Lars-Olaf Cardell

Allergic rhinitis and the common cold--high cost to society.

To cite this article: Hellgren J, Cervin A, Nordling S, Bergman A, Cardell LO. Allergic rhinitis and the common cold – high cost to society. Allergy 2010; 65: 776–783.

Basophil allergen threshold sensitivity: a useful approach to anti-IgE treatment efficacy evaluation

Background:  Monitoring of the allergen sensitivity of a patient is most important for optimal patient care and a basic prerequisite for immunomodulating treatment. The objective of this study was to investigate how basophil allergen sensitivity can be applied in the monitoring of anti‐immunoglobulin E (IgE) treatment.

A distinct Toll-like receptor repertoire in human tonsillar B cells, directly activated by Pam3CSK4, R-837 and CpG-2006 stimulation

Toll‐like receptors (TLRs) recognize specific pathogen‐associated molecular patterns (PAMPs), which subsequently trigger innate immunity. Recent data also suggest a role for TLRs in the direct activation of adaptive immune cells. In the present study, the expression and function of TLR1–TLR10 were characterized in purified human tonsillar B cells, focusing on differences among CD19+ CD38– CD27– (naïve B cells), CD19+ IgD– CD27–[germinal centre (GC) B cells] and CD19+ CD38– CD27+ (memory B cells) cells. The study was also designed to compare the TLR expression in B cells obtained from infected and hyperplastic tonsils that served as controls. The results demonstrated a distinct repertoire of TLRs, in which TLR1, TLR2, TLR7, TLR9 and TLR10 predominated. No differences were found among naïve, GC and memory B cells. Tonsillar infection did not substantially alter the TLR expression profile in ex vivo‐isolated B‐cell subsets. Purified CD19+ B cells stimulated with Pam3CSK4, R‐837 and CpG oligodeoxynucleotide (ODN) 2006, via TLR1/TLR2, TLR7 and TLR9, respectively, showed an induction of interleukin‐6 secretion and an up‐regulated expression of human leucocyte antigen (HLA)‐DR. Collectively, the present study demonstrates that B cells exhibit constitutively high levels of specific TLRs, which are not developmentally regulated during the B‐cell differentiation process. Ongoing microbial infections, such as chronic tonsillitis, do not appear to affect the TLR profile in B cells. Furthermore, the distinct expression of TLRs allows B cells to respond directly to the cognate PAMPs. This further emphasizes the role of TLRs in directly activating adaptive immune cells.

Toll-like receptor stimulation induces airway hyper-responsiveness to bradykinin, an effect mediated by JNK and NF-κB signaling pathways

Airway infections induce hyper‐responsiveness in asthmatic patients. Toll‐like receptors (TLR) mediate inflammatory responses to microbes. Occurrence and effects of TLR2, TLR3 and TLR4 were examined in a mouse organ culture model of asthma focusing on the smooth muscle responses to bradykinin. TLR2, TLR3 and TLR4 mRNA, and TLR2 and TLR4 immunoreactivity were detected in the tracheal muscle layer. Tracheal organ culture for 1 or 4 days with lipopolysaccharide (LPS; TLR2/4 agonist) or polyinosinic polycytidylic acid (poly‐I‐C; TLR3 agonist) enhanced bradykinin‐ and [des‐Arg9]‐bradykinin‐induced contractions. Simultaneous LPS and poly‐I‐C treatment resulted in synergistic enhancement of bradykinin‐induced contraction. In carbachol‐pre‐contracted segments TLR stimulationinduced less potent relaxations to bradykinin and [des‐Arg9]‐bradykinin. The LPS and poly‐I‐C enhancement of bradykinin‐induced contraction was inhibited by the transcriptional inhibitor actinomycin‐D, dexamethasone, the proteasome inhibitor MG‐132 and the c‐Jun N‐terminal kinase (JNK) inhibitor SP600125. LPS and poly‐I‐C induced translocation of NF‐κB p65 to the nucleus and up‐regulation of kinin B1 and B2 receptor mRNA. In summary, TLR2, TLR3 and TLR4 are expressed in the mouse tracheal smooth muscle. Costimulation of these receptors results in NF‐κB‐ and JNK‐mediated transcription of B1 and B2 receptor, inducing hyper‐responsiveness to bradykinin.

Up-regulation of Toll-like receptors 2, 3 and 4 in allergic rhinitis

BackgroundToll-like receptors enable the host to recognize a large number of pathogen-associated molecular patterns such as bacterial lipopolysaccharide, viral RNA, CpG-containing DNA and flagellin. Toll-like receptors have also been shown to play a pivotal role in both innate and adaptive immune responses. The role of Toll-like receptors as a primary part of our microbe defense system has been shown in several studies, but their possible function as mediators in allergy and asthma remains to be established. The present study was designed to examine the expression of Toll-like receptors 2, 3 and 4 in the nasal mucosa of patients with intermittent allergic rhinitis, focusing on changes induced by exposure to pollen.Methods27 healthy controls and 42 patients with seasonal allergic rhinitis volunteered for the study. Nasal biopsies were obtained before and during pollen season as well as before and after allergen challenge. The seasonal material was used for mRNA quantification of Toll-like receptors 2, 3 and 4 with real-time polymerase chain reaction, whereas specimens achieved in conjunction with allergen challenge were used for immunohistochemical localization and quantification of corresponding proteins.ResultsmRNA and protein representing Toll-like receptors 2, 3 and 4 could be demonstrated in all specimens. An increase in protein expression for all three receptors could be seen following allergen challenge, whereas a significant increase of mRNA only could be obtained for Toll-like receptor 3 during pollen season.ConclusionThe up-regulation of Toll-like receptors 2, 3 and 4 in the nasal mucosa of patients with symptomatic allergic rhinitis supports the idea of a role for Toll-like receptors in allergic airway inflammation.

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

BackgroundThe 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.MethodsTonsils 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.ResultsT 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.ConclusionThe 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.

An assay to evaluate the long-term effects of inflammatory mediators on murine airway smooth muscle: evidence that TNFalpha up-regulates 5-HT(2A)-mediated contraction.

Asthma research is arguably limited by an absence of appropriate animal models to study the pharmacology of inflammatory mediators that affect airway hyperresponsiveness and remodelling. Here we assessed an assay based on mouse tracheal segments cultured for 1–32 days, and investigated contractile responses mediated by muscarinic and 5‐hydroxytryptamine (5‐HT) receptors following long‐term exposure to tumour necrosis factor‐alpha (TNFα). Following culture, in the absence of TNFα, maximum contractile responses to KCl and carbachol were similar, with an increase in response up to day two and a decrease to a stable level after 8 days. Maximal relaxations to isoprenaline were not affected by the culture procedure. The potency of KCl and isoprenaline increased throughout the study. DNA microarray data revealed that global gene expression changes were greater when tissues were introduced to culture than when they were maintained in culture. The morphology of smooth muscle cells was maintained throughout the culture period. 5‐HT induced a weak contraction in both fresh and cultured (up to 8 days) segments. Culture with TNFα produced a time‐ and concentration‐dependent increase in the maximal contraction to 5‐HT, evidently mediated by 5‐HT2A receptors, whereas, the potency for carbachol was reduced. In conclusion, the phenotype of airway smooth muscle remained largely intact during the culture period, even though minor changes were obtained during the first days of culture. The time‐dependent effect of TNFα indicates the importance of studying the long‐term effect of cytokines on the smooth muscle cells in relation to airway hyperresponsiveness and remodelling.

The size of the disease relevant IgE antibody fraction in relation to total-IgE predicts the efficacy of anti-IgE (Xolair ) treatment

Background:  Some patients with allergic asthma treated with anti‐IgE (Xolair®) do not become symptom free. Better criteria for response assessment than allergy skin tests or IgE determination are needed. The impact of the size of the disease relevant allergen‐specific IgE antibody fraction, i.e. the percentage of IgE antibody of total IgE, was evaluated in cat allergic patients treated with the recommended doses of Xolair®. Results were measured as changes in basophil allergen threshold sensitivity (CD‐sens).

Regional variation in appearance of vascular contractile endothelin-B receptors following organ culture.

OBJECTIVE The aim of this study was to investigate the appearance of contractile endothelin (ET)-B receptors following organ culture in different vascular regions. METHOD The contractile responses of vascular smooth muscle induced by ET-1 and the selective ETB receptor agonist sarafotoxin 6c (S6c) were investigated in circular segments representing eight vascular regions in the rat (aorta, femoral artery, mesenteric artery, branch of the mesenteric artery, proximal and distal parts of the caudal artery, femoral and mesenteric veins). To allow the ETB receptor to be expressed, the segments were placed in organ culture for 1 to 5 days. Pharmacological characterisation of the ET receptors was performed in mesenteric arterial segments. All contractile responses were measured in percentage of K(+)-induced contraction. RESULTS ET-1 induced strong concentration-dependent contractions of all fresh (not cultured) segments. S6c had negligible effects on all fresh vessels with the exception of the mesenteric vein, where a small contraction was seen. After 1 day of organ culture all tested segments, with the exception of aorta and the proximal part of the caudal artery, showed concentration-dependent contractile responses to S6c which were further augmented after 5 days of culture. The ET-1-induced responses were only slightly affected by organ culture. Contractions induced by S6c were more enhanced in small arteries and veins than in larger arteries. Furthermore, the S6c-induced response was more pronounced in the mesenteric region as compared to the hindlimb. In fresh mesenteric arterial segments FR139317 (ETA receptor antagonist) and bosentan (ETA/ETB receptor antagonist) but not IRL 2500 (ETB receptor antagonist) shifted the ET-1-induced concentration-response curve in parallel to the right. In contrast, after organ culture the S6c-induced concentration-response curves were shifted parallel to the right in the following potency order: IRL 2500 > bosentan > FR139317. CONCLUSION During normal conditions, the ETA receptor is the dominating mediator of endothelin-induced contraction in eight different vascular regions. Furthermore, this study indicates that most of the vessels have the ability to develop contractile ETB receptors and that this plasticity differs in vascular regions.

Psoriasin, one of several new proteins identified in nasal lavage fluid from allergic and non-allergic individuals using 2-dimensional gel electrophoresis and mass spectrometry

BackgroundExtravasation and luminal entry of plasma occurs continuously in the nose. This process is markedly facilitated in patients with symptomatic allergic rhinitis, resulting in an increased secretion of proteins. Identification of these proteins is an important step in the understanding of the pathological mechanisms in allergic diseases. DNA microarrays have recently made it possible to compare mRNA profiles of lavage fluids from healthy and diseased patients, whereas information on the protein level is still lacking.MethodsNasal lavage fluid was collected from 11 patients with symptomatic allergic rhinitis and 11 healthy volunteers. 2-dimensional gel electrophoresis was used to separate proteins in the lavage fluids. Protein spots were picked from the gels and identified using mass spectrometry and database search. Selected proteins were confirmed with western blot.Results61 spots were identified, of which 21 were separate proteins. 6 of these proteins (psoriasin, galectin-3, alpha enolase, intersectin-2, Wnt-2B and hypothetical protein MGC33648) had not previously been described in nasal lavage fluids. The levels of psoriasin were markedly down-regulated in allergic individuals. Prolactin-inducible protein was also found to be down-regulated, whereas different fragments of albumin together with Ig gamma 2 chain c region, transthyretin and splice isoform 1 of Wnt-2B were up-regulated among the allergic patients.ConclusionThe identification of proteins in nasal lavage fluid with 2-dimensional gelelectrophoresis in combination with mass spectrometry is a novel tool to profile protein expression in allergic rhinitis and it might prove useful in the hunt for new therapeutic targets or diagnostic markers for allergic diseases. Psoriasin is a potent chemotactic factor and its down-regulation during inflammation might be of importance for the outcome of the disease.