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The analysis of antigen E of ragweed pollen by polyacrylamide gel electrophoresis in sodium dodecyl sulfate (SDS) resulted in the demonstration of two subunits of molecular weights of about 20 000 and 14 500. These results confirm earlier studies on antigen E by gel chromatography that demonstrated a two-polypeptide subunit composition. Treatment of antigen E with 1% SDS (in the absence of reducing agent) resulted in the dissociation of the two polypeptide chains, which indicates that the bonds bridging the subunits are non-covalent in nature.

GRIFFITIIS, B. W., ~m BRUNET, R. Isolation of a basic protein antigen of low ragweed pollen, Can.J. Biochem. 49,596400 (1976).A fractionation method has been developed for the preparation of a basic protein antigen @PA-R) from ragweed pollen. This antigen possesses potent allergenic activity. It is homogeneous by gel filtration on Sephadex 6-188 and carboxymethyl-Sephadex chromatography. By the former technique the molecular weight of the BPA-R was estimated to be 28 886. Judged by its physicochemical and immunologic P roperties the BPA-R appears to be distinct from several other highly purified antigens currently isolated rssm ragweed pollen.The BPA-R and AgE (a highly purified acidic protein antigen) when tested together in Ouchterlony analysis displayed reactions of typical partial imumological identity with rabbit anti-ragweed sera which were produced by hyperimmunization utilizing complete Freund's adjuvant. In contrast rabbit antisera, produced on a shorter schedule with BPA-R (using incomplete Freund's adjuvant), failed to react by Quchterlony test with the AgE but reacted strongly with the BPA-R. Further immunological as well as chemical studies will be necessary to elucidate the antigenic relationship between these moieties.G~nm-Frnm, B. W., .ET BRUNET, R. Isolation of a basic protein antigen of low ragweed pollen. Can.J. Biochem. 49,396-488 (1976).Une mtthode de fractionnement conduisant B la preparation d'un antig6ne proteique basique @PA-R) de pollen de jacobQ a t t t mise au point. Cet arntighne est un allergtne puissant. I1 est homogtne en chromatographie sur sarboxymdthyl-Sephadex et en gel-filtration sur Sephadex G-108. Cette derni&e technique perrnet d'estimer le poids moltculaire de BPA-R i 3 28 000. Par son comportement physico-chimique et immunologique %e BPA-R semble se distinguer de plusieurs autres antigtnes hautement purifits et couramment isoles du pollen de jamb&.A 19arnalyse d'Quchterlony, le BPA-R et un antighne prottique acide hautement purifit (AgE) donnent des reactions d'identitd i m~~1 s l o g i q u e partielle typique avec les sQums anti-jacobCe de lapin, lesquels sont produits par layperimuniation B 19aide de B'adjuvant complet de Freund. Par contre, les antiskrums de lapin produits par Ie BPA-R (& l'aide de 19adjuvant incomplet de Freund) suivant un prockdt abrtgt5 sont hsapables de r h g h avec 1'AgE lorsque soumis au test d'Ouchterlony, mais ils reagissent fortement avec le BPA-R. D'autres ktudes immunologiques et chimiques devront &re faites pour klucider %a relation antbtnique entre ces protkines.Recent studies utilizing modern biochemical fractionation techniques ( 1-31 have resulted in the preparation of two highly purified acidic protein antigens AgE and AgK, both of which are potent allergens. These investigations, as well as more recent ones (Mi), indicate that ragweed pollen contains multiple allergens, but the present knowledge pertaining to immunologic and structural relationships amongst the allergens remains obscure* Studies are in progress in this laboratory to i...

Sonic extracts of B. pertussis were fractionated by chromatography employing DEAE-cellulose. Mouse protective antigen (MPA) was absorbed to the column and was found to be eluted over a range of salt concentrations from 0.05 to 0.35 M NaCl in dilute phosphate buffer, pH 7.2. The MPA was freed from nucleic acid impurities since these remained fixed to the column and could only be eluted with salt concentrations of 0.5 to 2.0 molarity. Some impurities of protein nature passed directly through the column. The measurable precipitating antigens associated with the crude extract were fractionated into two groups by the DEAE-cellulose. Dilute buffer elutions removed material that developed several cathodic bands by immunoelectrophoresis. More concentrated salt buffers eluted materials that exhibited one anodic band by immunoelectrophoresis against the whole B. pertussis antiserum. The measurement of significant potencies of MPA in the absence of either cathodic or anodic precipitinogens suggests that the latter represent impurities which may or may not have a relation to other known biological activities associated with B. pertussis (e.g., toxin).Certain discrepancies between mouse protective antigen and histamine-sensitizing factor based on the lack of proportionality of the activities from fraction to fraction suggest that their chemical natures are dissimilar.