Simple determination of the L.E. factor. Loose body test and nucleus agglutination inhibition test.

(2) The L.E. Cell Test.-In about 80 per cent. of the proved cases the Hargraves test is positive. A theoretical objection to this test is that it employs phagocytosis which is a secondary reaction in vitro as indicator. The fixation of the specific L.E. gamma globulin to nuclei, which constitutes the first phase of the L.E. cell formation and results in loose body formation (Aisenberg, 1959; Rifkind and Godman, 1957; Rohn and Bond, 1952; Robineaux, BuffM, and Kourilsky, 1956), is not considered sufficient proof, but it is accepted that in some cases phagocytosis cannot occur because S.L.E. serum inhibits phagocytosis (Finch and Detre, 1958), has a lowered complement content in the active phase, and may show anti-complementary activity (Formijne and van Soeren, 1958). The practical disadvantages of the L.E. cell test are its laboriousness and the reading-off difficulties in weaklypositive cases.