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Lars Olaf Cardell

Publications and source records attributed to Lars Olaf Cardell.

14 recordsLinked to original sources

A network-based analysis of the late-phase reaction of the skin.

BACKGROUND: The late-phase reaction (LPR) of the skin is an in vivo model of allergic inflammation. OBJECTIVE: We sought to identify disease-associated pathways in the LPR using a network-based analysis. METHODS: The LPR was examined by means of DNA microarray analysis of skin biopsy specimens from 10 patients with allergic rhinitis and 10 healthy control subjects. The results were further analyzed in 2 different materials consisting of nasal fluids and allergen-challenged CD4(+) T cells from patients with allergic rhinitis. RESULTS: The DNA microarray analysis revealed several genes of known relevance to allergy. The eosinophil marker Charcot-Leyden crystal protein (CLC) that encodes Charcot-Leyden crystal protein differed most in expression. A network-based analysis showed upregulation of IL-4- and CCL4-dependent pathways and downregulation of a TGF-beta-induced pathway. CCL4 is expressed by CD4(+) T cells and chemotactic for eosinophils. We hypothesized that allergen induces release of CCL4 from T(H)2 cells and that this contributes to influx of eosinophils. Further analysis showed increase of CCL4 protein in nasal fluids from allergic patients during the season. Allergen challenge of PBMCs resulted in proliferation of T(H)2 cells and increased production of CCL4 in CD4(+) T cells from allergic patients. An analysis of the DNA microarray data revealed a significant correlation between CCL4 and the eosinophil marker CLC. CONCLUSION: A network-based analysis of the LPR showed increased activity of IL-4- and CCL4- dependent pathways and downregulation of the TGF-beta-induced pathway. Allergen-induced release of CCL4 from T(H)2 cells might contribute to influx of eosinophils during the LPR. CLINICAL IMPLICATIONS: Involvement of multiple interacting pathways indicates that it might be difficult to identify one single mediator as a biomarker or drug target in allergic inflammation.

Adult↗

Toll-like receptors in cellular subsets of human tonsil T cells: altered expression during recurrent tonsillitis.

BACKGROUND: The palatine tonsils have a pivotal role in immunological detection of airborne and ingested antigens like bacteria and viruses. They have recently been demonstrated to express Toll-like receptors (TLRs), known to recognize molecular structures on such microbes and activate innate immune responses. Their activation might also provide a link between innate and adaptive immunity. In the present study, the expression profile of TLR1-TLR10 was characterized in human tonsil T cells, focusing on differences between subsets of CD4+ T helper (Th) cells and CD8+ cytotoxic T lymphocytes (CTL). The study was also designed to compare the TLR expression in T cells from patients with recurrent tonsillitis and tonsillar hyperplasia. METHODS: Tonsils were obtained from children undergoing tonsillectomy, and classified according to the clinical diagnoses and the outcome of tonsillar core culture tests. Two groups were defined; recurrently infected tonsils and hyperplastic tonsils that served as controls. Subsets of T cells were isolated using magnetic beads. The expression of TLR transcripts in purified cells was assessed using quantitative real-time RT-PCR. The corresponding protein expression was investigated using flow cytometry and immunohistochemistry. RESULTS: T cells expressed a broad repertoire of TLRs, in which TLR1, TLR2, TLR5, TLR9 and TLR10 predominated. Also, a differential expression of TLRs in CD4+ and CD8+ T cells was obtained. TLR1 and TLR9 mRNA was expressed to a greater extent in CD4+ cells, whereas expression of TLR3 mRNA and protein and TLR4 protein was higher in CD8+ cells. CD8+ cells from infected tonsils expressed higher levels of TLR2, TLR3 and TLR5 compared to control. In contrast, CD4+ cells exhibited a down-regulated TLR9 as a consequence of infection. CONCLUSION: The present study demonstrates the presence of a broad repertoire of TLRs in T cells, a differential expression in CD4+ and CD8+ cells, along with infection-dependent alterations in TLR expression. Collectively, these results support the idea that TLRs are of importance to adaptive immune cells. It might be that TLRs have a direct role in adaptive immune reactions against infections. Thus, further functional studies of the relevance of TLR stimulation on T cells will be of importance.

Bacterial Infections↗

Altered levels of the soluble IL-1, IL-4 and TNF receptors, as well as the IL-1 receptor antagonist, in intermittent allergic rhinitis.

BACKGROUND: The effects of cytokines are modulated by soluble cytokine receptors (SCR) and receptor antagonists. Therefore, allergic disease may depend on altered proportions between cytokines, their SCR and receptor antagonists, rather than absolute changes in cytokine levels. Little is known about SCR in intermittent allergic rhinitis (IAR). OBJECTIVE: To examine the concentrations of SCR, i.e. sIL-1R2, sIL-4R, sIL-6R and sTNFR1, as well as the interleukin-1 receptor antagonist (IL-1Ra) in nasal fluids from allergen-challenged patients with IAR and healthy controls. METHODS: 30 patients with birch- or grass-pollen-induced IAR and 30 healthy controls were studied. In the patients nasal fluids were obtained before as well as 1 and 6 h after allergen provocation. RESULTS: Both symptom scores and rhinoscopic signs of rhinitis increased in the patients after allergen challenge. Comparisons between patients and controls showed that sIL-4R was lower in patients before and 1 and 6 h after provocation. IL-1Ra was lower before and 1 h after provocation. In addition, lower concentrations of sTNFR1 were found in patients after 1 h, while sIL-1R2 concentrations were higher after 1 h. Comparisons of patients before and after challenge showed that IL-1Ra and sTNFR1 decreased after 1 h, while sIL-1R2 increased. No significant differences were found compared to 6 h. sIL-6R did not significantly differ between the study groups. CONCLUSIONS: After allergen challenge, significant changes in the nasal fluid levels of IL-1Ra, sIL-1R2 and sTNFR1 were found. By contrast, sIL-4R remained at lower levels than in controls both before and after challenge. Since sIL-4R modulates IgE synthesis, this may play a role in the pathogenesis of IAR.

Adolescent↗

Gene profiling reveals increased expression of uteroglobin and other anti-inflammatory genes in glucocorticoid-treated nasal polyps.

BACKGROUND: Treatment with local glucocorticoids (GCs) decreases symptoms and the size of nasal polyps. This might depend on the downregulation of proinflammatory genes, as well as the upregulation of anti-inflammatory genes. OBJECTIVE: We sought to identify GC-regulated anti-inflammatory genes in nasal polyps. METHODS: Affymetrix DNA microarrays were used to analyze the expression of 22,283 genes in 4 nasal polyps before and after local treatment with fluticasone (400 microg/d). Expression of uteroglobin and mammaglobin B was analyzed with real-time PCR in 6 nasal polyps and in nasal biopsy specimens from 6 healthy control subjects. RESULTS: Two hundred three genes had changed in expression in treated polyps, and 139 had known functions: 54 genes were downregulated, and 85 were upregulated. Genes associated with inflammation constituted the largest single functional group. These genes affected key steps in inflammation (eg, immunoglobulin production; antigen processing and presentation; and the chemoattraction and activation of granulocytes, T cells, and B cells). Several proinflammatory genes were downregulated. In contrast, some anti-inflammatory genes were upregulated. The gene that increased most in terms of expression was uteroglobin. This was confirmed with real-time PCR. By contrast, expression of uteroglobin was lower in untreated polyps than in healthy nasal mucosa. Immunohistochemical investigation showed staining of uteroglobin in the epithelium and in seromucous glands in control subjects and in nasal polyps. CONCLUSION: Upregulation of anti-inflammatory genes, such as uteroglobin, might contribute to the effects of local treatment with GCs in nasal polyps.

Adult↗

DNA microarray analysis of chromosomal susceptibility regions to identify candidate genes for allergic disease: a pilot study.

OBJECTIVE: To examine whether DNA microarray analysis of chromosomal susceptibility regions for allergy can help to identify candidate genes. MATERIAL AND METHODS: Nasal biopsies were obtained from 23 patients with allergic rhinitis and 12 healthy controls. RNA was extracted from the biopsies and pooled into three patient and three control pools. These were then analysed in duplicate with DNA microarrays containing 12626 genes. Candidate genes were further examined in nasal biopsies (real-time polymerase chain reaction) and blood samples (single nucleotide polymorphisms) from other patients with allergic rhinitis and from controls. RESULTS: A total of 37 differentially expressed genes were identified according to criteria involving both the size and consistency of the gene expression levels. The chromosomal location of these genes was compared with the chromosomal susceptibility regions for allergic disease. Using a statistical method, five genes were identified in these regions, including serine protease inhibitor, Kazal type, 5 (SPINK5) and HLA-DRB2. The relevance of these genes was examined in other patients with allergic rhinitis and in controls; none of the genes were differentially expressed in nasal biopsies. Moreover, no association between allergic rhinitis and SPINK5 polymorphisms was found, at either the genotype or haplotype level. CONCLUSIONS: DNA microarray analysis of chromosomal susceptibility regions did not lead to identification of candidate genes that could be validated in a new material. However, because gene polymorphisms may cause differential gene expression, further studies, including validation data, are needed to examine this approach.

Adolescent↗

Increased expression of Vascular Endothelial Growth Factor-A in seasonal allergic rhinitis.

Increased vascular dilatation and permeability characterize allergic rhinitis. In this study oligonucleotide microarrays (Affymetrix HuGe95A) were used to identify differentially expressed vasoactive genes in nasal biopsies from 23 patients with symptomatic seasonal allergic rhinitis (SAR) and 12 healthy controls. RNA was extracted from the biopsies and pooled in three patient and three control pools. Out of 12,626 analysed transcripts, 39 were higher and 81 lower in the patients. Of these transcripts two have vasoactive effects: Vascular Endothelial Growth Factor-A (VEGF-A) and the Beta-1-Adrenergic Receptor. Both were higher in patients than in controls. The mean +/- SEM expression levels in arbitrary units of VEGF-A were 130 +/- 123 in the patients and 59 +/- 53 in the controls. The fold ratio in expression levels between patients/controls was 2.2. The corresponding values for the beta-1-adrenergic receptor were 129 +/- 123 in the patients and 40 +/- 31 in the controls. The fold ratio between patient/controls was 3.2. The role of VEGF-A was assessed by determining VEGF-A concentrations in nasal fluids from another 30 patients with SAR before and after allergen provocation. VEGF-A increased from 124.3 +/- 30.2 to 163.2 +/- 37.8 pg/ml after challenge, P < 0.05. In summary, oligonucleotide microarray analysis of nasal biopsies and protein analyses of nasal fluids indicate that VEGF-A may be an important mediator in SAR.

Betula↗

PACAP enhances the expression of CD11b, CD66b and CD63 in human neutrophils.

Pituitary adenylate cyclase-activating peptide (PACAP) is a neuropeptide with strong bronchodilator capacity, present in the human airways. There is recent evidence that PACAP decreases the release of proinflammatory cytokines. We have previously shown that PACAP inhibits neutrophil chemotaxis, but altogether little is known about the effects of PACAP on granulocytes. The present study was designed to investigate if PACAP and the closely related peptide vasoactive intestinal peptide (VIP) could affect the cell surface expression of CD11b, CD63 and CD66b in human neutrophils. Neutrophils isolated from 12 healthy blood donors were incubated with either PACAP or VIP, and the expression of neutrophil cell surface markers was assessed using flowcytometry. Neutrophils incubated with PACAP38 exhibited a marked, concentration-dependent increase in their expression of CD11b, CD63 and CD66b. In contrast, neutrophils incubated with VIP showed no increase of the investigated surface markers. This indicates a role for PACAP in granulocyte activation, mediated via a pathway not shared with VIP. Together with the previously presented data on leukocyte migration it suggests that PACAP acts as a regulator of neutrophil inflammation.

Antigens, CD↗

Increased carbon monoxide levels in the nasal airways of subjects with a history of seasonal allergic rhinitis and in patients with upper respiratory tract infection.

BACKGROUND: Carbon monoxide (CO) has emerged as an endogenously produced gaseous mediator known to be involved in bronchial smooth muscle regulation. Increased amounts of CO have been found in exhaled air during asthma and lower airway inflammation. Recently CO has been shown to be produced in the nasal airways, but there are no reports of altered CO levels in nasal airways during inflammation. OBJECTIVE: This study was designed to investigate if CO levels increase in the human nasal airways during inflammatory conditions, such as allergy and upper airway respiratory tract infection (URTI). METHODS: CO was sampled separately from the upper and lower airways of 13 healthy control subjects, six patients with a history of allergic rhinitis and six patients with URTI. RESULTS: Nasal CO levels were increased in subjects with allergic rhinitis, compared to healthy controls (2.07 +/- 0.15 ppm, n = 6 and 1.62 +/- 0.08 ppm, n = 13, respectively, P < 0.01). CO levels were also increased in patients with URTI, compared to the same controls (1.92 +/- 0.09 ppm, n = 6, P < 0.05). Normal levels of CO were found in air from the lower airways among subjects with allergic rhinitis, whereas corresponding levels in the URTI patients were increased. CONCLUSION: The present data demonstrates that upper airway CO levels increase in parallel with different inflammatory stimuli, such as allergy and infection, suggesting a role for CO as marker or mediator of nasal inflammation.

Adult↗

Epithelial cells in nasal fluids from patients with allergic rhinitis: how do they relate to epidermal growth factor, eosinophils and eosinophil cationic protein?

The nasal epithelium protects the underlying tissue from damage. Epithelial cell growth is controlled by epidermal growth factor (EGF) and is possibly affected by toxic proteins, e.g. eosinophil cationic protein (ECP). The aims of this study were to examine nasal fluid epithelial cell counts and their relations to EGF, eosinophils and ECP in 23 patients with seasonal allergic rhinitis and 20 healthy controls. Nasal fluid epithelial cell counts were lower in patients than in controls. EGF levels did not differ between patients and controls, and correlated with epithelial cell counts in controls but not in patients. Eosinophils and ECP were higher in patients than in controls, but did not correlate with epithelial cell counts. The role of growth factors, such as EGF, in regulating epithelial cells merits further study.

Adolescent↗

A decrease in maxillary sinus pressure, as seen in upper airway allergy or infection, results in an increase in upper airway nitric oxide levels.

The paranasal sinuses are connected to the nasal cavity via small osties. Ostial occlusion, caused by mucosal swelling, will result in a slowly increasing negative pressure inside the sinus cavity. In parallel, the oxygen content in the sinus will decrease, resulting in the development of relative hypoxia. Hypoxia is a powerful inducer of nitric oxide (NO) synthase, and inducible NO synthase has been shown to be present in considerable amounts in the upper airways, including the sinuses. The present study was designed to investigate whether a reduction in sinus pressure would affect upper airway NO production. Thirteen healthy volunteers were investigated. A pressure chamber was used to lower the ambient pressure to -4.9 kPa. NO was sampled from one nostril or via a drainage tube inserted into the maxillary sinus before, during and after the hypobaric exposure. When the pressure was decreased, NO levels increased from 256 +/- 15 to 316 +/- 19 ppb (n = 13, p < 0.001). The NO levels remained elevated (282 +/- 21 ppb; p < 0.05) when measurements were repeated 20 min after leaving the chamber. The nasal airway resistance (V2tot) also increased as a result of the chamber session (from 16 +/- 2 degrees before to 21 +/- 3 degrees after; p < 0.05). An increase in NO levels was also found when the experiments were repeated with NO sampled directly from the maxillary sinus (225 +/- 6 before and 265 +/- 9 ppb after; n = 6, p < 0.001). For control purposes the nasal analyses were repeated again, this time under hyperbaric conditions (+ 4.9 kPa). This resulted in a slight decrease in the NO levels (from 273 +/- 22 to 241 +/- 17 ppb; n = 10, p < 0.001), but there was no change in the nasal airway resistance. We conclude that a reduction in sinus pressure, as seen in upper airway allergy or infection, may result in an increase in upper airway NO production.

Adult↗

The paranasal sinuses as reservoirs for nitric oxide.

OBJECTIVE: Nitric oxide (NO) is an important mediator and inflammatory marker in human upper airways. Enzymes responsible for NO production have been demonstrated both in the nose and in the paranasal sinuses, but NO levels in the sinuses are reported to be several times higher than those in the nose. It has been postulated that the paranasal sinuses may be the primary sites for NO production in the upper respiratory tract. The present study was designed to compare the NO levels sampled from the nose with those found in the paranasal sinuses. MATERIAL AND METHODS: NO levels in the maxillary sinus and nose were determined using a continuous chemiluminescence measuring technique in seven healthy volunteers. RESULTS: When NO was sampled, via a drainage tube inserted into the maxillary sinus, a transient peak in NO level was recorded. The maximal NO level (5,761 +/- 1,513 ppb; n = 7) was reached within 10 s and was followed by the establishment of a lower steady-state level (304 +/- 51 ppb). When NO was continuously sampled from the nose a steady-state level, similar to that found in the sinus, was immediately established (313 +/- 52 ppb). CONCLUSION: The data presented confirm previous findings of extremely high NO levels in the paranasal sinuses and suggest that these cavities may also function as reservoirs for NO.

Adult↗