Antibody treatment of toxin poisoning--recent advances

The major responses to the administration of specific antibody or toxin-specific fragment are described. Toxin sequestration depends on the extent and rate of antibody distribution, the antibody affinity and its ability to form a non-active immune complex. Toxin redistribution is mainly influenced by the reversible binding and efflux kinetics of the toxin from the receptor. Finally, toxin elimination adopts the antibody elimination properties for low molecular weight compounds. These three basic mechanisms of the immuno-detoxification process could be optimized by designing the ideal antibody, in terms of size and origin, to inactivate the toxic properties. Calculation of the amount of infused antibody should be derived from the slope of the dose-effect curve rather than stoichiometrically.

Monoclonal antibody OPD4 is reactive with CD45RO, but differs from UCHL1 by the absence of monocyte reactivity

Monoclonal antibody OPD4 was described as a novel monoclonal antibody recognizing a helper/inducer T-cell subset in paraffin-tissue sections. The authors have analyzed this reagent with respect to its molecular weight, reactivity with leukocyte common antigen (LCA) transfectants and cell and tissue distribution. OPD4 was found to be reactive with the 180 kd molecular weight isoform of the leukocyte common antigen family, similar to antibody UCHL1 and therefore can be considered as a CD45RO reagent. The only difference in distribution was found to be the absence of OPD4 reactivity with peripheral blood monocytes. Since OPD4 recognizes the same antigen on T cells as UCHL1, both reagents do not need applied in the immunophenotyping of lymphomas.

A monoclonal antibody for terminal beta-galactose. Use in analysis of glycosphingolipids

A monoclonal antibody (mAb 8281) specific for the terminal beta-galactose (beta Gal) of glycosphingolipids (GSL) and glycoproteins was produced from mice immunized with lipid extract from fresh acute lymphocytic leukemia (ALL) cells. Immuno-thin layer chromatography (ITLC) and competition assays with purified neutral GSL standards, free sugars, and synthetic neoglycoproteins showed mAb 8281 to be strongly reactive with LacCer, GalCer and Gal-beta-O-(CH3)2S(CH3)2-CONH-(Gal-beta-O-CETE) linked to bovine serum albumin (BSA). The penultimate sugar also played a role in binding. The antibody was not reactive with carbohydrates with terminal alpha Gal structures and unrelated terminal moieties. Indirect immunoperoxidase staining and flow cytometry with mAb 8281 demonstrated positive staining on numerous tissues, including smooth muscle, gastrointestinal mucosa, lymph node B cells and monocytes. ITLC analysis of the GSL composition of fresh B cell neoplasms using mAb 8281 confirmed the presence of lactosylceramide and galactosylceramide in neoplasms of varying stages of differentiation. Because of its specificity for terminal beta Gal carbohydrate residues, mAb 8281 may be useful in structural and functional analyses of GSL.