Induction of lymphocytic inflammatory changes in lung interstitium by human T lymphotropic virus type I

Human T-Cell Leukemia Virus Type 1 Changes Leukocyte Number and Oxidative Stress in the Lung and Blood of Female BALB/c Mice

BACKGROUND

Human T-cell leukemia virus type 1(HTLV-1) infection is likely to induce nonneoplastic inflammatory pulmonary diseases. Therefore, an experimental study was conducted to evaluate the leukocytes' number alteration and oxidative stress in the lung and blood of HTLV-1-infected BALB/c mice, which could be of benefit for the recognition of HTLV-1 mechanism in the induction of pulmonary disorders.

MATERIALS AND METHODS

Twenty female BALB/c mice were divided into two groups of control and HTLV-1-infected animals. The HTLV-1-infected group was inoculated with 106 MT-2 HTLV-1-infected cells. Two months later, the infection was confirmed using real-time polymerase chain reaction, and then lung pathological changes, total and differential inflammatory cell counts in the blood and bronchoalveolar lavage fluid (BALF), along with oxidative stress biomarker levels in the BALF and lung tissue were evaluated.

RESULTS

In the HTLV-1-infected group, the peribronchitis score (P < 0.01), the number of total leukocytes, neutrophils, lymphocytes, and monocytes (P < 0.05) in the blood and BALF were increased. The number of eosinophils in the blood of the HTLV-1-infected group was higher than in the control group (P < 0.01), whereas the number of basophils of BALF was increased in the HTLV-1-infected group (P < 0.001). The lung and BALF oxidative stress results showed that the MDA level was increased, while the total thiol level and superoxide dismutase activity were decreased in the HTLV-1-infected group (P < 0.01).

CONCLUSION

The HTLV-1 infection seems to induce pulmonary inflammatory reactions by recruiting leukocytes as well as inducing oxidative stress in the lung tissue.

Human T-cell leukaemia virus type 1 associated pulmonary disease: clinical and pathological features of an under-recognised complication of HTLV-1 infection

The lung is one of several organs that can be affected by HTLV-1 mediated inflammation. Pulmonary inflammation associated with HTLV-1 infection involves the interstitium, airways and alveoli, resulting in several clinical entities including interstitial pneumonias, bronchiolitis and alveolitis, depending on which structures are most affected. Augmentation of the inflammatory effects of HTLV-1 infected lymphocytes by recruitment of other inflammatory cells in a positive feedback loop is likely to underlie the pathogenesis of HTLV-1 associated pulmonary disease, as has been proposed for HTLV-1 associated myelopathy. In contrast to the conclusions of early case series, HTLV-1 associated pulmonary disease can be associated with significant parenchymal damage, which may progress to bronchiectasis where this involves the airways. Based on our current understanding of HTLV-1 associated pulmonary disease, diagnostic criteria are proposed.

Lymphocytic focus score is positively related to airway and interstitial lung diseases in primary Sjögren's syndrome

OBJECTIVE

Although high-resolution computed tomography (HRCT) is useful for the characterization of minute morphological changes in the lungs, no study has investigated risk factors for lung involvement detected by HRCT in patients with Sjögren's syndrome with or without respiratory symptoms. The aim of the current study was to investigate risk factors for lung involvement in patients with primary Sjögren's syndrome detected by HRCT, with a particular focus on airway and interstitial lung diseases.

METHODS

We performed a retrospective cohort study of patients with primary Sjögren's syndrome and investigated risk factors for lung involvement detected by HRCT. A total of 101 patients with primary Sjögren's syndrome with initial HRCT examinations were enrolled.

RESULTS

Higher age, dry mouth, and higher labial gland biopsy focus scores (≥4) were risk factors for airway diseases (odds ratio [OR] 1.064 confidence interval [CI] 1.026-1.102, OR 8.795 CI 2.317-33.378 and OR 3.261 CI 1.100-9.675, respectively) in the multivariable analysis. Higher age, male sex, and higher labial gland biopsy focus scores (≥4) were risk factors for interstitial lung diseases (OR 1.078 CI 1.032-1.127, OR 12.178 CI 1.121-132.307 and OR 3.954 CI 1.423-10.987, respectively) in the multivariable analysis. The presence of anti-T-lymphotropic virus type 1 antibodies was significantly more common in patients with airway diseases.

CONCLUSIONS

This study showed significant associations of labial gland biopsy focus scores and dry mouth with pulmonary manifestations in patients with primary Sjögren's syndrome. Focus scores as well as dry mouth may reflect lymphoproliferative activity in the lungs in patients with primary Sjögren's syndrome.

Increased expression of HBZ and Foxp3 mRNA in bronchoalveolar lavage cells taken from human T-lymphotropic virus type 1-associated lung disorder patients

OBJECTIVE

Human T-lymphotropic virus type 1 (HTLV-I) causes adult T-cell leukemia/lymphoma (ATLL), and is associated with chronic inflammatory diseases, including inflammatory pulmonary diseases. HTLV-I bZIP factor (HBZ), which is expressed in all adult T-cell leukemia cells, plays a critical role in the development of lymphoma and systemic inflammation. HTLV-I is harbored by CD4(+) T cells that express forkhead box P3 (Foxp3), and HBZ interacts with Foxp3. This study investigated the chest computed tomography (CT) findings and expression of HBZ and Foxp3 in the bronchoalveolar lavage (BAL) cells from patients with HTLV-I-associated lung disorders.

METHODS

CT scans obtained from 37 patients (10 men and 27 women, aged 37-77 years) with HTLV-I-associated lung disorders were retrospectively evaluated. The expression levels of HBZ and Foxp3 mRNA in BAL cells and the levels of inflammatory cytokines in the BAL fluid (BALF) from patients were compared with those in control subjects.

RESULTS

CT scans frequently revealed a diffuse panbronchiolitis (DPB)-like pattern, along with a nonspecific interstitial pneumonia (NSIP) pattern. An analysis of the BALF revealed lymphocytosis and increased expression of HBZ mRNA in patients with HTLV-I-associated lung disorders. The expression of Foxp3 mRNA positively correlated with the percentages of lymphocytes present in the BALF. The inflammatory cytokine and IL-10 levels were significantly increased in the BALF from patients with HTLV-I-associated lung disorders.

CONCLUSION

The NSIP pattern may be a manifestation of pulmonary involvement in HTLV-I-infected patients, as is the DPB-like pattern. HBZ and Foxp3 likely have a role in the development of lung inflammation.

CT scans of the chest in carriers of human T-cell lymphotropic virus type 1: presence of interstitial pneumonia

RATIONALE AND OBJECTIVES

To evaluate pulmonary findings on computed tomography (CT) scans in carriers of human T-lymphotropic virus type 1 (HTLV-1).

MATERIALS AND METHODS

This retrospective study was approved by the Institutional Review Board at each institution, and informed consent was waived. Patients who were diagnosed with adult T-cell lymphoma/leukemia or collagen vascular disease were excluded from the study. Chest CT of 106 HTLV-1 carriers (54 females and 52 males; age range 44-94 years) were initially evaluated by two chest radiologists. Assessed CT findings included centrilobular nodules, thickening of bronchovascular bundles, ground-glass opacity, bronchiectasis, interlobular septal thickening, consolidation, honeycombing, crazy-paving appearance, enlarged lymph nodes, pleural effusion, and pericardial effusion. Three chest radiologists secondarily evaluated the CT scans with the abnormal findings to judge the presence of interstitial pneumonia patterns or a bronchiolitis/bronchitis pattern.

RESULTS

Abnormal CT findings were found in 65 (61.3%) patients, including ground-glass opacity (n = 33), bronchiectasis (n = 28), centrilobular nodules (n = 25), and interlobular septal thickening (n = 19). Honeycombing (n = 5) and crazy-paving appearance (n = 3) were also observed. Based on the CT findings, 10 subjects were diagnosed with interstitial pneumonia (usual interstitial pneumonia pattern, n = 3; nonspecific interstitial pneumonia pattern, n = 5; organizing pneumonia pattern, n = 2; respectively). Twenty subjects were diagnosed with the bronchitis/bronchiolitis pattern.

CONCLUSION

Although the bronchiolitis/bronchitis pattern is predominant on chest CT in HTLV-1 carriers, the HTLV-1 infection is associated with various interstitial pneumonias.

Soluble form of Fas and Fas ligand in serum and bronchoalveolar lavage fluid of individuals infected with human T-lymphotropic virus type 1

Human T-lymphotropic virus type 1 (HTLV-1) carriers are known to develop pulmonary complications characterized by T-lymphocytic alveolitis. The aim of this study was to determine the profile and role of soluble Fas (sFas) and sFas ligand (sFasL) in the lung of asymptomatic HTLV-1 carriers. We measured sFas and sFasL levels in serum and bronchoalveolar lavage fluid (BALF) of 16 seropositive asymptomatic HTLV-1 carriers and 32 healthy subjects. The serum levels of both sFas and sFasL were significantly higher in HTLV-1 carriers than in the control. In BALF, the percentage of lymphocytes and CD4 positive T-cells, and the levels of sFasL were also significantly higher in asymptomatic carriers than the control, but there were no significant differences in sFas levels between the two groups. There was a significant correlation between BALF sFasL levels and serum sFasL levels and percentage of CD4 positive T-cells in BALF. Our results suggest that the increased levels of sFasL in the lung of asymptomatic HTLV-1 carriers are associated with accumulation of CD4 positive T-cells, and that resistance to apoptosis in HTLV-1 infected T-cells and overproduction of sFasL could contribute to T-lymphocytic alveolitis by down-regulating Fas-FasL mediated apoptosis.

Clinical similarities and differences between human T-cell lymphotropic virus type 1-associated bronchiolitis and diffuse panbronchiolitis

STUDY OBJECTIVES

Human T-cell lymphotropic virus type 1 (HTLV-1)-associated bronchiolitis and diffuse panbronchiolitis might overlap. We examined whether these conditions can be differentiated by comparing their clinical features and the effect of long-term macrolide treatment.

PATIENTS AND METHODS

Fifty-eight Japanese patients, including 15 with HTLV-1-associated bronchiolitis and 43 with diffuse panbronchiolitis. Both conditions were clinically compared using the clinical criteria for diffuse panbronchiolitis, including findings from CT scans and BAL fluid testing. Pulmonary function, blood gas levels, and cold hemagglutinin (CHA) levels were assessed before and after long-term treatment with macrolides. Interleukin-2 receptor (IL-2R) expression in T cells obtained from the BAL fluid of patients with HTLV-1-associated bronchiolitis or diffuse panbronchiolitis was analyzed by flow cytometry.

RESULTS

Clinical, laboratory, radiologic, and bacterial features were strikingly similar in both groups, except for the fact that patients with HTLV-1-associated bronchiolitis had a higher ratio of IL-2R-positive cells in the BAL fluid. The histopathologic features were also similar. Long-term treatment with macrolides improved PaO(2), FEV(1), and CHA in patients with HTLV-1-associated bronchiolitis to a lesser extent than in those with diffuse panbronchiolitis, and PaO(2) and FEV(1) in the group of patients with HTLV-1-associated bronchiolitis who had high IL-2R levels did not respond after therapy.

CONCLUSIONS

These findings showed that the clinicopathologic features of the two conditions are quite similar, suggesting that diffuse panbronchiolitis is a chronic pulmonary manifestation of HTLV-1 infection. However, HTLV-1-associated bronchiolitis might be associated with conditions that are distinct from those of diffuse panbronchiolitis based on the different responses to macrolide treatment and the difference in the number of activated T cells bearing IL-2R in the lungs.

High expression of p40(tax) and pro-inflammatory cytokines and chemokines in the lungs of human T-lymphotropic virus type 1-related bronchopulmonary disorders

STUDY OBJECTIVE

Human T-lymphotropic virus type 1 (HTLV-1) is closely associated with the development of certain pulmonary diseases, such as bronchiolitis, although the pathologic mechanism remains unclear. To elucidate the pathogenesis of HTLV-1-associated bronchopulmonary disorders, we analyzed the relationship between expression of p40(tax), a regulatory component of HTLV-1 that stimulates various host genes, and synthesis of pro-inflammatory cytokines and chemokines by cells in BAL fluid (BALF) obtained from HTLV-1-infected patients.

DESIGN

Reverse transcription-polymerase chain reaction was used to compare the expression of p40(tax) and pro-inflammatory cytokines and chemokines messenger RNA (mRNA) in BALF of 10 HTLV-1 carriers and 7 healthy subjects. We also studied the correlation between these parameters and the proportion of lymphocytes in BALF.

RESULTS

The expression levels of pro-inflammatory cytokines (interferon [IFN]-gamma, interleukin-2) and chemokines (monocyte chemotactic protein-1, macrophage inflammatory protein [MIP]-1alpha, IFN-gamma-inducible protein-10 [IP-10]) were significantly higher in BALF of patients than of healthy subjects. The expression of IFN-gamma and MIP-1alpha mRNA correlated with that of p40(tax). IFN-gamma and IP-10 mRNA expression correlated with the proportion of lymphocytes in BALF. The percentage of lymphocytes in BALF increased with higher expression levels of p40(tax) mRNA, although the correlation was not significant.

CONCLUSION

Our results suggested that p40(tax) seems be involved in the development of HTLV-1-associated bronchopulmonary disorders at least in part through the local production of pro-inflammatory cytokines and chemokines.

Pulmonary function testing in HTLV-I and HTLV-II infected humans: a cohort study

BACKGROUND

HTLV-I infection has been linked to lung pathology and HTLV-II has been associated with an increased incidence of pneumonia and acute bronchitis. However it is unknown whether HTLV-I or -II infection alters pulmonary function.

METHODS

We performed pulmonary function testing on HTLV-I, HTLV-II and HTLV seronegative subjects from the HTLV outcomes study (HOST), including vital capacity (VC), forced expiratory volume in one second (FEV1), and diffusing lung capacity for carbon monoxide (DLCO) corrected for hemoglobin and lung volume. Multivariable analysis adjusted for differences in age, gender, race/ethnicity, height and smoking history.

RESULTS

Mean (standard deviation) pulmonary function values among the 257 subjects were as follows: FVC = 3.74 (0.89) L, FEV1 = 2.93 (0.67) L, DLCOcorr = 23.82 (5.89) ml/min/mmHg, alveolar ventilation (VA) = 5.25 (1.20) L and DLCOcorr/VA = 4.54 (0.87) ml/min/mmHg/L. There were no differences in FVC, FEV1 and DLCOcorr/VA by HTLV status. For DLCOcorr, HTLV-I and HTLV-II subjects had slightly lower values than seronegatives, but neither difference was statistically significant after adjustment for confounding.

CONCLUSIONS

There was no difference in measured pulmonary function and diffusing capacity in generally healthy HTLV-I and HTLV-II subjects compared to seronegatives. These results suggest that previously described HTLV-associated abnormalities in bronchoalveolar cells and fluid may not affect pulmonary function.

Chemokine synthesis and cellular inflammatory changes in lungs of mice bearing p40tax of human T-lymphotropic virus type 1

To elucidate the pathogenic mechanisms of human T-lymphotropic virus type 1 (HTLV-1)-associated lung inflammation, we conducted a histopathological and molecular analysis study using transgenic mice bearing pX region of this virus. In these mice, accumulations of inflammatory cells consisting mainly of lymphocytes were present in peribronchiolar and perivascular areas and alveolar septa, while control littermate mice did not show such changes. In situ hybridization showed that the anatomic distribution of p40tax mRNA was similar to that of inflammatory cells, typically in peribronchiolar areas and to a lesser extent in perivascular and alveolar septa. Inflammatory cytokines, including IL-1beta, tumour necrosis factor-alpha and interferon-gamma, and several chemokines, such as monocyte chemotactic protein-1 (MCP-1), RANTES, macrophage inflammatory protein-1alpha (MIP-1alpha) and IP-10, were detected in lungs of transgenic mice but not control mice. Semiquantitative analysis using reverse transcription-polymerase chain reaction showed a significant correlation between MCP-1 mRNA expression and p40tax mRNA, but not with other chemokines. The gene expression of the above chemokines, with the exception of MIP-1alpha, correlated with the severity of histopathological changes in the lung. Considered together, our results suggested that p40tax synthesis may be involved in the development of lung lesions caused by HTLV-1 through the induction of local production of chemokines.