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T A Out

Publications and source records attributed to T A Out.

At least 19 recordsLinked to original sources

Children with chronic renal failure have reduced numbers of memory B cells.

Reduced serum IgG and subclass levels have been demonstrated in children with chronic renal failure. To study possible causes of this reduction, we analysed B cell subset composition, T helper cell frequencies and immunoglobulin (Ig) production capacity in vitro in children with chronic renal failure, with or without dialysis treatment. B cell subsets were characterized by determining CD27, IgM, IgD and CD5 expression within the CD19(+) population. Intracellular expression of interferon (IFN)-gamma, interleukin (IL)-2 and IL-4 in PMA/ionomycin-stimulated peripheral blood mononuclear cells (PBMC) was used to evaluate T helper frequencies. The capacity of B cells to secrete Ig in vitro was determined by measuring IgG(1), IgG(2) and IgM in culture supernatants of anti-CD2/CD28 monoclonal antibody (MoAb)- or SAC/IL-2-stimulated PBMC. Memory B cell numbers (identified as percentage or absolute number of CD19(+) IgM-IgD- or CD19(+)CD27(+) lymphocytes) were lower in children treated with haemodialysis (HD), peritoneal dialysis (PD) and children with chronic renal failure before starting dialysis treatment (CRF) compared to healthy controls (HC) (P < 0.05). Compared with HC, CD5(+) (naive) B cells were reduced in HD-treated patients but not for PD or for children with chronic renal failure before starting dialysis treatment (CRF). No significant differences in CD4(+) T helper cell subsets were found between the groups. However, CRF children had a higher percentage of IFN-gamma producing CD8(+) T lymphocytes compared to HC (P = 0.02). Finally, IgG(1), IgG(2) and IgM production in vitro was similar in the four groups. In conclusion, significantly lower numbers of memory type B cells were found in children with chronic renal failure compared to healthy controls. This reduction may contribute to the low Ig levels found in these children.

Adolescent↗

Allergen-induced bronchial inflammation in house dust mite-allergic patients with or without asthma.

BACKGROUND: It is presently unknown which factors determine the occurrence and persistence of asthma in house dust mite-allergic individuals. The level of allergen-specific IgE antibodies does not seem to be decisive for asthmatic symptoms. Moreover, levels of exposure to mite allergens do not seem to differ significantly between asthmatic and non-asthmatics individuals. AIM: It was hypothesized that the presence or absence of asthmatic symptoms in house dust mite-allergic patients is associated with quantitative or qualitative differences in the cellular bronchial inflammatory response during the late phase of the allergic reaction. This hypothesis was tested in the bronchial allergen challenge model. MATERIAL AND METHODS: Whole lung challenges with house dust mite extract were performed in 52 house dust mite-allergic subjects, of whom 26 had asthma and 26 had perennial rhinitis without asthmatic symptoms. Primary outcomes were parameters for bronchial inflammation in serial samples of induced sputum (cell differentials, eosinophil cationic protein (ECP), interleukin-8 (IL-8), myeloperoxydase (MPO)). In addition, lung function, non-specific bronchial hyper-responsiveness and serial blood samples (eosinophils and IL-5) were analysed. RESULTS: At baseline sputum eosinophils and ECP were similar in both groups but neutrophils and IL-8 were higher in asthmatics. The early bronchoconstriction after allergen challenge was similar in asthma and non-asthmatic rhinitis (median decrease in FEV1: asthma -31.7% vs. non-asthmatics -29.1%, P > 0.1). The late phase bronchoconstriction was significantly greater in asthma (median decrease in FEV1: asthma -27.6% vs. non-asthmatics -18.9%, P = 0.02). Induction of bronchial hyper-responsiveness was similar in both groups. Bronchial allergen challenge elicited significant increases in sputum eosinophils and ECP, which were indistinguishable for both groups (P > 0.1 and P = 0.07, respectively). In contrast, higher numbers of neutrophils persisted in asthma 24h after challenge and were accompanied by significant increases in IL-8 and MPO, which were absent in non-asthmatics (difference between groups P = 0.007 and P = 0.05, respectively). CONCLUSION: Allergen challenge inducedvery similar increases in eosinophils and ECP in induced sputum in allergic asthmatics and in allergic non-asthmatic patients. The difference in bronchial inflammation between asthma and non-asthmatic rhinitis appeared to be more closely related to indices for neutrophilic inflammation.

Adolescent↗

Cytokines in cervicovaginal washing fluid from patients with cervical neoplasia.

Human papillomavirus (HPV) infections play an important role in the development of cervical neoplasia. To get to a better understanding of the role of cytokines in the development of these neoplasias, we analysed the presence of various cytokines in cervicovaginal washings of healthy volunteers (n=22), cervical intraepithelial neoplasia (CIN) patients (n=63) and cervical cancer patients (n=33). IL-12p40, IL-10, TGF-beta1, TNF-alpha and IL-1beta levels were significantly higher in patients with cervical cancer than in controls and CIN patients. The levels of IFN-gamma were not different. Our data demonstrate alterations in the local cervical immune environment in cervical cancer patients. This could have important consequences for the further development of immune modulating therapies and vaccination strategies.

Adult↗

Interferon-gamma in healthy subjects: selective modulation of inflammatory mediators.

BACKGROUND: It is suggested that interferon-gamma (IFN-gamma), like other cytokines, is a mediator in the host inflammatory response, which could be of importance in the pathophysiology of sepsis. The role of IFN-gamma in human host inflammatory responses, however, has not been studied. DESIGN: In a placebo-controlled trial we studied the acute effects of IFN-gamma administration on host inflammatory mediators in healthy men: i.e. the cytokine/chemokine cascade system, acute-phase proteins, activation markers of the innate cellular immunity and coagulation/fibrinolysis parameters. RESULTS: IFN-gamma increased plasma levels of interleukin-6 (IL-6), IL-8 and IFN-gamma-inducible protein-10 (IP-10) (P < 0.05), but did not affect plasma levels of other cytokines (IL-4, IL-10, tumour necrosis factor-alpha, IL-12p40/p70). Plasma concentrations of C-reactive protein and secretory phospholipase A2 both increased (P < 0.05). Plasma levels of the leucocyte activation marker elastase-alpha1-antitrypsin complexes increased after IFN-gamma administration (P < 0.05), IFN-gamma increased the percentage of high-affinity Fcgamma-receptor (FcgammaRI) -positive neutrophils (P < 0.05), but did not affect the mean fluorescence intensity of FcgammaRI on neutrophils. Procoagulant and profibrinolytic effects of IFN-gamma were evidenced by increased plasma levels of prothrombin fragment F1 + F2, tissue-plasminogen activator and plasmin-alpha2-antiplasmin complexes (P < 0.05). CONCLUSION: We conclude that IFN-gamma selectively affects host inflammatory mediators in humans.

Acute-Phase Proteins↗

Antibodies against human papillomavirus type 16 and 18 E6 and E7 proteins in cervicovaginal washings and serum of patients with cervical neoplasia.

Serum antibodies against the E6 and E7 proteins of human papillomavirus (HPV) 16 and 18 are associated with cervical cancer. The aim of this study was to investigate the presence of local antibodies against HPV in cervicovaginal washings (CWs). In this study antibodies against the native HPV16 and HPV18 E6/E7 proteins were detectable in CWs (48%) and sera (29%) from patients with cervical cancer (n = 21) utilizing a sandwich protein enzyme-linked immunosorbent assay (ELISA). In paired CWs and sera from patients with cervical intraepithelial neoplasia (n = 38) and from healthy women (n = 22) no antibodies against these proteins were found. In 10 of 11 patients, the antibody response corresponded with the HPV type in the cervical smear and/or tumor tissue, which indicates the HPV type specificity of the assay. In 7 of 11 patients with antibody reactivity against HPV16 or HPV18 E6 and/or E7 proteins a higher level of antibody reactivity in the CWs than in the paired serum samples was found at similar inputs of total IgG. This suggests that the antibodies in the CWs against the investigated HPV proteins in these patients were locally produced.

Antibodies, Viral↗

Methodological aspects in the analysis of spontaneously produced sputum.

Analysis of sputum as a specimen containing inflammatory indices has gained considerable interest during the last decade with focus on chronic bronchitis (CB) with or without airway obstruction, cystic fibrosis (CF), chronic obstructive pulmonary disease (COPD) and asthma. The nature of the specimens requires expert skill for handling them and for performing analyses. The analysis of spontaneously produced sputum has been performed less frequently than that of induced sputum. This is surprising as several studies have shown that the collection procedures and the assay methods are highly reproducible. There are several valid parameters of sputum analysis that can be applied in research on airway inflammation and in monitoring therapy of patients. Spontaneously produced sputum can be obtained in a simple and non-invasive way, which warrants further efforts to expand the range of applications of its analysis. Here, we will critically review the procedures for collecting spontaneously produced sputum, for handling the samples, and the requirements for assay of sputum components. This will imply the reproducibility of the analysis, the recovery of solutes, the validity of assays in terms of reproducibility and of linearity of the response, the validity of the assays with respect to association with other inflammatory parameters and with clinical parameters, and the usefulness of assays with respect to their response upon treatment of patients.

Biomarkers↗

Simple dipstick assay for semi-quantitative detection of neopterin in sera.

Neopterin, a low-molecular-mass pteridine produced by macrophages, is closely associated with activation of the cellular immune system. Neopterin biosynthesis during inflammatory disease is primarily derived from interferon-activated monocytes/macrophages and neopterin concentrations may be significantly increased in a particular disease state compared to controls. A follow-up of serum neopterin concentrations during the course of an infectious disease could be useful for measuring the activity of the disease and the influence of treatment. We have developed a simple dipstick assay for the semi-quantitative detection of the neopterin concentration in the serum of patients during the course of an infectious disease. Assay performance was comparable to an ELISA, but there is no requirement for specialised equipment.

Biological Assay↗

IL-6 protein production by airway epithelial(-like) cells disabled in IL-6 mRNA degradation.

IL-6 mRNA and protein expression in human airway epithelial-like H292 cells depends on rapid, but regulable IL-6 mRNA degradation. We restricted IL-6 mRNA degradation by partially inhibiting protein synthesis and studied the IL-6 response. Despite partial inhibition of protein synthesis, IL-6 protein production was increased and prolonged. Furthermore, the threshold concentration for stimuli of IL-6 protein production decreased and the dose-response curves became steeper. Similar findings were obtained with primary human bronchial epithelial cells. This exaggerated production may apply to other proteins encoded by labile mRNA and is likely to occur during viral infection of airway epithelial cells.

Cells, Cultured↗

Double staining of intracellular cytokine proteins and T-lymphocyte subsets. Evaluation of the method in blood and bronchoalveolar lavage fluid.

An immunocytochemical staining method has been developed for simultaneous staining of both cell surface markers (CD4 and CD8) and intracellular cytokine proteins IFN-gamma, IL-4 and IL-5. Cell surface molecules were visualized with alkaline phosphatase, which was developed by Fast Blue BB. Intracellular cytokine proteins were detected by amino-ethyl carbazole. We applied this technique to T cells from T-cell lines and T-cell clones, peripheral blood mononuclear cells and broncho-alveolar lavage fluid cells. Cells were used either unstimulated or stimulated for 4 h with 1 ng/ml PMA and 1 microg/ml ionomycin, which proved to be an optimal stimulus taking cytokine staining, cell recovery and cell viability into account. We studied peripheral blood mononuclear cells from healthy subjects and found that without in vitro stimulation on average 0.4% of the cells were IFN-gamma positive cells. In unstimulated broncho-alveolar lavage fluid cells of the 2 allergic asthmatic subjects studied so far we found higher numbers of cytokine-positive cells (up to 22% of the lymphocytes being IL-4+ cells). By in vitro stimulation, the numbers of cytokine-positive peripheral blood mononuclear cells from the healthy subjects were increased to maximally 5% IFN-gamma+ cells. In stimulated lavage fluid cells from allergic asthmatic subjects maximally 34% of the lymphocytes became IFN-gamma+. We conclude that this method allows detection of intracellular cytokine proteins in both CD4+ and CD8+ T cells without the need for stimulating the cells in vitro. In vitro stimulation may change the cytokine profile detected.

Adult↗

Lung epithelial H292 cells induce differentiation of immature human HMC-1 mast cells by interleukin-6 and stem cell factor.

BACKGROUND: Immature mast cells migrate into tissues where they differentiate into mature mast cells under the influence of local factors. In the airways of asthmatics increased numbers of chronically activated mast cells are located nearby the airway epithelium. OBJECTIVE: The aim of this study was to evaluate whether and, if so, which products released by epithelial cells may affect mast cell proliferation and differentiation. METHODS: We performed in vitro studies using the human lung mucoepidermoid carcinoma-derived H292 cell line and the immature human mast cell line, HMC-1. Proliferation was assessed by 3H-thymidine incorporation. Differentiation of HMC-1 cells was inferred from tryptase production. RESULTS: Exposure of HMC-1 cells to medium conditioned for 48 h by H292 cells resulted in a reduction of proliferation with 65 +/- 4.9% (mean +/- SEM, n = 9) at day 5. Culturing HMC-1 cells for 8 days in the presence of H292-conditioned medium resulted in morphological changes indicative of differentiation, and in a 3.0 +/- 0.4-fold increase of tryptase production (P = 0.0039, n = 9). Conditioned medium from H292 cells that were stimulated by LPS also inhibited HMC-1 proliferation. Inhibitory antibodies against two mediators from H292 cells, interleukin-6 (IL-6) and stem cell factor (SCF), abolished the increase in HMC-1 tryptase production induced by H292-conditioned medium. Recombinant human (rh) IL-6, but not rhSCF, reduced HMC-1 proliferation with 44% and 13% at day 3 and 5, respectively. Surprisingly, rhIL-6 did not increase HMC-1 tryptase production significantly whereas incubation with rhSCF did (1.5 +/- 0.1-fold, P = 0.002, n = 10) although the increase was less than observed for conditioned medium. CONCLUSION: Epithelial-derived IL-6 and SCF are implicated in differentiation of HMC-1 cells but additional factors are not excluded. As activated primary bronchial epithelial cells also express IL-6 and SCF, it should be considered that these cells are involved in mast cell differentiation within the airways, particularly in diseases where epithelial cells are activated, such as asthma.

Antibodies↗

The role of Fcgamma receptor polymorphisms and C3 in the immune defence against Neisseria meningitidis in complement-deficient individuals.

Individuals with either a late (C5-9) complement component deficiency (LCCD) or properdin deficiency are at increased risk to develop meningococcal disease, often due to serogroups W135 and Y. Anti-meningococcal defence in both LCCD persons and properdin-deficient individuals without bactericidal antibodies depends mainly on phagocytosis. Three types of opsonin receptors are involved in phagocytosis by polymorphonuclear cells (PMN). These represent the polymorphic FcgammaRIIa (CD32) and FcgammaRIIIb (CD16b) receptors, and the C3 receptor CR3 (CD11b/CD18). When the distribution of FcgammaRIIa and FcgammaRIIIb allotypes was assessed in 15 LCCD and in 15 properdin-deficient patients with/without previous meningococcal disease, we found the combination of FcgammaRIIa-R/R131 with FcgammaRIIIb-NA2/NA2 allotypes to be associated with previous meningococcal disease (odds ratio 13.9, Fisher's test P = 0.036). No such relation was observed in the properdin-deficient patients. The importance of FcgammaRIIa allotypes was also demonstrated using in vitro phagocytosis assays. PMN from FcgammaRIIa-R/R131 homozygous donors internalized IgG2 opsonized meningococci W135 significantly (P < 0.05) less than PMN from FcgammaRIIa-H/H131 donors. When properdin-deficient serum was tested, it was observed that reconstitution with properdin resulted in enhanced PMN phagocytosis of the W135 meningococci (P = 0.001). This enhanced phagocytosis was parallelled by an increase in C3 deposition onto the opsonized meningococci W135 (r = 0.6568, P = 0. 01). We conclude that the occurrence of meningococcal disease in LCCD patients is associated with certain FcgammaR allotypes. Properdin-deficient individuals are susceptible to meningococcal disease because of an insufficient C3 deposition on the surface of meningococci, resulting in insufficient phagocytosis.

Adolescent↗

Immunoglobulins in chronic renal failure of childhood: effects of dialysis modalities.

BACKGROUND: It is not clear whether low serum levels of IgG (subclasses), previously demonstrated in children on peritoneal dialysis (PD), are related to the PD procedure or to factors associated with chronic renal failure (CRF). The aim of our study was to analyze the effect of PD on serum and PD effluent (PDE) IgG and subclass levels in children with end-stage renal failure. METHODS: We measured albumin, IgG, IgA, IgM, and IgG subclasses in serum and PDE from children on PD (N = 40) and compared the serum values with those of children treated with hemodialysis (HD, N = 23) or presenting with CRF but not yet dialyzed (CRF; N = 63), and with a group of healthy controls (HCs; N = 67). Sixteen PD children could be followed sequentially from before starting PD and eight during a peritonitis episode. RESULTS: Forty percent of the PD children showed reduced serum IgG2 levels (P = 0.0003) compared with 35% in HD (P = 0.006), 33% in CRF (P = 0.001), and 9% in HC children. IgG1 deficiencies were observed in 25% of PD patients (P < 0.0001), 4% of HD (P = NS), 16% of CRF (P = 0.0005), and 0% of HC children. IgG3 and IgG4 deficiencies were observed less frequently. Peritoneal clearances were similar for total IgG, IgG1, IgG2, and IgG4, but were lower for IgG3 (P < 0.05). No relationships were found between clearances and age or duration of PD treatment. Total IgG (P = 0. 003) and IgG1 (P = 0.002) levels declined just after starting PD. Peritonitis was associated with temporarily increased peritoneal loss of Ig, while the serum concentrations were unaffected. No significant relationship was found between the peritonitis incidence and reduced IgG or subclasses. However, all children with two or more peritonitis episodes per year had a reduced Ig level. CONCLUSIONS: Although the mean serum concentrations of immunoglobulins were normal in all studied groups, a deficiency of one or more IgG subclasses was present in all groups with renal failure, suggesting inhibition of their synthesis by the uremic state. Ig deficiencies were more frequently found in PD, likely caused by protein loss in PDE. A high peritonitis incidence was associated with reduced serum Ig levels.

Acute Disease↗

Induced sputum and bronchoalveolar lavage as tools for evaluating the effects of inhaled corticosteroids in patients with asthma.

Changes in airway inflammation can be studied with bronchoalveolar lavage, but the widespread use of this procedure is limited by its invasiveness. The aim of this study was to evaluate the usefulness of induced sputum as a non-invasive alternative to bronchoalveolar lavage for studying changes in airway inflammation in patients with asthma. Thirty patients were treated for 12 weeks with an inhaled corticosteroid (fluticasone propionate (FP), 250 microg twice daily) or a short-acting beta-agonist (salbutamol (Sb), 400 microg twice daily) in a double-blind, double-dummy, randomized parallel group study. Sputum induction with hypertonic saline solution was performed twice before treatment and after 4, 8, 10, and 11 weeks of treatment. Bronchoalveolar lavage fluid divided into two pools (first 60 mL portion as bronchoalveolar lavage/bronchial wash (BAL/BW) and subsequent 80 mL as bronchoalveoalar lavage (BAL)) was obtained before and after 12 weeks of treatment. Changes in cell differentials and plasma-protein leakage (alpha2-macroglobulin, albumin, and their ratio (relative coefficient of excretion, RCE)) were analyzed in induced sputum and were compared with changes in BAL/BW and BAL. During treatment with FP, the PC20histamine (interpolated concentration of histamine that caused a fall in FEV1 of 20% of the baseline value) increased (P < .0001), and the percentage of eosinophils (P = .004), levels of (alpha2-macroglobulin (P = .09) and RCE (P = .007) decreased in sputum. These changes were different from those in the Sb group (PC20histamine P< .0001, eosinophils P= .004, alpha2-macroglobulin P= .003, RCE P = .01), in which alpha2-macroglobulin showed a significant increase (P = .015). Changes in the percentage of eosinophils and in the levels of alpha2-macroglobulin in sputum were associated with changes in the PC20histamine (Rs = -0.59, P = .007 and Rs = -0.47, P = .03, respectively). These correlations did not reach significance in BAL/BW and BAL fluid. The statistical power to detect changes in induced sputum was higher for the percentage of eosinophils and similar for plasma protein leakage as compared with analysis of BAL/BW and BAL fluid. We conclude that the analysis of induced sputum is a useful, non-invasive alternative to bronchoalveolar lavage for assessing the effects of antiinflammatory drugs in asthma.

Administration, Inhalation↗

Airway inflammation in nonobstructive and obstructive chronic bronchitis with chronic haemophilus influenzae airway infection. Comparison with noninfected patients with chronic obstructive pulmonary disease.

Nonencapsulated Haemophilus influenzae often causes chronic infections of the lower respiratory tract in both nonobstructive and obstructive chronic bronchitis. We assessed airway inflammation in clinically stable, chronically H. influenzae-infected patients with nonobstructive (CB-HI, n = 10) and in patients with obstructive chronic bronchitis (COPD-HI, n = 10) by analyses of the sol phase of spontaneously expectorated sputum (SSP). As compared with the CB-HI group, the COPD-HI group had significantly higher (p < 0.05) levels of myeloperoxidase (MPO) and tumor necrosis factor (TNF)-alpha in their SSP, whereas the degree of plasma protein leakage (SSP-to-serum ratio of plasma proteins) and the levels of interleukin (IL)-8, secretory IgA, and lactoferrin were similar in the two groups. These findings point to differences in pathophysiology in CB-HI and COPD-HI. The high level of TNF-alpha in the SSP of COPD-HI patients is in accord with the proposed role of TNF-alpha in the development of airway obstruction in COPD patients. In apparent contradiction, low levels of TNF-alpha were found in the SSP of noninfected but otherwise similar COPD patients (n = 9). This finding, however, does not exclude an exaggerated TNF-alpha response to infection or another stimulus in the airways of COPD patients. The SSP levels of MPO and IL-8, and the degree of plasma protein leakage in the COPD-HI group, were retrospectively compared with and found significantly higher than those of noninfected COPD patients, suggesting a more marked inflammatory response in COPD-HI. Whether this reflects a direct cause-and-effect relationship should be addressed in a future long-term prospective study involving repeated measurements in the same patients.

Bronchitis↗

[Immunology in medical practice. XXI. Laboratory tests for immunologic diseases].

Clinical immunology has gained its firm place in health care. There are now established laboratory tests giving insight into the functioning of the immune system in the normal and diseased individual. The laboratory diagnostic tests are related to immune deficiencies, infectious diseases, allergic diseases, autoimmune diseases (both generalized and organ-specific ones), the HLA system and malignancies of immune cells. In this review the application of a number of laboratory tests in the diagnosis of immunological diseases is discussed. In the Netherlands a laboratory specialist, the 'medical immunologist' deals with the development, implementation and performance of the immunological diagnostic tests in health care.

Allergy and Immunology↗

Increased IL-6 and IL-8 levels in cervicovaginal secretions of patients with cervical cancer.

OBJECTIVE: Conflicting data exist on IL-6 production by human papillomavirus (HPV) immortalized cell lines and several cervical carcinoma cell lines. However, no information has been reported on the levels of cytokines in cervicovaginal washings in relation to cervical neoplasia. The aim of this study was to investigate whether local production of IL-6 could be found and whether the level of this cytokine was related to the severity of cervical neoplasia. IL-8 was measured to obtain additional information on an inflammatory cytokine with possible epithelial origin. METHODS: Cervicovaginal washings and sera were obtained from 35 patients with invasive cervical cancer, 62 patients with cervical intraepithelial neoplasia (CIN), and 25 control subjects. IL-6 and IL-8 levels were determined by ELISA. HPV DNA in cervical smears was detected by a HPV-16-specific PCR method and additionally by CPI/IIG PCR. Histological analysis of the inflammatory infiltrate was performed on hematoxylin-eosin-stained tissue sections. RESULTS: In the patients with cervical cancer, those with CIN, and the controls, the median IL-6 concentration in cervicovaginal washings was 171 pg/ml (interquartile range: 54-780), 22 pg/ml (<2-73), and < 2 pg/ml (<2-<2), respectively. For IL-8, the levels were 2756 pg/ml (1651-7107), 489 pg/ml (248-1158), and 631 pg/ml (346-897), respectively. In most subjects the local levels were much higher than in serum. Local IL-6 and IL-8 levels were significantly higher in patients with cervical carcinoma compared with CIN patients and controls. Likewise, local IL-6 levels were increased in patients with CIN compared with controls. No relation was found between cytokine levels and CIN grade or between cytokine levels and the inflammatory infiltrate scored by histological analysis. CONCLUSIONS: There is local production of IL-6 and IL-8 in cervicovaginal secretions, and the production of IL-6 was related to the severity of cervical neoplasia.

Adult↗