B lymphocyte markers in multiple myeloma and related plasma cell dyscrasias.

Multiple myeloma and benign monoclonal gammopathies are regarded as monoclonal B cell proliferations in which B lymphocyte maturation is blocked in the final stages of the differentiation cycle. "Blocked" cells accumulate in the body and produce large quantities of immunoglobulins. These are monoclonal, because they come from a monoclonal cell stock.

Relationships between cell-cell interactions, cAMP, and gene expression in a developmental mutant of Dictyostelium discoideum.

Previous work has led us to propose that close cell-cell associations during D. discoideum development serve as a signal to deactivate expression of discoidin I mRNA, and that intracellular cAMP serves as a mediator of this regulatory pathway. This model is based in part on the failure of a morphogenetic mutant, EB-21, to deactivate discoidin I expression under conditions where these cells fail to acquire cell-cell cohesiveness and hence remain as single cells, unlike the wild type strain which forms multicellular aggregates.

Distinct developmental regulation and properties of the responsiveness of different genes to cyclic AMP in Dictyostelium discoideum.

Cyclic AMP (cAMP) is known to be an important mediator of gene expression in eukaryotic cells. At present, little is known about the developmental events which render specific genes responsive to cAMP in distinct cell types, or about the biochemical mechanisms by which cAMP exerts these regulatory effects. By examining the effects of cAMP treatment on specific mRNA levels in Dictyostelium discoideum cells with different 'developmental histories', we defined the developmental states in which specific genes display responsiveness to cAMP.

Immunological studies on the origin of the precursor cells in Waldenström's macroglobulinemia.

Preliminary results obtained with OK anti-T and FMC anti-B monoclonal antibodies in a study of peripheral blood lymphocytes from eight patients with Waldenström's macroglobulinemia and of bone marrow lymphocytes from three patients, are reported. Endocytoplasmic immunofluorescence revealed a 1 to 3% marrow plasma cell fraction in all three cases, together with an approximately 10% increase in the monoclonal precursor compartment. Displacement of the peripheral blood helper: suppressor ratio was also observed using anti-T-lymphocyte monoclonal antibodies.

Regulation of discoidin I gene expression in dictyostelium discoideum by cell-cell contact and cAMP.

We have previously presented evidence that cell-cell contact is the normal developmental signal to deactivate discoidin I gene expression in D discoideum [Berger EA, Clark JM: Proc Natl Acad Sci USA 80:4983, 1983]. Here we provide genetic evidence to support this hypothesis by examining gene expression in a cohesion-defective mutant, strain EB-21, which enters the developmental program but is blocked at the loose mound stage. When this strain was developed in suspension, the cells remained almost entirely as single amoebae, unlike the wild type, which formed large multicellular aggregates.

Normalization of electrophoretic mobility of lymphocytes in patients with primary immunoglobulin deficiency treated with intravenous immunoglobulins.

The behaviour of lymphocyte sub-populations and lymphocyte electrophoretic mobility has been studied in seven patients with agamma/hypogammaglobulinaemia before and after gammaglobulin therapy.

[Immunology of non-Hodgkin lymphomas].

Cytological and kinetic immunological homogeneity is typical of such lymphomas. Their cytogenesis is broadly connected to the development and differentiation of lymphocytes. It is mainly a question of proliferating B lymphocytes of which the monoclonal membrane receptors are tumoral markers.