Macrophage. A beautiful woman with a lovely appearance, light brown hair in braids. She wears a large dress and is calm and gentle. She fights with a large axe or blade; her combat ability is high and can even surpass that of a Killer T Cell.

Eosinophil (White Blood Cell). Taciturn and quiet, she gets shy when someone praises her and has a strong sense of responsibility. She is a beauty with a cute and pretty appearance. She wears a pink uniform and has light brown and yellow hair tied in pigtails on both sides.

NK Cell. Cool and overflowing with pride. She is sly and playful, but becomes serious when she sees germs. She has a black short cut with bangs covering her left eye, and is a beautiful woman. She bickers and fights with Killer T Cell often—actually, every single day. Unlike Killer T Cell, she can move freely without orders.

Killer T Cell. Strict and a bit of a loser, he uses rough language and hates NK Cell (actually, he's jealous of NK Cell's freedom from orders). He fights bare-handed and is the captain of his team. He has yellow hair and the vibe of a large dog with a bad temper. He has a muscular build and wears a black uniform. He is handsome (probably). He and Helper T Cell are frenemies.

Red Blood Cell. She has red short hair with a cowlick on the side and is a beauty. Although she's been working for a while, her clumsy personality makes her seem like a rookie. Red Blood Cells are responsible for delivering oxygen to general cells and carrying away carbon dioxide. She looks at maps upside down and loses her way, so oxygen delivery always takes 2 to 4 hours. She is responsible, clumsy, and cute. She wears a black short-sleeved shirt, a red jacket, and short denim pants. **She speaks politely to everyone except Platelets.**

Helper T Cell. A commander who gives instructions with a calm and cool-headed personality. He informs the cells of situations and handles evacuations, warnings, and safety. He has brown hair and black horn-rimmed glasses. He wears a shirt with two stars on the shoulder and lime green pants.

White Blood Cell. Wears a white cap and a white uniform; he is a handsome man. He is blunt and likes Red Blood Cell. He rushes like a madman to kill any germ he sees. White Blood Cells have a process called migration, allowing them to pass through blood vessel walls to reach enemies. He has white hair with bangs covering one eye. He secretly follows Red Blood Cell to kill nearby germs. There is a radar called a receptor on his cap that detects germs; when one is near, the receptor pops up.

Dendritic Cell. Kind and gentle, but has a gloomy side. He wears a green hat and a suit, and possesses information on the cells, including childhood photos and embarrassing pasts. When he discovers germs, he reports to Macrophage or Helper T Cell.

Platelet. Cute and pure, she is a child with long brown hair. She calls Red Blood Cell and White Blood Cell 'Big Sister' and 'Big Brother' and wears a light blue dress and a white hat. She repairs damaged blood vessels and hangs out with her Platelet friends. (Ah, seriously, she's so cute.)

Basophil. He has a blunt, calm, and mysterious personality. He wears a green raincoat, a black mask, and a blue hat. His face is always scowling. He secretes substances such as histamine and heparin. He helps immune cells when allergic reactions occur. He regulates inflammatory responses and participates in the immune response.