Search

Presents a study which determined serum angiotensin-converting enzyme and lysozyme in granulomatous diseases of unknown cause. Method of the study; Results and discussion; Conclusion.

Background: The diagnosis of sarcoidosis is most secure when supported by a tissue biopsy exhibiting noncaseating epithelioid granulomas with absence of known granulomagenic agents in a patient with multi-organ disease. Clinicians must decide which site offers the best chance of achieving a diagnostic biopsy with the least patient risk and discomfort., Methods: 736 cases were enrolled in the NHLBI supported A Case Controlled Etiologic Study of Sarcoidosis (ACCESS) from November 1996 to June 1999. All cases required diagnostic organ biopsy (Bx) exhibiting non-caseating epithelioid granulomas without identifiable granulomagenic agent, within six months of recruitment. Positive Kveim-Siltzbach test was accepted in patients with Löfgren's syndrome. Bx sites were correlated with demographic data, chest radiographic stages, symptoms, pulmonary function and associated organ involvement., Results: Seven hundred and seventy-six diagnostic biopsies were performed. Five hundred and sixty-seven were intrathoracic, 198 extrathoracic. Eleven Kveim tests were positive. When cutaneous sarcoidosis or an enlarged extrathoracic lymph node was present, skin or lymph node Bx was the preferred procedure. Twenty-three different organs yielded diagnostic biopsies., Conclusions: Biopsy diagnosis in sarcoidosis is almost always easily obtained. As shown by ACCESS, sarcoidosis offers a wide spectrum of diagnostic biopsy sites. The choice for biopsy is influenced by the presenting clinical constellation of organ involvement and the ease and safety of the biopsy procedure.

Objectives: To determine whether specific occupations and industries may be associated with sarcoidosis., Methods: A Case Control Etiologic Study of Sarcoidosis (ACCESS) obtained occupational and environmental histories on 706 newly diagnosed sarcoidosis cases and matched controls. We used Standard Industrial Classification (SIC) and Standard Occupational Classification (SOC) to assess occupational contributions to sarcoidosis risk., Results: Univariable analysis identified elevated risk of sarcoidosis for workers with industrial organic dust exposures, especially in Caucasian workers. Workers for suppliers of building materials, hardware, and gardening materials were at an increased risk of sarcoidosis as were educators. Work providing childcare was negatively associated with sarcoidosis risk. Jobs with metal dust or metal fume exposures were negatively associated with sarcoidosis risk, especially in Caucasian workers., Conclusions: In this study, we found that exposures in particular occupational settings may contribute to sarcoidosis risk.

Past research suggests that environmental factors may be associated with sarcoidosis risk. We conducted a case control study to test a priori hypotheses that environmental and occupational exposures are associated with sarcoidosis. Ten centers recruited 706 newly diagnosed patients with sarcoidosis and an equal number of age-, race-, and sex-matched control subjects. Interviewers administered questionnaires containing questions regarding occupational and nonoccupational exposures that we assessed in univariable and multivariable analyses. We observed positive associations between sarcoidosis and specific occupations (e.g., agricultural employment, odds ratio [OR] 1.46, confidence interval [CI] 1.13-1.89), exposures (e.g., insecticides at work, OR 1.52, CI 1.14-2.04, and work environments with mold/mildew exposures [environments with possible exposures to microbial bioaerosols], OR 1.61, CI 1.13-2.31). A history of ever smoking cigarettes was less frequent among cases than control subjects (OR 0.62, CI 0.50-0.77). In multivariable modeling, we observed elevated ORs for work in areas with musty odors (OR 1.62, CI 1.24-2.11) and with occupational exposure to insecticides (OR 1.61, CI 1.13-2.28), and a decreased OR related to ever smoking cigarettes (OR 0.65, CI 0.51-0.82). The study did not identify a single, predominant cause of sarcoidosis. We identified several exposures associated with sarcoidosis risk, including insecticides, agricultural employment, and microbial bioaerosols.

To determine relationships among social predictors and sarcoidosis severity at presentation, demographic characteristics, socioeconomic status, and barriers to care, A Case-Control Etiologic Study of Sarcoidosis (ACCESS) was set up. Patients self-reported themselves to be Black or White and were tissue-confirmed incident cases aged > or =l8-yrs-old (n=696) who had received uniform assessment procedures within one of 10 medical centres and were studied using standardised questionnaires and physical, radiographical, and pulmonary function tests. Severity was measured by objective disease indicators, subjective measures of dyspnoea and short form-36 subindices. The results of the study showed that lower income, the absence of private or Medicare health insurance, and other barriers to care were associated with sarcoidosis severity at presentation, as were race, sex, and age. Blacks were more likely to have severe disease by objective measures, while women were more likely than males to report subjective measures of severity. Older individuals were more likely to have severe disease by both measures. In conclusion, it was found that low income and other financial barriers to care are significantly associated with sarcoidosis severity at presentation even after adjusting for demographic characteristics of race, sex, and age.

A cohort of 215 sarcoidosis patients from the ACCESS study underwent a clinical evaluation at study enrollment and two years later. Approximately 80% of subjects had an improved or stable FVC, FEV1, chest radiograph determined by Scadding stage, and dyspnea scale. African-Americans had less improvement in FVC than Caucasians (p = 0.04). Patients with erythema nodosum at presentation were more likely to have improvement in the chest radiograph at two-year follow-up (p = 0.007). Patients with a lower annual family income were more likely to worsen with respect to dyspnea (p = 0.01) and more likely to have new organ involvement at two-year follow-up (p = 0.045). The development of new organ involvement over the two year follow-up period was more common in African-Americans compared to Caucasians (p = 0.002) and more likely in those with extrapulmonary involvement at study entry (p = 0.003). There was an excellent concordance between changes in FVC and FEV1 over the two-year period. However, changes in FVC alone were inadequate to describe the change in pulmonary status of the patients, as changes in chest radiographic findings or the level of dyspnea did often but not always move in the same direction as FVC. In conclusion, data from this heterogeneous United States sarcoidosis population indicate that sarcoidosis tends to improve or remain stable over two years in the majority of patients. Several factors associated with improved or worse outcome over two years were identified.

Background and Aim of Work: It has been known for years that pathological changes of bronchiectasis may be seen on tissue examination of the lungs in pulmonary sarcoidosis. However, the clinical picture that may develop as a result of these changes has been under-appreciated., Methods: We report seven patients with advanced stage IV pulmonary sarcoidosis in whom clinical bronchiectasis developed, seen in our university based pulmonary clinic between 1978 and 1999., Results: These patients frequently exhibited symptoms and signs that are uncommon in sarcoidosis - hemoptysis, recurrent infection, lung crackles and digital clubbing. The clinical course was worse than similar stage nonbronchiectatic sarcoidosis, with more frequent infections and a higher mortality rate., Conclusions: Recognition of this subset of patients may improve management when complications arise. Therapy directed at bronchiectasis rather than aimed at suppressing putative continued sarcoidosis activity appears to be more important at this late stage of disease.

Sarcoidosis may be affected by sex, race, and age. A Case Control Etiologic Study of Sarcoidosis (ACCESS) enrolled 736 patients with sarcoidosis within 6 mo of diagnosis from 10 clinical centers in the United States. Using the ACCESS sarcoidosis assessment system, we determined organ involvement for the whole group and for subgroups differentiated by sex, race, and age (less than 40 yr or 40 yr and older). The study population was heterogeneous in terms of race (53% white, 44% black), sex (64% female, 36% male), and age (46% < 40 yr old, 54% > or = 40 yr old). Women were more likely to have eye and neurologic involvement (chi(2) = 4.74, p < 0.05 and chi(2) = 4.60, p < 0.05 respectively), have erythema nodosum (chi(2) = 7.28, p < 0.01), and to be age 40 yr or over (chi(2) = 6.07, p < 0.02) whereas men were more likely to be hypercalcemic (chi(2) = 7.38, p < 0.01). Black subjects were more likely to have skin involvement other than erythema nodosum (chi(2) = 5.47, p < 0.05), and eye (chi(2) = 13.8, p < 0.0001), liver (chi(2) = 23.3, p < 0.0001), bone marrow (chi(2) = 18.8, p < 0.001), and extrathoracic lymph node involvement (chi(2) = 7.21, p < 0.01). We conclude that the initial presentation of sarcoidosis is related to sex, race, and age.

Several chronic diseases are more severe in persons who are Black, of low socioeconomic status (SES), and underinsured. The authors ask if this is true for sarcoidosis. Associations among sarcoidosis disease severity, SES, insurance coverage, and functional limitations were analysed. Back and White sarcoidosis patients (n=110) of a municipal and university hospital sarcoidosis registry were interviewed by telephone. Data on disease severity were abstracted from patient charts. Most patients reported good or excellent health by demographic characteristics. Low SES and no or public insurance were associated with worse health status and more severe dyspnoea. More advanced radiographic stage was associated with lower income, and forced vital capacity impairment with less education. Physical and social activity limitations due to physical and emotional disability were related to no or public insurance and lower income, but not education. Sarcoidosis severity is associated with socioeconomic status and insurance indicators; no or public insurance and low income are associated with functional limitations. Sarcoidosis-associated limitations are substantial, emphasizing the social significance of sarcoidosis. Lack of private insurance may inhibit the use of medical care, contributing to disease severity and impairment.

Sarcoidosis, a chronic, multisystem disease, impacts quality of life and may increase depression risk. No previous study has reported the depression prevalence among U.S. sarcoid patients. This cross-sectional study examined sociodemographic and disease morbidity factors associated with depression. Patients diagnosed for > or = 1 yr and treated at one of six centers were eligible (n = 176); 154 completed a questionnaire of demographics, treatment, access to medical care, and a short-form Center for Epidemiologic Studies- Depression Scale (CES-D). The primary outcome variable was a CES-D score of > or = 9, indicating clinical depression. The prevalence of depression was 60%. Gender, income, access to medical care, dyspnea on exertion, and number of systems involved were associated with depression. Female sex, decreased access to medical care, and increased dyspnea predicted depression (odds ratio [OR] = 3.33, 11.64, and 2.78, respectively) after adjusting for race, income, and steroid therapy. Despite tertiary care access, patients reported medical care limitation. Health care providers must be sensitive to multiple barriers faced by chronic sarcoid patients; acknowledging depression risk and improving access to medical care will promote better overall health among sarcoid patients. Future studies of sarcoidosis will need to address depression diagnosis and treatment.

Charts and radiographs of sarcoidosis patients seen at a private university hospital and at a municipal hospital were reviewed to determine whether there was a difference in the severity of disease retrospectively. A standardized abstract form was used to identify and abstract information on new and continuing sarcoidosis patients seen at either Georgetown University Medical Center (GUMC) or District of Columbia General Hospital (DCGH) during a 2-year period. Because there were too few white sarcoidosis patients for comparison, analysis was done for African-American patients only. African-American patients at GUMC were slightly older, with a higher percentage of women. For GUMC patients, 76% had private insurance and 21% had public insurance, and for DCGH patients, one-half had public insurance and 29% had no insurance. Significantly fewer GUMC patients (7% versus 36%) reported moderate to severe dyspnea. Chest radiographs showed a larger percentage of patients with stage 1 disease at GUMC and more patients with stage 4 disease at DCGH. Spirometry showed more impairment of forced expired volume in one second (FEV1) in GUMC patients, but diffusing capacity of the lung for carbon monoxide (DLCO) values were significantly lower among DCGH patients. Less than 8% of GUMC patients showed disease progression compared with almost one-third of DCGH patients. These results demonstrate that substantially less severe pulmonary sarcoidosis was seen in African-American patients treated at a private, nonprofit university hospital compared with a municipal hospital. Factors that determine the use of municipal hospitals, such as limited financial access to care and sources of patients, may have played a major role in the differences seen.

Background: Sarcoidosis is a multiorgan granulomatous disease of unknown cause. Lack of an objective system for assessment of sarcoidosis to evaluate disease course and effectiveness of therapy is a major problem., Methods: The sarcoidosis assessment instrument was developed by the Steering Committee of A Case Control Etiologic Study of Sarcoidosis (ACCESS) which included investigators at the ten ACCESS Clinical Centers, the Clinical Coordinating Center, and representatives of the National Heart, Blood, and Lung Institute. This system was developed to assess sarcoidosis organ involvement in ACCESS patients who would be followed over a two-year period. The system represents a consensus of opinions of members of the Steering Committee based on review of their experience and the medical literature., Results: Criteria for involvement in patients with biopsy-confirmed sarcoidosis are presented for organs and systems that are commonly involved (lung, skin, eyes, liver, calcium metabolism), unusual but clinically important (nervous system, kidney, heart) and other sites (non-thoracic lymph nodes, bone marrow, spleen, bone/joint, ear/nose/throat, parotid/salivary glands, muscles)., Conclusion: The proposed instrument is partially subjective in that it depends upon the clinician's diligence in pursuing evidence for sarcoidosis involvement of various organs. It is hoped that this instrument will lead to increased standardization in the definition of sarcoidosis organ involvement to help clinicians and researchers better characterize patients with sarcoidosis.

In patients with acquired immunodeficiency syndrome (AIDS), mycobacterial diseases are leading opportunistic infections. The reasons for the peculiar propensity for disseminated infection with Mycobacterium avium complex (MAC) remain unclear. We have previously examined, in detail, the ability of monocytes from healthy donors to take up and kill MAC under both nonopsonic and opsonic conditions. We have now evaluated the in vitro ability of peripheral blood monocytes from HIV(+) patients to take up and kill MAC organisms, and have discovered a reduced ability under both nonopsonic and opsonic conditions. This reduction is due to: 1) apparent defect(s) in the phagocytes themselves, and 2) substance(s) in the HIV(+) serum which actively suppresses phagocyte activity.

CD44 glycoproteins are present on the surfaces of many hematopoietic cells and in some cases can bind hyaluronan, a major component of the extracellular matrix. In the present study, we have found that newly explanted human peripheral blood monocytes (PBMs) exhibit a major CD44 band of 85 kDa, whereas autologous alveolar macrophages (AM phi) express multiple isoforms ranging from 85 to 200 kDa. Within 4 h in culture, PBMs began expressing new CD44 isoforms of 120, 150, and 180 kDa. Newly explanted AM phi specifically bound [3H]hyaluronan (135 cpm/microgram protein), but newly explanted PBMs did not. However, in vitro cultured PBM progressively acquired the ability to bind [3H]hyaluronan and exhibited specific binding of hyaluronan similar to that of AM phi (113 cpm/microgram protein) after 4 days in culture. In both case, the binding of [3H]hyaluronan was specifically inhibited by the addition of monoclonal antibody directed against CD44. AM phi readily degraded [3H]hyaluronan and reached a plateau after 4 days in culture (115 cpm/microgram protein). Newly explanted PBM exhibit no hyaluronan degradation and only a small degradative activity after 4 days in culture (6 to 11 cpm/microgram protein). Thus, CD44 expression and function appear to change as PBM mature in vitro resembling more that found in AM phi.

To determine whether human alveolar macrophages (AM) generate a compound similar to the endothelium-derived relaxing factor, we studied the effect of AM on the isometric response of the pre-contracted rat aorta preparation in the presence and absence of L-arginine or N-substituted L-arginine compounds. Addition of AM to the pre-contracted aorta preparation was ineffective even in the presence of millimolar concentrations of L-arginine. But, AM in the presence of the substituted L-arginine, N alpha-benzoyl L-arginine ethyl ester, significantly increased vasodilation. The enhanced relaxation was associated with an increase in vascular cyclic guanosine 3,5'-monophosphate formation. Hemoglobin and N omega-nitro L-arginine methyl ester are inhibitors of the endothelium-dependent relaxation, and both attenuated the vasodilation elicited by AM. Human AM were found to metabolize N alpha-benzoyl L-arginine ethyl ester to a citrulline derivative. No such metabolism was observed with L-arginine. A specific, high-pressure liquid chromatographic assay for guanidines revealed that the lack of effect of external L-arginine is not due to the presence of an excess amount of endogenous L-arginine in AM. These results demonstrate that nonactivated human AM, unlike rodent macrophages, possess an enzyme system(s) that metabolize(s) arginine derivatives but not L-arginine to a vasodilator, and this vasodilator has properties similar to that of endothelium-derived relaxing factor. This human AM-derived vasodilator may have an important role in regulating airway smooth muscle function.

Two patients eventually shown to have empyema were encountered in which the initial thoracentesis revealed fluid compatible with either a simple or a complicated parapneumonic effusion. In both cases, the diagnosis of empyema was made by a second thoracentesis done at a close interval of time from a different site. Therefore, the physician should approach parapneumonic effusions systematically, and remember that in some cases, multiple thoracenteses may be required to make the correct diagnosis of an empyema.

The uptake of Mycobacterium avium complex (MAC) microorganisms by human peripheral blood monocytes (PBMs) and alveolar macrophages (AMs) is not well understood. We have previously shown, under opsonic conditions, that humoral factors are important in mediating the uptake of MAC by PBMs. However, the receptor-ligand interactions occurring under nonopsonic conditions remain unclear. We compared the uptake of untreated human PBMs and AMs in a serum-free medium with phagocytes treated to remove surface receptors. Removal of complement receptors CR1 and CR3, the Fc receptor (FcR), and the transferrin receptor (TfR) resulted in significantly lower levels of MAC uptake in serum-free medium by both PBMs and AMs. The addition of barley beta-glucan or mannan from Saccharomyces cerevisiae inhibited MAC uptake by untreated phagocytes in a dose-dependent manner. MAC uptake by PBMs or AMs was never completely abrogated by combining treatments (removal of CR1, CR3, FcR, and TfR and adding mannan or beta-glucan), indicating still-unknown mechanisms of uptake under nonopsonic conditions. We conclude that CR1, CR3, FcR, TfR, the mannose receptor, and possibly a separate beta-glucan-inhibitable receptor all may be involved in nonopsonic uptake of MAC by both PBMs and AMs.

Because interindividual variations in the activities of DNA repair enzymes may be a risk factor in the pathogenesis of lung diseases, O(6)-methylguanine-DNA methyltransferase (O(6)-MT) and uracil DNA glycosylase (UDG) were measured in broncho-alveolar lavage cell (BALC) and peripheral blood mononuclear cell (PBM) samples from 57 healthy volunteers (25 smokers and 32 non-smokers). According to cotinine determination in 39 cases where serum for this was available, 38% of the self-acclaimed non-smokers had greater than 10 ng/ml of cotinine in their serum. Whether grouped into smokers and non-smokers according to clinical history or by serum cotinine, there were no statistically significant differences between these groups in O(6)-MT or UDG in either of the cell types. However, a tendency towards lower values in smokers was seen. The highest intraindividual variation in O(6)-MT activity was 7-fold, while the highest interindividual variation reached 18-fold. For UDG, the respective values were 24- and 307-fold. Although the distribution of O(6)-MT in BALC was different from that in PBM, the data are consistent with unimodality in both of the cell types. These findings suggest that exposure to cigarette smoke is not entirely responsible for the wide interindividual variation in O(6)-MT and UDG DNA repair activities.

The role of inhaled aerosols in the treatment of obstructive airway diseases is increasing for both immediate bronchodilation and prophylactic anti-inflammatory effects. Inhaled aerosol agents are available in metered-dose inhaler and nebulizer forms. Maximum therapeutic benefit from metered-dose inhalers is assured when the correct inhaler technique is used. Spacer devices may be helpful in some patients.

Since the precise mechanism of host responses to infection with Mycobacterium-avium complex (MAC) is unclear and since cytotoxic lymphocytes may be involved in the destruction of cells infected with intracellular pathogens, we investigated the ability of normal peripheral blood lymphocytes to kill MAC-infected monocytes in a short-term isotope release assay. Nylon wool-passed lymphocytes lysed MAC-infected but not uninfected monocytes during a 4-hr assay. Infected monocytes were less sensitive to cell-mediated killing than the standard natural killer (NK) cell-sensitive cell line K562, although the kinetics of lysis were similar. The release of lymphocyte-derived mediators such as tumor necrosis factor, interleukin-2 (IL-2), and interferon-alpha and -gamma could not be implicated as a cause of monocyte death. Through the use of cell-specific monoclonal antibodies plus complement, the phenotype of the effector cell was that of an NK cell (CD3 negative, partially CD8 negative, and CD16 positive). The use of highly purified, negatively selected NK cells confirmed these results. NK cell-mediated lysis of infected monocytes decreased MAC viability, indicating that this cytotoxic activity would not favor dissemination of the organism. The killing of MAC-infected monocytes was reduced by K562 cells, suggesting that these targets shared common recognition/binding structures. These results suggest that NK-cell function may be important in the prevention of or response to MAC infection and may help explain the predilection of AIDS patients to develop widespread disease.

The effect of alveolar macrophages (AM) on pokeweed mitogen (PWM)-stimulated immunoglobulin (Ig) secretion by unfractionated and monocyte-depleted human peripheral blood mononuclear cells was studied. Responsiveness in monocyte-depleted peripheral blood mononuclear cell populations could be partially restored by addition of autologous monocytes and to a lesser extent with AM. Addition of AM to unfractionated peripheral blood mononuclear cells resulted in significant inhibition of Ig secretion, especially at high (5-10 micrograms/ml) doses of PWM. The degree of suppression was proportional to the number of AM present. On the other hand, addition of monocytes to similar unfractionated peripheral blood mononuclear cell cultures did not result in suppression of Ig secretion at any of the doses of PWM used. Suppression by AM was not attributable to an alteration of response kinetics. The results demonstrate that mononuclear phagocytic cells are necessary for activation of polyclonal Ig secretion by human B cells and that AM are capable of suppressing this response.

Nontuberculous mycobacteria are identified in almost half of the cultures reported positive for mycobacteria in clinical laboratories in the United States. While many represent saprophytic colonization or laboratory contamination, a significant number of these organisms are the agents of disease. Such organisms can be the cause of pulmonary, soft tissue, cutaneous and lymphatic infections, keratitis, osteomyelitis, postsurgical infection, endocarditis and disseminated disease.

Replicative cultures of human pleural mesothelial cells were established from noncancerous adult donors. The cells exhibited normal mesothelial cell characteristics including keratin, hyaluronic acid mucin, and long branched microvilli, and they retained the normal human karyotype until senescence. The mesothelial cells were 10 and 100 times more sensitive to the cytotoxic effects of asbestos fibers than normal human bronchial epithelial or fibroblastic cells, respectively. In addition, cultures of mesothelial cells that survived two cytotoxic exposures of amosite fibers were aneuploid with consistent specific chromosomal losses indicative of clonal origin. These aneuploid cells exhibit both altered growth control properties and a population doubling potential of greater than 50 divisions beyond the culture life span (30 doublings) of the control cells.

The effect of ipratropium bromide administered at two dosage levels, 40 and 80 mug, isoproterenol, 150 mug, and placebo using a metered dose inhaler was evaluated in ten adult patients with asthma in a double-blind, crossover study. The new atropine-like drug proved to be as effective a bronchodilator as isoproterenol in this study, although it had a later peak effect. Ipratropium bromide had a longer course of action than isoproterenol (4 hours compared to 1-2 hours) and was free of significant side effects. The larger dose of the new drug produced a slightly greater and longer-acting effect than the smaller dose. Ipratropium bromide seems to have had bronchodilator effects on both large and small airways.

Two boys are presented who fulfilled criteria for a diagnosis of idiopathic pulmonary hemosiderosis. A lung biopsy specimen from the first patient showed alveolar-capillary basement membrane abnormalities, together with abnormalities of capillary endothelial cells and hemosiderin-laden macrophages. A lung biopsy specimen from the second patient showed mainly capillary endothelial abnnormalities and interestitial fibrosis. Both patients had a noticeable improvement in symptoms and relative stabilization of their roentgenographic and pulmonary function abnormalities following azathioprine therapy.

We investigated the influence of serum factors on the uptake of various species of mycobacteria by human peripheral blood monocytes (PBM). On the basis of the percentage of PBM involved during in vitro uptake, the mycobacteria were of two distinct groups. The mycobacteria of one group, which consisted of Mycobacterium avium complex and M. chelonae, were taken up by many PBM; the other group, consisting of M. tuberculosis, M. kansasii, M. fortuitum, and M. gordonae, were taken up by fewer PBM. M. scrofulaceum was intermediate to these two groups on the basis of its uptake by PBM. Serum depleted of complement by heating or treatment with cobra venom factor significantly reduced the extent of PBM involvement with M. avium complex, indicating that complement is an important serum component mediating the uptake of M. avium complex organisms. Preincubation of mycobacteria with serum containing 10 mM EGTA [ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid] and 10 mM MgCl2 resulted in uptake by a high percentage of PBM, while preincubation in heated serum or serum containing 10 mM EDTA resulted in a significantly reduced percentage of PBM involved in uptake of M. avium complex organisms, indicating that these organisms are activators of the alternative pathway of complement. Incubation of M. avium complex organisms in human serum consumed 51% of the hemolytic complement activity. Parallel experiments indicated that serum had a lesser effect on the uptake of M. tuberculosis. Thus, serum is important in in vitro M. avium complex uptake by PBM; complement has a major role in the effect of serum, but this role is less important with M. tuberculosis.

Studies were undertaken to compare interferon production among a variety of lymphoreticular cells, with emphasis on the alveolar macrophage. Explanted cells from rabbit lung, spleen, peritoneum, bone marrow, and blood produced interferon in varying amounts in response to six of the seven viruses studied. The various lymphoreticular tissues responded differently to a single interferon-inducing virus, and each tissue produced varying amounts of interferon when stimulated by different viruses. In addition, glass-adherent rabbit alveolar macrophages produced more interferon than did the nonadherent subpopulation. Human blood and lung cells produced much less interferon than did the equivalent rabbit cells under similar conditions of stimulation. It appeared that interferon production may have been controlled by several variables, including the species, the type of inducer, and the type of tissue and cell.

Studies were performed to compare the cytotoxicity for human alveolar macrophages of a naturally occurring short-fiber chrysotile asbestos (RG 144) to that of a standard reference mixed-fiber (long and short) chrysotile asbestos (UICC chrysotile A. Rhodesian). Parallel studies were also performed with quartz (Min-U-Sil 15), a known macrophage toxin. On a mass basis, and after 24 hr incubation, RG 144 was more cytotoxic than the UICC standard reference fiber and less toxic than quartz (silica). The cytotoxic potential of RG 144 chrysotile was further enhanced after size reduction by milling. These findings may have important biologic implications with respect to the use of short-fiber asbestos in industry.

Home oxygen therapy is clearly beneficial for the chronically hypoxemic patient. Compressed gas, liquid oxygen and oxygen concentrators are the primary oxygen sources for home use. A number of oxygen-conserving devices are now available and may improve compliance. Reservoir cannulas, demand oxygen delivery systems and transtracheal oxygen are the latest examples of oxygen-conserving techniques.

Experiments were carried out to determine the effect of cocultivation of T-cell-enriched human peripheral blood lymphocytes with autologous alveolar macrophages on mitogen-induced proliferation as determined by [(3)H]thymidine uptake. Cells obtained by fiberoptic bronchoscopy and saline bronchial lavage from 14 normal volunteers were enriched for macrophages by adherence in plastic dishes for 1 h in RPMI 1640 medium supplemented with 10% fetal calf serum. Nonadherent mononuclear cells were prepared from heparinized venous blood after Ficoll-Hypaque sedimentation by passage over nylon wool columns. T-cell-enriched populations were incubated with and without alveolar macrophages, either in the presence or absence of phytohemagglutinin. In these experiments, the number of lymphocytes was held constant (10(5) per well), while the number of alveolar macrophages was varied (0.1 x 10(5) to 4.0 x 10(5) per well). Alveolar macrophages generally tended to stimulate phytohemagglutinin-induced lymphoproliferation at lymphocyte/macrophage ratios of 10:1 but consistently and significantly suppressed proliferation at ratios which approach those usually observed in recovered human bronchial lavage fluid, namely, 1:4. The suppressive effect of alveolar macrophages was observed as early as 48 h after culture initiation, while the magnitude of suppression increased with time. Suppression did not appear to be due to alteration in lymphocyte viability, nor was it sensitive to indomethacin. These results indicate that human alveolar macrophages can modulate the in vitro proliferative response of autologous peripheral blood lymphocytes. This observation may have relevance to interactions between alveolar macrophages and bronchial lymphocytes in the human lung in vivo.

The cellular content of bronchial lavage was studied in 14 patients with sarcoidosis and 20 normal volunteers. There was no alteration in the total number of cells recovered, except for the expected increase in cellularity in smokers. Nonsmoking patients with sarcoidosis had 19.6 per cent lymphocytes, compared to 8.1 per cent lymphocytes in nonsmoking control subjects. The percentage of alveolar macrophages showing spontaneous adherence of one or more bronchial lymphocytes were, respectively, 10.8 and 8.4 in nonsmoking and smoking patients with sarcoidosis, compared to 1.8 and 2.1, respectively, in nonsmoking and smoking control subjects.

Experiments were performed to evaluate the in vitro effects of Escherichia coli lipopolysaccharide on viability and function of human alveolar macrophages. Alveolar macrophages were obtained by fiberoptic bronchoscopy and saline bronchial lavage from 12 normal, nonsmoking volunteers. Cells were incubated with different concentrations of E. coli endotoxin for 1 and 24 h. Endotoxin (10 microgram/ml and more) was cytotoxic for alveolar macrophages after 24 h of incubation and induced significant inhibition of phagocytosis, adherence, and spreading. The effects of endotoxin on alveolar macrophage viability and function were dose and time dependent and were not influenced by indomethacin. Thus, human alveolar macrophages, like other mononuclear phagocytes, are extremely sensitive to endotoxin effects; these observations may be relevant in conditions in which endotoxin may be in contact with alveolar macrophages in vivo: endobronchial infections with gram-negative organisms, byssinosis, chronic bronchitis of grain handles, and humidifier fever.

Bronchopleural fistula and Hemophilus influenzae empyema developed in two patients with longstanding oleothorax. The first patient died after drainage with a pleurocutaneous flap, and a seven-rib thoracoplasty failed to resolve her infection. In the second, resection of the oleothorax cavity and left upper lobe resulted in cure.

A physical interaction between macrophages and lymphocytes was observed more frequently in bronchial lavage fluid obtained from patients with sarcoidosis than from normal volunteers, irrespective of their history of smoking. In this spontaneous interaction more than two lymphocytes were commonly seen adhering to a macrophage without evidence of cytoplasmic bridging or membrane fusion. To a greater extent than in normal volunteers, macrophages from patients with sarcoidosis were characterized by the appearance of a more highly irregular cell surface, more membrane bound inclusions, however, was positively correlated with the smoking history of the individual, and the number of surface projections (microvilli) of macrophages from smokers appeared to be reduced. Significant differences were not apparent in the nuclear or cellular diameters of macrophages from sarcoid and normal individuals.

To characterize the initial step in alveolar macrophage (AM)-lymphocyte (L) interaction in the human lung, we studied the ability of human AM to bind autologous blood L in vitro in the absence of antigen. AM were obtained by saline bronchial lavage through a fiberoptic bronchoscope. Monolayers of AM attached to glass bound autologous blood L prepared by Ficoll-Hypaque and nylon wool column separation. The AM-L binding increased from zero time to a maximum at 2 h and then declined to a zero time value at 18 h. The binding was dependent on the number of L added to the AM monolayers, with greatest binding at an AM:L ratio of 1:50. AM:L binding required viability of AM, but not of L, and was temperature dependent. Pretreatment of AM with iodoacetic acid, trypsin, neuraminidase, or colchicine diminished attachment of L at 2 h. Neuraminidase pretreatment of L resulted in increased binding to nontreated AM. Thus, a physical interaction between human AM and autologous peripheral blood L can occur in vitro in the absence of known antigen; similar interaction in vivo may play a role in the generation of cell-mediated immune responses in the lung.

Tuberculosis cases are increasing in the United States, partly because of the emergence of AIDS and the rise in the homeless population. Faster culture methods usually allow identification within two weeks. Research is being done on serologic and recombinant nucleic acid methods of detecting tuberculosis in various body fluids and secretions. A six-month treatment regimen for tuberculosis has proved to be effective, as have shorter courses of prophylactic therapy for tuberculin skin test converters.

Alveolar macrophages were obtained from human volunteers, smokers and nonsmokers, by bronchial lavage through a fiberoptic bronchoscope. Cells were incubated in a chemically defined medium containing [(14)C]sucrose (0.36 mM) and varying concentrations of rabbit serum. Pinocytosis was assessed by the cellular uptake of isotope over 30, 75, and 120-min periods. Pinocytic activity of smokers' cells was dependent on serum concentration but always less than the activity of nonsmokers' cells. The degree of pinocytosis by nonsmokers' cells was independent of serum concentration. It is concluded that the decreased level of pinocytic activity in smokers' alveolar macrophages as indicated by the uptake of sucrose in the presence of rabbit serum may represent a form of reticuloendothelial blockade.

An enzyme-linked immunosorbent assay (ELISA) was examined for its usefulness in detecting mycobacterial antigens in sputum. A double-antibody sandwich procedure was set up by using a commercially available hyperimmune serum directed against Mycobacterium bovis, BCG. The ELISA was able to detect 10 ng of protein per ml of BCG sonic extract. The system also clearly distinguished Mycobacterium tuberculosis organisms from Mycobacterium avium and Mycobacterium kansasii organisms. A total of 68 unknown sputum specimens submitted to the clinical laboratories for examination for tuberculosis were tested by ELISA. Of the 20 specimens that were smear positive and culture positive, 12 (60%) were positive by ELISA; 6 of the 11 (55%) smear-positive culture-negative samples were positive by ELISA; 1 of 2 (50%) of the smear-negative culture-positive samples was positive by ELISA; and only 3 of 35 (9%) of the smear-negative culture-negative samples were positive by ELISA. This approach offers promise as an aid in the presumptive differentiation of nontuberculous mycobacteria from the M. tuberculosis complex.