Viral load in patients infected with pandemic H1N1 2009 influenza A virus.

Viral shedding profile of infections caused by the pandemic H1N1 2009 influenza A virus has not been reported. The aim of this study was to determine the viral load in different body sites. Viral loads of pandemic H1N1 virus in respiratory specimens, stool, urine, and serum were determined by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR).

Clinical characteristics and genotype-phenotype correlation in 62 patients with X-linked agammaglobulinemia.

Introduction: X-linked agammagobulinemia (XLA) is a primary immunodeficiency disorder caused by Bruton's tyrosine kinase (Btk) gene mutation. Recent studies suggested genotype-phenotype correlation in XLA, but a definitive association remains controversial.

Patients And Methods: We examined the relationship between specific Btk gene mutations and severity of clinical presentation in 62 patients with XLA.

Virologically confirmed population-based burden of hospitalization caused by influenza A and B among children in Hong Kong.

Background: We sought to determine the virologically confirmed hospitalization rates associated with influenza virus infection among Hong Kong children.

Methods: Patients <18 years of age who lived on Hong Kong Island (a separate island within Hong Kong) and were admitted to either of the only 2 public hospitals on the island for a febrile acute respiratory infection on 1 fixed day of the week in each hospital from October 2003 through September 2006 were prospectively recruited. These 2 hospitals together accounted for 72.

Clinical and molecular epidemiology of human rhinovirus C in children and adults in Hong Kong reveals a possible distinct human rhinovirus C subgroup.

Background: A novel human rhinovirus (HRV) species, HRV-C, was recently discovered, but its clinical features and epidemiology, compared with HRV-A and HRV-B, remains poorly understood, especially in adults.

Methods: One thousand two hundred nasopharyngeal aspirate samples obtained from hospitalized children and adults during a 1-year period were subject to reverse-transcriptase polymerase chain reaction to detect HRV. The clinical and molecular epidemiology of the 3 HRV species was analyzed.

Efficient induction and expansion of human alloantigen-specific CD8 regulatory T cells from naive precursors by CD40-activated B cells.

Although recent studies have focused on CD4(+) regulatory T cells (Treg), CD8(+) Treg have also been reported to play important roles in the induction and maintenance of immune tolerance. Adoptive transfer of CD8(+) Treg in rodents or induction of CD8(+) Treg in humans can prevent or treat allograft rejection and autoimmune diseases. However, no approaches have been reported for the generation of human Ag-specific CD8(+) Treg at a practical scale for clinical use.

Phosphoantigen-expanded human gammadelta T cells display potent cytotoxicity against monocyte-derived macrophages infected with human and avian influenza viruses.

Background: Influenza virus is a cause of substantial annual morbidity and mortality worldwide. The potential emergence of a new pandemic strain (eg, avian influenza virus) is a major concern. Currently available vaccines and anti-influenza drugs have limited effectiveness for influenza virus infections, especially for new pandemic strains.

In-depth cDNA library sequencing provides quantitative gene expression profiling in cancer biomarker discovery.

Quantitative gene expression analysis plays an important role in identifying differentially expressed genes in various pathological states, gene expression regulation and co-regulation, shedding light on gene functions. Although microarray is widely used as a powerful tool in this regard, it is suboptimal quantitatively and unable to detect unknown gene variants. Here we demonstrated effective detection of differential expression and co-regulation of certain genes by expressed sequence tag analysis using a selected subset of cDNA libraries.

Influenza virus directly infects human natural killer cells and induces cell apoptosis.

Influenza is an acute respiratory viral disease that is transmitted in the first few days of infection. Evasion of host innate immune defenses, including natural killer (NK) cells, is important for the virus's success as a pathogen of humans and other animals. NK cells encounter influenza viruses within the microenvironment of infected cells and are important for host innate immunity during influenza virus infection.

Identification of novel FBN1 and TGFBR2 mutations in 65 probands with Marfan syndrome or Marfan-like phenotypes.

Marfan syndrome is an autosomal dominant connective tissue disorder, and mutations in the FBN1 and TGFBR2 genes have been identified in probands with MFS and related phenotypes. Using DHPLC and sequencing, we studied the mutation spectrum in 65 probands with Marfan syndrome and related phenotypes. A total of 24 mutations in FBN1 were identified, of which 19 (nine missense, six frameshift, two nonsense and two affecting splice junctions) were novel.

Immunogenicity and safety of intradermal versus intramuscular route of influenza immunization in infants less than 6 months of age: a randomized controlled trial.

We aimed to explore intradermal influenza vaccination in infants <6 months. One hundred twenty-six infants 2-3 months of age were randomized to receive either two doses, 1 month apart, of 0.25 ml of a trivalent inactivated influenza vaccine (7.

Toll-like receptors, chemokine receptors and death receptor ligands responses in SARS coronavirus infected human monocyte derived dendritic cells.

Background: The SARS outbreak in 2003 provides a unique opportunity for the study of human responses to a novel virus. We have previously reported that dendritic cells (DCs) might be involved in the immune escape mechanisms for SARS-CoV. In this study, we focussed on the gene expression of toll-like receptors (TLRs), chemokine receptors (CCRs) and death receptor ligands in SARS-CoV infected DCs.

Clinical and molecular characteristics of 35 Chinese children with Wiskott-Aldrich syndrome.

Background: Wiskott-Aldrich syndrome (WAS) is a rare primary immunodeficiency disease, with an incidence of 4/1,000,000 live male births. In China, an estimated number of 35 babies with WAS are born each year, but likely many remain undiagnosed.

Objectives: The objectives of study were to review the clinical and molecular characteristics of a cohort of Chinese children with WAS and to describe the long-term outcome of those who underwent hematopoietic stem cell transplant (HSCT).

ITGAM is associated with disease susceptibility and renal nephritis of systemic lupus erythematosus in Hong Kong Chinese and Thai.

ITGAM was recently found to be associated with systemic lupus erythematosus (SLE) in populations of not only European ancestry, but also in Hispanic- and African-Americans, Mexicans and Colombians. The risk alleles in the gene, however, were found to be monomorphic in two Asian populations examined: Japanese and Korean. In this study, using a collection of 910 SLE patients and 2360 controls from Chinese living in Hong Kong, analyzed by both genome-wide association and direct sequencing, we confirmed the association of the same risk alleles in ITGAM with the disease.

Brachydactyly A-1 mutations restricted to the central region of the N-terminal active fragment of Indian Hedgehog.

Mutations in the gene Indian Hedgehog (IHH) that cause Brachydactyly A-1 (BDA1) have been restricted to a specific region of the N-terminal active fragment of Indian Hedgehog involving codons 95, 100, 131, and 154. We describe two novel mutations in codons 128 and 130, not previously implicated in BDA1. Furthermore, we identified an independent mutation at codon 131 and we also describe a New Zealand family, which carries the 'Farabee' founder mutation and haplotype.

Clinical and molecular epidemiology of human parainfluenza virus 4 infections in hong kong: subtype 4B as common as subtype 4A.

In this 1-year study, 35 (1.2%) of 2,912 nasopharyngeal aspirates were positive for human parainfluenza virus 4 (HPIV4) by reverse transcription-PCR. Patients with HPIV4 infection were mainly young children and immunocompromised adults.

Insulin-like growth factor I promotes cord blood T cell maturation through monocytes and inhibits their apoptosis in part through interleukin-6.

Background: The functional immaturity of T cells contributes to the susceptibility of neonates to infections and the less severe graft-versus-host disease associated with cord blood (CB) transplantation. We have previously reported that insulin-like growth factor - I (IGF-I) promotes the phytohaemagglutinin (PHA)-induced CB T cell maturation and inhibits their apoptosis in mononuclear cell (MC) culture. We hypothesized that the effects of IGF-I may be mediated by accessory cells and soluble factors.

Promoter-sharing by different genes in human genome--CPNE1 and RBM12 gene pair as an example.

Background: Regulation of gene expression plays important role in cellular functions. Co-regulation of different genes may indicate functional connection or even physical interaction between gene products. Thus analysis on genomic structures that may affect gene expression regulation could shed light on the functions of genes.

Prolonged exposure to bacterial toxins downregulated expression of toll-like receptors in mesenchymal stromal cell-derived osteoprogenitors.

Background: Human mesenchymal stromal cells (MSCs, also known as mesenchymal stem cells) are multipotent cells with potential therapeutic value. Owing to their osteogenic capability, MSCs may be clinically applied for facilitating osseointegration in dental implants or orthopedic repair of bony defect. However, whether wound infection or oral microflora may interfere with the growth and osteogenic differentiation of human MSCs remains unknown.

MHC expression kinetics and immunogenicity of mesenchymal stromal cells after short-term IFN-gamma challenge.

Objective: Under the influence of interferon-gamma (IFN-gamma), mesenchymal stromal cells (MSCs) are conditional antigen-presenting cells, which have immunosuppressive potential. Apart from IFN-gamma upregulation of major histocompatibility complexes class I and II (MHC-I and MHC-II) expression, the underlying kinetics and mechanisms have not been described previously. This information is helpful to delineate how human MSCs can be modulated by IFN-gamma in different clinical scenarios.

Inflammatory gene polymorphisms and susceptibility to kawasaki disease and its arterial sequelae.

Objective: We tested the hypothesis that single-nucleotide polymorphisms of inflammatory genes C-reactive protein (CRP) and tumor necrosis factor alpha (TNF-alpha) may exert influence on susceptibility to Kawasaki disease and its arterial sequelae.

Methods: We analyzed the CRP +1444 C-->T and TNF-alpha -308 G-->A polymorphisms in 167 patients aged 8.9 +/- 4.

Ganoderma lucidum polysaccharides can induce human monocytic leukemia cells into dendritic cells with immuno-stimulatory function.

Background: Previous studies demonstrated Ganoderma lucidum polysaccharides (GL-PS), a form of bioactive beta-glucan can stimulate the maturation of monocyte-derived dendritic cells (DC). The question of how leukemic cells especially in monocytic lineage respond to GL-PS stimuli remains unclear.

Results: In this study, we used in vitro culture model with leukemic monocytic cell-lines THP-1 and U937 as monocytic effectors cells for proliferation responses and DCs induction.

Hyperinduction of cyclooxygenase-2-mediated proinflammatory cascade: a mechanism for the pathogenesis of avian influenza H5N1 infection.

The mechanism for the pathogenesis of H5N1 infection in humans remains unclear. This study reveals that cyclooxygenase-2 (COX-2) was strongly induced in H5N1-infected macrophages in vitro and in epithelial cells of lung tissue samples obtained during autopsy of patients who died of H5N1 disease. Novel findings demonstrated that COX-2, along with tumor necrosis factor alpha and other proinflammatory cytokines were hyperinduced in epithelial cells by secretory factors from H5N1-infected macrophages in vitro.

Low serum mannose-binding lectin level increases the risk of death due to pneumococcal infection.

Background: Previous studies have shown associations between low mannose-binding lectin (MBL) level or variant MBL2 genotype and sepsis susceptibility. However, MBL deficiency has not been rigorously defined, and associations with sepsis outcomes have not been subjected to multivariable analysis.

Methods: We reanalyzed MBL results in a large cohort with use of individual data from 4 studies involving a total of 1642 healthy control subjects and systematically defined a reliable deficiency cutoff.

Efficient generation of human alloantigen-specific CD4+ regulatory T cells from naive precursors by CD40-activated B cells.

CD4(+)CD25(+)Foxp3(+) regulatory T cells (Treg) play an important role in the induction and maintenance of immune tolerance. Although adoptive transfer of bulk populations of Treg can prevent or treat T cell-mediated inflammatory diseases and transplant allograft rejection in animal models, optimal Treg immunotherapy in humans would ideally use antigen-specific rather than polyclonal Treg for greater specificity of regulation and avoidance of general suppression. However, no robust approaches have been reported for the generation of human antigen-specific Treg at a practical scale for clinical use.