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M W CHASE

Publications and source records attributed to M W CHASE.

10 recordsLinked to original sources
PubMed1965

INDUCED UNRESPONSIVENESS TO SIMPLE ALLERGENIC CHEMICALS. II. INDEPENDENCE OF DELAYED-TYPE HYPERSENSITIVITY AND FORMATION OF CIRCULATING ANTIBODY.

Normal guinea pigs fed chemical haptens develop a specific state of unresponsiveness, inhibiting subsequent development of dermal sensitization with the same hapten and modifying profoundly the synthesis of anaphylactic antibody in response to hapten conjugated to guinea pig proteins. The degree of unresponsiveness has been tested by exposing hapten-fed animals to intense haptenic stimulation. Animals of groups that were demonstrably unresponsive to picryl chloride could be made to form hapten-specific antibody by injecting picrylated bovine gamma globulin. Specific anaphylactic-type antibodies, presumably 7S gamma(1), were synthesized, and in animals given PBGG adsorbed to alumina there arose a measurable concentration of precipitating antibody, presumably 7S gamma(2), perhaps slightly earlier than in similarly treated control animals. Attempts to impose contact-type reactivity on such unresponsive animals met with limited success. Injection of picrylated guinea pig erythrocyte stromata in a complete Freund's adjuvant, with subsequent applications of picryl chloride to the dermis, led to definite contact sensitivity to 0.3 per cent picryl chloride, whereas parallel treatment of normal control animals induced sensitivity to 0.006 or 0.002 per cent. By this double method of stimulation, hapten-fed animals did not advance in sensitivity by reason of the secondary dermal applications of the simple chemical, whereas control animals developed increasingly higher sensitivity by these contacts in what appeared to be a stepwise manner. Picryl chloride-fed guinea pigs injected intradermally with picryl chloride either after or before forming picryl-specific circulating antibody still remained unable to develop picryl-specific contact hypersensitivity. Control animals synthesizing picryl-specific antibody subsequently responded to intradermal injection of picryl chloride with contact-type sensitivity. Interpretations of these results are discussed and the view is presented that delayed-type hypersensitivity and circulating antibodies of the varieties measured here are formed independently of each other.

Allergens↗
PubMed1963

IMMUNOLOGICAL UNRESPONSIVENESS TO SENSITIZATION WITH SIMPLE CHEMICAL COMPOUNDS; A SEARCH FOR ANTIBODY-ABSORBING DEPOTS OF ALLERGEN.

Guinea pigs fed picryl chloride to induce specific immunologic unresponsiveness cleared small amounts of venously infused antipicryl antibody at a rate equal to that of normal guinea pigs. Catabolism of passively administered picryl-specific antibody did not alter the unresponsive state of picryl chloride-fed guinea pigs or the responsive state of normal guinea pigs. Lymphoid cells of picryl chloride immunized guinea pigs produced equal amounts of picryl-specific antibody in picryl chloride-fed and normal animals. Allergen-fed guinea pigs remained unresponsive to attempted sensitization with the allergen in excess of 10 months after the final feeding, though some became feebly sensitive between 9 and 11 months. Second attempts to make unresponsive animals hypersensitive were unsuccessful. White blood cells of guinea pigs unresponsive to picryl chloride were unable to transfer delayed-type hypersensitivity for picryl chloride to normal recipients yet readily transferred tuberculin hypersensitivity.

Allergens↗
PubMed1961

Studies on fluorescent antibody staining. I. Non-specific fluorescence with fluorescein-coupled sheep anti-rabbit globulins.

1. A study has been made of the non-specific fluorescent staining of splenic imprints treated with fluorescent sheep antibody globulins. 2. In tissue imprints made with the spleens of antigen-stimulated animals, no morphological distinction was evident between areas showing non-specific fluorescence and specific fluorescence. 3. Elimination of non-specific fluorescence was not achieved by any one, or any combination of the following: (a) conjugating only gamma globulins with fluorescein isothiocyanate; (b) removal of dialyzable fluorescent products on sephadex, followed by concentration through the use of pressure dialysis; (c) use of crystalline preparations of fluorescein isothiocyanate. 4. Individual preparations of fluorescent antibodies were separated by gradient elution chromatography on diethylaminoethyl (DEAE) cellulose into fractions possessing different numbers of fluorescein radicals per molecule of globulin. 5. The coupling ratio of 50 mg fluorescein isothiocyanate (FITC) per gm of protein, as commonly advocated, can not be recommended for the precise localization of antibody globulin in tissues owing to the capacity of the coupled products to give non-specific fluorescent staining. When crystalline preparations of FITC are used instead of the amorphous product at 50 mg/gm protein, far too high non-specific fluorescence results. 6. A fraction with bright specific fluorescence and no or negligible nonspecific fluorescence was obtained from each fluorescent antibody that was prepared by using 6 to 8 mg of crystalline fluorescein isothiocyanate per gm of globulin and was then subjected to DEAE-cellulose chromatography and gradient elution to eliminate the most highly coupled molecules.

Animals↗