"Selenoid (Crescent) Bodies" are known in hematology as Cuerpos en Media Luna in Spanish and Corps en demi-lune in French.
An original method of staining selenoid bodies and one which is suitable for morphologic structural studies has been described. The method is also suitable for staining stromas of erythrocytes.
Selenoid bodies originate from erythrocytes and correspond to their stromas. Selenoid bodies can be produced in vitro by the spreading of blood on a slide. Two factors influence their formation: a mechanical factor by friction of the erythrocytes against the surface of the slide and a chemical essential factor represented by the lipids of the blood, increasing the fragility of the erythrocytes.
The number of selenoid bodies in any smear of blood is directly proportional to its contents in lipids, either from an exogenous source (alimentary lipemia) or from an endogenous origin.
Selenoid bodies have also been found in the dog, sheep, rabbit, guinea pig, rat and hen.