Flow Cytometry Sample Types
Yes, flow cytometry is routinely performed on blood samples, including both peripheral blood and bone marrow aspirates, and represents a standard specimen type for this analytical technique. 1, 2
Primary Sample Types for Flow Cytometry
Flow cytometry is performed on multiple specimen types in clinical practice:
Peripheral blood (whole blood) is a standard and frequently used specimen for flow cytometry analysis, particularly for immunophenotyping lymphocytes, detecting circulating tumor cells, and monitoring CD4+ T-cell counts. 1
Bone marrow aspirates are the preferred specimen for diagnosing and monitoring hematological malignancies, especially plasma cell disorders like multiple myeloma, where bone marrow contains the primary disease burden. 1, 2
Lymph node and tissue specimens can be processed into single-cell suspensions for flow cytometric analysis, though this requires mechanical or enzymatic dissociation to create suspended cells suitable for analysis. 3, 4
Technical Considerations for Blood Specimens
The preparation method depends on the specimen type:
Whole blood/marrow approaches using fixative-free erythrocyte lysis are the consensus-recommended methods for plasma cell enumeration and phenotyping, as they preserve cell populations without significant bias. 1
First-pull aspirate samples are recommended for optimal bone marrow analysis, as sample quality directly impacts the concordance between flow cytometry and morphological assessment. 5
Density gradient centrifugation is inappropriate for cell enumeration because it can variably increase or decrease the percentage of target cells compared to whole blood methods, though it may be suitable for specific applications like cell culture. 1
Clinical Applications in Blood Samples
Flow cytometry on blood specimens enables:
Rapid diagnosis and monitoring of acute leukemias and chronic lymphoproliferative disorders through multiparametric analysis of circulating cells. 2, 6
Detection of minimal residual disease in peripheral blood, though bone marrow remains the primary site for assessing disease burden in plasma cell disorders. 2, 5
CD4+ T-cell monitoring in HIV-infected patients using standardized single-platform absolute counts with whole blood specimens. 1
Important Caveats
Peripheral blood may not reflect bone marrow disease burden in plasma cell disorders, as these conditions primarily involve the bone marrow compartment, and circulating plasma cells may be minimal or absent even with significant marrow involvement. 2, 5
Flow cytometry requires suspended cells for analysis, which distinguishes it from immunocytology that can evaluate cells on slides while preserving architectural relationships and cytomorphological features. 1
The technique measures cell surface and intracellular antigens, size, and granularity on individual cells flowing in single file, but cannot assess tissue architecture or spatial relationships that may be critical for certain diagnoses. 3, 6