Vernon L. Moore

A study of lung lavage materials in patients with hypersensitivity pneumonitis: in vitro response to mitogen and antigen in pigeon breeders' disease.

Abstract BAL fluids and cells were evaluated for cellular content and PHA- and antigen-induced proliferation in patients with the HP, PBD. Peripheral blood cells from these patients were also evaluated for mitogen- and antigen-induced proliferation as a comparison with lung lavage cells. The results indicate that BAL from patients with HP contained large proportions of lymphocytes which responded to PHA. However, several pigeon breeders without typical symptoms of PBD also had high proportions of lymphocytes in BAL and all lung lavage cells from these individuals responded to PHA as did peripheral blood cells from both patients with PBD and their asymptomatic cohorts. When BAL cells were stimulated with pigeon antigens, seven of eight patients with PBD displayed significant proliferation, whereas only two of nine asymptomatic pigeon breeders responded to antigen. Most patients with PBD (five of eight) had circulating lymphocytes which responded to pigeon antigens; however, five of nine asymptomatic pigeon breeders also had circulating lymphocytes which were stimulated by pigeon antigens. This study substantiates the fact that patients with PBD have high proportions of lymphocytes in their bronchoalveolar cells and shows that they respond to PHA, a predominantly T cell mitogen. However, some asymptomatic pigeon breeders also have large proportions of lymphocytes in their BAL fluid which react with PHA; the significance of this finding is not known at the present time. The key finding of lymphocytes in BAL which react with pigeon antigens, usually not found in BAL of asymptomatic pigeon breeders, indicates that specifically activated T lymphocytes are present in the lung parenchyma and suggests that they participate in the pathogenesis of the disease.

Cell-Mediated Hypersensitivity in Pigeon Breeders

This investigation was carried out to study possible differences in cell-mediated hypersensitivity between symptomatic and asymptomatic pigeon breeders. A variety of pigeon antigens were investigated using the indirect migration inhibition test. Cell-mediated hypersensitivity to pigeon antigens was detected in 6 of 8 symptomatic pigeon breeders, and in only 2 of 12 asymptomatic pigeon breeders. The results suggest that cellular mechanisms may be important in the pathogenesis of pigeon breeders disease.

Role of angiotensin-converting enzyme in Bacille Calmette-Guérin-induced granulomatous inflammation. Increased angiotensin-converting enzyme levels in lung lavage and suppression of inflammation with captopril.

Lung lavage levels of angiotensin-converting enzyme (ACE)-like activity were increased in C57BL/6 mice with Bacille Calmette-Guérin (BCG)-induced chronic granulomatous pulmonary inflammation and splenomegaly. Contrariwise, ACE activity was not increased in lung lavage fluids of CBA mice that developed only minimal pulmonary inflammation in response to BCG. ACE-like activity correlated with the intensity of inflammation and Captopril, a specific competitive inhibitor of ACE activity, markedly suppressed the induction and maintenance of the BCG-induced inflammatory response in both lungs and spleen. It was necessary, however, to provide sustained treatment with large doses of Captopril in order to reduce the inflammatory response. After a single intraperitoneal injection of Captopril, ACE levels in lung lavage of BCG-injected mice were reduced but returned to preinjection levels or greater within 24 h. The highest dose of Captopril was more effective in reducing the lung fluid level of ACE in BCG-inflamed lungs. This suggests that sustained daily injections of Captopril were necessary to maintain reduced ACE levels. In vitro studies indicated that high concentrations of Captopril did not affect macrophage mobility or chemotactic activity for macrophages. Thus, ACE may act as a molecular mediator of BCG-induced granulomatous inflammation in the lung.

An animal model of hypersensitivity pneumonitis in the rabbit.

This study was devised to produce an animal model of hypersensitivity pneumonitis in order to study both the induction and the elicitation of the disease. Rabbits exposed by aerosol to large quantities of pigeon antigens developed a humoral, but not cellular, immunologic response. Moreover, their lungs were essentially normal histologically. A single i.v. injection of killed BCG in oil permitted the induction of pulmonary cell-medid hypersensitivity to the inhaled antigen, as well as the development of pulmonary lesions which were more severe than that caused by the administration of BCG alone. The humoral immunologic response to the inhaled antigen was not increased after BCG injection. Since many individuals are exposed to the etiologic agents of hypersensitivity pneumonitis for extended periods without developing the disease, these findings in animals suggest that some event may occur to induce cell mediated hypersensitivity in order to initiate the disease process. In addition, we have shown that animals with normal lung histology and circulating complement-fixing antibodies undergo serum complement (CH50) depression after an aerosol challenge with the specific antigen. Animals with circulating, complement-fixing antibodies, and inflamed lungs (BCG-induced failed to undergo a complement depression subsequent to an aerosol challenge with specific antigens. These results re consistent with those seen in symptomatic and asymptomatic pigeon breeders and suggest that antigen distribution through the lung is important in the pathogenesis of hypersensitivity pneumonitis.

Humoral and cellular immune responses in Aspergillus fumigatus pulmonary disease

This study was designed to evaluate immunologic differences between aspergilloma (A) and allergic bronchopulmonary aspergillosis (ABPA), comparing the results to atopic and nonatopic control subjects. Humoral studies included skin tests with common inhalant antigens and Aspergillus fumigatus. Total and specific IgE and other immunologlobulin levels and serum precipitins were evaluated against A. fumigatus. Cellular immunity was studied with routine skin testing and phytohemaqglutinin-induced lymphocyte blast transformation. Antigen-induced blast transformation was also carried out with the use of serial dilutions of A. fumigatus. All patients with ABPA were atopic and had marked elevations of IgE. None of the patients were atopic and they had normal IgE levels. Immediate and late skin reactivity to A. fumigatus was low in control and A groups but high in 2 patients with ABPA. IgG antibody against A. fumigatus was generally greater in the ABPA group. Both ABPA and A had serum precipitating antibody against A. fumigatus. The atopic controls had elevated IgE levels and immediate skin test reactivity to A. fumigatus, and one also had weak serum precipitins against A. fumigatus. IgE antibody against A. fumigatus was generally higher in ABPA than A. ABPA and A patients had elevated stimulation indices (SI) to A. fumigatus. No stimulation could be detected with cells from control subjects. This study indicates that both T and B cell sensitization may play a role in the development of or as a response to aspergillus-related pulmonary disease.

Immune-complex disease in guinea pig lungs: I. Elicitation by aerosol challenge, suppression with cobra venom factor, and passive transfer with serum☆

Abstract Immune-complex disease was elicited in the lungs of ovalbumin-sensitized guinea pigs following an aerosol challenge with specific antigen. An acute inflammatory reaction, characterized by peribronchial polymorphonuclear leukocyte infiltration, edema, and hemorrhage, was observed 2 hr following aerosol challenge. This focal reaction developed into a diffuse reaction within 6 to 12 hr postchallenge. By 24 hr postchallenge, the acute inflammatory process had begun to resolve. The active disease was suppressed with cobra venom factor and was transferred to normal guinea pigs with immune serum.

Absorption of inhaled antigen into the circulation of isolated lungs from normal and immunized rabbits.

The purpose of this study was to determine whether the absorption of inhaled antigen (Ag) across the pulmonary air-blood barrier of the isolated perfused lung can be modulated by immunologic mechanisms. Lungs from immunized or nonimmunized rabbits were removed, ventilated, and perfused with autochthonous blood. Radioiodinated Ag (human serum albumin or ovalbumin) was introduced as an aerosol into the isolated lung for 15 min and blood samples were taken over a 4-h period. The results showed that radioactivity fom inhaled Ag entered the perfusing blood as two fractions. One fraction was precipitable by 5% trichloroacetic acid or antiserum. The TCA-soluble fraction chromatographed differently from iodide and may have represented metabolites of the Ag. Immunization specifically reduced the amount of antigenically intact protein entering the blood. On the other hand, the metabolite reached higher concentrations in the blood of immunized lungs. We conclude that the alveolar capillary barrier of the normal rabbit lung could provide a significant route of entry for inhaled antigen into the systemic circulation and that immunization reduces absorption via this route and enhances pulmonary metabolism of the Ag.

Pigeon breeder's disease. II. Pigeon antigen induced proliferation of lymphocytes from symptomatic and asymptomatic subjects

Lymphocyte reactivity to pigeon antigens was demonstrated in a patient with severe symptomatic pigeon breeders disease (PBD). The reactivity of the lymphocytes declined subsequent to cessation of exposure to antigen and in parallel with clinical improvement. Lymphocyte reactivity was also demonstrated in another patient with PBD, in a pigeon breeder with no evidence of PBD, and in a laboratory investigator with a history of exposure to birds other than pigeons. Lymphocyte reactivity in the latter subject increased following cutaneous injection of pigeon serum with the development of delayed‐type cutaneous reactivity. Although lymphocyte reactivity to pigeon antigens may be a necessary immunologic feature for production of PBD, this reactivity does not occur only in symptomatic subjects.

BCG-induced macrophage suppression in mice: Suppression of specific and nonspecific antibody-medicated and cellular immunologic responses

Abstract The intravenous injection of killed BCG in an oil-in-saline emulsion (BCG-E) results in the development of intense chronic granulomatous inflammation in the lungs and spleen of C57B1/6 (B6) but not CBA mice. B6 mice injected intravenously with BCG-E exhibited marked suppression of antibody responsiveness and delayed hypersensitivity to sheep erythrocytes, as well as proliferation in response to PPD. In contrast, CBA mice similarly treated with BCG-E were not suppressed in any of these reactivities. The spleen is an important organ in this phenomenon since suppression was reversed by splenectomy and could be transferred to normal recipients with spleen cells from BCG-treated mice. Spleen cells responsible for suppression were adherent to plastic petri plates, removed with carbonyl iron, and were not eliminated with either anti-Thy-1 or anti-immunoglobulin serum + C. This study indicates that macrophages from BCG-inflamed spleen are capable of potent suppression of both antibody- and cellular-mediated immunologic reactivity.

The effect of immunization on the uptake of intratracheally administered antigen.

Abstract The purpose of this study in rabbits was to evaluate the effect of immunization on the uptake of intratracheally administered 125I-labeled ovalbumin (OA) into the circulation. Immunization reduced the amount of trichloroacetic acid-precipitible antigen entering the circulation: this suppression of antigen uptake did not appear to be due to increased systemic clearance of immune complexes. The reduction of antigen appearance in the blood could largely be accounted for by factors in serum, presumably antibodies, since the reaction was immunologically specific and was transferrable to normal recipients with immune serum. The rate of antigen uptake into the blood, expressed as an appearance velocity, was reduced approximately four-fold in immunized animals compared to normal animals. In addition to reducing the uptake of OA through the lung, immunization also appeared to cause greater catabolism of the antigen in the lung.