ＮＺＢ／ＷＦ１マウスの組織沈着免疫複合体　　（ＩｇＧ‐ＩｇＧ‐抗核抗体／リウマトイド因子）の研究

The components of the immune complexes deposited in the lesion of lupus like glomerulonephritis in NZB/W F₁ mice been recognized to be mainly composed of DNA as an antigen and anti-DNA antibodies. However, there are many problems to be elucidated the components of immune complexes. Recently we developed new procedure to dissociate immune complexes in glomeruli by applying various reagents on the frozen kidney sections. Present paper described is to study a composition of immune complexes in glomerulii of NZB/W F₁ mouse and also an activity of antinuclear antibody in the serum and eluate from the mouse kidney cross-reactive with mouse or rat IgG, mainly Fc fragments. Granular staining for mouse IgG in the mesangium and glomerular capillaries were observed almost of all 6 month- to 12 month-old NZB/W F₁ mice. These frozen sections of the kidney were performed the dissociation test of mouse IgG, IgM and C₃ from the glomeruli. The frozen sections were incubated with 5% of mouse IgG, mouse Fc fragment (frg), rat IgG, rat Fc frg, human Cohn fraction 11 (Frll), 0.5% of DNA and nucleohistone and PBS for 6 hours at room temperature chang in PBS, and then these specimens were stained with FITC-conjugated antimouse IgG, IgA, IgM and C₃ antibodies. Among these, the IgG deposits in the glomeruli disappeared or decreased following incubation with mouse IgG and rat IgG, especially with mouse Fc frg and rat Fc frg. On the contrary, the IgG deposits did not disappeared following incubation with human FrII, rabbit FrII, DNA, nucleohlitone and PBS. The activity of antinuclear antibody (ANA) was studied whether ANA was crossreactive with other reagents, mainly mouse IgG. Activity of ANA in the serum disappeared after incubation with mouse IgG, mouse Fc frg, rat IgG and rat Fc frg, but not with human IgG and rabbit IgG. Activity of ANA in the eluate disappeared after incubation with mouse IgG, mouse Fc frg, rat Fc frg, DNA and nucleohistone, but not with human and rabbit IgG. These results suggested that the immune complex deposits in the glomeruli consisted of IgG (presumably denatured)-IgG ANA/IgG rheumatoid factor.