Brucella abortus strain 19의 S-R Variation과 혈청 살균작용 = Increased sensitivity of Brucella SR-form variants to the brucellacidal action of immune sera

다국어 초록 (Multilingual Abstract)

In brucellosis, the brucellacidal activity of immune sera appears decreased when compared with that of normal ones: The degree of form dissociation, however, turned out to have a deep relationship with thesensitivity of the cells to the brucellacidal action of both normal and immune sera.
An experiment was carried to see the comparative activity of sera, and the following results were obtained.
1) Employing 0.2 % acriflavine solution, immune serum and physiological saline, a slide agglutination test was carried out to differentiat en,xariotfs -form variants which were obtained after 10 successive cultures in brucella-immune serum containing broth.
2) S-form is the typical normal cell, which shows strong specific immune agglutination reaction with immune serum, but shows no reaction at all with acriflavine and saline solu bons. SR-form ' represents the colony which reacts typically with anti-serum as in S-form but also shows a moderate reaction with acriflavine solution. R-form is the extremely dissociated colony which agglutinates spontaneously even in saline.
3) Differenciation of these three forms was further confirmed by a test tube agglutination reaction with lead acetate solution.
4) In a serum brucellacidal test, S-form cells were found more readily killed in normal serum than iri immune one when the serum concentration was comparatively high. SR-forms, however, turned out to show no significant difference in susceptility to the action of normal and immune sera, suggesting. Some antigenic changes may-have occurred in SR-forms,. Even though a -slide' agglutination test did not reveal the differences.
5) By three hours' treatment in saline at 37℃, the initial viable count of cell suspension, 1ⅹ10⁴/ml, was decreased roughly to one thousandth in S-form, while to one hundredth in SR=form, suggesting that SR-forms are comparatively resistant to the toxic action. Of saline.