B-lymphocyte aggregates in alveoli from a child with hypersensitivity pneumonitis (bird breeders lung).

BACKGROUND: Hypersensitivity pneumonitis is an interstitial lung disease mediated through a patient's immunologic response to a variety of inhaled organic dusts. Studies of the cellular components of lavage fluid from patients with this disease show marked increases of CD8+ suppressor/cytotoxic T-lymphocytes. OBJECTIVE: In this study, we identified, in addition to the expected suppressor T-cells and natural killer cells, follicle-like aggregates of B-cells in the lung interstitium of an affected patient. METHODS: The patient was an 11-year-old non-asthmatic, Caucasian male who presented with a 4-month history of progressive dyspnea, cough, and fever. The home contained nine cockatiel and two doves. Admission pulmonary functions revealed a restrictive pattern with diminished diffusion capacity. Prior to a diagnosis, the patient underwent bronchoalveolar lavage and transbronchial biopsy. Serum precipitins were eventually positive to pigeon (which cross-reacts with dove) droppings. The symptoms resolved after a prolonged course of prednisone. RESULTS: Analysis of bronchoalveolar lavage lymphocyte population revealed a predominance of CD8+ cells (50%) with 85% expressing the activation marker HLA-DR. The percentage of CD4+ and CD56+ were 32% and 16%, respectively. The transbronchial biopsy revealed CD20+ follicle-like aggregates within the lung interstitium. CONCLUSIONS: The histopathologic findings confirm that in hypersensitivity pneumonitis, the predominant immune response is an infiltrate of CD8+ T cells. The presence of B cell aggregates, however, may indicate that the local synthesis of antibody may be involved in an antibody-dependent cellular cytotoxic mechanism.

Airway function tests and vocal cord paralysis in lung transplant recipients.

Maximum expiratory and inspiratory flow-volume (MEFV, MIFV) curves, specific airway conductance (sGaw), and flexible fiberoptic laryngoscopy were examined in 8 pediatric lung transplant recipients with vocal cord paralysis (VCP). Six were heart-lung (H-L) and 2 double-lung (D-L) recipients, 7 had left VCP, and 1 had right VCP. Based on the pulmonary function tests (PFT), 2 subgroups could be distinguished in the 8 recipients with VCP. Group A (5/8 recipients; mean age, 13 +/- 3.4 years; mean height, 144.3 +/- 12.3 cm) had significantly reduced specific airway conductance (sGaw; < 2 SD from predicted) and normal MEF25, MEF50, peak expiratory flow (PEF), forced expiratory volume in 1 second (FEV1), and %FEV1/forced vital capacity (FVC); this pattern suggested variable extrathoracic airway obstruction. PIF was normal in 4/5 and reduced in 1/5 of these recipients. Group B (3/8 recipients with VCP; mean age, 17 +/- 2.4 years; mean height, 156.3 +/- 12.0 cm) had significantly reduced sGaw, MEF25, MEF50, PEF, FEV1, and %FEV1/FVC, implying primarily small airway obstruction. These recipients had bronchiolitis obliterans. The results suggest that a pattern of reduced sGaw and normal MEFs, PEF, FEV1, and PIF should raise the possibility of VCP in patients after lung transplantation. sGaw is more sensitive than PIF and PEF in identifying airway obstruction due to VCP, and should be routinely included in the follow-up evaluation of lung transplant recipients.

Exercise testing in pediatric heart, heart-lung, and lung transplant recipients.

Cardiorespiratory responses to progressive exercise were examined in 38 children who had undergone heart (n = 16), heart-lung (n = 13), or double-lung (n = 9) transplantation, and in 41 healthy controls. The four groups were similar in age, but the control subjects and heart transplant recipients were significantly larger than the heart-lung and lung recipients as assessed by body mass index (BMI). Time since transplant was significantly longer in the heart (601 days) compared with heart-lung (146 days) and lung (125 days) transplant groups. Physical work capacity and peak oxygen uptake were significantly reduced (43 to 64% of predicted) in the three transplant groups compared with the control group. Peak heart rate (percent predicted) was significantly higher in the control subjects (94%) compared with the heart (66%), heart-lung (70%), and lung (77%) transplant recipients. Peak minute ventilation was significantly higher in the control (72.9 L/min) and heart transplant (51.0 L/min) groups than the heart-lung (37.4 L/min) and lung (41.3 L/min) transplant groups. The control group had a higher peak tidal volume than the three transplant groups, and a higher peak respiratory rate than the lung transplant recipients. Correlational analysis revealed that physical work capacity (PWC) was significantly related to heart rate at peak exercise (HRpeak) and minute ventilation at peak exercise (VE-peak) in the heart transplant recipients, BMI, VEpeak, and FEV1 in the heart-lung transplant recipients, and BMI, HRpeak, VEpeak, FEV1, and number of days posttransplant in the lung transplant recipients. In addition to these variables, physical deconditioning and factors related to pharmacotherapy, infection, and rejection may also contribute to the decreased PWC observed in the transplant recipients.

Identification and expression of the Drosophila adipokinetic hormone gene.

Drosophila adipokinetic hormone (DAKH) is an eight amino acid member of a large arthropod neuropeptide family. The gene encoding the peptide precursor has been identified and sequenced providing an inferred precursor structure of 79 amino acids including a 46 amino acid carboxy-terminal fragment of unknown function. In situ hybridization identifies sites of DAKH synthesis towards the base of the third larval instar ring gland. Like other RPCH (red pigment concentrating hormone)/AKH family peptides, DAKH can act as a cardioaccelerator at least in prepupae. Peptide levels measured in wildtype and mutant flies possessing one or three copies of the DAKH gene suggest that the amount of neuropeptide per fly is tightly regulated.

Hypertrophic osteoarthropathy in a child with follicular bronchiolitis.

Hypertrophic osteoarthropathy (HOA) is a syndrome affecting the bones, soft tissue, and joints, often occurring in association with chronic pulmonary disorders. Radiography has traditionally been the imaging modality employed to confirm this diagnosis. However, radionuclide bone imaging provides a sensitive method for the detection of HOA and correlates well with the clinical manifestations. The authors's describe the case of a child with HOA in association with follicular bronchiolitis, a rare chronic pulmonary disorder, whose HOA was diagnosed by radionuclide imaging.

Pseudomonas cepacia empyema necessitatis after lung transplantation in two patients with cystic fibrosis.

Lung transplantation is an accepted modality for patients with cystic fibrosis (CF) who have end-stage respiratory failure. The postoperative course of these patients is often complicated by serious infections with organisms such as Pseudomonas aeruginosa and Pseudomonas cepacia that may be multiply resistant to conventional antimicrobial agents. We describe two patients with CF who, after double lung transplantation, developed the unusual complication of empyema and empyema necessitatis due to P cepacia that was resistant to all tested antibiotics.

Pediatric lung transplantation for graft-versus-host disease following bone marrow transplantation.

Nine years after receiving a bone marrow transplant for aplastic anemia, a 14-year-old girl with severe pulmonary disease associated with graft-versus-host disease received a double lung transplant. Subsequent to lung transplant, her lung function improved dramatically (FEV1 increasing from 20 to 73 percent predicted normal, residual volume decreasing from 316 to 130 percent predicted normal values). The patient is currently well 15 months after transplant, while receiving immunosuppression consisting of FK506 and azathioprine. Double lung transplantation may offer a therapeutic option for the treatment of graft-versus-host pulmonary disease in selected patients.

Experience with pediatric lung transplantation.

Heart-lung transplantation and lung transplantation have become accepted techniques in adult patients with end-stage cardiopulmonary disease. We report here our experience between July 1985 and March 1993 with 34 children (< 20 years) who underwent heart-lung (n = 18) or lung transplantation (n = 17). Indications for transplantation included cystic fibrosis (n = 9), congenital heart disease with Eisenmenger complex (n = 9), primary pulmonary hypertension (n = 8), pulmonary arteriovenous malformations (n = 2), desquamative interstitial pneumonia (n = 2), Proteus syndrome with multicystic pulmonary disease (n = 1), graft-versus-host disease (n = 1), rheumatoid lung disease (n = 1), and bronchiolitis obliterans and emphysema (n = 1). Twenty-six patients (76%) have survived from 1 to 88 months after transplantation; most patients have returned to an active lifestyle. Of the eight deaths, four were due to infections, two to multiorgan failure, 1 to posttransplant lymphoproliferative disease, and one to donor organ failure. Four of the patients who died had cystic fibrosis. Despite considerable morbidity related to infection, rejection, and function of the heart-lung and lung allograft in some patients, our results with this potentially lifesaving procedure in the pediatric population have been encouraging.

Bronchoalveolar lavage and transbronchial biopsy in children following heart-lung and lung transplantation.

Between July 1985 and March 1992, 20 children received either heart-lung (11), double lung (8), or single lung (1) transplants at our center. Since 1988, flexible fiberoptic bronchoscopy with bronchoalveolar lavage and transbronchial biopsy have been carried out to monitor for rejection or infection in these patients. As of March 31, 1992, we have performed a total of 112 transbronchial biopsies in our patients, who ranged from 6.8 to 18 years of age and 19.3 to 67.3 kg in weight. All but two of these procedures were carried out using conscious sedation and a transnasal approach. Four to seven biopsy samples were obtained at each procedure. One patient had hemorrhage (< 100 ml) and no patient had pneumothorax as a complication. Of the biopsy samples, 72.4 percent had a surface area of greater than 2 mm2, and 89.5 percent of the biopsy samples were deemed adequate for pathologic interpretation. We believe that for the majority of pediatric lung or heart-lung recipients, flexible bronchoscopy and transbronchial biopsy using conscious sedation and a transnasal approach is safe and permits the recovery of adequate tissue for pathologic evaluation. The avoidance of general anesthesia, endotracheal intubation, and mechanical ventilation at the time of bronchoscopy and transbronchial biopsy probably decreases the likelihood of pneumothorax as a complication of the procedure.

The closely related neuropeptide genes encoding adipokinetic hormones I and II have very different 5'-flanking regions.

Adipokinetic hormones I and II are 10- and 8-amino-acid grasshopper neuropeptides that are derived from 63- and 61-amino-acid peptide precursors, respectively. Each precursor is encoded by a separate gene consisting of three very small exons separated by two large introns. The identical exon structure of the two genes suggests that they evolved through duplication of a common ancestral gene. Despite the precise conservation of exon structure and the similarity of the coding sequences, the two genes have very different 5'-flanking regions, suggesting that they are differentially regulated. For example, sequences similar to the vertebrate insulin enhancer elements NIR and FAR are present upstream of the promoter region of the adipokinetic hormone II gene, but not in the adipokinetic hormone I gene. Both of these insect genes contain short interspersed repetitive DNA sequences in their introns that may have facilitated a gene duplication event.

Accessory cell function of blood monocytes and alveolar macrophages after human lung transplantation.

Infection is a major complication of organ transplantation, and the lung is the most common site in recipients of a pulmonary allograft. The generation of an immune response both systemically and in the lungs is a major line of defense against infection. Therefore, we examined the ability of blood monocytes (BM) and alveolar macrophages (AM) recovered from lung transplant recipients without evidence of infection or rejection and from normal subjects to act as accessory cells in mitogen- and antigen-induced proliferation of autologous lymphocytes (Ly) and to stimulate an allogeneic (MLR) and autologous mixed lymphocyte reaction (AMLR). Proliferation of autologous Ly in the presence of mitogen and antigen and of allogeneic Ly stimulated by BM was significantly reduced in the lung recipients when compared with those in the normal subjects. Impaired Ly proliferation may result from inadequate presentation of antigen by recipient BM, heightened suppressive activity of BM, or the inability of recipient Ly to respond to proliferative signals. We believe that our results strongly support a role for inadequate presentation of antigen by BM. Inadequate antigen-driven stimulation could be one reason why transplant recipients have an increased susceptibility to infection. Somewhat unexpected was the finding that AM from lung recipients functioned nearly as well as AM from normal subjects as accessory cells. Although they failed to support mitogen-induced stimulation normally, AM from lung recipients were as efficient as autologous BM and AM from normal subjects in supporting Ly proliferation for soluble antigen and alloantigen.(ABSTRACT TRUNCATED AT 250 WORDS)

The fruitfly Drosophila melanogaster contains a novel charged adipokinetic-hormone-family peptide.

A member of the RPCH/AKH (red-pigment-concentrating hormone/adipokinetic hormone) family of arthropod neuropeptides was identified in the fruitfly Drosophila melanogaster, and its structure was determined by automated Edman degradation and m.s. using fast-atom-bombardment ionization and a tandem hybrid instrument capable of high sensitivity. The sequence of this peptide, which we call 'DAKH', is pGlu-Leu-Thr-Phe-Ser-Pro-Asp-Trp-NH2 (where pGlu is pyroglutamic acid and Trp-NH2 is tryptophan carboxyamide). H.p.l.c. analyses of extracts of the three body segments revealed that more than 80% of the peptide is contained in the thorax. Although DAKH is typical of family members in its general structure and distribution in the animal, it is unique in containing a residue which is charged under physiological conditions. The evolutionary significance of this change is considered.

The structurally similar neuropeptides adipokinetic hormone I and II are derived from similar, very small mRNAs.

The grasshopper neuropeptides adipokinetic hormone (AKH) I and II were among the first of an extensive family of structurally similar arthropod hormones and neuroregulators to be isolated and sequenced. This paper reports the cloning of cDNAs derived from the unusually small mRNAs (550 bases) which code for the precursors of AKH I and II from Schistocerca nitans. Sequence analysis of the cDNAs indicates that AKH I and II are derived from small precursor proteins (63 and 61 amino acids) which are 55% identical in amino acid sequence. Each contains a 22-amino acid hydrophobic leader sequence followed by the AKH I or II sequence and an additional 28-amino acid carboxyl-terminal peptide of unknown function. Significant homology at the nucleic acid level (64% identity) is confined to the coding region of the mRNA sequences. Preliminary DNA blot analyses suggest that a single gene codes for each, and that the genes for AKH I and II may be linked. Genomic blots from various tissues fail to suggest that the high level of expression of AKH in the corpora cardiaca is due to tissue specific gene amplification.

Use of bronchoalveolar lavage in immunocompromised children with pneumonia.

Because pneumonia in the immunocompromised host presents a diagnostic dilemma to the pediatrician, we prospectively studied the use of bronchoalveolar lavage (BAL) with flexible fiberoptic bronchoscopy in 14 immunocompromised children with pneumonia over a 5-month period. The children received immunosuppressive agents because of organ transplants, cancer, or systemic lupus erythematosus. A diagnosis was made by BAL in 10 (71%) of the 14 children. Pathogenic organisms included Pneumocystis carinii in six, cytomegalovirus (CMV) in two, Aspergillus fumigatus in one, and a mixed infection of Candida albicans and CMV in one. There were no complications. Because BAL by flexible fiber-optic bronchoscopy is a rapid and safe procedure and a diagnosis can be made in a majority of cases, we recommend its use in immunocompromised children with pneumonia before resorting to lung biopsy.

Persistent infection of some standard cell lines by lymphocytic choriomeningitis virus: transmission of infection by an intracellular agent.

Cell-free cytoplasmic extracts of the Syrian hamster cell lines C13/SV28 and BHK-21F were immunogenic in Syrian hamsters. The resulting antisera cross-reacted completely with antisera against lymphocytic choriomeningitis virus (LCMV) in an immunoradiometric assay employing BHK-21F antigen. Several other Syrian hamster cell lines not previously known to be infected with LCMV were also strongly positive when assayed for viral antigens. Also, several mouse sera and antisera raised in Syrian hamsters against cells transformed by papovaviruses had high titers of anti-LCMV activity. No cytopathic effect was evident in any of the persistently infected cell lines. Culture media from these cells were not infectious and showed no evidence of defective interfering particles. However, cell-free extracts of all the persistently infected cells contained material capable of transmitting the persistent infection to uninfected cells of Syrian hamsters, rats, mice, green monkeys, and humans. The onset of infection is much slower than when LCMV virions are used. When 2 X 10(6) uninfected BHK cells were treated with an extract from 100 persistently infected cells, the new infection was apparent within about 12 days. When an extract from 10(6) cells was used, the new infection was apparent within about 5 days, but not sooner. The intracellular infectious material was sensitive to treatment with deoxycholate, Nonidet P-40, or ether but resistant to treatment with RNase or trypsin. It was also large (5,000S) and heterodisperse on sucrose gradients. The infectious material was probably contained in large lipid vesicles and their integrity was probably essential for infection. When a few persistently infected cells were cocultivated with many uninfected cells, a few discrete colonies positive for LCMV antigens were observed after about 5 days. Since the culture media were not infectious, the infection probably spread by cell-cell contact. Several different experiments indicated that interferon did not play a major role in mediating persistence in this case. Persistent infections by LCMV can be maintained without expression of extracellular virus particles and without appearance of large amounts of viral antigens on the cell surface. Cell-cell contact could still allow transmission of intracellular infectious material. In an animal, these properties could circumvent immune surveillance.