Immunological function in dystrophia myotonica

Humoral and cellular immunity have been investigated in 15 patients with dystrophia myotonica. No abnormalities in total serum levels of the five major immunoglobulin classes were found but there was a rise in the mean serum level of beta(1)A complement. Altogether, 54% of patients failed to make antibody to tetanus toxoid as compared with 1% of controls: 13% of patients failed to make antibody to Salmonella typhi H antigen as compared with no failure of this function in control subjects. There was a reduced uptake of tritiated thymidine by whole blood lymphocyte cultures spontaneously, while in the presence of phytohaemagglutinin (PHA) and both autologous and fetal calf serum the uptake was normal. It is suggested that there may be a wider derangement of immunological function in dystrophia myotonica than previously thought.

Cytotoxicity of adenovirus-antibody aggregates: sensitivity to different cell strains, and inhibition by hexon antiserum and by complement

Adenovirus-antibody aggregates under defined conditions are cytotoxic in vitro. All members of adenovirus groups I, II, and III caused toxicity upon aggregation. The toxicity of the clusters is exerted by the virions. Toxicity is temperature dependent and may be caused by a mechanism similar to that used in viral penetration. Cells permitting direct viral penetration were all sensitive to the toxic aggregates. The toxicity seems to be related to hexon antigens on the surface of the virions since antihexon sera neutralized the toxicity. No evidence was obtained showing that pentons are required for this kind of cytotoxicity. Adenovirus types 3, 5, and 9 were used in the experiment. Cytotoxicity was estimated by the (51)Cr release assay. Complement factors could be excluded as mediators of the cytolytic reactions. Instead, complement was shown to prevent the formation of toxic aggregates or to neutralize the toxicity of preformed ones.

Surface antigens of mammalian cells as genetic markers. II

A second surface antigen, B(L), lethal in the presence of specific antibody and complement has been identified on some human cells and shown to behave as a good genetic marker. It is autosomal, unlinked to the human A(L) antigen previously described, and unlinked to 15 other human genes. The A(L) antigen, which is linked to the lactic dehydrogenase A gene, is found on the HeLa, the cultured human fibroblast, and in small amounts on the human lymphocyte. B(L) occurs on HeLa cells, on cultured human fibroblasts, and on human lymphocytes, but not on human RBCs. Hybrid cells formed by fusion of human and Chinese hamster cells have been prepared containing each of the four possible combinations of these two markers. Highly selective antisera sensitive to each marker separately can be obtained. The use of single-cell plating to demonstrate the presence of the antigens and of hybrid cells containing desired combinations of the markers facilitates study in this system.

Histamine release induced by himan leukocyte lysates: implication of a specific, complement-independent, noncytotoxic reaction

The characteristics of histamine release induced by human leukocyte lysates were determined. Intact human leukocytes released histamine during incubation with leukocyte lysates. Maximal release occurred under physiological conditions of temperature and pH, and both Ca(2+) and Mg(2+) were required. The addition of ethylenediaminetetraacetic acid abruptly inhibited release. Complement was not required, and serum actually inhibited release. Histamine release was maximal at lysate concentrations of 0.25 to 1.0 mug of protein per ml, and it was reduced at either higher or lower concentrations. Leukocytes continued to exclude trypan blue and maintained chemotactic activity after histamine release. Leukocytes released histamine independently of cellular protein or enzymes. Histamine release induced by leukocyte lysates was interrupted by subsequent removal of the lysate. The data suggest that this histamine release occurs by a specific, complement-independent, noncytotoxic process which resembles, but is not identical with, antigen-induced histamine release. The system has several unique characteristics which suggest that it is a novel form of inflammatory histamine release. This system should provide a useful in vitro model for studies of cellular processes in human inflammation.

The association of respiratory infection, recurrent hematuria, and focal glomerulonephritis with activation of the complement system in the cold

The study of the activation of C3, C5, and C7 associated with the conversion of C3 in the serum of a 9-yr old girl after incubation at 0 degrees C for 6-8 h without utilization of C1, C4, and C2 is described. The patient has upper respiratory infections associated with recurrent gross hematuria, focal glomerulonephritis, and transient renal insufficiency. Histological lesions demonstrated the presence of B1c globulin IgA and properdin in the glomeruli. The activation of complement (C) in the cold requires the patient's IgA. Removal of IgA from the serum by immunoadsorption prevents activation and conversion of C3. Bactericidal and phagocytic activity is also impaired after incubation. C3 proactivator (C3PA) level is reduced before and after incubation. Properdin level drops after incubation. These findings suggest that the activation of C3 which is demonstrable in vitro may be a continuous process in vivo.