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Biomedical subjects

H Metzger

Publications and source records attributed to H Metzger.

At least 235 records · Page 13Linked to original sources
PubMed1971

Electron microscopic localization of immunoglobulin E on the surface membrane of human basophils.

We have examined human leukocyte preparations for the presence of surface-bound IgE by electron microscopy. Basophil-enriched leukocytes were reacted with burro anti-IgE, a hybrid antibody to burro IgG and ferritin, and ferritin, with or without prior incubation of the cells with an IgE myeloma protein. In the absence of preincubation with IgE small amounts of ferritin were fixed to the surface of basophils but on no other cells. When cells were preincubated with IgE the amount of ferritin fixation on the basophils was markedly increased and a small amount of ferritin was also bound to platelets but again to no other leukocytes. The distribution of ferritin on the basophil surface appeared dependent upon the temperature at which the cells were kept during and after reaction with the various reagents. Basophil sections from cells kept at 0 degrees C had ferritin bound to the surface membrane in patches distributed around the entire circumference. Basophil sections from cells prepared at room temperature had ferritin distributed assymetrically covering a surface membrane segment one-fifth to one-half of the circumference. In control studies in which monomeric IgG was substituted for the IgE and burro anti-IgG was used instead of burro anti-IgE, no cellular fixation of ferritin was observed.

Animals↗
PubMed1971

Site-directed cross-linking: a new approach to mapping antibody combining sites.

The gammaA myeloma protein 315 from the mouse was affinity-labeled with m-nitrobenzene diazonium fluoroborate which, as shown previously, leads to selective modification of the tyrosine at position 34 in the light chains of this protein. The azotyrosine bond was reduced with dithionite to form 3-aminotyrosine. The aryl amino group of the aminotyrosine was selectively reacted with the bifunctional reagent 1,5-difluoro-2,4-dinitrobenzene. Cross-links were formed between the aminotyrosine and at least two residues-one on the same light chain and one in the Fd region of the heavy chain. Since affinity labeling of various antibodies with diazonium reagents has frequently led to azotyrosine formation, the approach described in this paper should have general applicability.

Animals↗