Joel K. Weltman

Relatedness among proteins: A new method of estimation and its application to immunoglobulins☆

Abstract 1. 1. A method is presented for the determination of relatedness among proteins based upon statistical analysis of differences in amino acid composition. 2. 2. Analytical results of this method correlate closely with comparisons based upon the sequence of amino acids within the three families of related proteins tested: hemoglobins, light chains of myeloma proteins and cytochromes. 3. 3. The method is applied to immunoglobulins for which amino acid sequence data are not available and general conclusions are drawn regarding the evolutionary relationships of these immunoglobulins.

IL-5: biology and potential therapeutic applications

IL-5 is the predominant cytokine associated with antigen-induced eosinophilic inflammation in the lung. The activation of Th-2 cells leads to the production of IL-5. The pro-eosinophilic effects of IL-5 include: (1) enhanced replication and differentiation of eosinophilic myelocytes; (2) enhanced degranulation of eosinophils; (3) prolonged survival time of eosinophils: and (4) enhanced adhesion of eosinophils. The effects of IL-5 are mediated via the interaction of IL-5 with receptors (IL-5R) that are expressed on the eosinophil cell membrane. Intracellular signalling produced by occupation of the IL-5R by IL-5 occurs via the JAK-STAT system. IL-5 is a 45kDa glycoprotein consisting of two identical polypeptide chains. The 5′-promoter region of the IL-5 gene contains elements that are down-regulated by glucocorticoids. Anti-IL-5 reagents have the potential to suppress IL-5 activity without the side effects of glucocorticoids. Studies using monoclonal antibodies (mAbs) against IL-5 have established the feasibility of suppressing eosinophilic inflammation by specifically blocking IL-5 activity. Studies with antisense IL-5 are beginning to provide the basis for non-glucocorticoid, sequence-specific oligonucleotide inhibitors of IL-5. Research has begun on the development of mAbs and antisense oligonucleotide inhibitors of IL-5 that can be inhaled and applied topically.

An Analysis of the Role of IgE in Intolerance to Aspirin and Tartrazine

Total serum IgE and eosinophil count were determined for 30 patients with in‐tolerance to aspirin. Total IgE levels in the aspirin intolerant patients were similar to those expected in a. non‐atopic population. In contrast, total eosinophil count (TEC) tended to be elevated in the aspirin intolerant group. Elevated TEC was observed both in bronchospastic (57%) and in urticarial (25%) aspirin intolerance. Specific anti‐aspiryl and anti‐carcrazyl antibodies of the IgE class were assayed by the galactosidase immunosorbent test [GIST] * . IgE anti‐aspiryl antibodies were possibly eletected in one patient, but did not correlate with clinical intolerance to aspirin. It is unlikely that the clinical symptoms and the eosinophilia of intolerance to aspirin and tartrazine are mediated by antibodies of the IgE class.

A galactosidase immunosorbent test for human immunoglobulin E

We report here the development of a galactosidase-immunosorbent test (GIST) for immunoglobulin E (IgE) antibodies in which the amount of galactosidase adsorbed to a cellulose disc is a single valued function of IgE concentration in human serum. Rabbit anti-IgE immunoglobulin insolubilized on cellulose discs is incubated sequentially with human serum, sheep anti-IgE serum, and a covalent conjugate of rabbit antisheep immunoglobulin with the enzyme beta-D-galactoside galactohydrolase (E.C.) 3.2.1.23). Colorimetric assay of enzyme conjugate adsorbed to discs permits quantitation of 1.0 to 25 ng of IgE per test. Concentrations of IgE in 48 sera as measured by the GIST gave a linear correlation coefficient of 0.97 with IgE concentrations as determined by radioimmunoassay. Preliminary studies indicate that the GIST makes possible nonisotopic measurement of ragweed-specific IgE antibiotics in human serum. The GIST for IgE is simple to perform and requires neither short-lived radioisotopes, expensive scintillation detection equipment, nor scarce, purified IgE.

Fluorescence polarization study of a human IgA myeloma protein: absence of segmental flexibility.

Fluorescence polarization measurements of dansyl‡ conjugates of an IgA myeloma protein (DWY) revealed no independent internal rotations of Fab regions within the immunoglobulin molecule. Rotational correlation time (\gf) calculated from time-average emission anisotropy (Ā) in sucrose solutions was 147 nsec. A kinetic plot of fluorescence polarization anisotropy (A(t)) following a nanosecond pulse of excitation of dansyl-DWY was linear with time in contrast with the corresponding plot reported for anti-dansyl IgG antibodies (Yguerabide, Epstein & Stryer, 1970). Rotational correlation time (φ) of dansyl-DWY obtained from time dependence of A(t) was 493 nsec. The discrepancy between φ and \gf may be attributed to rapid depolarizations of covalently bound dansyl groups perhaps due to independent rotations of amino-acid side chains or of small flexible regions of the DWY molecule.

Update on histamine as a mediator of inflammation.

Histamine is an important mediator and regulator of inflammation. Histamine acts via H1, H2, and H3 receptors that are functionally coupled to G-proteins and histamine release is regulated by cytokines that act as histamine release factors. Histamine suppresses the immune response and deviates the immune response toward the Th2 pathway.

The use of inhaled corticosteroids in asthma.

Inhaled corticosteroids are the most important therapeutic agents for the pharmacological control of pulmonary inflammation in asthma. There is concern, however, about the occurrence of side effects with the long-term use of inhaled corticosteroids. Because of the potential seriousness of some of these side effects, patients should be monitored carefully and preventively treated for the side effects. Various noncorticosteroid medications have been recommended in guidelines as substitutes for inhaled corticosteroids for daily use as long-term controllers in asthma, e.g., sustained-release theophylline, long-acting beta-agonists, leukotriene modifiers, cromolyn, and nedocromil. However, of the long-term controller medications recommended in the guidelines, only inhaled corticosteroids have to date, been shown clinically to reduce asthma fatalities and to prevent asthma induced lung remodeling.

Decimative Multiplication of Entropy Arrays, with Application to Influenza

The use of the digital signal processing procedure of decimation is introduced as a tool to detect patterns of information entropy distribution and is applied to information entropy in influenza A segment 7. Decimation was able to reveal patterns of entropy accumulation in archival and emerging segment 7 sequences that were not apparent in the complete, undecimated data. The low entropy accumulation along the first 25% of segment 7, revealed by the three frames of decimation, may be a sign of regulation at both protein and RNA levels to conserve important viral functions. Low segment 7 entropy values from the 2009 H1N1 swine flu pandemic suggests either that: (1) the viruses causing the current outbreak have convergently evolved to their low entropy state or (2) more likely, not enough time has yet passed for the entropy to accumulate. Because of its dependence upon the periodicity of the codon, the decimative procedure should be generalizable to any biological system.

An Immuno-Bioinformatic Analysis of Zika virus (ZIKV) Envelope EProtein

By means of the combined use of B cell epitope prediction (Bepipred) and measurement of information entropy (H) in envelope (E) protein of Zika virus (ZIKV) isolated from infected humans, five amino acid sequences were identified as containing probable epitopes. These five predicted epitopic sequences contained nine amino acid positions where H>0.0. It is proposed that some of the observed entropic positions may reflect mutational escape of the ZIKV from the immune response of the infected host and that such information, applied together with conventional epitope prediction, can guide and facilitate design of anti-ZIKV vaccines.

Cytokines: regulators of eosinophilic inflammation.

Cytokines are glycoproteins that are secreted and that regulate immunologic inflammation. The cytokine system is characterized by much redundancy and cross-reactivity. Of the more than 100 cytokines that have been identified, interleukin-5 (IL-5) and the chemokine (chemotactic cytokine), eotaxin, are the most selective for cells of eosinophilic origin. Because of this relative specificity, and because of their important immunoregulatory roles, IL-5, eotaxin, and their receptors IL-5R and CCR3 are potential targets for non-glucocorticosteroid pharmacological treatment of eosinophilic inflammation.