CD Classification of Human Lymphocyte Differentiation Antigens

Practice flashcards covering the CD classification of human lymphocyte differentiation antigens, including nomenclature, cell surface markers, malignancies, and clinical uses.

What is the Cluster of Differentiation (CD)?

A protocol used for the identification and investigation of cell surface molecules present on leukocytes.

What role do antibodies reacting with CD antigens play in immunology?

They are known to be one of the most essential tools for identifying leukocyte subpopulations.

What primary functions do CD molecules perform on immune cells?

They often act as receptors or ligands, play a role in cell signaling, and mediate cell adhesion.

How is a Cluster of Differentiation (CD) number assigned?

It is assigned to a group or cluster of monoclonal antibodies that recognize the same specific cell-surface protein or antigen.

Which laboratory techniques utilize combined CD markers to isolate specific cell populations?

Flow cytometry or immunohistochemistry.

Where was the CD nomenclature proposed and established?

In the first International Workshop and Conference on Human Leukocyte Differentiation Antigens.

How many CD unique clusters and subclusters have been identified?

More than 320.

What is required before a proposed surface molecule is assigned a CD number?

Two specific monoclonal antibodies (mAbs) must be shown to bind to the molecule.

What does the provisional designation "CDw" indicate?

Molecules recognized by just one monoclonal antibody, such as CDw168.

What do lowercase letters added after an assigned CD number signify?

They indicate larger molecules that share a common chain (e.g., CD1a, CD1b, CD1c, CD1d, or CD1e).

How is the presence or absence of a specific antigen denoted on a cell population?

It is denoted by a "+" for present or a "-" for absent (e.g., a "CD34+, CD31-" cell expresses CD34, but not CD31).

How is overall variability in CD expression marked in cell characterization?

It is marked as hi, mid, or low (alternatively bright, mid, or dim), such as CD62 low for effector memory T-cells.

Which CD markers define Stem cells?

CD34+, CD31-, and CD117.

Which CD marker is expressed on all leukocyte groups?

CD45+

What are the CD markers for Granulocytes?

CD45+, CD11b, CD15+, CD24+, CD114+, and CD182+.

What are the CD markers for Monocytes listed in the cell marker table?

CD4, CD45+, CD14+, CD114+, CD11a, CD11b, CD91+, and CD16+.

What CD markers define T lymphocytes?

CD45+ and CD3+.

What CD markers characterize T helper cells?

CD45+, CD3+, and CD4+.

Which CD markers and transcription factor characterize T regulatory cells?

CD4, CD25, and FOXP3.

What CD markers characterize Cytotoxic T cells?

CD45+, CD3+, and CD8+.

What CD markers identify B lymphocytes?

CD45+, CD19+, CD20+, CD24+, CD38, and CD22.

What CD markers identify Thrombocytes?

CD45+ and CD61+.

What CD markers characterize Natural killer cells?

CD16+, CD56+, CD3-, CD31, CD30, and CD38.

What cell type is identified by the Pan T cell marker CD3?

T cells (Pan T cell marker).

What cell types and malignancies are associated with CD5?

Immature T cells; T-cell-ALL; B cell chronic lymphocytic leukemia/ small lymphocytic lymphoma (CLL/SLL); Mantle cell lymphoma.

Which cell types and malignancies are associated with CD10?

Acute lymphoblastic leukemia: CALLA antigen of early precursor B- and pre-B cell ALL; Follicular lymphoma.

What cell types and disease are associated with CD11c?

Monocytes, Histiocytes, and hairy cell leukemia.

What cell types and malignancies express CD20?

Mature B cell marker except plasma cells; B cell lymphomas; Lymphocyte predominant Hodgkin lymphoma (lympho-histocytic Red-Sternberg cell variant, aka L&H cells, popcorn cells).

Which malignancy is associated with CD25?

Hairy cell leukemia.

Which CD markers are characteristic of Hodgkin lymphoma Classic Reed-Sternberg cells and Lacunar cells of nodular sclerosis type?

CD15 and CD30.

In which lymphoma are CD30-positive cells observed?

Anaplastic large cell lymphoma.

What cell types and disease are associated with CD33?

Myeloid progenitor cells and monocytes; acute myelogenous leukemia.

Which cell type and leukemia are associated with CD41?

Megakaryocytes; Acute megakaryocytic leukemia.

What is CD55, and what condition is associated with its loss?

Decay accelerating factor (DAF); loss is seen with paroxysmal nocturnal hemoglobinuria.

What are the five major uses of Cluster of Differentiation markers described in the lecture?

Cell Identification and Classification, Disease Diagnosis, Cell Signaling and Activation, Cell Adhesion, and Targeted Immunotherapy.