Lymphoblast

It occurs when the lymphocyte is activated by an antigen and increased in volume by nucleus and cytoplasm growth as well as new mRNA and protein synthesis.

[1] Lymphoblasts can also refer to immature cells which typically differentiate to form mature lymphocytes.

[3] Although commonly lymphoblast refers to a precursor cell in the maturation of leukocytes, the usage of this term is sometimes inconsistent.

Lymphoblasts can be distinguished microscopically from myeloblasts by having less distinct nucleoli, more condensed chromatin, and an absence of cytoplasmic granules.

However these morphologic distinctions are not absolute and a definitive diagnosis relies on antibody immunostaining for the presence of unique cluster of differentiation receptors.