nonerythroid

Nonerythroid is a term used in hematology and histology to describe cells or tissues that are not part of the erythroid lineage, i.e., not derived from erythroblasts that mature into red blood cells. In adults, erythropoiesis occurs in the bone marrow alongside leukopoiesis and thrombopoiesis; nonerythroid cells encompass the myeloid and lymphoid lineages, including granulocytes, monocytes, macrophages, lymphocytes, dendritic cells, as well as megakaryocytes and platelets, and various stromal and support cells of the marrow.

In tissue samples and laboratory analyses, nonerythroid cells are often distinguished from erythroid cells by marker expression. Erythroid cells express markers such as glycophorin A (CD235a) and CD71, while nonerythroid cells lack these markers and express lineage-specific markers (for example CD3 on T cells, CD19 on B cells, CD14 on monocytes, CD11c on dendritic cells, and CD41 on platelets). This separation is commonly used in flow cytometry and morphologic examination to study distinct cell populations within blood and bone marrow.

Clinical relevance includes the use of the erythroid-to-nonerythroid ratio in bone marrow assessment. Alterations in this balance can reflect or contribute to disorders such as aplastic anemia (reduced overall hematopoiesis), myelodysplastic syndromes, leukemias, or other marrow failures. Understanding the nonerythroid compartment helps in diagnosing, monitoring, and researching hematologic diseases and the bone marrow microenvironment.

See also: erythroid lineage, hematopoiesis, myeloid cells, lymphoid cells.