Monoclonal antibody OPD4 was described as a novel monoclonal antibody recognizing a helper/inducer T-cell subset in paraffin-tissue sections. The authors have analyzed this reagent with respect to its molecular weight, reactivity with leukocyte common antigen (LCA) transfectants and cell and tissue distribution. OPD4 was found to be reactive with the 180 kd molecular weight isoform of the leukocyte common antigen family, similar to antibody UCHL1 and therefore can be considered as a CD45RO reagent. The only difference in distribution was found to be the absence of OPD4 reactivity...

MT3 is a new antibody reactive with a restricted isoform of the leukocyte common Ag (CD45) family. The Ag is mainly expressed on T lymphocytes and thymocytes. It is differentially expressed on B cell subpopulations, with no staining of the majority of small follicular mantle zone B cells but positive staining of the majority of marginal zone B cells of spleen. Like most CD45 antibodies, reactivity can be demonstrated in fresh frozen as well as in formalin-fixed, paraffin-embedded tissues. This reactivity clearly differs from all other published anti-CD45...

A panel of monoclonal antibodies, specific for either protein or carbohydrate components of the leukocyte common antigen (LCA), were used to characterize the expression pattern of different variants of this antigen complex. Immunohistochemical and flow cytometric analysis was carried out on human lymphoid tissues from different anatomical compartments. We found that variations in terminal sialic acid or 0-linked sugar moieties were associated with drastic differences in reactivity with some of the CD45R antibodies. For example, the carbohydrate determinants recognized by MT2 (CD45RA) and 2B11 (CD45) were not or...

We undertook a study to determine the specificity of the monoclonal antibody, B-ly-7, for hairy cell leukemia (HCL) by examining the expression in 150 samples from B-cell lymphoproliferative diseases as well as screening for reactivity in a number of other hematologic malignancies. Within the B-cell lineage we found that the expression of B-ly-7 was highly specific for HCL and reacted with all 28 cases examined, as well as with 3 of 9 cases of a variant form of HCL. Cells of other closely related B-cell disorders, prolymphocytic leukemia,...