Kaoru Kawakami

Significance of IL‐1β and IL‐1 receptor antagonist (IL‐1Ra) in bronchoalveolar lavage fluid (BALF) in patients with diffuse panbronchiolitis (DPB)

We evaluated the effect of erythromycin therapy on pulmonary function tests and the airway inflammatory response of patients with DPB. The number of neutrophils in BALF obtained from DPB patients was significantly higher than that of healthy volunteers. Treatment with erythromycin (600 mg/day for 12.9 γδ+9.5 months (mean γδ+s.d.)) significantly reduced the total number of cells and neutrophils in the airway, and significantly improved pulmonary function tests. The levels of IL‐1β and IL‐8 were significantly higher in DPB compared with healthy volunteers (P < 0.05, P < 0.05, respectively). IL‐1 Ra in patients is considered to have a weak inhibitory activity for IL‐1β, with approximately five‐fold concentration of IL‐1β compared with that in healthy volunteers (approx. nine‐fold concentration of IL‐1β). Erythromycin therapy significantly reduced these cytokines to levels comparable to those of healthy volunteers, and produced a trend toward reduction in the level of IL‐1Ra in BALF. The level of IL‐1β correlated significantly with the concentration of neutrophils in BALF (r= 0.72, P < 0.01), as well as with the level of IL‐1Ra (r= 0.688, P < 0.05) and IL‐8 (r= 0.653, P < 0.05). A nearly significant or significant correlation was observed between the concentration of neutrophils and levels of IL‐1Ra or IL‐8 in BALF (r= 0.526, P= 0.053 or r= 0.776, P < 0.01, respectively). There was also a significant relationship between FEV, and the concentration of neutrophils in BALF (r= 0.524, P < 0.05). Our results suggest that the relative amounts of IL‐1β and IL‐1Ra or IL‐8 may contribute, at least in part, to the neutrophil‐mediated chronic airway inflammation in patients with chronic airway disease, and long‐term erythromycin therapy may down‐regulate the vigorous cycle between the cytokine network and neutrophil accumulation, with resultant reduction of neutrophil‐mediated inflammatory response.

Protective effect of granulocyte colony-stimulating factor (G-CSF) in a granulocytopenic mouse model of Pseudomonas aeruginosa lung infection through enhanced phagocytosis and killing by alveolar macrophages through priming tumour necrosis factor-alpha (TNF-α) production

We investigated the effects of G‐CSF in a granulocytopenic mouse model of Pseudomonas aeruginosa lung infection. The model was prepared by intratracheal instillation of the bacteria, while granulocytopenia was induced by intraperitoneal injection of 4.0 mg of cyclophosphamide (CPA). There was no difference in the survival rate between G‐CSF‐treated animals and the normal group, and the number of neutrophils in the blood and lung recovered to normal in the former group. However, the phagocytic and killing activities of neutrophils were lower in G‐CSF‐treated mice than in controls. Interestingly, the mortality rate increased significantly when anti‐TNF‐α antibody was combined with G‐CSF, although it was intermediate between CPA alone and CPA–G‐CSF‐treated mice. However, the improved mortality was not associated with a change in the number of neutrophils in the circulation and lung. Administration of anti‐TNF‐α antibody resulted in a significant suppression of TNF‐α in bronchoalveolar lavage fluid and of enhanced alveolar macrophage function (phagocytic and bactericidal activity) against P. aeruginosa in G‐CSF‐treated granulocytopenic mice. We showed also increased TNF‐α mRNA expression and TNF‐α production in vitro using G‐CSF‐pretreated alveolar macrophages compared with control untreated macrophages. Our results are the first evidence to suggest that G‐CSF provides a synergistic protective effect against lethal P. aeruginosa lung infection in the granulocytopenic host. This effect is probably due to enhancement of alveolar macrophage function through endogenous TNF‐α production, in addition to increasing the number of circulating neutrophils.

Phenotypic characterization of T cells in bronchoalveolar lavage fluid (BALF) and peripheral blood of patients with diffuse panbronchiolitis; the importance of cytotoxic T cells

We investigated the contribution of T cells in diffuse panbronchiolitis (DPB) by identifying T cell subsets in BALF of 36 patients with DPB, before and after long‐term treatment with macrolide antibiotics, and 16 healthy control subjects. The percentages of lymphocytes and CD3+γδ+ cells in BALF of DPB patients and control subjects were similar, but the absolute number of these cells was higher in DPB patients. Treatment resulted in a significant reduction in the absolute number of these cells. A further two‐colour analysis of T cell subsets in BALF showed a significantly higher ratio and number of CD8+HLA‐DR+ cells in DPB patients. Treatment resulted in a significant reduction of activated T cells. Most BALF CD8+ cells were CD8+CD11b− cytotoxic T cells. The number of these cells in BALF of DPB patients (26.69 ± 5.86 × 103/ml) was higher than the control (2.02 ± 0.38 × 103/ml; P < 0.001), and a significant reduction was observed after treatment (7.69 ± 2.59 × 103/ml; P < 0.01). The number of CD4+ cells was also higher in DPB patients than in controls, and most were CD4+CD29+ memory T cells. However, treatment did not influence the number of these cells. The number of lymphocytes, CD3+γδ+, CD8+CD11b−, CD8+HLA‐DR+, and CD4+CD29+ cells was higher in patients with bacterial infection than in those without bacterial infection, and interestingly, macrolide therapy reduced the number of lymphocytes, CD3+γδ+, CD8+CD11b− and CD8+HLA‐DR+ cells, irrespective of bacterial infection. In peripheral blood, the percentage of CD8+HLA‐DR+ cells was also higher in DPB patients than in healthy subjects, and significantly decreased after treatment. The percentage of CD8+CD11b− cells in peripheral blood was similar in DPB patients and normal subjects, and treatment significantly reduced the percentage of these cells. Finally, the expression of the adhesion molecules CD11a/CD18 (α/β‐chains of LFA‐1) on lung CD3+ cells and CD49d (α‐chain of VLA) on lung CD4+ cells was enhanced compared with that on peripheral blood in DPB patients. Our results suggest that elevation of memory T cells and activation of CD8+ cells, mainly cytotoxic T cells, in the airway lumen of DPB patients may contribute to chronic bronchial inflammation, possibly through up‐regulation of adhesion molecules. Our findings also indicate that macrolide antibiotics may have a direct or indirect suppressive effect on cytotoxic T cells, and as such, reduce inflammation and improve clinical condition.

Effect of roxithromycin on peripheral neutrophil adhesion molecules in patients with chronic lower respiratory tract disease

To evaluate the effects of roxithromycin in patients with chronic lower respiratory tract disease including diffuse panbronchiolitis, we studied lymphocyte function-associated antigen-1 (LFA-1) and Mac-1, neutrophil adhesion molecules, using peripheral neutrophils from healthy volunteers and from patients with chronic lower respiratory tract disease. The number of Mac-1 expressed on neutrophils of the patients was significantly greater (0.68 +/- 0.16) than in the healthy subjects (0.45 +/- 0.14), while the number of LFA-1 expressed on neutrophils of the patients was nearly similar to that in the healthy volunteers (0.95 +/- 0.10 vs 0.89 +/- 0.11). The neutrophil numbers in bronchoalveolar lavage fluid and the number of Mac-1 expressed on peripheral neutrophils significantly decreased in all patients who responded clinically to a low dose of roxithromycin for a long period of time (56.0 +/- 25.2 vs. 22.7 +/- 19.7%, p < 0.05 and 0.70 +/- 0.16 vs. 0.59 +/- 0.08, p < 0.05, respectively), whereas roxithromycin had no effect on the quantitative expression of LFA-1 (0.96 +/- 0.14 to 1.00 +/- 0.09, not significant) in all responders.

Immunological competence and nutritional status in patients with lung cancer.

Abstract. The rate of infection in patients with malignant disease is significantly higher than in patients with benign disease. To investigate whether immunological competence is impaired in patients with lung cancer, we assessed neutrophil function (chemotaxis, phagocytosis, bacterial killing activity, and superoxide production), monocyte function (phagocytosis and killing activity), lymphocyte subsets using flow cytometry, and proliferation of lymphocytes stimulated by phytohemagglutinin, concanavalin A, and pokeweed mitogen. Studies were performed on 22 untreated patients with lung cancer and 21 age-matched healthy volunteers. Nutritional status was assessed by Niedermans nutritional index. In patients with lung cancer neutrophil chemotaxis, monocyte phagocytosis and killing, proliferation of lymphocytes stimulated by phytohemagglutinin and concanavalin A, but not pokeweed mitogen, and the number of natural killer cells were significantly lower than in healthy volunteers, whereas γδ T cells were increased (p < 0.05). The mean score on Niedermans nutritional index was worse in patients than in healthy volunteers (p < 0.001). Our results suggest that the impaired immunological competence and undernutrition may be among the mechanisms causing increased susceptibility to infection in patients with lung cancer.

Clinical and Immunological Evaluation of Infection in Patients on Hemodialysis

Infection is a major complication associated with increased morbidity and mortality in patients on hemodialysis. We analyzed the incidence and type of infection occurring in 4841 patients on hemodialysis between 1986 and 1993 in our hospital and 11 other hemodialysis centers. Infection was noted in 193 patients (4.98 infections/1000 patients/year). Pneumonia (n=71) and bacteremia (n=24) were the 2 most common infections, followed by tuberculosis (n=14), herpes zoster infections (n=12) and infections at the vascular access site (n=12). The most commonly isolated organism in pneumonia, bacteremia and vascular access site infections wasStaphylococcus aureus. Analysis of the prognosis of patients with pneumonia showed a mortality rate of 50% in patients greater than 60 years old, which was significantly higher than that of younger patients (6.7%,P<0.01), whereas the mortality rate in patients with bacteremia was not different between the 2 age groups (60.0% vs. 57.9%, respectively). We also analyzed changes in immunological function and nutritional status in 16 patients on hemodialysis and 21 healthy control subjects. Although the phagocytic and bactericidal activities of neutrophils and monocytes were not different between the groups, superoxide production, the percentage of natural killer cells and the degree of blastoid transformation with phytohemagglutinin stimulation were significantly lower in hemodialysis patients. Low levels of Nidermans index and serum albumin and transferrin indicated poor nutritional status in these patients. Furthermore, the degree of Nidermans index and serum albumin significantly correlated with impairment of immunological function, such as reduced blastoid transformation and the number of lymphocytes. Our results suggest that analysis of the patterns of infection in patients on hemodialysis should provide better management and that improvement of malnutrition may ameliorate impaired immunity in hemodialysis patients.