Cathelicidin LL-37 in bronchoalveolar lavage and epithelial lining fluids from healthy individuals and sarcoidosis patients.

Sarcoidosis is a granulomatous disease of unknown etiology most often characterized by pulmonary manifestations. Changes in an innate immune system, involving antimicrobial peptides, have been noted during the course of pulmonary sarcoidosis. This study focuses on the level of LL-37 peptide, the only human cathelicidin, additionally characterized by a wide range of pleiotropic activities, in pulmonary sarcoidosis. A cross-sectional study was conducted in groups of 32 patients with sarcoidosis and 12 healthy individuals. Bronchoalveolar lavage fluid (BALF) sampling, followed by LL-37 measurements by mass spectrometry combined with previous immunoaffinity purification, was performed. Based on urea levels, concentrations of LL-37 in epithelial lining fluid (ELF) were calculated. The levels of LL-37 peptide in BALF samples derived from patients with pulmonary sarcoidosis (median: 17.45 pg/ml, 25th-75th percentile: 8.05-28.33 pg/ml) were significantly higher compared to the healthy group (median: 6.38 pg/ml, 25th-75th percentile: 4.90-11.55 pg/ml) (U Mann-Whitney test, p=0.04). Assessment of LL-37 in ELF confirmed the differences across the groups that were observed in BALF. The level of LL-37 in patients with sarcoidosis (median: 2.25 ng/ml, 25th-75th percentile: 1.03-5.06 ng/ml) was again higher compared to healthy individuals (median: 0.62 ng/ml, 25th-75th percentile: 0.43-2.17 ng/ml) (p=0.06, Mann-Whitney U test). The results of this study demonstrate that the level of LL-37 peptide is elevated in pulmonary compartment affected by sarcoidosis. This might have a meaning in the pathomechanism of the disease, especially taking into consideration versatile activity of human cathelicidin revealed in numerous experimental studies during the last years.

Cathelicidin LL-37 in bronchoalveolar lavage and epithelial lining fluids from COPD patients and healthy individuals.

Innate immunity is currently under scope of interest concerning its role in the development of chronic obstructive pulmonary disease (COPD). Antimicrobial peptides constitute a potent part of this fast response system. Here, we focus on the role of a specific antimicrobial peptide, the only human cathelicidin, the pleiotropic LL-37 peptide, in the development of COPD under clinical conditions. A cross-sectional study was conducted in groups of 43 patients with COPD (previously classified according to GOLD) and 12 healthy individuals. Bronchoalveolar lavage fluid (BALF) sampling, followed by LL-37 measurements by mass spectrometry combined with previous immunoaffinity purification, was performed. Based on urea levels, concentrations of LL-37 in epithelial lining fluid (ELF) were calculated. Additionally, an antimicrobial assay of growth inhibition of two bacterial species, often involved in COPD development mechanisms, by purchased LL-37 was conducted. Altogether, 55 BALF samples were analyzed. LL-37 levels were significantly higher in BALF from patients in early stages of COPD (GOLD I-II) compared to BALFs from healthy individuals. The same was true for ELF. Cathelicidin’s concentration was significantly lower in both BALF and ELF from patients in advanced COPD (GOLD III-IV). The significantly elevated LL-37 levels both in BALF and ELF in patients with COPD at stage GOLD I-II together with reduced levels in advanced (COPD stage III-IV) further supports the innate immunity involvement in COPD pathology and suggests a profound change in non-specific immunity during the disease progression.

CD1c(+) immature myeloid dendritic cells are predominant in cord blood of healthy neonates.

It has been suggested lately that some types of antigen presenting cells-myeloid dendritic (DC-1) cells can differentiate the immune response towards Th1 type immunity, whereas lymphoid cells (DC-2) can stimulate Th2 type immunity. It has been observed that neonates are deficient in Th1 response. The purpose of our study was to estimate the proportions of immature myeloid (CD1c(+)) and lymphoid (BDCA-2(+), BDCA-4(+)) dendritic cells and the CD1c(+):BDCA-2(+) cell ratio in cord blood of healthy neonates in comparison with dendritic cells of healthy adults. Thirty healthy neonates born from normal pregnancies and 30 healthy adults were included in the study. The dendritic cells were isolated from cord and peripheral blood, stained with anti-CD1c, anti-BDCA-2, anti-BDCA-4, anti-CD123 and anti-CD19 monoclonal antibodies and estimated using flow cytometry. The percentage of CD1c(+) dendritic cells in cord blood of healthy newborns did not differ significantly when compared to those in peripheral blood of healthy adults. The percentages of cord blood BDCA-2(+) and BDCA-4(+) dendritic cells of neonates were significantly lower when compared to lymphoid dendritic cells in peripheral blood of adults. The CD1c(+):BDCA-2(+) ratio was significantly higher in cord blood of neonates in comparison with CD1c(+):BDCA-2(+) ratio in adult's blood. Myeloid and lymphoid dendritic cells may be involved in the immune regulation during fetal development. Immature myeloid dendritic cells are predominant in cord blood of healthy neonates. Immature lymphoid dendritic cells are not the major population of dendritic cells in cord blood.

Blood myeloid and lymphoid dendritic cells are stable during the menstrual cycle but deficient during mid-gestation.

The aim of this study was to estimate the populations of peripheral blood myeloid and lymphoid dendritic cells (CD1c(+), BDCA-2(+), BDCA-4(+)) and the CD1c(+):BDCA-2(+) ratio in phases of the ovarian cycle and in normal pregnant patients. 18 non-pregnant women and 17 normal pregnant women were included. Dendritic cells were isolated from peripheral blood, stained with monoclonal antibodies (mAbs) against blood dendritic cell antigens (anti-BDCA-1, BDCA-2, BDCA-4) and estimated using flow cytometry. CD1c(+), BDCA-2(+) and BDCA-4(+) dendritic cells were present in the follicular and luteal phases of the ovarian cycle and in all trimesters of normal pregnancy. The percentages of CD1c(+) dendritic cells did not differ between the follicular and luteal phases of the ovarian cycle. The percentage of BDCA-2(+) dendritic cells was lower in the luteal phase of the ovarian cycle compared with the follicular phase, but the differences were not statistically significant. The CD1c(+):BDCA-2(+) cell ratio was significantly lower in the luteal phase compared with the follicular phase of the ovarian cycle. The numbers of dendritic cells were significantly lower in the second trimester when compared with the first and third trimesters of normal pregnancy. Furthermore, in the second trimester, the CD1c(+):BDCA-2(+) ratio was higher than in the other trimesters of normal pregnancy. All populations of dendritic cells and the CD1c(+):BDCA-2(+) ratio did not differ in the first and third trimesters of physiological pregnancy. Our results suggest that myeloid and lymphoid dendritic cells are not affected by steroid hormones during the menstrual cycle. The deficiency of peripheral blood dendritic cells observed during the second trimester of normal pregnancy can be associated with their migration to the uterus during the second physiological invasion by cytotrophoblast.

Myeloid and lymphoid dendritic cells in normal pregnancy and pre-eclampsia.

The aim of our study was to estimate the populations of peripheral blood myeloid and lymphoid dendritic cells (CD1c+, BDCA-2+) and the CD1c+ : BDCA-2+ ratio in normal pregnant women and in patients with pre-eclampsia. Fifteen women in the first, second and third trimesters of normal pregnancy, and 25 patients with pre-eclampsia were included in the study. The dendritic cells were isolated from peripheral blood, stained with monoclonal antibodies against blood dendritic cell antigens (anti-CD1c, anti-BDCA-2) and estimated using the flow cytometric method. CD1c+ and BDCA-2+ dendritic cells were present in women during all trimesters of physiological pregnancy and in pre-eclamptic patients. It was observed that the numbers of dendritic cells were significantly lower in the second trimester when compared with the first and third trimesters of normal pregnancy. Furthermore, in the second trimester, CD1c+ : BDCA-2+ ratio was higher than in the other trimesters of physiological pregnancy. All populations of dendritic cells and CD1c+ : BDCA-2+ ratio did not differ in the first and third trimesters of normal pregnancy. The percentage of BDCA-2+ dendritic cells was significantly lower in pre-eclampsia in comparison with healthy women in the third trimester of physiological pregnancy, while CD1c+ : BDCA-2+ ratio was significantly higher in pre-eclamptic patients when compared with control groups. We concluded that dendritic cells may be involved in the immune regulation during physiological pregnancy. CD1c+ and BDCA-2+ cells can influence the Th2 phenomenon which is observed during physiological pregnancy. Furthermore, it seems possible that lower BDCA-2+ cells percentage and higher CD1c+ : BDCA-2+ ratio can be associated with increased Th1-type immunity in patients with pre-eclampsia.