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Antibody has been prepared to a hydrophobic myelin protein in rabbits using several different adjuvants. This antibody was found to react with the myelin basic protein. This latter activity could be absorbed out with basic protein leaving the reactivity to the hydrophobic protein, suggesting that the two myelin proteins shared a common antigenic determinant. In addition, the hydrophobic protein appears to possess a unique antigenic determinant.

Cytochalasins A and B at low doses resulted in enhancement of the antigen-induced and anti-IgE-mediated release of histamine from human lung fragments in vitro. Both compounds appeared to effect a dose-dependent inhibition of the antigen-induced release of slow reacting substance of anaphylaxis. Although the effects observed with cytochalasin B were at least partially reversible, the effects of cytochalasin A could not be readily reversed. The cytochalasins appeared to be more effective when present during the antigen-dependent activation phase of mediator release rather than during the calcium-dependent release phase.

Forty-two perennial asthmatic children were selected for a 12-wk study using beclomethasone dipropionate. The groups included 21 steroid-dependent children (Group I) and 21 patients (Group II) whose disease was of sufficient severity that corticosteroid therapy was contemplated. All children received the drug in a dose of 100 mug 4 times daily. During the study, oral prednisone was withdrawn from the steroid-dependent children while other therapy was essentially unchanged. Group II children underwent a double-blind trial, receiving beclomethasone for 6 wk and placebo for 6 wk. Objective assessment of adrenal and pulmonary function was obtained at regular intervals. For the latter, total lung capacity and its subdivisions, airways resistance, maximum expiratory flow volume, and oxygen tension, were measured in both groups. In Group II static elastic recoil was measured also. For most tests the results were statistically significant. In both groups, 18 of 21 patients demonstrated an excellent clinical response, no evidence of adrenal suppression, and improvement in pulmonary function. Forty of 42 patients were followed for another 12 wk, and 19 of each group did well. After 20-24 wk of therapy, 16% of patients harbored monilia in their oropharynx, and 1 patient had clinical monilial stomatitis. Within the limits of the time of the study, beclomethasone dipropionate appeared to provide adequate clinical control in many chronic, severe, steroid-dependent and nonsteroid-dependent asthmatic children.

A 12-year follow-up study of children who had had operations with general anesthesia in infancy and of nonhospitalized children of the same age showed almost identical incidences of respiratory allergy in the test and control groups. General anesthesia in infacy does not predispose to respiratory allergies in childhood.

Calcium deprivation inhibits the formation and subsequent release of SRS-A as well as histamine from passively sensitized human lung fragments challenged with antigen. Antimycin A inhibits the release of histamine and SRS-A in a dose dependant fashion, while causing a mild inhibition of SRS-A formation throughout the dose range studied. These data suggest that the influx of calcium is the critical event for the generation of SRS-A within the cell.

The contractile effects of partially purified slow-reacting substance of anaphylaxis (SRS-A) and histamine were compared on isolated guinea pig tracheal spirals and parenchymal strips. Histamine was equally active on both isolated tissues in a concentration-related fashion. SRS-A (0.1--10.0 U/ml) produced a concentration-related effect on parenchymal strips, whereas the tracheal spiral was 100 times less sensitive to this mediator. The contractile activity of SRS-A on parenchymal strips was diminished by incubation with limpet arylsulfatase and antagonized by FPL 55712, a known SRS-A antagonist. SRS-A, further purified by high pressure liquid chromatography, also demonstrated this preferential activity on guinea pig parenchymal strips. These data are consistent with the hypothesis, based on previous in vivo observations, that SRS-A is a selective peripheral airway constrictor.

Nine asthmatic patients with a mean age of 14 yr received bronchial challenges with histamine and methacholine. The challenges were repeated after inhalation of 80 microgram of SCH 1000 (ipratropium bromide) and 5 mg of chlorpheniramine maleate. The provocation doses which produced a 20% fall in forced expiratory volume in 1 sec (FEV1) and the slopes of the dose-response curves were analyzed. SCH 1000 prevented methacholine-induced bronchoconstriction and chlorpheniramine prevented methacholine-induced bronchoconstriction. There was no significant change in the dose-response curve of histamine after SCH 1000 or in the dose-response curve of methacholine after chlorpheniramine. The findings indicate that the mechanisms and receptor sites involved in bronchial provocation by histamine and methacholine are distinctly different. The histamine response is unlikely to be vagally mediated because histamine-induced bronchoconstriction was not prevented by SCH 1000. Both SCH 1000 and chlorpheniramine caused significant bronchodilatation, suggesting the presence of both histamine- and vagal-dependent bronchomotor tone.

The capacity of the calcium ionophore A 23187 to induce the formation of SRS-A was used in an attempt to identify the nature of the cells that are responsible for the formation of this material. In agreement with previous observations, rat and mouse peritoneal mast cells were found to contribute very little to the total amount of SRS-A that was made, and in fact their removal from the cell suspensions resulted in an augmentation of the amount of SRS-A that was found. Discontinuous Ficoll and bovine serum albumin gradients were employed to further characterize these SRS-A-releasing cells from induced peritoneal cells. SRS-A was produced by nonspecific esterase-positive and latex-phagocytizing mononuclear cells. By electron microscopy, these cells had macrophage-like characteristics. In contrast, rat alveolar macrophages and a macrophage-like cell line of mouse origin both failed to produce large amounts of SRS-A. The results suggest that SRS-A formation may be the property of an as yet imperfectly characterized subclass of macrophages.

In the presence of L-cysteine, a selective and marked enhancement of the in vitro, immunologic release of slow reacting substance of anaphylaxis (SRS-A) from human peripheral leukocytes, sensitized monkey lung fragments, and sensitized guinea pig lung fragments was observed. In the rat, cysteine, but not sodium sulfide, enhanced the calcium ionophore (A23187)- induced release of SRS-A in vitro from mixed rat peritoneal cells and in vivo from the rat peritoneal cavity. Pretreatment of rats with cysteine also enhanced the IgGa-and anti-rat IgE-mediated release of SRS-A in vivo in the rat. These studies indicate a common biochemical mechanism involved in the formation and release of SRS-A from these different tissues and cells and further confirm the observation that the rat mast cell is not a major source of SRS-A in the rat.

Arachidonic acid stimulates the release of SRS-A from the peritoneal cavity of sensitized rats or from rat peritoneal cells incubated in vitro. When rat peritoneal cells are incubated in the presence of tritiated arachidonic acid, significant amounts of radioactivity migrate in parallel to bioactivity on purification with Amberlite XAD-8, DE-52, Silicic acid and Sephadex LH-20. Lipoxidase (E.C. 1.13.1.13 and E.C. 1.13.11.12) inactivates mouse, rat and human SRS-A in a concentration-dependent pattern. Following extensive purification, rat SRS-A is also inactivated by the 2 x crystalline suspension of lipoxidase. These findings suggest (a) that SRS-A is a metabolite of arachidonic acid and (b) because of the strict specificity of lipoxidase, that the SRS-A molecule contains a cis, cis-1, 4-pentadiene and a structure very close either to arachidonic acid, to linoleic acid or to linolenic acid.

Extracts of isolated rat peritoneal mast cells were demonstrated to contain appreciable quantities of arysulfatase activity. The enzyme was inhibited by both phosphate and sulfate ions and demonstrated a pH optimum of 5.0. The enzyme was recovered in the eluate of DE-52 columns and appeared to have a m.w. of 150,000 of Sephadex G-200 gel filtration. These findings and the anomalous kinetic behavior of the enzyme suggest that at least part of the enzymatic activity is of the arylsulfatase IIA type. While spontaneous release of the enzyme was observed, challenge of isolated rat mast cells with a goat anti-rat IgE serum resulted in a significant increase in release of the enzyme. The arylsulfatase activity extracted from isolated rat mast cells demonstrated comparable activity in inactivating slow reacting substance of anaphylaxis (SRS-A) to that described for human eosinophil and lung arylsulfatase.

Preincubation of human lung fragments with cysteine for 2.5 to 5.0 min resulted in dose-dependent, selective enhancement of the antigen-induced or anti-IgE-induced formation and release of slow reacting substance of anaphylaxis (SRS-A). Comparable effects were observed with sodium sulfide and thioglycolate but not with other more potent reducing agents or metabolites of cysteine. Sulfhydryl alkylated derivatives of cysteine were ineffective. The effects observed with the active thiols were easily reversed and could not be attributed to an action in the bioassay or on SRS-A itself. The physicochemical characteristics of the contractile activity were identical to those described for SRS-A.

The effects of Ascaris suum antigen, histamine, and slow-reacting substance of anaphylaxis (SRS-A) on the respiratory system were compared in 3 anesthetized rhesus monkeys. The agents were administered by instillation into the trachea, and the animals were studied in a volume displacement body plethysmograph. Two of the animals showed skin and bronchial sensitivity to Ascaris suum antigen and responded to it with increased pulmonary resistance and decreased dynamic compliance. A similar response was seen in all 3 animals after instillation of histamine, but SRS-A at 2 concentrations produced a predominant effect of decreased dynamic compliance with lesser alterations in pulmonary resistance. The effects of SRS-A were slow in onset and prolonged, as compared to the abrupt and short-lived effects of Ascaris suum antigen and histamine. The predominant effect of SRS-A on dynamic compliance suggests a more peripheral site of action of this mediator. In 5 monkeys allergic to Ascaris, no SRS-A could be detected in the blood at one and 5 min after antigen challenge, using the bioassay techniques.

Sera of 86 patients clinically sensitive to foods were tested by passive sensitization of human and/or monkey lung (127 tests) and the radioallergosorbent test (RAST) (72 tests), using whole-food antigens; the results were compared with skin (prick) testing. Results of the prick test correlated with history in 76% of cases; lung sensitization correlated with history in 37% and with prick test in 57%; and RAST correlated with history in 54% and prick test in 72%. It is concluded that a very large percentage of adverse reactions to foods are IgE-mediated. The prick test is of use in diagnosis, particularly when combined with RAST; the lung sensitization test is technically impractical and not a reliable indicator. The best diagnostic method is careful history with food challenge and withdrawal and rechallenge; the latter is safe except in patients with a history of violent reaction.

The ability of the calcium ionophore A23187 to release slow reacting substance of anaphylaxis (SRA-A) from human leukocytes was studied. About 25 times more SRS-A activity was released from aliquots of leukocytes by ionophore stimulation than by antigen stimulation, although comparable amounts of histamine were released. Cell separation studies revealed that granulocytes other than basophils were also capable of releasing SRS-A. The contractile activity released after challenge with ionophore appeared physicochemically identical to the SRS-A of rat or human origin released by antigen challenge in terms of its stability to base hydrolysis, inactivation by arylsulfatase, and chromatographic behavior on silicic acid and Sephadex LH-20 columns. We suggest that some mediators of allergic reactions previously associated, in man, only with antigen-IgE antibody interaction on mast cells or basophils may be released by other stimuli and from other cell types.

The effects of H1 and H2 receptor anatagonists on models of allergic reactions in monkey skin have been studied. Intradermal histamine is markedly inhibited by H1 receptor antagonists but not by H2 receptor antagonists in the doses used. However, the combination of both receptor antagonists gives greater inhibition than that seen with H1 receptor blockade alone. Reverse-type anaphylaxis is also markedly inhibited by H1 but not H2 receptor antagonists. Passive cutaneous anaphylaxis (PCA) is likewise inhibited by H1 receptor antagonism, but not by H2 receptor antagonism. The combination of the two inhibitors leads to a complete inhibition of this PCA response. The data suggest that the addition of an H2 receptor antagonist may potentiate the effect of H1 blockade alone.

In some allergic sera, 2-hr PCA responses can be due to IgE class antibody. In other sera where 2-hr PCA responses are not seen, removal of the IgG fracton allows expression of this 2-hr latency PCA response, suggesting an initial competition for binding sites between IgG and IgE, or that IgG can act as a blocking antibody, preventing antigen from reaching the cell-bound IgE.

The antigen-induced release of slow-reacting substance of anaphylaxis was studied in rats previously treated with different biological and pharmacological agents to deplete these animals of specific cellular elements. The polymorphonuclear leukocyte appears necessary as a crucial cell type for optimum release of the slow-reacting substance of anaphylaxis, whereas the mast cell and lymphocyte are not required.

The polymorphonuclear leukocyte appears to be an essential cellular prerequisite for the antigen-induced release of SRS-A(rat) in the peritoneal cavity of rats prepared with homologous, hyperimmune antisera. Depletion of PMN leukocytes is associated with a marked suppression of SRS-A(rat) release, whereas depletion of circulating lymphocytes or peritoneal mast cells does not influence the antigen-induced release of SRS-A(rat). A local increase in the number of PMN leukocytes produced by the induction of a peritoneal exudate was associated with an enhanced release of SRS-A(rat). A distinct difference in the cellular requirements for the antigen-induced release of histamine and SRS-A(rat) in the rat was observed. Homocytotropic antibody-mediated histamine release could be achieved in leukopenic rats but not in mast cell-depleted animals. Conversely, SRS-A(rat) release was suppressed in leukopenic rats but was unaffected by mast cell depletion. Diethylcarbamazine inhibited the antigen-induced release of SRS-A(rat) following preparation with homologous, hyperimmune antisera but did not interfere with homocytotropic antibody-mediated histamine release. In preventing SRS-A(rat) release, diethylcarbamazine did not interfere with antigen-antibody interaction since desensitization of tissues was possible in the presence of this inhibitor. This observation is consistent with the view that diethylcarbamazine inhibits the reaction sequence leading to the formation and release of SRS-A(rat) at some step subsequent to antigen-antibody interaction. These studies support the view that the immunologic pathways leading to the release of SRS-A(rat) and histamine in the rat are distinctly different in terms of the immunoglobulins involved, the cellular prerequisites, and the effective pharmacologic inhibitors.

The immunologic release of histamine and slow reacting substance of anaphylaxis (SRS-A) from human lung tissue can be enhanced by stimulation with either alpha adrenergic agents (phenylephrine or norepinephrine in the presence of propranolol) or cholinergic agents (acetylcholine or Carbachol). The finding that atropine prevents cholinergic but not comparable alpha adrenergic enhancement is consistent with the view that cholinergic and alpha adrenergic agonists interact with separate receptor sites on the target cells involved in the immunologic release of chemical mediators. The consistent qualitative relationship between the antigen-induced release of mediators and the level of cyclic adenosine monophosphate (cyclic AMP) as measured by the isolation of (14)C-labeled cyclic AMP after incorporation of adenine-(14)C into the tissues or by the cyclic AMP binding protein assay suggests that changes in the level of this cyclic nucleotide mediate adrenergic modulation of the release of histamine and SRS-A. The addition of 8-bromo-cyclic guanosine monophosphate (cyclic GMP) produces an enhancement of the immunologic release of mediators while dibutyryl cyclic AMP is inhibitory. As cholinergic-induced enhancement was not associated with a measurable change in the levels of cyclic AMP, the possibility is suggested that cyclic GMP may be the intracellular mediator of cholinergic-induced enhancement of the immunologic release of histamine and SRS-A.

To demonstrate skeletal metastases before radiographic changes were apparent, Sr(85) scans were carried out on 46 patients who complained of sketetal pain but whose radiographs were negative. Positive scans were obtained in 34 patients, 20 of whom were subsequently shown to have metastases; three did not have skeletal metastases a year or more later; the outcome is unknown in 11 patients. Twelve patients had negative scans: three ultimately developed metastases, six did not, and three were inconclusive. Autoradiographs demonstrated Sr(85) concentrations in areas of reactive osteogenesis.Although not specific for skeletal metastases, Sr(85) scans are most helpful in substantiating this diagnosis when radiographic changes are absent.