[Chronic lung allograft dysfunction in 2022, past and updates]

INTRODUCTION

While short-term results of lung transplantation have improved considerably, long-term survival remains below that achieved for other solid organ transplants.

CURRENT KNOWLEDGE

The main cause of late mortality is chronic lung allograft dysfunction (CLAD), which affects nearly half of the recipients 5 years after transplantation. Immunological and non-immune risk factors have been identified. These factors activate the innate and adaptive immune system, leading to lesional and altered wound-healing processes, which result in fibrosis affecting the small airways or interstitial tissue. Several phenotypes of CLAD have been identified based on respiratory function and imaging pattern. Aside from retransplantation, which is possible for only small number of patients, no treatment can reverse the CLAD process.

PERSPECTIVES

Current therapeutic research is focused on anti-fibrotic treatments and photopheresis. Basic research has identified numerous biomarkers that could prove to be relevant as therapeutic targets.

CONCLUSION

While the pathophysiological mechanisms of CLAD are better understood than before, a major therapeutic challenge remains.

TLR3 promotes MMP-9 production in primary human airway epithelial cells through Wnt/β-catenin signaling

Background

Airway epithelial cells (AEC) act as the first line of defence in case of lung infections. They constitute a physical barrier against pathogens and they participate in the initiation of the immune response. Yet, the modalities of pathogen recognition by AEC and the consequences on the epithelial barrier remain poorly documented.

Method

We investigated the response of primary human AEC to viral (polyinosinic-polycytidylic acid, poly(I:C)) and bacterial (lipopolysaccharide, LPS) stimulations in combination with the lung remodeling factor Transforming Growth Factor-β (TGF-β).

Results

We showed a strong production of pro-inflammatory cytokines (Interleukin (IL)-6, Tumor Necrosis Factor α, TNFα) or chemokines (CCL2, CCL3, CCL4, CXCL10, CXCL11) by AEC stimulated with poly(I:C). Cytokine and chemokine production, except CXCL10, was Toll Like Receptor (TLR)-3 dependent and although they express TLR4, we found no cytokine production after LPS stimulation. Poly(I:C), but not LPS, synergised with TGF-β for the production of matrix metalloproteinase-9 (MMP-9) and fibronectin. Mechanistic analyses suggest the secretion of Wnt ligands by AEC along with a degradation of the cellular junctions after poly(I:C) exposure, leading to the release of β-catenin from the cell membrane and stimulation of the Wnt/β-catenin pathway.

Conclusion

Our results highlight the cross talk between TGF-β and TLR signaling in bronchial epithelium and its impact on the remodeling process.

Electronic supplementary material

The online version of this article (10.1186/s12931-017-0690-y) contains supplementary material, which is available to authorized users.

T Cells Promote Bronchial Epithelial Cell Secretion of Matrix Metalloproteinase-9 via a C-C Chemokine Receptor Type 2 Pathway: Implications for Chronic Lung Allograft Dysfunction

Chronic lung allograft dysfunction (CLAD) is the major limitation of long-term survival after lung transplantation. CLAD manifests as bronchiolitis obliterans syndrome (BOS) or restrictive allograft syndrome (RAS). Alloimmune reactions and epithelial-to-mesenchymal transition have been suggested in BOS. However, little is known regarding the role of allogenicity in epithelial cell differentiation. Primary human bronchial epithelial cells (BECs) were treated with activated T cells in the presence or absence of transforming growth factor (TGF)-β. The expression of epithelial and mesenchymal markers was investigated. The secretion of inflammatory cytokines and matrix metalloproteinase (MMP)-9 was measured in culture supernatants and in plasma from lung transplant recipients (LTRs): 49 stable, 29 with BOS, and 16 with RAS. We demonstrated that C-C motif chemokine 2 secreted by T cells supports TGF-β-induced MMP-9 production by BECs after binding to C-C chemokine receptor type 2. Longitudinal investigation in LTRs revealed a rise in plasma MMP-9 before CLAD onset. Multivariate analysis showed that plasma MMP-9 was independently associated with BOS (odds ratio [OR] = 6.19, p = 0.002) or RAS (OR = 3.9, p = 0.024) and predicted the occurrence of CLAD 12 months before the functional diagnosis. Thus, immune cells support airway remodeling through the production of MMP-9. Plasma MMP-9 is a potential predictive biomarker of CLAD.

Nanocrystals of Fe(phen)2(NCS)2 and the size-dependent spin-crossover characteristics

We describe the preparation of nano- and microcrystals of the Fe(phen)₂(NCS)₂ spin-crossover prototypical compound based on the solvent-assisted technique applied to an ionic and soluble precursor and analyze the size-dependent characteristics of the thermal spin-crossover.

[Quality standards for ultrasonographic assessment of peripheral vascular malformations and vascular tumors. Report of the French Society for Vascular Medicine]

THE QUALITY STANDARDS OF THE FRENCH SOCIETY OF VASCULAR MEDICINE FOR THE ULTRASONOGRAPHIC ASSESSMENT OF VASCULAR MALFORMATIONS ARE BASED ON THE TWO FOLLOWING REQUIREMENTS: Technical know-how: mastering the use of ultrasound devices and the method of examination. Medical know-how: ability to adapt the methods and scope of the examination to its clinical indication and purpose, and to rationally analyze and interpret its results. AIMS OF THE QUALITY STANDARDS: To describe an optimal method of examination in relation to the clinical question and hypothesis. To achieve consistent practice, methods, glossary, and reporting. To provide good practice reference points, and promote a high-quality process. ITEMS OF THE QUALITY STANDARDS: The three levels of examination; their clinical indications and goals. The reference standard examination (level 2), its variants according to clinical needs. The minimal content of the examination report; the letter to the referring physician (synthesis, conclusion and proposal for further investigation and/or therapeutic management). Commented glossary (anatomy, hemodynamics, semiology). Technical bases. Settings and use of ultrasound devices. Here, we discuss the methods of using ultrasonography for the assessment of peripheral vascular malformations and tumors.

Structure and magnetic properties of the hybrid system copper(II) mu2-2,2'-bipyridine-3-carboxylate-N,N':O-mu2-phosphate-O,O'

The title compound [Cu(PO4H2)(C11H7N2O2)]n presents antiferromagnetic behavior. It has a polymeric one-dimensional structure in which the elemental links are tetranuclear units and the doubly protonated phosphates and the bipyridinemonocarboxylates act in a bridging mode. The magnetic behavior is described using an alternating chain model, with J = -3.32 cm (-1), alpha = 0.7, and g = 2.05.

Giant aneurysm of the splenic artery--a case report

Giant aneurysms of the splenic artery larger than 10 cm are rare. The size of splenic aneurysms rarely exceeds 3 cm. Aneurysms that are often symptomatic because of their size must be treated rapidly before rupture. An etiologic and diagnostic evaluation with computed tomography and selective angiography of the visceral arteries is essential before treatment. Operative indication is imperative for these aneurysms. Their mass with portal compression and dense adhesions to adjacent organs allow only aneurysmal exclusion by proximal and distal ligation with preservation of the spleen. The control of the proximal splenic artery is often difficult, justifying the choice of the surgical access. A case of surgically treated giant splenic artery aneurysm associated with right benign renal lesion is presented with a review of the literature on this subject.

[Radionuclide ejection fraction at rest and in exercise in chronic aortic insufficiency. Pre- and postoperative study in asymptomatic or paucisymptomatic patients]

Twenty patients (17 men and 3 women: average age 50 +/- 14 years) with asymptomatic or paucisymptomatic aortic regurgitation were studied to compare the values of radionuclide left ventricular ejection fraction (EF) at rest and on exercise before (1) and 6 +/- 1 months (2) and 5.7 +/- 1.1 years (3) after surgery. The resting EF was similar at all three examinations: 53 +/- 8 (1); 57 +/- 8 (2); 55 +/- 16 (3). However, it increased significantly on exercise from 40 +/- 10 (1) to 54 +/- 12 (2) (p < 0.001) and to 52 +/- 20 (3) (p = 0.036 versus 1). In the 7 patients with resting EF greater than 55 before surgery, there was no postoperative improvement: 61 +/- 6 (1); 61 +/- 5 (2); 65 +/- 9 (3). However, the exercise EF increased from 44 +/- 13 (1) to 55 +/- 17 (2) and 69 +/- 11 (3) (p = 0.004 vs 1). In 13 patients with resting EF < 55%, the value increased in the early postoperative phase but not later: resting: 49 +/- 5 (1); 55 +/- 8 (2) (p = 0.04); 49 +/- 17 (3) (NS vs 1); effort: 38 +/- 7 (1); 54 +/- 10 (2) (p < 0.001); 40 +/- 16 (3) (NS vs 1). Left ventricular systolic function only returns to normal and exercise after surgery in patients with resting preoperative EF > or = 55%, but nothing indicates that this normalisation is an absolute condition for a successful surgical result in aortic insufficiency in terms of survival and quality of life.

Anomalous origin of left coronary artery from the pulmonary artery: evolution of left ventricular function and perfusion after surgery in a 44-year-old man

Anomalous origin of left coronary vessel from the pulmonary artery is an almost universally fatal form of congenital heart disease unless appropriate corrective surgery is performed at an early age. A case was diagnosed in a symptomatic 44-year-old man who presented an impairment of systolic left ventricular function. The abnormality was successfully treated with ligation of the left coronary artery combined with left internal mammary artery anastomosis. Left ventricular function improved dramatically six months after surgery, both at rest and during exercise. Such an evolution suggests that surgery may be indicated not only in infants but also in adults with this congenital heart abnormality.

Mortality of demented patients in a geriatric institution

A group of 237 elderly patients with dementia of Alzheimer type (DAT) or multi-infarct dementia (MID) was randomly selected in a large geriatric institution in Milan. Mean age of the sample was 78.9 years, 160 (67.5%) were DAT patients and 77 (32.5%) were MID patients. Half of the sample had low levels of autonomy and after 4 years 183 (77.2%) patients were dead. Predictors of mortality, according to a univariate analysis, were age, level of autonomy and type of diagnosis (DAT vs. MID). Mortality rate after 4 years was significantly higher (p less than 0.001) in DAT (86.9%) than in MID (57.1%) patients.

[Course of the radionuclide left ventricular ejection fraction at rest and during exercise in surgically treated asymptomatic chronic aortic insufficiency]

In order to preserve left ventricular (LV) function, aortic valve replacement may be contemplated in asymptomatic patients with aortic regurgitation when LV dilatation and dysfunction are not too advanced. Our study involved 10 asymptomatic patients with severe, isolated and pure aortic regurgitation. Before, and 6 months after the operation, the LV ejection fraction (LVEF) was measured at rest and during exercise on an ergometric bicycle by radionuclide angiography (multigated technique). Mean preoperative values were: age 52 +/- 14 years; cardiothoracic ratio 0.55 +/- 0.04; end-diastolic LV diameter 69 +/- 9 mm; end systolic LV diameter 47 +/- 7 mm; LV fibre shortening fraction 0.31 +/- 0.03; LVEF 0.55 +/- 0.10 at rest and 0.41 +/- 0.13 at exercise. After surgery, the cardiothoracic ratio value (0.51 +/- 0.03) and the LVEF value at rest (0.60 +/- 0.07) were not significantly different from the corresponding preoperative values, but the LVEF value during exercise was significantly increased (0.58 +/- 0.11, p less than 0.001). Among the 9 patients who before surgery showed a fall in LVEF at exercise, after surgery 5 had a rise (group B) and 4 had a fall (group A) in LVEF at exercise. Before surgery, group A patients had greater LV diameters than group B patients: end-diastolic diameter 76 +/- 6 mm vs 63 +/- 9 mm; end-systolic diameter 53 +/- 4 mm vs 43 +/- 7 mm (p = 0.07). These diameters were the only variables that predicted the postoperative changes in LVEF at exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

[Enalapril versus digoxin in chronic congestive cardiac failure. Study of variation of the left ventricular ejection fraction determined by radio-isotopic angioscintigraphy at rest and during exertion]

The effects of enalapril were evaluated in a double-blind, controlled study during 8 weeks, in patients with stable, congestive chronic cardiac insufficiency (functional classification II and III of the NYHA), in sinus rhythm, treated with digitalis and diuretics. 20 patients were randomly divided in two groups: one group continuing the digoxin (group A: 10 patients) and one group where enalapril was substituted for digoxin (group B: 10 patients). Patients from group B presented less clinical aggravation during the study. The left ventricular stroke volume (SV) is significantly decreased in group B at rest (0.21 +/- 0.06 at 50; 0.18 +/- 0.04 at 54; p less than 0.05), while it remained stable during stress. No variations of the SVs were noted at rest and during stress in group A. Considering its favorable clinical effects and after evaluation of its longterm side effects, enalapril may be an acceptable alternative to digitalis in cardiac insufficiency with sinus rhythm, except in patients for whom a drop in the systemic blood pressure or an increased kaliemia or creatininemia, could be potentially harmful.

[Left ventricular function in chronic asymptomatic aortic insufficiency. Angioscintographic study]

More accurate information is needed on the usefulness of radionuclide angiography performed during exercise for the assessment of left ventricular function in chronic aortic regurgitation and on its value compared with echocardiography. Between January, 1985 and January, 1988, we studied 23 asymptomatic patients presenting with severe, isolated and pure aortic regurgitation. Nine patients who were not operated upon during that period (group N) had the following characteristics: age 39.4 +/- 12.3 years, left ventricular end-diastolic diameter 67.3 +/- 4.7 mm, left ventricular end-systolic diameter 43.4 +/- 3.2 mm, left ventricular fibre shortening fraction 0.36 +/- 0.05, left ventricular radionuclide ejection fraction 0.67 +/- 0.10 at rest and 0.66 +/- 0.09 during maximum exercise. Compared with the values obtained in 8 controls of the same age (ejection fraction 0.65 +/- 0.07, p less than 0.05, at rest and 0.76 +/- 0.09, p less than 0.05, during maximum exercise), the behaviour of group N patients during exercise was perturbed. Fourteen patients who underwent surgery presented with the following characteristics: age 53.3 +/- 13.3 years (p less than 0.05), left ventricular end-diastolic diameter 71.4 +/- 8.7 mm (p less than 0.05), left ventricular end-systolic diameter 49.4 +/- 6.5 mm (p less than 0.05), fibre shortening fraction 0.31 +/- 0.03 (p less than 0.01), ejection fraction 0.53 +/- 0.08 at rest (p less than 0.001) and 0.40 +/- 0.08 during maximum exercise (p less than 0.001). These results suggest that radionuclide angiography performed during exercise is effective in the early detection and accurate evaluation of myocardial dysfunction in patients with chronic aortic regurgitation at the asymptomatic stage.(ABSTRACT TRUNCATED AT 250 WORDS)

[Prognosis of surgically corrected chronic aortic insufficiency]

It is difficult to determine the surgical indications of asymptomatic chronic aortic regurgitation (AR). This study was undertaken in 205 patients with pure AR, operated between 1970 and 1982: 136 patients were symptomatic (Classes III and IV of the NYHA, +/- cardiac failure +/- angina, mean age: 49.5 years). Sixty nine asymptomatic patients (Classes I and II of the NYHA without cardiac failure or angina, mean age: 42 years). The prognostic value of 58 variables was studied in these two groups. The mortality during the first postoperative month was 14% in the symptomatic patients and the 5 year survival rate was 68.7%; this was significantly lower in patients with ECG changes of systolic left greater than or equal to ventricular overload, with radiological cardiomegaly (cardiotolerance index 0.60) with calcific aortic valve disease, with raised arterio-venous difference and/or low cardiac output, and with a low ejection fraction. In the asymptomatic group, the hospital mortality was zero and the 5 year survival rate 86.8%. This was significantly decreased in patients with an increased PR interval and a low cardiac index. It is possible that the small number of patients did not demonstrate the predictive value of left ventricular function in asymptomatic patients (a hypothesis suggested by the causes of secondary mortality which were the same in both groups of patients).(ABSTRACT TRUNCATED AT 250 WORDS)