Quantitative analysis of leukocyte membrane antigen expression: Normal adult values

Abstract

In this paper the normal ranges of the expression of various differentiation antigens, referred to by their cluster of differentiation (CD) numbers, are described on the lymphoid, monocytic, and polymorphonuclear (PMN) blood populations in normal healthy individuals. The values expressed as antibody binding capacity per cell (ABC/cell) are related to the density of antigenic molecules expressed by these cells. These values have been quantitated by the quantitative indirect immunofluorescence (QIFI) test which renders the ABC/cell values for the different antigens directly comparable and defines a “league table,” i.e., an enumeration of antigen expression on the three main cell types studied. The values for occasional antigen that are expressed differently in adults and the elderly or men and women (CD5, CD8, and CD18) are also shown. Furthermore, the QIFI test is used in two‐color immunofluorescence for defining the subset heterogeneity within the T lineage for the CD2 and CD7 antigens within the separately analyzed CD45RA and CD45RO subsets. These quantitative immune phenotype analyses, also referred to as quantimetry, show variations in ABC values if different monoclonal antibodies (MAbs) are used, although these differences are frequently minor. Therefore, using whole blood and well‐characterized MAbs, we established values of antigen density in normal adults which can be regarded as control values for the various pathological conditions where CD antigen expression may be altered. © 1996 Wiley‐Liss, Inc.

Influence of colloid fluids on polymorphonuclear granulocyte function in vivo

“…Thus, the minor variations observed in in vitro experiments may display changes due to sample preparation and contact of blood with the foreign surfaces of culture tubes. Such unspecific activation has previously been reported in several studies (10–12). Another explanation could be that in vivo granulocytes with upregulated adhesion molecules on their surface would have an increased tendency of leaving the blood and migrating into the tissues.…”

A sensitivity scale for targeting T cells with chimeric antigen receptors (CARs) and bispecific T-cell Engagers (BiTEs)

“…However, for the well-studied epitopes CD19 and CD20, which are expressed by both normal and malignant C cells, several measurements exist. In normal B cell, CD19, which is clinically targeted by both CAR-expressing and BiTE-treated T cells, 24 , 47 has been reported to be at levels of ~20,000–30,000 epitopes per cell, while CD20 has been reported to be at ~40,000–160,000 epitopes per cell 48 - 51 . Interestingly, in B-cell neoplasms, the levels of both epitopes are often lower: CD19 has been reported at ~5,400–13,300/cell and CD20 at ~10,500–30,500/cell 51 .…”

From research tool to routine test: CD38 monitoring in HIV patients

“…It is important to emphasize that the current QC procedures for CD4+ lymphocyte enumeration, such as those implemented for the PLG test, are for assessing precision and accuracy of absolute cell counting procedures (20). As the CD38/CD8 cell activation assay does not report the absolute CD38 counts, the focus of a CD38 QC is primarily concerned with mean fluorescence intensity measurements (CD38 MFI) and this is achieved by ensuring stable instrument settings and quantitative FC (QIFI) (12) for stabilized cellular immuno‐fluorescence assays (SCIFA) (13).…”

“…An additional quantitative FCM step can be applied to express these results as mean numbers of molecules on the surface of CD8 + T lymphocytes. This latter step utilizes carefully standardized research protocols (3, 4, 7, 11) or commercially available kits including the QIFI (12), CellQuant (13), and the QuantiBRITE™ technologies (14) where calibrated bead standards convert the logarithmic CD38 MFI values to a linearized scale for the number of CD38 molecules per cell (3, 11–16). However, these linearized scales can also be made using biological standards, e.g.…”