We have used bovine serum albumin in the preparation of peripheral blood smears and compared the morphology of leukocytes with smears prepared routinely without albumin. The albumin slides were prepared from a mixture of one drop of 22% albumin and 5 drops of EDTA-collected peripheral. Parallel evaluation of smears with and without albumin was performed on 72 cases of lymphoproliferative disorders, including chronic lymphocytic leukemia (nϭ38), chronic lymphocytic leukemia/prolymphocytic leukemia (nϭ9), splenic marginal zone lymphoma (nϭ7), chronic lymphocytic leukemia with Ritcher's transformation (nϭ6), mantle cell lymphoma (nϭ5), T cell prolymphocytic leukemia (nϭ3), large cell lymphoma (nϭ3), follicular lymphoma (nϭ1). Lymphoid cells were counted on each preparation and divided into four types of cells: small (10-15 micron), medium (15-20 micron), large (Ͼ20 micron), and smudged cells. The percentages of the four subtypes of cells on each preparation were compared. As shown in table 1, there were significant differences between the two preparations in each subtype of cells. As expected, the most conspicuous difference was in the number of smudged cells (table 1). Significant reduction in smudged cells was noted on the albumin preparation. Most importantly, the data suggests that there was a proportional decrease in smudged cells whether cells are considered small, medium, or large. Therefore the albumin preparation does not influence the relative ratio of cells in the four categories.In addition to marked decrease in smudge cells, we observed that in majority of patients with splenic marginal zone lymphoma, some of the lymphoid cells on the albumin preparation show marked irregularity in the nuclear contour and become floret shaped (See figure 1). This exaggeration of the folding and irregularity of nuclear contour was not conspicuous in other forms of chronic lymphoproliferative diseases. While the number of splenic marginal zone lymphoma examined here is small, this observation can be helpful and when observed additional diagnostic tests should be used to confirm or rule out the diagnosis of splenic marginal zone lymphoma.

Because the administration of hematopoietic growth factors and the use of stem cell support often fails to alleviate the neutropenic phase induced by cytotoxic drugs, several investigators have attempted to expand ex vivo hematopoietic progenitors for clinical use. These attempts have clearly shown that the cultured cells are functional and can be safely administered to patients, but that the in vivo performance is disappointing and the concept as a whole is not yet clinically useful. The major reasons for these unsuccessful attempts are thought to be cumbersome cell fractionation techniques, contamination, prolonged incubation, and the use of less than ideal cytokine combinations. In response, we have developed a simple procedure for ex vivo expansion of myeloid progenitor cells. In this assay, unfractionated mononuclear cells from apheresis donors are incubated in nonpyrogenic plastic bags for 7 days in the presence of culture medium either containing fetal calf serum or human plasma, granulocyte colony-stimulating factor, and stem cell factor. We have demonstrated that under these conditions the number of colony-forming units (CFU) granulocyte-macrophage (CFU-GM) and of CFU-granulocyte-macrophage-erythroid-megakaryocyte (CFU-GEMM) increased 7- and 9-fold, respectively, by day 7 and the number of burst-forming units-erythroid (BFU-E) increased 2.7-fold by day 5 of culture. Significant increases in the numbers of cells expressing CD34+, CD34+/CD38+, CD34+/CD33+, CD34+/CD15+, and CD34+/CD90+ and significant declines in the numbers of cells expressing CD34+/CD38- and CD19 surface antigens were also observed. The relative numbers of cells expressing T-cell markers and CD56 surface antigen did not change. By using different concentrations of various hematopoietic growth factor combinations, we can increase the number of mature and immature cells of different hematopoietic lineages.

We report four cases of a "T-cell-rich B-cell chronic lymphoproliferative disorder" involving the bone marrow and not extramedullary sites. The neoplastic B-cell proliferation in these cases was composed predominantly of small lymphoid cells with features of both hairy cell leukemia and lymphoplasmacytoid lymphoma. All cases presented with neutropenia and with difficulty in diagnosis. We present the clinical, morphologic, cytochemical, and immunophenotypic findings in these cases and discuss this entity.