Cells at Work!

is a Japanese manga series written and illustrated by Akane Shimizu. It began its serialization in the manga magazine Monthly Shōnen Sirius in March 2015. Kodansha Comics has licensed it for English release. An anime adaptation by David Production premiered on July 7, 2018.

A spin-off manga, by Haruyuki Yoshida began serialization in Kodansha's Nakayoshi in May of 2017. Another spin-off manga, by Moe Sugimoto and supervised by the original author, began serialization in Monthly Shōnen Sirius in September of 2017. A third spin-ff manga, by written by Shigemitsu Harada with art by Issei Hatsuyoshi, began serialization in Kodansha's Morning in 2018.

Plot
Strep throat! Hay fever! Influenza! The world is a dangerous place for an anthropomorphized red blood cell just trying to get her deliveries finished. Fortunately, she’s not alone... she’s got a whole human body’s worth of cells ready to help out! The mysterious white blood cell, the buff and brash killer T cell, the nerdy neuron, even the cute little platelets—everyone’s got to come together if they want to keep you healthy!

Official

 * Official anime site (Japanese)
 * Official English site

Other Sources

 * Wikipedia
 * (anime)
 * (manga)