Immunologic lung disease

Aspergillus in the lung: diverse and coincident forms

Pulmonary disease caused by the fungus Aspergillus has traditionally been regarded as belonging to one of the following, apparently distinct, entities: saprophytic aspergilloma; allergic bronchopulmonary aspergillosis (ABPA); and invasive aspergillosis (IPA); which may be further categorised as angioinvasive, acute or chronic airway invasive) [1]. It is not always obvious that there is overlap between these entities, and that in any given patient more than one Aspergillus-related pathological process can co-exist [2]. The aim of this article is to review the clinical and imaging features of the main categories of Aspergillus-related pulmonary disease and, in particular, to highlight the overlap between them.

Agricultural lung disease

Agricultural work is associated with high rates of injury, disability, and illness. Agricultural workers are at increased risk for a variety of illnesses including respiratory disorders, dermatologic conditions, and cancer. The recognition of ODTS led to increased understanding of acute illness in farmers and grain workers. Previously, many cases of acute illness were probably erroneously called farmer's lung. The same agents that are responsible for ODTS are responsible for the high prevalence of bronchitis in certain agricultural workers. The recent description of the innate immune system is very exciting because it will lead to increased understanding of the pathogenesis of organic dust induced disorders.

Electron microscopic study of chronic eosinophilic pneumonia

Two cases of chronic eosinophilic pneumonia were examined electron microscopically to study the role of eosinophil granulocytes. Eosinophils, together with macrophages and lymphocytes, were observed to have infiltrated prominently in the lung tissues of the two cases. Degeneration and necrosis of pneumocytes were observed, and denuded basement membranes and destroyed alveolar structures were occasionally found. In the alveolar septa, swelling of the endothelial cells of the blood capillaries, edema of the stroma and fibrin deposition were observed. Eosinophils, released eosinophil granules and macrophages phagocytosing eosinophil granules were found frequently near the degenerated and necrotic alveolar tissues. These findings suggest that the tissue injuries were induced by the cytotoxic effects of the eosinophil granules.

Aspergillosis: a disease with many faces

Aspergillus causes a variety of pulmonary diseases. For the most part, they can be divided into three groups: mycetoma, invasive aspergillosis, and allergic forms of aspergillosis. The mycetoma form of aspergillosis has no effective treatment other than surgery, which is reserved for the severely symptomatic patient, usually with massive hemoptysis. Invasive aspergillosis is a dangerous pulmonary infection seen in patients who are generally severely immunocompromised. It is treated with amphotericin B and success in treatment of this form of aspergillosis is limited. Two of the allergic forms of Aspergillus infection, allergic bronchopulmonary aspergillosis and bronchocentric granulomatosis, are treated with steroids. The third allergic type of reaction, hypersensitivity lung, is best treated by removal of the patient from exposure to the antigen. Although these are the characteristic forms of aspergillosis, there is occasional overlap of the different types of aspergillosis.

Chloroquine treatment of interstitial lung disease in children

Seven children aged 3 months to 11 years with histologically confirmed interstitial lung disease (ILD) [6 with desquamative interstitial pneumonitis (DIP) and 1 with chronic interstitial pneumonitis] were treated with chloroquine, 10 mg/kg/day. One patient, diagnosed late in the course of the disease, died after three weeks of treatment, despite the addition of systemic corticosteroids. Another patient responded to combined therapy with chloroquine and prednisone and had a normal lung biopsy after 6 months of treatment. He underwent surgical repair of mitral valve stenosis and died after extensive brain infarction. The other 5 patients responded well to chloroquine therapy with major improvement in oxygenation within a few weeks and in lung function over the next few months. They remained well clinically and physiologically, including a normal response to incremental exercise, during a mean follow-up period of 9.8 years (range 3.5 to 15.7 years). None of the patients has developed retinopathy or any other ocular complication. Bronchoalveolar lavage was a useful tool for evaluation of the activity of the disease (predominance of neutrophils) in 3 out of 4 patients. We suggest that chloroquine should be considered as an effective treatment in ILD in children. Incremental exercise test may be helpful for routine follow-up and evaluation of the efficacy of a specific treatment.

An 8-year follow-up study of pulmonary function in patients with rheumatoid arthritis

To evaluate longitudinal alterations in pulmonary function, 63 patients suffering from rheumatoid arthritis (RA) with previously reported reduced pulmonary diffusing capacity were re-examined in an 8-year follow-up study. Cross-sectional examination revealed normal values for vital capacity (VC), forced expiratory volume in 1 s (FEV1) and diffusing capacity per litre alveolar volume (KCO). Total diffusing capacity (DLCO; P < 0.0001), maximal expiratory flow at 75% of expired VC (MEF75; P < 0.0001) and MEF50 (P < 0.01) were decreased. Longitudinal evaluation revealed unchanged MEF50, MEF75 and FEV1, whereas increases in DLCO (P < 0.0001) and KCO (P < 0.0001) and a decrease in VC (P < 0.05) were found. The longitudinal changes in diffusing capacity were unrelated to patient age, disease duration, disease activity in the study period or pulmonary function at the first examination. Thus, in patients suffering from RA, the most prominent functional pulmonary abnormality, decreased diffusing capacity, appeared to improve in the course of time, despite a slight decrease in VC and continued articular disease activity.

Air pollution: the pathobiologic issues

In defining the adverse effects of ambient levels of ozone on the human lung, research has tended to emphasize direct cause and effect responses. However, disease is generally multicausative and the lung has relatively few ways to respond to injury. Moreover, all adult lungs have some disease. Thus, pathogenesis is more appropriately addressed by asking "What role does the agent in question play in the causation, promotion, facilitation, and/or exacerbation of disease that is present?" Our recent studies of the lungs of 107 ostensibly healthy youths between 14 and 25 years of age (violent death cases in Los Angeles County) add suggestive evidence to epidemiologic and experimental data indicating that air pollution is adversely affecting the human lung. We found 80% of the youths with some degree of presumably subclinical Centriacinar Region disease and, in 27%, the Centriacinar Region disease was severe and extensive. Centriacinar Region disease has been linked to infectious organisms, cigarette smoke, ozone, mineral dusts, and other noxious agents. Recently, a mild form of Centriacinar Region disease has been produced in primates exposed to a level of ozone (0.15 ppm) that is frequently exceeded in Los Angeles. Since there is suggestive evidence that air pollution in Los Angeles increases the rate of decline of lung function, we suspect that there has also been an increase in the rate of structural decline, manifest in part by accentuated Centriacinar Region disease. The health significance of Centriacinar Region disease is just beginning to be appreciated. At the very least, reserve depletion reflected in the Centriacinar Region disease implies some reduction in lung performance and some increase in susceptibility to disease in general. At worst, the unexpected severity of the Centriacinar Region disease may be a bellwether for an impending rise in clinically manifested lung disease for the general population. An urgent research need is the monitoring of health through inventories of the functional and structural units of the human lung, with special emphasis on subpopulations of cell societies of the lung. The feasibility of applying image analysis for large volume objective quantitations has been demonstrated and should be implemented. Multicity studies, in cooperation with Offices of the Medical Examiner-Coroner and autopsy services in general, can help meet the critical need for increased sensitivity in the monitoring of the public health in a changing environment.

Sequential pulmonary function measurements during treatment of infantile chronic interstitial pneumonitis

Three infants with histologically confirmed chronic interstitial pneumonitis were treated with monthly intravenously administered high doses of methylprednisolone with or without daily hydroxychloroquine therapy. We applied the multiple occlusion technique to measure the static respiratory system compliance, and the end-inspiratory occlusion technique to measure passive respiratory system compliance, resistance, and time constant. When assessed by clinical criteria and pulmonary function measurements, all three patients showed improvement with this treatment. Clinical improvement was associated with an increase in respiratory system compliance as measured by both techniques (60% to 100% increase in all patients). The passive respiratory resistance and the time constant did not closely reflect the clinical course. We conclude (1) that high doses (pulses) of methylprednisolone and daily oral doses of hydroxychloroquine are effective in the treatment of infantile chronic interstitial pneumonitis and (2) that the respiratory system compliance, measured by both pulmonary function techniques, correlates well with the response to treatment and change in clinical status.

Increased local IgA production in chronic obstructive pulmonary disease

The immunoglobulin (Ig) content of serum and tracheal lavage fluid was measured in 50 horses suffering from chronic obstructive pulmonary disease (COPD) and 40 control horses. The mean immunoglobulin: albumin ratios of the lavage fluids of both groups were significantly higher than the corresponding values for serum, which indicates significant local production of immunoglobulins in the lower respiratory tract. The IgA: albumin ratio of lavage fluid was significantly higher in diseased compared with normal horses, which implies increased local production of IgA in this disease. The IgG: albumin and IgM: albumin ratios of lavage fluid were not significantly different in the two groups of horses. These results reveal an involvement of the respiratory mucosal immune system in COPD.

The varying manifestations of Aspergillus lung disease

The fungus Aspergillus may cause a variety of pulmonary disorders as a result of its ability to act as an allergen, as a simple saprophyte or as an infectious organism. The clinical manifestations range from hypersensitivity syndromes, in which corticosteroid therapy may be indicated, to disseminated infections, in which corticosteroid agents may be causative. The diagnosis may not be immediately apparent. Six cases are presented to illustrate the sometimes confusing manifestations of the disease.

Immunologic lung disease

The term "immunologic lung disease" comprises a broad spectrum of disease. I have covered a few entities in which recent studies have been particularly helpful in elucidating pathophysiology though not in uncovering the inciting cause. Common to all of these entities is the problem of finding appropriate methods of defining disease activity and response to treatment. As exemplified by the improved outlook for Goodpasture's syndrome with elucidation of its underlying immunopathology, it is likely that better understanding of the immunologic basis of sarcoid and interstitial disease may be helpful in planning more effective treatment strategies.

Usefulness of skin test in Farmer's lung

The skin test with hay extract or with Micropolyspora faeni (MF), is not commonly used in the diagnosis of Farmer's lung (FL), as it is not considered specific. In our study, we have applied the intracutaneous test with these antigens in 26 patients affected with FL; 18 of them were still in contact with the antigen and the remaining eight had not been in contact with the hay during the previous year. Twenty-five asymptomatic farmers (AF) served as a control group. In the first group and with hay extract, the immediate reading (I) was positive in 15 of 18 (83.3 percent), the late reaction (L) in 18 of 18 (100 percent), and the delayed one (D) in eight of 18 (44.4 percent). In the 25 AF, the results were as follows: I, seven of 85 (28 percent); L, 17 of 25 (68 percent); and D, one of 25 (4 percent). Consequently, the differences between both groups were significant: I, p less than 0.01; L, p less than 0.05; and D, p less than 0.01. Using MF as an antigen, the test is somewhat less effective: p less than 0.02, p less than 0.02, and p less than 0.2, respectively. These results suggest that the intradermal injection with hay extract is an easy, effective test in the diagnosis of FL, and at the same time, a better means of distinguishing FL patients from AF than the precipitation test.

Immunologic mechanisms in pulmonary disease

This article reviews some concepts about the organization of the immune system and the immunopathologic mechanisms of hypersensitivity. This is followed by a discussion of the effect of excessive or inappropriate immunologic resources on the respiratory tract.

Fatal desquamative interstitial pneumonia in three infants siblings

Desquamative interstitial pneumonia occurred in three siblings. Cough, difficulty in breathing, cyanosis, and failure to gain weight appeared during the first month of life; progressive hypoxia followed, and the three infants died in respiratory failure before the age of 4 months despite intensive drug and supportive treatment. The radiographic and the histologic appearance of pulmonary changes were similar in all three infants. Chest radiographs yielded normal findings initially, with rapid progression to a ground glass appearance of both lungs. Histologic findings of lung biopsies showed lymphoplasmocytic infiltration and fibrous thickening of the alveolar walls, swelling of alveolar lining cells, and large clumps of macrophages with PAS-positive foamy cytoplasm in the alveolar spaces.

Polymyositis and interstitial lung disease in a patient with anti-Jo1 prototype

The most common marker autoantibody among patients with polymyositis is anti-Jo1. The patient (John P.) providing the prototype serum for this specificity had both interstitial lung disease and polymyositis. A preliminary survey by Ouchterlony analysis and counter immunoelectrophoresis of serum from 15 patients with idiopathic interstitial lung disease revealed no anti-Jo1 or other precipitating autoantibodies. This provides no evidence to suggest that anti-Jo1 has specificity for interstitial lung disease per se. However, this autoantibody may serve as a possible marker for some patients with overlap of polymyositis and interstitial lung disease. The several interesting features about this patient's diseases and course are discussed.

Separation and characterization of lymphocytes from rat lung parenchyma

Rat pulmonary parenchymal tissue was disaggregated into a single cell suspension by treatment with collagenase. A cell population enriched for lung lymphocytes was separated by depletion of adherent cells on a Sephadex G-10 column: 16.7 +/- 2.7 X 10(6) cells per animal were recovered. On the basis of cytochemical and morphologic criteria, the separated cells contained greater than 80% lymphocytes, with a viability of 80-90%. The distribution of lymphocyte subpopulations was determined by indirect immunoperoxidase staining with appropriate monoclonal antibodies. Separated lung lymphocytes exhibited a proliferative response in vitro to phytohemagglutinin and concanavalin A. Supernatants from lung lymphocytes stimulated with concanavalin A contained lymphokine activity that could be demonstrated in a leukocyte procoagulant activity assay.

A new mutation, gld, that produces lymphoproliferation and autoimmunity in C3H/HeJ mice

A newly discovered autosomal recessive mutation, generalized lymphoproliferative disease (gld), in the C3H/HeJ strain of mice, determines the development of early onset massive lymphoid hyperplasia with autoimmunity. Significant lymph node enlargement is apparent as early as 12 wk of age. By 20 wk, lymph nodes are 50-fold heavier than those of coisogenic C3H/HeJ-+/+ mice. There is a concomitant increase in the numbers of peripheral blood lymphocytes. Analysis of C3H-gld lymph node lymphocyte subsets by immunofluorescence indicates an increase in numbers of B cells, T cells, and null (Thy-1-, sIg-) lymphocytes by 6-, 15-, and 33-fold compared with congeneic control mice. Serologically, gld/gld mice develop antinuclear antibodies (including anti-dsDNA), thymocyte-binding autoantibody, and hypergammaglobulinemia with major increases in several immunoglobulin isotypes. Mutant gld mice live only one-half as long as normal controls (12 and 23 mo, respectively). Interstitial pneumonitis was found in virtually all C3H-gld mice autopsied when moribund. Although immune complexes were detected in the glomerulus by immunofluorescence techniques, only 14% of the autopsied mice had significant lupus-like nephritis. Vascular disease was not found. The pattern of early onset massive lymph node enlargement, hypergammaglobulinemia, and production of antinuclear autoantibodies resembles the basic abnormal phenotype induced by the lpr (lymphoproliferation) mutation. The mutations gld and lpr are not allelic. Linkage studies indicate that gld is located between Pep-3 and Lp on chromosome 1. This new mutation adds another genetically well-defined model to the list of murine lymphoproliferative/autoimmune disorders that may be exploited to gain a clearer understanding of immunoregulatory defects and for identifying common pathogenetic factors involved in systemic autoimmune diseases.

Applications of electron microscopy to diagnostic pulmonary pathology

Viruses and other possible causative agents should be sought light and electron microscopically in all cases of ill-defined diseases including "sarcoid." Ideally, tissue should be prepared for electron microscopic examination as soon as a specimen is obtained; however, when this has not been done, tissue preserved in formalin solution can be used. Viruses, some bacteria, and other agents suspected on the basis of light microscopic findings can be verified electron microscopically by reprocessing paraffin-embedded tissue from areas that show smudge cells, focal necrosis with atypical cellular proliferation, and nuclear inclusions. Electron microscopically, all dying cells show swelling and rupture of cellular organelles and membranes; reactive changes include proliferation of branching tubules and paracrystalline and other types of proteinaceous precipitates (inclusions) in both the nucleus and cytoplasm. Qualitative and quantitative changes of cellular organelles, fibrils, microvilli, and intercellular junctions reflect hyperplasia, metaplasia, or dysplasia of the cell and may enable identification of the diseases, e.g., desquamative interstitial pneumonia. In various conditions, basal laminae become irregular, disruptive, or reduplicated following epithelial necrosis and regeneration. Electron microscopic evidence of immunologic damage to basal lamina and cells and immuno-electron-microscopic features of the lung in general require further studies. Electron microscopic features of transbronchial biopsy specimens may be diagnostic in cases of alveolar proteinosis, histiocytosis X, and amyloidosis. Ultrastructural abnormalities of cilia are common; primary ciliary defects are rare. Finally, light microscopic, scanning electron microscopic, and x-ray energy-dispersive spectrometric examinations of paraffin-embedded sections appear most practical for the pathologic evaluation of cases of pneumoconiosis.

Reaginic and non-reaginic antibodies against mammalian danders

Solid phase enzyme immunoassay (EIA) and passive haemagglutination techniques were used to study the occurrence of IgG-type antibodies against feline and bovine epithelial extracts among RAST-positive patients, senior veterinary students, cat fanciers (representing exposed subjects) and healthy controls. In most groups both techniques exhibited equal sensitivity being positive in about half of the RAST-positive cases. The levels of both EIA-reactive IgG-class and IgA-class antibodies were increased in most of the sera (greater than mean + 2 s.d. of controls), while only a few sera showed increased IgM values.

Effects of adrenalectomy and glucocorticosteroid therapy on bone marrow T cells. Effect on T cell traffic and graft-versus-host (GVH) reactivity

The effects of bilateral adrenalectomy (Ax) and glucocorticosteroid (GCS) treatment on the migratory behavior of circulating T cells in mice were evaluated by a 51Cr lymphocyte migration assay and two graft-versus-host (GVH) assays. The major new findings were that bilaterally adrenalectomizing a mouse effects it in two interrelated ways: 1) It decreases the accumulation of adoptively transferred 51Cr-labeled T cells to the bone marrow; and 2) it reduces the GVH reactivity of bone marrow cells. We also confirmed previous studies showing increases in the accumulation of T cells and increases in T cell-mediated GVH reactivity in the marrow of GCS-treated mice. We conclude that Ax has an opposite effect to that of GCS treatment on the intramarrow traffic of T cells and on T cell-mediated GVH reactivity of marrow cells.

Immunohistological study of human lungs by immunoperoxidase technique

An unlabelled antibody peroxidase-antiperoxidase method for the detection of IgG, IgM, complement (C3 and Clq), fibrinogen and albumin was applied to routinely processed paraffin sections of lung from 27 cases. The results in 11 cases were compared with those obtained by immunofluorescence using frozen sections. Tissue was obtained from surgical specimens of cases with interstitial pneumonia comprising 10 of the usual type (UIP) and three of the desquamative type (DIP). Tissue was also obtained from the specimens of cases with sarcoidosis (two cases) and granulomatous inflammation of unknown cause (one case). There were 11 control cases, nine with primary carcinoma of the lung and two with metastatic tumours of the lung. Immunoglobulins of various types and complement were seen in diseased lung tissue. Although most of these deposits were probably due to a non-immunological mechanism there was evidence of the possible implication of immune complexes in three cases of UIP and in the interstitial pneumonia present in the two cases of sarcoidosis. The immunoperoxidase technique is a more sensitive method than immunofluorescence and has the additional advantage of the easy identification of the precise sites of the various deposits.

Pulmonary function in patients with rheumatoid arthritis

106 women and 38 men suffering from definite or classical rheumatoid arthritis underwent a pulmonary function test. The results were correlated to the duration and various clinical activity parameters of the disease. Pulmonary diffusion capacity was found to be reduced compared with the predicted values (p less than 0.05), irrespective of the duration or activity of the disease. The findings suggest that inflammatory vascular changes in the lungs usually occur in rheumatoid arthritis even in cases where other extraarticular manifestations can usually not be demonstrated.

Antigen-specific densensitization in a rabbit model of acute hypersensitivity pneumonitis

Rabbits that had been prepared to develop acute alveolitis after aerosol challenge with simple protein antigens did not develop chronic alveolitis but rather gradually recovered despite continued challenge. Immunologic accompaniments of waning disease were compared in this model to those associated with intravenous injections of antigen causing "desensitization." We also studied the effects of aerosol challenge prior to systemic immunization, antigen specificity, and the duration of desensitization by aerosolized and intravenous antigen. We found that repeated aerosol or intravenous challenges produced antigen-specific desensitization in this model, and the effect lasted several weeks. Prior exposure to aerosolized antigen was not protective. Neither aerosol nor intravenous desensitization maneuvers abrogated antigen-specific lymphocyte blastogenesis, although an early transient fall did occur. Humoral responses were boosted. These findings suggest that chronic alveolitis is prevented in this model by specific desensitization, without the induction of true tolerance or of nonspecific anergy. Such immunoregulation may result from development of antigen-specific blockade or blocking factors (e.g., lymphokines), antigen-antibody complexes, or suppressor cells affecting specific effector cells. Evaluation of these mechanisms may have implications for diagnosis and prognosis in human hypersensitivity pneumonitis.

125I-Clq-binding and specific antibodies as indicators of pulmonary disease activity in cystic fibrosis

We studied the incidence and levels of circulating immune complexes by the 125I-Clq-binding assay in patients with cystic fibrosis in relation to clinical respiratory status and specific IgG and IgE antibodies to Pseudomonas aeruginosa. Staphylococcus aureus, Aspergillus fumigatus, and Candida albicans. Overall prevalence of CIC was 43%, but 86% of serially studied patients had evidence of CIC at some time. Patients with acute respiratory exacerbations and deteriorating pulmonary function had a higher incidence of CIC (76%) as compared to stable patients (36%, P less than 0.01), as well as significantly higher levels of CIC. Acute exacerbations were also associated with significant increases in IgG antibody to Pseudomonas (P less than 0.005) but not in other antibodies. CIC did not correlate with Pseudomonas-specific IgG nor with any other specific antibody studied. A variety of age-related differences in specific antibody levels were seen. The episodic appearance of CIC is common in CF and is usually associated with exacerbation of lung disease.

Mechanisms of tissue injury in desquamative interstitial pneumonitis

To evaluate a contribution of immunologic factors to the pathogenesis of desquamative interstitial pneumonitis (DIP), lung biopsy specimens from four patients were studied for immunoglobulin deposits in tissue and cellular characteristics by immunologic, ultrastructural and histochemical methods. Accumulations of large cells with vacuolated cytoplasm within the distal air spaces and marked increase in the numbers of type II pneumocytes lining pulmonary alveoli were observed in all cases. The cells in air spaces were identified as macrophages containing intracellular lysozyme and alpha-naphthyl acetate esterase. Deposits of immunoglobulin G(IgG) and the third component of complement were found in distal air spaces and on the surfaces of the accumulated macrophages. The interstitial fibrosis was not a significant feature in out patients. Circulating immune complexes and a decreased IgG level were detected in serum during the acute phase of the disease. IgG levels returned to normal and were no longer detectable during convalescence in one patient followed sequentially. The formation and deposition of complement-fixing antibody and/or immune complexes may be responsible for the local accumulation and activation of macrophages and for tissue damages. Release of lysosomal enzymes by alveolar macrophages phagocytosing the complexes could also contribute to the alveolar injury, whereas the proliferation of type II pneumocytes may be a reparative tissue reaction to immunologically-mediated injury.