The effect of Cd2+ on the respiration of rat liver mitochondria was investigated. The uncoupling effect of Cd2+ was partially restored by the addition of Mg2+. The influence of Cd2+ on adenine nucleotide concentrations in the reaction mixture consisting of mitochondria and ATP was also studied using high performance liquid chromatography. In the presence of added Mg2+, a two-fold increase in AM...

Cadmium (Cd2+) is a common toxic heavy metal ion. We investigated the roles of hydrogen sulfide (H2S) and cysteine (Cys) in plant responses to Cd2+ stress. The expression of H2S synthetic genes LCD and DES1 were induced by Cd2+ within 3 h, and endogenous H2S was then rapidly released. H2S promoted the expression of Cys synthesis-related genes SAT1 and OASA1, which led to endogenous Cys accumula...

γδ-T-Cell Receptor (TCR) lymphocytes were detected in mammary gland lavages collected from 10 clinically healthy virgin heifers before and after intramammary stimulation with synthetic muramyl dipeptide analogue. Using two-colour flow cytometry, CD2+ and CD2– subsets of γδ-TCR lymphocytes were analyzed. CD2+ γδ-TCR lymphocytes markedly prevailed over CD2– cells in intact mammary gland: 88.9 ± 4...

Cadmium (Cd2+) is a known carcinogen that inactivates the DNA mismatch repair (MMR) pathway. In this study, we have tested the effect of Cd2+ exposure on the enzymatic activity of the mismatch binding complex MSH2-MSH6. Our results indicate that Cd2+ is highly inhibitory to the ATP binding and hydrolysis activities of MSH2-MSH6, and less inhibitory to its DNA mismatch binding activity. The inhi...

The mechanism of Cd2+ block of Ca2+ currents (ICa) was explored in squid neurons using whole-cell patch clamp. Control currents activated sigmoidally, more rapidly at more positive potentials, and did not inactivate significantly. External Cd2+ up to 250 microM reduced ICa reversibly. For small depolarizations, the current for a step of 10 ms increased to a maintained value, resembling the cont...

Ligation of the CD2 co-stimulatory receptor on human T lymphocytes induces tyrosine phosphorylation and activation of the Tec-family tyrosine kinase, ITK. To examine whether any of several proline-rich (PR) stretches of the CD2 cytoplasmic tail are necessary for ITK activation we introduced wild-type and mutated versions of rat CD2, each missing at least one PR stretch of the tail, into human J...

Accessory cell surface molecules, such as T cell antigen CD2 and its ligand lymphocyte function-associated antigen 3 (LFA-3; CD58), are critical costimulatory pathways for optimal T cell activation in response to antigens. Interaction of CD2 with cell surface LFA-3 not only increases T cell/accessory cell adhesion, but also induces signal transduction events involved in the regulation of T cell...

To search for possible ligands of CD2 distinct from CD58 (lymphocyte function-associated antigen 3), we have produced a soluble pentameric CD2-immunoglobulin (Ig) fusion protein (spCD2) linking the 182-amino acid human CD2 extracellular segment with CH2-CH3-CH4 domains of human IgM heavy chain, thus enhancing the micromolar affinity of the CD2 monomer through multimeric interaction. Using quant...

A fter the demonstration almost 20 years ago that anti-bodies to CD2 are potent inhibitors of T cell function, this cell surface glycoprotein became one of the most intensively studied of all T cell antigens (1–3). The subsequent identification of LFA-3 (CD58) as a ligand for human CD2 led to the demonstration in cell culture experiments that the CD2–CD58 interaction dramatically enhanced T cel...