Concanavalin isolation

Figure 1 Continued on next page) Immunopotentiating reconstituted influenza virosomes (IRIV) induced antigen specific proliferation of CD4+CD45RO+ cells. (A) Peripheral blood mononuclear cells (PBMQ from healthy donors n=3) were cultured in the absence of stimuli (Neg), in the presence of IRIV (V), and in the presence of control liposomes (L) at the indicated dilutions. Proliferation was measured on day 6 of culture by H-thymidine incorporation. (B) Cord blood mononuclear cells from two donors were cultured in the absence of stimuli (Neg) or in the presence of phytohaemag-glutinin (PHA), concanavalin A (ConA), IRIV (V) or L at the indicated concentrations. Proliferation was measured on day 3 of culture for PHA and ConA cultures and on day 6 for IRIV and L stimulated cultures. (Q Purified CD4+ or CD8+ cells were cocultured with autologous irradiated PBMC in the absence of stimuli (Neg) and in the presence of IRIV (V) at the indicated concentrations. Proliferation was measured on day 6 of culture by H-thymidine incorporation. (D) Purified CD4/CD45RA+ cells and CD4/CD45RO-I-cells were isolated from PBMC of one healthy donor and cocultured with autologous irradiated PBMC in the presence of IRIV (V) or L at the indicated concentration. Proliferation was measured on day 6 of culture by H-thymidine incorporation. Source From Ref 6.

The 48-h concanavalin A-induced lymphoblastogenic responses in splenocytes isolated from BALB/c mice treated with Corynebacterium parvum and 1,1-dimethylhydrazine mice were significantly increased in comparison with C. parvum treatment alone (Frazier et al., 1992), indicating that 1,1-dimethylhydrazine can overcome certain types of immunosuppression. 

Keenan, T. W., Franke, W. W. and Kartenbeck, J. 1974A. Concanavalin A binding by isolated plasma membranes and endomembranes from liver and mammary gland. Febs. Lett. 44, 274-278. 

Concanavalin A is an antibody-like protein isolated from the jack bean. 82 It was shown to form a precipitate with glycogen and with yeast mannan, and was later also used to differentiate between glycogen-like polysaccharides from various sources.283 284 It has now been shown that concanavalin A forms a precipitate only with branched polysaccharides which contain terminal, nonreducing a-D-glucopyranosyl or a-D-manno-pyranosyl groups.18 The combining sites of the protein appear to be directed against the 2-deoxy-a-D-aratano-hexopyranosyl system.2 ... 

Stirpe, F., Olsnes, S., and Pihl, A. (1980) Gelonin, a new inhibitor of protein synthesis, nontoxic to intact cells. Isolation, characterization, and preparation of cytotoxic complexes with concanavalin A. J. Biol. Chem. 255, 6947—6953. 

The proteins from the jack bean (Canavala ensiformis) were first studied over 60 years ago by Jones and Johns(6). Several years later, Sumner(7), while studying urease (also from the jack bean), isolated three other proteins, two of which could be crystallized, concanavalin A and B. It should be noted that this report of crystalline Con A by Sumner appeared about seven years before he reported the first crystallization of an enzyme, urease(8). 

Solanidine-GTase was purified to near homogeneity from potato sprouts. The isolation of this enzyme was complicated by its copurification with patatin. Separation of the two proteins was finally achieved by binding the glycosylated patatin to concanavalin A, under conditions where the solanidine-GTase did not bind. In this study, no enzyme activity was detected... 

The plant lectin concanavalin A, a metalloprotein isolated from the jack bean, has also received considerable attention. (588-590,630,631) Using the stopped flow NMR technique three distinct conformation states of the protein, when it is bound to Mn, Ca, and a-methyl-D-mannoside, (630) have been deduced. 

Allan, Auger and Crumpton used Con A-Sepharose to isolate glycoprotein cell surface receptors for concanavalin A from pig lymphocyte membranes solubilized with sodium deoxycholate [134]. 

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