HL60 cells exhibiting a 140-fold increase in resistance to vincristine contain three surface membrane proteins with molecular weights of 210,000 (P210), 180,000 (P180), and 150,000 (P150) which are highly phosphorylated in vivo and in an in vitro system in the presence of Mn2+ and [gamma-32P]ATP. These phosphorylated proteins are either absent or present in very low levels in membranes of drug-...

Humanized M195 (HuM195) is a genetically engineered, human IgG1 version of the parent M195, a mouse immunoglobulin G2a, anti-CD33 monoclonal antibody which reacts with early myeloid progenitor cells and myelogenous leukemia cells. In Phase I studies in patients with relapsed and refractory myelogenous leukemia, HuM195 safely targeted to sites of disease and was nonimmunogenic. HuM195 shows only...

Human-mouse chimeric immunoglobulins G1 and G3 (IgG1 and IgG3) (ChG1, ChG3) and "complementarity-determining region"-grafted, humanized IgG1 and IgG3 (HuG1, HuG3) constructs of the mouse monoclonal antibody (mAb) M195 were characterized. M195 is a murine immunoglobulin G2a (IgG2a), anti-CD33 mAb, specifically reactive with acute myelogenous leukemia cells, that is active as an antileukemia agen...

BACKGROUND Werner syndrome (WS) results from defects in the RecQ helicase (WRN) and is characterized by premature aging and accelerated tumorigenesis. Contradictorily, WRN deficient human fibroblasts derived from WS patients show a characteristically slower cell proliferation rate, as do primary fibroblasts and human cancer cell lines with WRN depletion. Previous studies reported that WRN silen...

acute leukemia is characterized by the accumulation of neoplastic cells in the bone marrow and peripheral blood. currently, chemotherapy and differentiating agents have been used for the treatment of leukemia. recently, plant extracts, either alone or in combination with chemo agents, have been proposed to be used for the treatment of cancers. the aim of the present research was to study the cy...

Maturation of human myeloid cells is associated with quantitative and qualitative changes in protein kinase C (PKC) and increases in N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) receptors, actin, and actin regulatory proteins. We have studied the actin responses and cell shape changes caused by FMLP and its second messenger pathways in HL60 cells undergoing neutrophilic maturation. In u...

BACKGROUND Neutrophil activation induces citrullination of intracellular targets of anticitrullinated peptide antibodies (ACPA), which are specific for rheumatoid arthritis (RA). Citrullinated fibrinogen is bound by ACPA but it is less well understood how extracellular proteins are citrullinated. The cells that produce fibrinogen, hepatocytes, do not express peptidyl arginine deiminase (PAD) en...

We have developed a new test to differentiate between ping-pong and simultaneous mechanisms for tightly coupled anion exchange. This test requires the use of a dead-end reversible noncompetitive inhibitor. As an example, we have applied the test to the anion exchanger of the HL60 cell using the salicylic acid derivative 3,5-diiodosalicylic acid (DIS), which reversibly inhibits HL60 cell Cl/Cl e...

Human galectins have distinct and overlapping biological roles in immunological homeostasis. However, the underlying differences among galectins in glycan binding specificity regulating these functions are unclear. Galectin-8 (Gal-8), a tandem repeat galectin, has two distinct carbohydrate recognition domains (CRDs) that may cross-link cell surface counter receptors. Here we report that each Ga...