• 1 January 1964
    • journal article
    • research article
    • Vol. 7  (4) , 403-+
Abstract
The reaction of the rheumatoid factor (RF) with 7S gamma-globulin antibodies of nine persons immunized with sheep erythrocytes was studied. All of a panel of rheumatoid sera with high Waaler-Rose titres agglutinated sheep cells sensitized with the human anti-sheep cell antibodies and O Rh positive cells sensitized with the "diagnostic" anti-CD serum Ripley. The RF measurable with these systems could be absorbed to diphtheria toxoid-human antitoxin precipitate, whereas the absorption with egg albumin-rabbit anti-egg albumin precipitate did not result in any appreciable titre reduction. However, the eluate from the rabbit precipitate was highly active in these systems, whereas Rh positive cells sensitized with anti-Rh sera suitable for Gm(a) typing were not regularly agglutinated. A markedly greater concentration of native than of heat-aggregated gamma-globulin was needed for inhibition of the agglutination by the RF of cells heavily sensitized with the human anti-sheep cell antibodies. No appreciable difference in this respect was seen when using lightly sensitized cells. Only the heavily sensitized cells fixed complement. The "natural" 7S gamma-globulin antibodies against sheep cells were neither suited for demonstration of RF nor did they fix complement. Sheep cells coated with 7S gamma-globulin antibodies of a Gm(a+) person were agglutinated by a non-rheumatoid anti-Gm (a) serum, and this system was well suited for Gm(a) typing, whereas cells coated with antibodies of a Gm(a -) person were not agglutinated. Rheumatoid anti-Gm(a) sera agglutinated cells sensitized with antibodies of both Gm(a +) and Gm(a -) persons. Using cells coated with Gm(a -+) antibodies, some distinction between Gm(a +) and Gm(a -) sera could be obtained under carefully controlled conditions. The use of a Gm(a -) coat resulted in a slight difference in the inhibiting capacity, which had no relation to the serum''s Gm(a) type. The results suggest that the reaction of the RF with sheep cells heavily sensitized with human anti-sheep cell antibodies is essentially an interaction of the RF with immune aggregated gamma-globulin, whereas when using lightly sensitized cells the individual gamma-globulin molecules play a prominent role.