To determine whether lentinan could upregulate the expression of human-beta-defensin-2(HBD-2) in pulmonary epithelial cells (SPC-A-1), we stimulated pulmonary epithelial cells with lentinan and detected the expression of HBD-2mRNA by RT-PCR test. The results demonstrated that the expression of HBD-2mRNA in SPC-A-1 could be induced by lentinan in a concentration and time-dependent manner.
Adjuvants, Immunologic ; pharmacology ; Epithelial Cells ; metabolism ; Humans ; Lentinan ; pharmacology ; Lung ; cytology ; metabolism ; RNA, Messenger ; genetics ; metabolism ; beta-Defensins ; genetics ; metabolism

OBJECTIVE: To study the changes in the expression of rat beta-defensin-2 (RBD-2) gene in the lung tissue with P. aeruginosa (PA) pneumonia following tracheal mechanical ventilation (MV), and to evaluate the pathogenesis of ventilator-associated pneumonia (VAP). METHODS: A total of 58 normal healthy Sprague-Dawley rats, weighing between 280 and 320 g, were randomly divided into the control group and the conventional MV group (CMV). A tracheal catheter was inserted via mouth in every rat under urethane anesthesia. PA (1 MIC, 0.2 ml) was instilled into the tracheal in the control group. Rats of CMV group received MV (V(T)=12 ml/kg) through tracheal tube for 24 hours, and then were challenged intra-tracheally with PA (1 MIC, 0.2 ml). Fluid loss was replenished through intravenous infusion. The arterial catheter was used for hemodynamics, parameters were monitored, and arterial blood gases were determined. Samples of lung were harvested at 0 hours, 15 hours, 3 hours, 6 hours, 12 hours, 1 day, 3 days and 5 days, respectively, after bacterial challenge. The mRNA of RBD-2 was detected by reverse transcription-polymerase chain reaction (RT-PCR), and the protein levels were analyzed by Western blotting. RESULTS: Expression of RBD-2 mRNA and protein was lower in CMV group compared with the control 3 hours before instillation of bacteria. RBD-2 mRNA increased 3 hours after bacteria instillation, reaching the peak at 12-24 hours. No significant difference in RBD-2 expression between the control group and the CMV group within 3 hours, but it was significantly higher at 3 hours, 6 hours, 12 hours, 1 day, 3 days and 5 days in the control group than in the CMV group. The number of inflammatory cells infiltrating the bronchial submucous layer was significantly higher in the control group than in the CMV group (P<0.05). There was milder interstitial pulmonary edema and less red blood cells in the alveoli in the control group than in the CMV group. The mortality rate of the CMV group was 60%, which was significantly higher than that of the control group (20%, P<0.05). The positive rates of blood culture and bronchoalveolar lavage fluid (BALF) bacterial culture were also higher in the CMV group (P<0.05). The survival rate in CMV group (40%) was lower than that of the control group (P<0.05). CONCLUSION: The lowering of BD-2 gene and protein expression in the CMV group 3 hours after bacteria challenge might be one of the contributory factors in causing VAP.
Disease Models, Animal ; Lung/metabolism ; Lung/pathology ; Pneumonia, Ventilator-Associated/*metabolism ; Pneumonia, Ventilator-Associated/pathology ; RNA, Messenger/metabolism ; Random Allocation ; Rats, Sprague-Dawley ; beta-Defensins/genetics ; beta-Defensins/*metabolism

BACKGROUNDAntimicrobial peptides, including cathelicidin LL-37, human beta defensin (HBD)-2, and HBD-3, are important elements of the innate immune response and involved in modulation of the adaptive immunity, and they also play an important role in cutaneous defense against Mycobacterium tuberculosis.

METHODSThe fresh skin tissues and paraffin-embedded biopsy samples from three cutaneous tuberculosis, two tuberculids, and ten healthy individuals were collected. The expressions of LL-37, HBD-2, and HBD-3 mRNA in the lesions of three cutaneous tuberculosis and two tuberculids were detected by quantitative real-time polymerase chain reaction; the protein expressions were detected by immunohistochemistry and Western blotting methods.

RESULTSThe expressions of LL-37 mRNA and protein in the lesions of cutaneous tuberculosis and tuberculids were similar to that of normal skin. The expression of HBD-2 mRNA had an increasing trend in the lesions of cutaneous tuberculosis and tuberculids compared with that of normal skin; however, the expression of HBD-2 protein in the lesions of cutaneous tuberculosis had a decreasing trend compared with that of normal skin, and the expression of HBD-2 protein in the lesions of tuberculids was similar to that of normal skin. The expressions of HBD-3 mRNA and protein in lesions of cutaneous tuberculosis and tuberculids were similar to that of normal skin.

CONCLUSIONSOur study indicated that the expression of HBD-2 and HBD-3 mRNA and protein in lesions of cutaneous tuberculosis may be not consistent with that of tuberculids. However, an inherent limitation of the present study was that the sample size was small, and the roles and regulation mechanisms of LL-37, HBD-2, and HBD-3 in cutaneous tuberculosis and tuberculids need to be further investigated.

Adult ; Aged ; Antimicrobial Cationic Peptides ; genetics ; Female ; Humans ; Male ; Middle Aged ; RNA, Messenger ; analysis ; Tuberculosis, Cutaneous ; metabolism ; beta-Defensins ; genetics

OBJECTIVETo study the expression of human beta-defensin-3 (hBD-3) induced by lipopolysaccharide (LPS) in human bronchial epithelial (HBE) cells, and explore the role of hBD-3 in respiratory infection.

METHODSHBE cells were stimulated with different concentrations of LPS (0.01, 0.1, 1 and 10 microg/mL). hBD-3 mRNA expression was detected by RT-PCR 2 hrs later. hBD-3 protein expression was detected by Western blot 4 hrs later.

RESULTShBD-3 mRNA and protein was weakly expressed in normal HBE cells. LPS stimulation resulted in a significant increase of hBD-3 mRNA and protein expression (p<0.01). hBD-3 mRNA and protein expression increased with increasing LPS concentrations. There were significant differences in the hBD-3 mRNA and protein expression in cells stimulated by different concentrations of LPS (p<0.05).

CONCLUSIONSLPS can induce hBD-3 expression in a dose-dependent manner. hBD-3 might play a role in initial defensive reaction against bacterial invasion.

Bronchi ; drug effects ; metabolism ; Dose-Response Relationship, Drug ; Humans ; Lipopolysaccharides ; toxicity ; RNA, Messenger ; analysis ; beta-Defensins ; analysis ; genetics

To evaluate the association of Toll-like receptors (TLRs), antimicrobial peptides (AMPs) and vitamin D receptors (VDRs) in psoriasis, lesional (PP) and perilesional skin (PN) from psoriasis, atopic dermatitis (AD) patients and healthy controls (NN) were studied by immunohistochemistry. Compared with PN, AD and NN skin, dysregulated expression of TLRs, AMPs and VDR was detected in PP skin. Noteworthy, our results showed altered correlation between TLR2 and VDR expression in PP and PN skin. Human beta defensin 2 (HBD2) and cathelicidin (LL-37) expressions in the PP skin were higher in serum vitamin D sufficient (VDS) groups than serum vitamin D deficient (VDD) groups. Negative correlation was found between TLR2 and VDR expression in the PP skin of VDD groups. However, positive correlation was noted in the PP skin of VDS groups. Based on the present results, therapies targeting the activity of TLRs, AMPs and vitamin D, including modulation of the TLR-VDR pathways, might provide new therapeutic approaches to the psoriasis and other inflammatory skin diseases.
Anti-Infective Agents/*metabolism ; Antimicrobial Cationic Peptides/*metabolism ; Female ; Humans ; Male ; Psoriasis/*metabolism ; Receptors, Calcitriol/metabolism ; Toll-Like Receptors/*metabolism ; Vitamin D/*blood ; beta-Defensins/metabolism

No abstract available.
Crohn Disease/*drug therapy/*metabolism ; Female ; Forkhead Transcription Factors/*metabolism ; Gastrointestinal Agents/*therapeutic use ; Humans ; Infliximab/*therapeutic use ; Leukocytes, Mononuclear/*metabolism ; Male ; Membrane Proteins/*metabolism ; beta-Defensins/*metabolism

Adolescent ; Adult ; Chronic Disease ; Female ; Humans ; Male ; Middle Aged ; Nasal Mucosa ; metabolism ; Rhinitis ; metabolism ; Sinusitis ; metabolism ; Young Adult ; beta-Defensins ; metabolism

Idiopathic asthenozoospermia, a common factor in male infertility, is characterized by altered sperm motility function in fresh ejaculate. Although the β-defensin 126 (DEFB126) protein is associated with asthenozoospermia, DEFB126 gene polymorphisms have not been extensively studied. Therefore, the association between DEFB126 gene polymorphisms and asthenozoospermia requires further investigation. Screening was performed by semen analysis, karyotype analysis, and Y microdeletion detection, and 102 fertile men and 106 men with asthenozoospermia in Chengdu, China, were selected for DEFB126 gene sequence analyses. Seven nucleotide mutations and two nucleotide deletions in the DEFB126 gene were detected. rs11467417 (317-318 del/del), rs11467497 (163-166 wt/del), c.152T>C, and c.227A>G were significantly different between the control and asthenozoospermia groups, likely representing high-risk genetic factors for asthenozoospermia among males. DEFB126 expression was not observed in sperm with rs11467497 homozygous deletion and was unstable in sperm with rs11467417 homozygous deletion. The rs11467497 four-nucleotide deletion leads to truncation of DEFB126 at the carboxy-terminus, and the rs11467417 binucleotide deletion produces a non-stop messenger RNA (mRNA). The above deletions may be responsible for male hypofertility and infertility by reducing DEFB126 affinity to sperm surfaces. Based on in silico analysis, the amino acids 51M and 76K are located in the highly conserved domain; c.152T>C (M51T) and c.227A>G (K76R) are predicted to be damaging and capable of changing alternative splice, structural and posttranslational modification sites of the RNA, as well as the secondary structure, structural stability, and hydrophobicity of the protein, suggesting that these mutations are associated with asthenozoospermia.
Male ; Humans ; Asthenozoospermia/metabolism* ; Sperm Motility/genetics* ; Homozygote ; Polymorphism, Single Nucleotide ; Semen ; Sequence Deletion/genetics* ; Spermatozoa/metabolism* ; Nucleotides/metabolism* ; beta-Defensins/metabolism*

OBJECTIVETo observe the expressions of human beta-defensin 1 and 2 (hBD-1 and hBD-2) in nasal mucosa before and after the endoscopic sinus surgery and investigate the effects of hBD-1 and hBD-2 on the healing process after the surgery.

METHODSThe patients undergoing endoscopic sinus surgery for chronic sinusitis were divided into 3 groups according to the response to the surgery, namely cured group, response group and non-response group. With those from healthy control subjects as the control, nasal mucosa samples were collected from the patients at 1 week, 2 weeks, 1 month, 3 months and 6 months after the surgery for detection of hBD-1 and hBD-2 mRNA and protein expressions by RT-PCR and Western blotting.

RESULTShBD-1 and hBD-2 were expressed in both normal and chronic sinusitis mucosa, but the expression levels varied significantly between the individuals. The expression levels of hBD-2 was significantly correlated to the patients' response to the surgical treatment (P<0.05). hBD-1 showed slight differences between the individuals, but was not associated with the patients' prognosis.

CONCLUSIONThe expressions of hBD-2 mRNA and protein are significantly increased in patients with good response to endoscopic sinus surgery for chronic sinusitis, suggesting the value of hBD-2 as an indicator of the patients' prognosis.

Case-Control Studies ; Chronic Disease ; Endoscopy ; Humans ; Nasal Mucosa ; metabolism ; Postoperative Period ; Prognosis ; RNA, Messenger ; genetics ; Sinusitis ; metabolism ; surgery ; beta-Defensins ; metabolism

For the purpose of detecting the HBD-2 expression at protein level, the recombinant prokaryotic expression vector pGEX-1lambdaT-HBD-2 was constructed and the E. coli-based product of GST-HBD-2 fusion protein was prepared. When rabbit was immunized with the fusion protein, the anti-serum against HBD-2 was produced. After caprylic acid and ammonium sulfate precipitation, high titer of specific polyclonal antibody against HBD-2, which was detected by ELISA and Western blot, was obtained. This result suggests that recombinant peptide fusion protein could be used instead of the conjugate of peptide-albumin or peptide-thyroid globulin to produce antibody. The obtained antibodies could be used for revealing the tissue distribution of HBD-2 and the regulation of its gene expression.
Animals ; Antibodies ; isolation & purification ; metabolism ; Blotting, Western ; Enzyme-Linked Immunosorbent Assay ; Escherichia coli ; metabolism ; Immunization ; Rabbits ; Recombinant Fusion Proteins ; immunology ; beta-Defensins ; immunology