IgA class reticulin antibodies in relatives of patients with coeliac disease

IgA class reticulin antibodies were not found in patients with Crohn's disease, ulcerative colitis, and hiatus hernia despite a significant incidence of IgG class reticulin antibodies. None of 56 normal healthy subjects was positive. In contrast, 13 (76%) of the sera from 17 patients with coeliac disease on normal diet were positive for IgA class antibodies as were 19 (20%) of 93 first degree relatives. Seventy-three relatives underwent jejunal biopsy. Grade III (flat) histology was found in 13 and, of these patients, 10 (77%) showed IgA class reticulin antibody in their serum. It is suggested that determination of IgA class reticulin antibodies was a useful test to determine which relative must be biopsied.     

Command neurons in the unconditioned reflex arc of the grape snail

Independent intracellular activation of any one of the five identified neurones elicits a behavioral act of pneumostome closing. Similar closing is evoked by adequate stimulation of different modalities. Comparison of unconditioned reflex properties and characteristics of responses of the studied cells leads to the conclusion that neurones under discussion are command elements for the unconditioned reflex. Command neurones respond to all sensory stimuli which can evoke reflex closing. There is a lot of synchronous EPSPs in their spontaneous activity, but no action potentials. A spike discharge of command neurones evoked by an adequate stimulus always precedes the effector movements but there is no action potentials during the pneumostome closing. Conclusion is made that the functional role of command neurones in the unconditioned reflex arc consists in evaluating the sensory input and in triggering motor programmes.     

Lymphocytes' cytotoxicity towards cells of human lymphoblastoid lines in patients with rheumatoid arthritis and systemic lupus erythematosus

A research study and discussion of antiinterferon immunoglobulin in the treatment of rheumatoid arthritis and systemic lupus erythematosus, and its possible value in the treatment of allergic diseases, autoimmune diseases and other diseases where it is presumed there may be an autoimmune genesis.     

Isotope effect in the binding of tritium and 14C-labelled cortisol to corticosteroid-binding-globulin in serum

We have determined the free cortisol concentration in serum using either the Amicon MPS-1 ultrafiltration-centrifugation method (I) or equilibrium dialysis (II). If procedure I was used we found that [1,2,6,7-3H]-, and [4-14C]cortisol had a lower affinity than unlabelled cortisol for corticosteroid binding globulin (CBG). The binding affinity (Ka) to three separate CBG-containing samples was 8-18 times lower for [1,2,6,7-3H]cortisol and 30-90 times lower for [4-14C]cortisol, when compared with that of unlabelled cortisol. This difference in affinity to CBG was not observed if method II was used for the free cortisol determinations. The observed isotope effect in method I is not caused by unspecific binding to material such as the Amicon MPS-1 chamber or to impurities in the tracer. We suggest that the centrifugation step during ultrafiltration changed the conformation of CBG, thereby reducing its affinity for labelled cortisol. It is concluded that incorrect results will be obtained if radiolabelled is cortisol used for determining the free cortisol content of plasma with the Amicon MPS-1 device.     

LP-BM5 virus causes changes in lactic dehydrogenase and oxygen radical production in splenocytes of C57BL/6J mice

The LP-BM5 murine leukemia virus causes acquired immunodeficiency syndrome in C57BL/6J mice (MAIDS), similar to that of AIDS in humans. The objective of this study was to determine the effect of LP-BM5 viral infection on cellular activation and membrane integrity of splenocytes. Oxidative burst in splenocytes in response to exposure to PMA (20 microg/ml) was significantly higher (p<.02) in infected than in control mice at two weeks post-infection using luminol-enhanced chemiluminescence. By 13 weeks post-infection superoxide anion production in infected mice was significantly lower when compared to controls coinciding with decreased proliferative response to mitogens. The extent of cell membrane damage as indicated by lactic dehydrogenase (LDH) activity in serum was significantly higher in infected than in control mice (p<.001). The results from this study suggests that LP-BM5 virus causes an initial stimulation of cellular activity followed by a decreased cell activation characterized by decreased proliferation of splenocytes and decreased oxygen radical production. Decreased cell membrane integrity indicated by increased LDH activity may partly be responsible for these changes.