Rapid immunotyping of B-cell non-Hodgkin's lymphomas by flow cytometry. A comparison with the standard frozen-section method

The authors compared immunotyping (IT) results obtained by both standard frozen section (FS) and flow cytometry (FC) methods on 218 biopsies suggestive of lymphoma to learn the advantages of each method. The independent interpretations of the FS and FC IT results were concordant in 93% (202 of 218) of cases. The 16 cases with discordance were reviewed and seven causes for discrepancy found: methodologic problems, focal lymphomatous involvement, more sensitive light chain detection by FC, inadequate sample for FC, interpretation error, sample mislabeling for FC, and unexplained. Eleven of the concordant B-cell non-Hodgkin's lymphomas (NHLs) studied by FC did not have a kappa:lambda ratio of 3 or greater or 0.5 or less and were shown to express light chain restriction by a D-value of 15 or greater with the use of statistical analysis of the kappa and lambda histograms or by multiparameter analysis of large versus small cells. The authors found both methods to be effective for phenotyping lymphomas, however, each has distinct features, making them complementary in their applications.

Alpha interferon: progress and perspectives in the biotherapy of chronic myelogenous leukemia

Chronic myelogenous leukemia is a myeloproliferative disorder representing 20%-30% of all leukemias. The disease is characterized by a cytogenetic abnormality called the Philadelphia chromosome. Except in patients who have undergone bone marrow transplantation (BMT), the natural history of chronic myelogenous leukemia has not changed in the last 30 years. Recombinant interferon alpha controls thrombocytosis and leukocytosis, reduces the leukemic infiltrate in the bone marrow, returns the spleen size to normal, and converts some patients to a normal chromosome pattern. This review summarizes the clinical and cytogenetic responses to date. The most significant observation is that, aside from treatment with BMT, interferon is the only agent that induces cytogenetic remissions.

Primary central nervous system lymphoma as a variant of Richter's syndrome in two patients with chronic lymphocytic leukemia

Primary parenchymal central nervous system (CNS) non-Hodgkin's lymphoma subsequently developed in two patients with chronic lymphocytic leukemia (CLL). These two patients represent what we believe to be the first examples of Richter's syndrome due to primary brain lymphoma. Neither evidence for systemic lymphoma nor of progression of the leukemia was found. We believe that the description of these two cases expands the clinical spectrum in which Richter's syndrome may occur. In patients with CLL, careful attention must be given to neurologic symptoms, particularly those that develop abruptly. Primary CNS lymphoma must enter into the differential diagnosis when a cerebral mass lesion is found in such patients by the appropriate neuro-imaging.

Rapid S-phase determination of non-Hodgkin's lymphomas with the use of an immunofluorescence bromodeoxyuridine labeling index procedure

Cell kinetic measurements are currently being investigated to determine if they are useful in the clinical management of patients with non-Hodgkin's lymphomas (NHLs). Although the tritiated thymidine labeling index (TLI) is the standard method of S-phase measurement, it is difficult to perform. The authors describe a slide-based immunofluorescence labeling index (LI) method that uses 5-bromo-2-deoxyuridine (BrdUrd) as the pulsing medium and a monoclonal antibody (BU-1) to BrdUrd. The BrdUrd LI was performed on 217 NHLs and compared with routine histologic results. The authors found a median BrdUrd LI of 0.9% for low-grade NHLs; 7.5% for intermediate-grade; 10.4% for high-grade; and 2.2% for T-cell NHLs. This method provides a rapid, reliable S-phase measurement that can be easily performed in the clinical laboratory. It should replace the TLI and allow wider application of S-phase measurements in the NHL.

Immunofluorescence labeling indices in myeloma and related monoclonal gammopathies

We measured plasma cell labeling indices (LI) in 52 patients with monoclonal gammopathies. Cytoplasmic reactivity with polyspecific or kappa- and lambda-specific light chain anti-Ig reagents identified monoclonal plasma cells, plasmablasts, and lymphocytoid plasma cells. Among newly diagnosed untreated patients, a high immunofluorescence LI distinguished those with multiple myeloma (MM) from those with stable monoclonal gammopathies (P less than 0.002). Among treated patients with MM, those in the plateau phase of the disease had low LI, whereas patients in the relapse phase or early in treatment had high LI. The immunofluorescence LI correctly classified three more patients with newly diagnosed MM than did the tritiated thymidine LI technique. LI specific for the neoplastic plasma cells resulted in excellent discrimination of patients with active disease. Because results are easily and rapidly obtained, this technique is useful clinically.

Evaluation of the Coulter Counter model S-Plus IV

Evaluation of linearity, carry-over, precision, and accuracy of a Coulter Counter model S-Plus IV prototype showed that they meet the manufacturer's specifications. The instrument also was compared with an earlier model. Correlations of the lymphocyte and granulocyte values in the three-part differential count with manual eye-count and a Technicon Hemalog D90 results were very close to the correlation of eye-count to Hemalog D90 results. The percentage of mononuclear cells showed acceptable correlation to the manual eye-count when monocytes were combined with blasts, eosinophils, and basophils. The medical effectiveness of the three-part differential was determined by comparison with manual eye-counts in 1,084 samples. The false positive and false negative values were 7.38% and 7.84%, respectively. The instrument has acceptable limits of operation. When combined with analysis of histograms by trained personnel, the three-part differential count is capable of screening for abnormalities that require further analysis.

Localization of eosinophil granule major basic protein in human basophils

In experiments using an immunofluorescent method to localize human eosinophil granule major basic protein (MBP) in cells and tissues, a small number of cells stained for MBP that subsequently could not be identified as eosinophils. Because the Charcot-Leyden crystal protein, another eosinophil protein, was recently identified in basophils, we tested whether MBP might also be a constituent of blood basophils. Highly purified, eosinophil-free basophil suspensions were prepared using the fluorescence-activated cell sorter (FACS) to sort basophil-containing mononuclear cell preparations stained with fluorescein-conjugated sheep IgG anti-human IgE antibody. Using these FACS-purified basophils, we found that: (a) enrichment for surface IgE-positive cells (greater than 95% basophils) by FACS also enriched for cells staining for MBP by immunofluorescence; (b) MBP appeared to be localized in the histamine-, heparin-containing granules; (c) significant quantities of MBP were measurable by radioimmunoassay (RIA) in freeze-thaw detergent extracts of purified basophils; and (d) RIA dose-response curves for extracts of purified eosinophils and basophils had identical slopes. The MBP content of basophils from normal individuals averaged 140 ng/10(6) cells, whereas purified eosinophils from normal donors and patients with the hyper-eosinophilic syndrome averaged 4,979 and 824 ng/10(6) cells, respectively. MBP was also detected by immunofluorescence and RIA in cells obtained from a patient with basophil leukemia, although the MBP content for basophil leukemia cells was lower than that for normal basophils. We conclude that basophils contain a protein that is immunochemically indistinguishable from eosinophil granule MBP.