Search PubMed⌕ Search

Biomedical subjects

R A Stockley

Publications and source records attributed to R A Stockley.

At least 37 records · Page 2Linked to original sources
PubMed2002

Sputum chemotactic activity in chronic obstructive pulmonary disease: effect of alpha(1)-antitrypsin deficiency and the role of leukotriene B(4) and interleukin 8.

BACKGROUND: Neutrophil recruitment to the airway is thought to be an important component of continuing inflammation and progression of chronic obstructive pulmonary disease (COPD), particularly in the presence of severe alpha(1)-antitrypsin (alpha(1)-AT) deficiency. However, the chemoattractant nature of secretions from these patients has yet to be clarified. METHODS: The chemotactic activity of spontaneous sputum from patients with stable COPD, with (n=11) and without (n=11) alpha(1)-AT deficiency (PiZ), was assessed using the under-agarose assay. The contribution of leukotriene B(4) (LTB(4)) and interleukin 8 (IL-8) to the chemotactic activity was examined using an LTB(4) receptor antagonist (BIIL 315 ZW) and an IL-8 monoclonal antibody, respectively. RESULTS: Sputum neutrophil chemotactic activity (expressed as % n-formylmethionyl leucylphenylalanine (fMLP) control) was significantly higher in patients with alpha(1)-AT deficiency (mean (SE) 63.4 (8.9)% v 36.7 (5.5)%; mean difference 26.7% (95% CI 4.9 to 48.4), p<0.05). The mean (SE) contribution of both LTB(4) and IL-8 (expressed as % fMLP control) was also significantly higher in alpha(1)-AT deficient patients than in patients with COPD with normal levels of alpha(1)-AT (LTB(4): 31.9 (6.3)% v 18.0 (3.7)%; mean difference 13.9% (95% CI -1.4 to 29.1), p<0.05; IL-8: 24.1 (5.2)% v 8.1 (1.2)%; mean difference 15.9% (95% CI 4.7 to 27.2), p<0.05). When all the subjects were considered together the mean (SE) contribution of LTB(4) (expressed as % total chemotactic activity) was significantly higher than IL-8 (46.8 (3.5)% v 30.8 (4.6)%; mean difference 16.0% (95% CI 2.9 to 29.2), p<0.05). This difference was not significantly influenced by alpha(1)-AT phenotype (p=0.606). CONCLUSIONS: These results suggest that the bronchial secretions of COPD patients with alpha(1)-AT deficiency have increased neutrophil chemotactic activity. This relates to the increased levels of IL-8 and, in particular LTB(4), which accounted most of the sputum chemotactic activity in the patients with COPD as a whole. Increased chemotactic activity, together with inhibitor deficiency, may contribute to the more rapid disease progression seen in alpha(1)-AT deficiency via increased neutrophil recruitment and release of neutrophil elastase.

Chemotactic Factors↗
PubMed2002

Alpha1-antitrypsin deficiency: a report from the 2nd meeting of the Alpha One International Registry, Rapallo (Genoa, Italy), 2001.

The Alpha One International Registry is a scientific foundation established to comply with a World Health Organization recommendation to develop a multinational registry of alpha1-antitrypsin deficiency, with the aim of creating a common database of subjects recognised in a standardised way. A commitment of the Alpha One International Registry members, belonging to 15 national registries, is to meet every 2 yrs in an open scientific conference to provide a scientific and clinical update on the deficiency. The second Alpha One International Registry meeting was held in Rapallo (Genoa, Italy) on September 27th-28th, 2001, and 26 speakers provided an exhaustive overview of all aspects of alpha1-antitrypsin deficiency, including epidemiology, genetics, biochemistry, associated conditions, established and novel therapeutic options, and markers of efficacy. In the framework of a rare and often under-recognised condition, this meeting is likely to be central to improving understanding and increasing awareness of alpha1-antitrypsin deficiency.

Female↗
PubMed2001

Longitudinal changes in physiological, radiological, and health status measurements in alpha(1)-antitrypsin deficiency and factors associated with decline.

The FEV(1) declines rapidly in alpha(1)-antitrypsin deficiency (alpha(1)-ATD) but less is known about other measures of disease severity and the factors, other than smoking, that are associated with progression of emphysema. The natural history of alpha(1)-ATD was studied prospectively in 43 patients with the PiZ phenotype and emphysema at a single center over 2 yr. The mean +/- SE change in FEV(1) was -67 +/- 14 ml/yr, accompanied by a reduction in transfer factor (mean change in diffusing capacity of the lung for CO [DL(CO)] -1.07 +/- 0.21 ml/min/mm Hg/yr; p < 0.001) and lung density in the upper zones as assessed by quantitative high-resolution computed tomography (HRCT) (mean change in voxel index 2.8 +/- 0.6%/yr; p < 0.001). The decline in FEV(1) related to baseline FEV(1) (r = -0.56, p < 0.001), bronchodilator reversibility (r = 0.52, p < 0.001), and (for patients with FEV(1) > 35% predicted) exacerbation frequency (r = -0.38, p = 0.02). There was also a decline in the St. George's Respiratory Questionnaire (SGRQ) Activity score (mean change -4.3 +/- 1.2 units/yr, p < 0.001) that correlated with FEV(1) decline (r = 0.45, p = 0.002). Progression of emphysema in alpha(1)-ATD is dependent on baseline physiology and exacerbation frequency and may be detected by several different measurements of which HRCT density mask analysis and DL(CO) appear most sensitive.

Adult↗
PubMed2001

Proteases and antiproteases.

Serine proteases have been implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD) since the identification of alpha 1-antitrypsin deficiency in 1963. This inhibitor efficiently inactivates several enzymes released by activated neutrophils including neutrophil elastase, cathepsin G and proteinase 3, all of which have been shown to generate features of COPD in animal models. Recent studies have identified the mechanisms of enzyme release from activated neutrophils and indicate that the concentrations are usually two orders of magnitude above that of normal alpha 1-antitrypsin. This results in an area of obligate proteolysis in the immediate vicinity of a migrating neutrophil. The area is greatly enlarged in alpha 1-antitrypsin deficiency explaining the increased susceptibility of such patients to develop lung damage. The migration into and activation of neutrophils in the lung is likely to be a major determinant of the development of COPD. Understanding the processes has important implications for the design of new therapeutic strategies.

Animals↗
PubMed2001

Relationship between airway inflammation and the frequency of exacerbations in patients with smoking related COPD.

BACKGROUND: Patients with more frequent exacerbations of chronic obstructive pulmonary disease (COPD) may have increased bronchial inflammation. Airway inflammation was measured in patients who had been thoroughly investigated with full pulmonary function testing, thoracic HRCT scanning, and sputum microbiology to examine further the relationship between exacerbation frequency and bronchial inflammation. METHODS: Airway inflammation (spontaneous sputum sol phase myeloperoxidase (MPO), elastase, leukotriene (LT)B(4), interleukin (IL)-8, secretory leukoprotenase inhibitor (SLPI), protein leakage) and serum levels of C reactive protein (CRP) were compared in 40 patients with stable, smoking related COPD, divided into those with frequent (> or =3/year) or infrequent (< or =2/year) exacerbations according to the number of primary care consultations during the preceding year. The comparisons were repeated after excluding eight otherwise clinically indistinguishable patients who had tubular bronchiectasis on the HRCT scan. RESULTS: Patients with frequent (n=12) and infrequent (n=28) exacerbations were indistinguishable in terms of their clinical, pulmonary function, and sputum characteristics, CRP concentrations, and all of their bronchial inflammatory parameters (p>0.05). The patients without evidence of tubular bronchiectasis (n=32) were equally well matched but the sputum concentrations of SLPI were significantly lower in the frequent exacerbators (n=8) in this subset analysis (p<0.05). CONCLUSIONS: There are several clinical features that directly influence bronchial inflammation in COPD. When these were carefully controlled for, patients with more frequent reported exacerbations had lower sputum concentrations of SLPI. This important antiproteinase is also known to possess antibacterial and antiviral activity. Further studies are required into the nature of recurrent exacerbations and, in particular, the regulation and role of SLPI in affected individuals.

Aged↗
PubMed2001

Symptom resolution assessed using a patient directed diary card during treatment of acute exacerbations of chronic bronchitis.

BACKGROUND: Acute exacerbations of chronic bronchitis are common and the presenting symptoms vary, although it is not clear how this should influence management. From a health care perspective, an understanding of the speed of symptom resolution is of importance to determine the success of treatment or when a change is indicated because of treatment failure. METHODS: The response of 63 patients treated at home for exacerbations of chronic bronchitis was assessed using a patient directed diary card incorporating sputum characteristics and symptoms. Treatment was given according to the nature of the sputum at presentation; patients with purulent sputum received an antibiotic for 5 or 10 days (randomised, double blind) whereas patients with mucoid sputum received high dose inhaled steroid or placebo for 14 days (randomised, double blind). RESULTS: The mean (SE) total diary card score at presentation was significantly higher in the purulent group than in the mucoid group (19.7 (0.9) v 16.3 (0.9); mean difference -3.4 (95% CI -6.1 to -0.7), p<0.05). In the purulent group sputum colour and volume improved rapidly and in both groups the mean (SE) total diary card score had improved by the fifth day of treatment to 13.0 (0.7) in the purulent group (mean difference -6.6 (95% CI -8.8 to -4.4), p<0.001) and 14.6 (0.8) in the mucoid group (mean difference -1.7 (95% CI -4.0 to 0.8), p<0.05), which was no longer significantly different from the stable state. Diary card scores did not differ significantly between patients who received antibiotics for 5 or 10 days in the purulent group or between patients who received inhaled fluticasone or placebo in the mucoid group. CONCLUSIONS: Exacerbations of chronic bronchitis associated with purulent sputum have significantly worse symptoms at presentation than those with mucoid sputum. In both groups these symptoms resolve rapidly so that by the fifth day of treatment they are no different from the stable state. No significant effect was found on symptom resolution of antibiotic duration (5 v 10 days) in the purulent group or of inhaled fluticasone in the mucoid group, which resolved without antibiotics. Larger numbers may be required to demonstrate a statistically (if not clinically) significant difference.

Acute Disease↗
PubMed2001

Assessment of airway neutrophils by sputum colour: correlation with airways inflammation.

BACKGROUND: Airway inflammation, with recruitment of neutrophils to the airway lumen, results in purulent secretions and a variety of potential adverse consequences for patients with chronic bronchitis and bronchiectasis. We hypothesised that gradations of sputum colour would correlate directly with the myeloperoxidase content of sputum and with various other indicators of the activity and consequences of bronchial diseases. METHODS: To test this hypothesis, we quantified sputum colour by reference to a sensitive nine point colour chart and correlated this assessment with indices of a number of inflammatory mediators in sputum. RESULTS: The results indicate that standardised visual measurements of sputum colour correlated strongly with myeloperoxidase, interleukin 8, leucocyte elastase (both activity and total quantity), sputum volume, protein leak, and secretory leucocyte proteinase inhibitor (p<0.001 for all). In addition, there was a strong direct correlation between leucocyte elastase and both myeloperoxidase (p<0.003) and sputum volume (p<0.001), but a strong negative correlation with secretory leucocyte proteinase inhibitor (p<0.001). CONCLUSIONS: These results indicate that sputum colour graded visually relates to the activity of the underlying markers of bronchial inflammation. The results of this simple visual analysis of sputum provides guidance concerning underlying inflammation and its damaging potential. It also provides a useful scientific tool for improving the monitoring of chronic airways diseases and response to treatment.

Biomarkers↗
PubMed2001

Exercise capacity predicts health status in alpha(1)-antitrypsin deficiency.

Resting lung function is only weakly related to health status in chronic obstructive pulmonary disease, reflecting the multifactorial causes of impairment and the heterogeneous nature of the condition. The current study examined whether density mask analysis of high-resolution computed tomography (HRCT) or exercise capacity were better surrogates for health status in a well-defined, homogeneous group of patients with alpha(1)-antitrypsin deficiency (PiZ). Twenty-nine patients with predominantly lower zone emphysema on HRCT were studied. Exercise was assessed by incremental treadmill (V O(2) peak) and shuttle walking tests (ISWT) and health status by the St. George's Respiratory Questionnaire (SGRQ) and SF-36. Although lower zone expiratory HRCT was related to exercise capacity (rho = -0.64 and -0.63 for V O(2) peak and ISWT, respectively, p < 0.001), multiple regression analysis suggested that FEV(1) was a marginally better predictor (rho = -0.64 and -0.65, p < 0.001). HRCT also related significantly to health status (rho = -0.37 for SGRQ activity, p < 0.05), although again FEV(1) showed a stronger relationship (rho = -0.43, p = 0.01). However, exercise capacity was the best predictor of health status with the ISWT accounting for up to 55% of the variability seen in SGRQ total and up to 53% of the SF-36 domain scores (physical functioning). Although both HRCT and lung function relate to health status, exercise capacity is the best predictor of patients disability in these patients with predominantly lower zone emphysema.

Exercise Test↗
PubMed2001

High-resolution computed tomography scanning in alpha1-antitrypsin deficiency: relationship to lung function and health status.

The development of computed tomography (CT) has enabled emphysema to be assessed noninvasively. Objective quantification of lung density correlates well with lung function in patients with chronic obstructive pulmonary disease and has been shown to be a sensitive tool for monitoring disease progression. In order to determine the clinical impact of changes seen on high-resolution computed tomography (HRCT), the relationship between the objective quantification of emphysema on HRCT, lung function and health status in 111 patients with alpha1-antitrypsin deficiency was examined (PiZ). The degree of HRCT scan abnormality correlated well (p<0.001 for all comparisons) with forced expiratory volume in one second (r = -0.60- -0.75), specific airway conductance (r = -0.67-0.76), residual volume/total lung capacity (r = 0.46-0.58) and transfer factor of the lung for carbon monoxide (r = -0.64- -0.81). In addition, the CT scans correlated (p<0.001) with health status as assessed by the St. George's Respiratory Questionnaire (SGRQ total: r = -0.38-0.50) and the Short-Form health survey (e.g. physical functioning: r = -0.39-0.54). In summary, other workers have shown high-resolution computed tomography to be a sensitive indicator of disease progression. This study confirms the relationship between high-resolution computed tomography and lung physiology, and suggests the relationship is even stronger in patients with predominantly lower zone pan-lobular emphysema than in usual chronic obstructive pulmonary disease. High-resolution computed tomography also relates to patients disability and impairment as defined by health status questionnaires and, therefore, should be considered as an alternative outcome measure particularly in alpha1-antitrypsin deficiency.

Adult↗
PubMed2001

Alpha-1-antitrypsin genotyping with mouthwash specimens.

Alpha1-antitrypsin (alpha1-AT) deficiency is diagnosed as a two-stage procedure (concentration and phenotype). However the latter does not provide clues to the presence of null genes without family studies and obtaining blood from patients at a distance often proves difficult. The aim of the study was to assess the feasibility of genotyping alpha1-AT using buccal cells. Mouthwash specimens were sent by 84 patients (with a variety of phenotypes of alpha1-antitrypsin) through the post. Deoxyribonucleic acid (DNA) was isolated from buccal cells in each sample and subjected to polymerase chain reaction (PCR) using a genotyping kit to detect the S and Z alleles. Eighty-three of 84 samples received were suitable for amplification. The specific primers successfully identified the S and Z alleles in each case. However, five of the 35 samples obtained from patients thought to be Z allele homozygotes were found to be heterozygotes for another severe deficiency allele. These data confirm the feasibility of "at distance" testing for alpha1-antitrypsin deficiency alleles using buccal cells from mouthwash samples. The results raise the possibility that other deficiency alleles are more common than has previously been suspected.

Feasibility Studies↗
PubMed2001

Changes in bronchial inflammation during acute exacerbations of chronic bronchitis.

There are little data describing noncellular changes in bronchial inflammation during exacerbations of chronic bronchitis. The relationship between sputum colour and airway inflammation at presentation has been assessed during an exacerbation in patients with chronic bronchitis and a primary care diagnosis of chronic obstructive pulmonary disease. Sputum myeloperoxidase, neutrophil elastase, leukotriene B4 (LTB4), interleukin-8 (IL-8), sol:serum albumin ratio and serum C-reactive protein were measured in patients presenting with an exacerbation and mucoid (n = 27) or purulent sputum (n = 42). Mucoid exacerbations were associated with little bronchial or systemic inflammation at presentation, and sputum bacteriology was similar to that obtained in the stable state. Purulent exacerbations were associated with marked bronchial and systemic inflammation (p < 0.025 for all features) and positive sputum cultures (90%). Resolution was related to a significant reduction in LTB4 (p < 0.01), but no change in IL-8, suggesting that LTB4 may be more important in neutrophil recruitment in these mild, purulent exacerbations. In the stable state, IL-8 remained higher in patients who had experienced a purulent exacerbation (2p < 0.02). The presented results indicate that exacerbations of chronic bronchitis, defined by sputum colour, differ in the degree of bronchial and systemic inflammation. Purulent exacerbations are related to bacterial infection, and are associated with increased neutrophilic inflammation and increased leukotriene B4 concentrations.

Acute Disease↗
PubMed2000

Migration of CD18-deficient neutrophils in vitro: evidence for a CD18-independent pathway induced by IL-8.

Neutrophils isolated from a child with severe leukocyte adhesion deficiency 1 (LAD1) had a complete absence of expression of the CD11/CD18 beta2 integrin family of adhesion molecules, and were shown to be deficient in the in vitro adhesion and migration properties. However, we found that interleukin-8 (IL8), a potent chemoattractant for neutrophils, and sputum sol phase induced these LAD1 neutrophils to migrate through an endothelial cell layer in vitro, and confirmed that this migration was CD18-independent. These findings add to evidence of CD18-independent mechanisms of neutrophil recruitment, in particular neutrophil infiltration into the lungs, where IL8 may be an important recruitment factor.

Antibodies↗
PubMed2000

Phenotypic changes in neutrophils related to anti-inflammatory therapy.

Previous work from the group has shown that non-steroidal anti-inflammatory agents given to volunteers and patients inhibit PMN function possibly by affecting the developing neutrophil during the differentiation process. In this study indomethacin treatment in vivo reduced neutrophil chemotaxis and proteolytic degradation of fibronectin, with a maximal effect after 14 days. Stimulated neutrophil adherence to fibronectin was also reduced but this was not due to quantitative changes in beta(2) integrin expression or function. L-Selectin expression on resting and stimulated neutrophils was increased after 14 days and there was a small decrease in plasma levels of soluble L-selectin. These effects, however, could not be reproduced by treatment of neutrophils with indomethacin in vitro, suggesting they are due to effects on differentiating/maturing PMNs. In an attempt to interpret these changes, studies were performed with dexamethasone, which is known to alter neutrophil function and kinetics. Dexamethasone treatment reduced chemotaxis and increased superoxide generation after 1 day and was associated with increased expression of activated beta(2) integrins and reduced L-selectin expression on resting neutrophils. This suggests the appearance of mainly 'activated' cells as a result of demargination and indicates that the effects of indomethacin are distinctive and not related to changes in compartmentalisation.

Adult↗
PubMed2000

Association between airway bacterial load and markers of airway inflammation in patients with stable chronic bronchitis.

PURPOSE: Viable bacteria are often isolated from airway secretions in clinically stable patients with chronic bronchitis. We hypothesized that the number of organisms and bacterial species might be important modulators of airway inflammation. SUBJECTS AND METHODS: We performed quantitative sputum cultures in 160 stable patients [55 with chronic obstructive pulmonary disease (COPD) and normal serum alpha(1)-antitrypsin levels, 62 with COPD and severe alpha(1)-antitrypsin deficiency (PiZ), and 43 with idiopathic bronchiectasis]. The results were related to several indicators of the mechanisms and severity of airway inflammation. RESULTS: Airway bacterial load correlated with sputum myeloperoxidase level, an indirect measure of neutrophil activation and number (r = 0.50, P<0. 001); sputum neutrophil chemoattractants [interleukin-8 level (r = 0. 68, P<0.001) and leukotriene B4 level (r = 0.53, P<0.001)]; sputum leukocyte elastase activity (r = 0.55, P<0.001); and albumin leakage from serum to sputum (r = 0.26, P<0.01). Markers of inflammation increased at bacterial loads of 10(6) to 10(7) colony-forming units per milliliter, and increased progressively with increasing bacterial load. For example, the median (interquartile range) sputum myeloperoxidase level was 0.3 U/mL (0.1 to 0.5 U/mL) for patients who were not colonized or who had mixed normal oropharyngeal flora alone; 0.5 U/mL (0.2 to 0.7 U/mL) for patients with 10(5) to 10(6) colony-forming units per milliliter (P = 0.07); 0.5 U/mL (0.3 to 1.2 U/mL) for patients with 10(6) to 10(7) colony-forming units per milliliter (P<0.01); 0.7 U/mL (0.3 to 1.2 U/mL) for patients with 10(7) to 10(8) colony-forming units per milliliter (P <0.005); and 2.4 U/mL (0.7 to 4.8 U/mL) for patients with 10(8) or greater colony-forming units per milliliter (P<0.0001). The bacterial species influenced airway inflammation; for example, sputum myeloperoxidase activity was greater (P<0.005) in patients colonized with Pseudomonas aeruginosa [median 32 U/mL (interquartile range, 20 to 65 U/mL)] than those colonized with nontypeable Hemophilus influenzae [4 U/mL (2 to 31 U/mL)], which in turn was greater (P = 0.01) than among those colonized with Moraxella catarrhalis [1.1 U/mL (0.6 to 1.8 U/mL)]. We did not find a relation between bacterial load and lung function. CONCLUSIONS: The bacterial load and species contribute to airway inflammation in patients with stable chronic bronchitis. Further studies are required to determine the consequences of bacterial colonization on patient morbidity and decline in lung function.

Aged↗
PubMed2000

MEKC of desmosine and isodesmosine in urine of chronic destructive lung disease patients.

Degradation of extracellular matrix components is central to many pathological features of chronic destructive lung disorders. Desmosine and isodesmosine are elastin-derived cross-linked amino acids whose urine levels are considered representative of elastin breakdown. The aim of this study was to apply a novel methodology, based on high-performance capillary electrophoresis, to the quantification of desmosine and isodesmosine in 11 patients with stable chronic obstructive pulmonary disease (COPD), 10 with an exacerbation of COPD, nine with alpha1-antitrypsin deficiency, 13 with bronchiectasis, and 11 adults with cystic fibrosis, in comparison to 24 controls. It was found that, in patients with stable COPD, urinary desmosine levels were higher than in controls (p=0.03), but lower than in COPD subjects with an exacerbation (p< or =0.05). The highest desmosine levels were found in subjects with alpha1-antitrypsin deficiency, bronchiectasis and cystic fibrosis (p<0.001 versus stable COPD). In a short-term longitudinal study, five stable COPD patients showed a constant rate of desmosine excretion (mean coefficient of variation <8% over three consecutive days). In conclusion, the present method is simple and suitable for the determination of elastin-derived cross-linked amino acid excretion in urine, giving results similar to those obtained using other separation methods. In addition, evidence is presented that urinary desmosine excretion is increased in conditions characterized by airway inflammation, such as exacerbations of chronic obstructive pulmonary disease, bronchiectasis and cystic fibrosis. Results obtained in subjects with alphal-antitrypsin deficiency suggest that this method might be used to evaluate the putative efficacy of replacement therapy.

Adult↗
PubMed2000

Bronchial inflammation in acute bacterial exacerbations of chronic bronchitis: the role of leukotriene B4.

Neutrophils recruited to the airways in chronic obstructive pulmonary disease (COPD) are thought to mediate tissue destruction. Neutrophil recruitment is increased during bacterial exacerbations. The inflammatory process was studied in patients with an acute exacerbation of COPD in order to ascertain the role of leukotriene B4 (LTB4). The sputum of eight subjects with a bacterial exacerbation of COPD was analysed for neutrophil products (myeloperoxidase, elastase) and chemoattractants (interleukin-8 (IL-8) and LTB4). The contribution of LTB4 to the chemotactic activity of the sputum sol phase was determined using the LTB4 receptor antagonist LY293111. The concentrations of the serum acute phase proteins alpha1-proteinase inhibitor, alpha1-antichymotrypsin and C-reactive protein were measured. All patients received appropriate broad-spectrum antibiotic treatment for 7-14 days. Initially, the sputum myeloperoxidase activity was high, indicating neutrophil influx; this was associated with high levels of IL-8 and LTB4. All these concentrations fell with treatment (p<0.01). The chemotactic activity of the sputum was raised on presentation and fell with treatment (p<0.01). LTB4 contributed approximately 30% of the total chemotactic activity on presentation; this diminished with therapy. All acute phase proteins were raised on presentation and fell with therapy (p<0.01). These findings suggest that leukotriene B4 contributes to neutrophil influx into the airway in chronic obstructive pulmonary disease and may influence disease progression.

Acute-Phase Proteins↗