Cellular events in the IgE antibody response

Atopy as a minimal immunodeficiency?

Despite impressive recent advances in the understanding of the chemical and cellular bases of the reaginic response, the pathogenesis of atopic diseases still remains a matter of speculation. The frequent finding of atopic diseases in some primary immunodeficiencies such as selective IgA deficiency and the Wiskott-Aldrich syndrome offers a unique opportunity for studying the immune mechanisms underlying the genesis of atopy. Recent studies in subjects with selective IgA deficiency have challenged the well known hypothesis that atopy is the result of defective "immune exclusion" by the secretory immune system. A number of immunological features found in the primary immunodeficiencies associated with atopic disorders suggest that defective homeostatic mechanisms regulating reaginic responses may play a major role in the pathogenesis of atopy. A thorough analysis of these disease combinations may help to generate new working hypotheses concerning the immune pathogenesis of atopic diseases.

Isolation and partial characterization of the allergen in mountain cedar pollen

A biologically active fraction from a crude extract of mountain cedar pollen has been purified and partially chemically characterized. An ammonium bicarbonate extract of commercial defatted pollen was fractionated by G-100 Sephadex chromatography and the biologically active fraction was found to be homogeneous by polyacrylamide gel electrophoresis and N-terminal amino acid sequence analysis. The biologically active component is a 50,000 dalton protein whose N-terminal amino acid sequence is Asp--Asn--Pro--Ile--Asp. These findings provide a further purified pollen allergen for immunologic studies and the first such purified allergen having clinical significance in a limited geographic region.

Lymphocyte transformation in extrinsic bronchial asthma

Lymphocytes from sixteen patients with extrinsic bronchial asthma and sixteen normals were investigated for their in vitro reactivity to stimulation with phytohaemagglutinin (PHA) and concanavalin A (Con A). No significant differences in maximum lymphocyte responses to PHA or Con A, either in the presence of foetal calf serum or autologous plasma, were found. The significance of these results in relation to T suppressor cell control of IgE formation is discussed.

Self and non-sense: an organism-centered approach to immunology

This paper provides a conceptual framework to accommodate important recent developments in immunology (genetic determination, cellular interactions, suppression). The basic idea is to look at the immune system as a closed network of interactions which self-determines its ongoing pattern of stability and its capacities of interaction with its environment. Thus, all immune events are understood as a form of self-recognition, and whatever falls outside this domain, shaped by genetics and ontogeny, is simply nonsensical. This paradigm, stemming from the ideas of Jerne, represents almost a logical inversion of the Burnetian idea of self-discrimination. A detailed discussion of the immunological evidence that substantiates this view is presented, together with some new concepts (eigenbehavior, cognitive domains). Although the paper is addressed to biologists and immunologists, we make extensive use of system-theoretic notions in a non-mathematical form (recursion, nets and trees, self-organization).

TB mice. A model of high and long lasting reaginic responders

Reaginic (IgE) antibodies are normally difficult to induce in laboratory rodents. The TB inbred mice constitute an exceptionally suitable model for the study of reaginic responses because of their ability to mount a strong and long lasting (over 4 months) IgE antibody response to hapten carrier conjugates, such as DNP3-OVO, administered in the presence of adjuvant. The maximum individual PCA titres determined for the sera of 8 animals after primary sensitization were in the range of 2,048 to 65,536 (geometric mean: 9,733) and after secondary sensitization the maximum individual PCA titres augmented to a level of 8,192 to 131,072 (geometric mean: 50,490).

The measurement of total serum IgE levels in rats

A direct solid phase radioimmunoassay for the measurement of total serum IgE in the rat has been developed. The assay is very sensitive with a lower limit of detection of 5 ng/ml. The intra and interassay reproducibility proves to be very acceptable and the specificity is demonstrated by looking at the interferen-e by other immunoglobulins. Preliminary results on total serum IgE levels are given.