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Anti-immunoglobulin analysis by diffusion patterns of inhibition and facilitation of complementary lysis in agar. I. Diffusion-lysis patterns of heterologous guinea pig anti-immunoglobulins.

Anti-rabbit immunoglobulin-containing sera were produced by immunizing guinea pigs with guinea pig red cells sensitized with rabbit-produced haemolysin against them. Such sera, and their 7S and 19S fractions, were radially diffused in agar containing sheep red cells sensitized with rabbit haemolysin and fractions thereof. After diffusion, the preparations were treated with guinea pig complement, which produced partial lysis in the background and a series of alternating rings of more and less lysis than that in the background. These were interpreted as a due to the presence of at least four anti-immunoglobulins (anti-Ig's) as follows: a 19S anti-Ig which inhibited lysis by 7S and 19S haemolysin; a 7S anti-Ig which facilitated lysis by 7S and 19S heamolysin; a 7S anti-Ig which inhibited lysis by 7S and 19S haemolysin; a 7S anti-Ig which facilitated lysis by 19S haemolysin. Similar patterns were obtained using correspondingly produced sera against mouse immunoglobulin, and sensitizing the sheep cells in the agar with mouse-produced haemolysin.

Animals

Diffuse parenchymal amyloidosis of lungs and breast. Its association with diffuse plasmacytosis and kappa-chain gammopathy.

A patient had systemic amyloidosis that extensively involved the lungs and breasts. Diffuse parenchymal pulmonary amyloidosis is rare but well described. Involvement of the breast in systemic amyloidosis is, however, most unusual. This patient's amyloidosis was associated with diffuse plasmacytosis and a kappa-chain gammopathy. The plasmacytosis was most prominent in the renal interstitium. Immunoperoxidase staining of the renal infiltrate and breast demonstrated IgG/kappa-staining plasma cells exclusively, suggesting that these cells were a monoclonal proliferation that contributed to the patient's M-protein and possibly to the patient's amyloid deposits.

Amyloidosis

Effects of hemodialysis and anemia on pulmonary diffusing capacity, membrane diffusing capacity and capillary blood volume in uremic patients.

The study aimed at investigating pulmonary function in uremic patients, emphasizing the lung diffusing capacity for CO (DLCO) and its membrane and pulmonary capillary blood volume (Vc) components. The study sample comprised 25 uremic patients without clinical/radiological evidence of lung disease. They were enrolled in a chronic hemodialysis (HD) program and had anemia requiring transfusions. The subjects were tested for their lung function before and after both a first HD and a HD with blood transfusion (BT) that followed a few days later. After HD-induced removal of body fluid, and increase in pre-HD reduced forced vital capacity, alveolar volume and mid-expiratory flow rate (FEF25-75%) was observed. HD-induced DLCO decrease (p less than 0.005) was observed and was related to decreased Vc. The second HD with BT increased DLCO, due to partially normalized Hb. On average, a 7.2% DLCO increase corresponded to each 10-g/l Hb rise. In conclusion, (1) the beneficial effect of HD in uremic patients reverts the small-airway obstruction; (2) the lower values of DLCO in these patients are due to reduced Hb and HD causes further DLCO reduction via decrease of Vc, and (3) HD with BT still increases DLCO because improvement of Hb predominates.

Adult

Anti-immunoglobulin analysis by diffusion patterns of inhibition and facilitation of complementary lysis in agar. II. Diffusion-lysis as a method for recognizing in vivo immunosuppressive activity of anti-immunoglobulins.

This paper provides evidence that it is possible to prepare facilitating anti-mouse immunoglobulin (that is, anti-mouse immunoglobulin which facilitates complementary lysis of red cells sensitized with mouse-produced haemolysin) which, when injected into mice 24 hours before an injection of sheep red cells, very markedly reduced the number of haemolysin-producing cells detectable in spleen four days later. The diffusion-lysis method was used to recognize this and other anti-Ig's in heterologous antiserum and fractions thereof. The effective antibody was in the gamma2 fraction of antiserum produced in guinea pigs by injecting them with guinea pig red cells sensitized with mouse-produced haemolysin. This method of immunizing was used in order to stimulate the production of antibody against immunoglobulin which had undergone the configurational change characteristically occurring when antibody unites with antigen. The 19S fraction of the antiserum contained inhibiting anti-mouse immunoglobulin (anti-mouse immunoglobulin which inhibits complementary lysis of red cells sensitized with mouse-produced haemolysin) and interfered with immune depression by the gamma2 fraction. It is postulated that the gamma2 fraction induces complementary lysis only of lymphocytes whose surface immunoglobulin receptors have bound antigen and undergone configurational change. It is suggested that facilitating anti-immunoglobulin of the type described is responsible for immune suppression by anti-lymphocyte serum (ALS). Facilitating anti-mouse immunoglobulin was demonstrated in two samples of ALS (anti-mouse) which were active in suppressing graft rejection, but inhibiting anti-mouse immunoglobulin only was found in a sample which was ineffective in suppressing graft rejection.

Agar

Diffusion-perfusion inhomogeneity and alveolar-arterial O2 diffusion limitation: theory.

Unequal distribution of pulmonary O2 diffusing capacity (D) to pulmonary blood flow (Q) (D/Q heterogeneity) leads to decreased alveolar O2 exchange efficacy. It is shown on simple models that the effect increases with increasing amount of inequality and with increasing value of the equilibration index, D/(Q beta) (beta, increment in blood O2 content per partial pressure increment). This inhomogeneity effect, if not taken into account, leads to spurious increases of D in hypoxia and with elevated O2 uptake.

Animals