Correlation between cytotoxic and suppressor activities of human pulmonary alveolar macrophages.

We have reported previously that pulmonary alveolar macrophages (PAMs) from individuals with lung cancer and active chronic pulmonary diseases were cytotoxic to tumor cells in vitro, whereas PAMs from normal individuals or patients with acute pulmonary disorders were noncytotoxic. In the present study, we evaluated 20 PAM preparations for both suppressor and cytotoxic functions to determine if PAMs could function as suppressor cells and, if so, whether a correlation between the two functions exists. Cytotoxicity was assessed in a 60-hr cytotoxicity assay against [3H]proline-prelabeled human melanoma target cells. More than 20% cytotoxicity was considered to be significant. Suppressor activity was measured by determining whether admixing PAMs at various ratios with autologous or allogeneic mononuclear cells could suppress concanavalin A-induced blastogenesis by T-lymphocytes. At least 50% suppression was considered to be significant. Of the 20 specimens evaluated, 13 were cytotoxic and 5 of these exhibited suppressor activity. None of the 7 noncytotoxic PAM preparations had suppressor activity. Suppression was nonspecific and not HLA restricted, since autologous and allogeneic mononuclear cells were inhibited to a similar extent. Suppression was probably not due to prostaglandin production by the PAMs since assays were performed under optimal conditions and required extremely high concentrations of prostaglandins. A significant correlation between suppressor and cytotoxic activity was found. Suppression was observed only with PAM specimens that were also highly cytotoxic to tumors, but not all cytotoxic PAM specimens were suppressive. Whether these actions reflect different levels of activation of PAMs or are the properties of different macrophage subsets remains to be clarified.

Acute eosinophilic pulmonary disease associated with the ingestion of L-tryptophan-containing products.

A series of four patients with pulmonary infiltrates, pleural effusions, hypoxemia, peripheral eosinophilia, and symptoms of dyspnea, fatigue, and weakness is reported. Lung tissue obtained in three patients revealed interstitial pneumonitis, small-to-medium-vessel mixed-cell vasculitis, and alveolar exudate of histiocytes and eosinophils. All patients reported ingestion of L-tryptophan-containing products at a time when an association between L-tryptophan and the eosinophilia-myalgia syndrome was established. This clinical pattern of pulmonary involvement may be part of the continuum of the eosinophilia-myalgia syndrome. The pathophysiology of this syndrome and the relationship with the ingestion of L-tryptophan-containing products have not yet been identified.

Safety of fiberoptic bronchoalveolar lavage in evaluation of interstitial lung disease.

Over a three-year period, 281 fiberoptic bronchoalveolar lavage procedures were performed on 119 individuals with interstitial lung disease and 22 normal volunteers. There were no major complications. Less than 5 percent of the procedures were associated with minor complications including (2.5 percent), pneumonitis (0.4 percent), bleeding (0.7 percent) and bronchospasm (0.7 percent); none of these complications required therapy. Those individuals developing complications had a wide range of physiologic findings; functional tests could not predict which subjects were more likely to develop minor complications associated with lavage. These findings suggest that bronchoalveolar lavage for interstitial disease is a safe procedure associated with minor risks.

Re-evaluation of sputum staining for the diagnosis of pulmonary tuberculosis.

Data were collected at 2 teaching institutions, University Hospital, University of Michigan (UMH) and University of California at Los Angeles (UCLA) Hospital, to evaluate the usefulness of the auramine-rhodamine fluorochrome stain in the diagnosis of pulmonary tuberculosis in hospitalized patients. The patients studied had received no prior therapy, and their sputum specimens were positive for a pathogenic Mycobacterium by microscopy or culture or both. The true-positive smear rate was 0.88 at UMH and 0.83 at UCLA; the relative false-positive smear rate was 0.12 at UMH and 0.17 at UCLA. The sensitivities at UMH and UCLA were 0.78 and 0.51, respectively, and the specificity was greater than 0.99 at both. The data suggest that sputum stained by the fluorochrome method is useful and reliable for the diagnosis of pulmonary tuberculosis, because the false-positive rates are acceptably low in hospitalized patients.

The reliability of gastric smears by auramine-rhodamine staining technique for the diagnosis of tuberculosis.

From 1972 to 1974, all sputum specimens and gastric aspirate specimens submitted to the University of Michigan Laboratory for acid-fast smear and culture were studied. Specimens were paired for culture and smear results using the auramine-rhodamine staining technique. Of 1,893 patients, 75 patients without prior antituberculous therapy were found to have either a positive smear or a positive culture of either sputum or gastric material. The data analyzed by patient source revealed the following. (1) Staining sputum with auramine-rhodamine is a clinically reliable technique for detecting pulmonary tuberculosis. It demonstrates a sensitivity of 78 per cent and a relative fraction of false positive smears of only 11 per cent. (2) Staining gastric-aspirated material by the auramine-rhodamine technique is not a clinically reliable method as a routine procedure for the detection of pulmonary tuberculosis, because of a sensitivity of only 58.8 per cent and a relative fraction of false-positive smears of 33 per cent. (3) In the absence of sputum in suspected clinical granulomatous disease, quantified gastric smears may be helpful. In this study, when more than 6 organisms per high power field were found, the patient's sputum or gastric material yielded a pathogenic mycobacterium on culture.

Biorhythm theory and asthma.

The hypothesis that bronchial asthma might follow a biorhythmic pattern was tested in 25 asthmatics with moderate to severe obstruction who completed daily diaries of respiratory symptoms and medication use. Biorhythm cycles (for 23-, 28- and 33-day periods) were calculated. Analysis of scores of medication use or respiratory symptomatology failed to demonstrate any relationship between asthma and biorhythm cycles or any other periodicity.

Flexible fiberoptic proctoscopy compared with fecal examination techniques for diagnosis of Prosthenorchis infection in squirrel monkeys (Saimiri sciureus).

Using flexible fiberoptic proctoscopy, diagnosis of Prosthenorchis infection in 17 squirrel monkeys (Saimiri sciureus) was correct 100% of the time. Fecal examination by formalin-ether sedimentation and sodium nitrate flotation were 68% and 10% diagnostically correct, respectively.

Flexible fiberoptic bronchoscopy of the rhesus monkey (Macaca mulatta).

Using a flexible fiberoptic bronchoscope, 10 rhesus monkeys were bronchoscoped 30 times without complication. The bronchoscopic anatomy was found to be similar to that of the human except for the presence of a right cardiac lobe in the monkey.