Immune response to seasonal influenza A virus infection: a proteomic approach.

BACKGROUND AND AIMS: Influenza viruses cause respiratory infection in humans and result in substantial illness, death, and economic burden. To date, however, the mechanisms by which these viruses cause disease are not fully understood. METHODS: To investigate the proteomic profile of children infected with seasonal influenza A virus, nasal aspirates derived from children (n = 12) experiencing flu symptoms caused by seasonal influenza A virus were analyzed using two-dimensional electrophoresis (2-DE). Control nasal samples were taken from the same group of children 8-10 weeks later when they were symptom free. RESULTS: Analysis of the 2-DE gels revealed eight spots differentially expressed, which were further analyzed using mass spectrometry. Ten proteins were found to be differentially upregulated in the infected children including PLUNC, cystatin S, cystatin SA, S100A9, lipocalin 1 fragments (n = 2), truncated lactotransferrin, two immunoglobulin (Ig) kappa fragments and one immunoglobulin (Ig) lambda fragment. CONCLUSIONS: Our findings reveal that the composition of nasal secretions in influenza virus respiratory infections is different from that when children are healthy and may provide further insights into the pathogenesis of respiratory infections caused by seasonal influenza A viruses.

Galectin-10 is released in the nasal lavage fluid of patients with aspirin-sensitive respiratory disease.

The aim of this work was to determine the presence of galectin-10 in nasal lavage fluid (NLF) of patients with aspirin-sensitive respiratory disease (ASRD) before and after challenge with L-ASA (aspirin) by ELISA. Fifteen ASRD patients, ten aspirin-tolerant asthmatics (ATA), and fifteen healthy controls (HC) were studied. The baseline presence of Galectin-10 in PBMC was determined using real time PCR. Galectin-10 was evaluated in tissue of nasal polyps by western blot. Our results showed a lower expression in PBMC of ASRD patients than in ATA and healthy controls. However, a higher concentration of galectin-10 in NLF was found in ASRD patients before and after L-ASA challenge; western blot confirmed a high expression of galectin-10 in tissue from nasal polyps obtained from ASRD patients. Our results suggest a probable role of galectin-10 in the inflammatory response observed in ASRD patients; however, confirmatory studies are needed.

Chemokine (C-X-C motif) ligand 12/stromal cell-derived factor-1 is associated with leukocyte recruitment in asthma.

BACKGROUND: Asthma is characterized by allergic airway inflammatory response involving extensive leukocyte infiltration. The stromal cell-derived factor (SDF)-1 or chemokine (C-X-C motif) ligand 12 (CXCL12) attracts a number of cells, including resting T lymphocytes, monocytes, CD34(+) stem cells, basophils, and mature eosinophils. To date, however, the potential role of CXCL12/SDF-1 in relation to leukocyte recruitment in asthma has not been previously examined, to our knowledge. METHODS: Levels of CXCL12/SDF-1 in the BAL fluid (BALF) of 15 subjects with asthma and 13 healthy subjects were measured by enzyme-linked immunosorbent assay. Immunohistochemistry was performed to identify the cellular source of this chemokine. RESULTS: CXCL12/SDF-1 concentrations were significantly elevated in BALF from subjects with asthma compared with normal subjects (median 845 pg/mL, range, 296-1,700 pg/mL vs median 55 pg/mL, range 25-97 pg/mL; P < .001). Concentrations of CXCL12/SDF-1 correlated with macrophages (r = 0.728, P < .01), lymphocytes (r = 0.651, P < .01), and eosinophils (r = 0.765, P < .01). By immunohistochemistry, CXCL12/SDF-1 was localized to the airway epithelium and to a lesser extent to mononuclear cells. CONCLUSION: CXCL12/SDF-1 is released in high concentration in BALF of patients with asthma. The finding that concentrations of this chemokine correlated with leukocyte numbers in BALF suggests that this chemokine may contribute to the cell recruitment in asthma.