The protooncogene product, Raf-1, is a serine/threonine kinase and has been implicated as an intermediate in signal transduction mechanisms. We examined neoplastic and normal B cells for phosphorylation and activation of Raf-1 protein in response to anti-immunoglobulin antibody (anti-Ig). Anti-Ig induced rapid phosphorylation of Raf-1 protein in both neoplastic B-cells of hairy cell leukemia an...

An increasing frequency of malignant lymphomas occurs among patients infected by human immunodeficiency virus. Because of the close similarities to human malignancies, we used a nonhuman primate model to study the pathogenesis of simian immunodeficiency virus (SIV)–associated malignancies. Specifically, we investigated (1) the presence of the SIV genome in tumor cells, (2) the presence of coinf...

B-lymphocyte development exhibits a characteristic order of immunoglobulin gene rearrangements. Previous work has led to the hypothesis that expression of the immunoglobulin mu heavy chain induces rearrangement activity at the kappa light-chain locus. To examine this issue in more detail, we isolated five matched pairs of mu- and endogenously rearranged mu+ cell lines from the Abelson murine le...

Multiple myeloma is an incurable malignancy, and there is currently no mouse model that fully recapitulates the development and progression of the disease. We now describe a transgenic mouse that expresses a Bcl-XL transgene under the control of the 3'kappa immunoglobulin light chain enhancer, which is most active in murine B cells in late developmental stages. These mice developed nonmalignant...

In order to improve the surveillance of serogroup B and C meningococcal diseases, enzyme-linked immunosorbent assays (ELISAs) specific for anti-B immunoglobulin M (IgM) and anti-C IgM and IgG antibodies were developed. The tests were evaluated by using paired sera from 122 patients with and 101 patients without laboratory evidence of meningococcal disease. Fifty-three of 67 patients (79%) with ...

Direct interaction between T-suppressor and dendritic cells (DCs) results in DC tolerance by inducing upregulation of immunoglobulin-like transcript (ILT) 3 and ILT4. DCs were treated with a lentiviral vector containing paired immunoglobulin-like B gene (PIR-B) DCs and the effect of PIR-B-DCs on graft-versus-host disease (GVHD) was analyzed after allogeneic bone marrow (BM) transplantation (BMT...

Two hundred and thirty strains of various gram-positive cocci were tested for quantitative, nonimmune binding of radiolabeled human polyclonal immunoglobulin G (IgG). The majority of coagulase-positive staphylococci and streptococci belonging to serogroups C and G showed a high uptake of IgG. The binding of immunoglobulin to group A streptococci was considerably less, with a number of strains c...

Introduction: Most B-cell malignancies are diagnosed based on morphologic and immunohistochemical criteria. Some cases, however, still present a challenge for the pathologist to discriminate between reactive hyperplasia and neoplastic disorders. Molecular techniques can be used as a helpful diagnostic tool in these cases. In this study, we assessed the value of polymerase chain reaction (PCR) t...