as he dies. As the lactic acid bacteria repair the damage, U-1146 calls Normal Cell a hero for bringing them. Memory T Cell tries to teach the Naive T Cells the T Cell Perforin Cannon Punch, but cannot replicate what he did. AE3083 catches up with U-1146 before they return to their regular routine.

(Source: Wikipedia)