Dong-Wook Ryang

Clinical efficacy of granulocyte transfusion therapy in patients with neutropenia-related infections

Granulocyte transfusions have been advocated by some for the treatment of severe, progressive infections in neutropenic patients who fail to respond to antimicrobial agents and recombinant hematopoietic growth factors. We conducted the current study to determine an appropriate method of granulocyte mobilization in healthy donors, and to evaluate the safety and efficacy of granulocyte transfusion therapy in patients with neutropenia-related infections. To mobilize granulocytes (n = 55), healthy normal donors were stimulated in one of the following ways: (1) dexamethasone, 3 mg/m2 intravenously 15 min prior to leukapheresis (n = 5); (2) granulocyte colony-stimulating factor (G-CSF), 5 μg/kg subcutaneously 12 to 14 h prior to collection (n = 37); or (3) G-CSF and dexamethasone (n = 13). The mean granulocyte yield from stimulation with G-CSF plus dexamethasone was significantly higher than from stimulation with dexamethasone or G-CSF alone. Twenty-five patients with severe neutropenia-related infections unresponsive to appropriate antimicrobial agents received a total of 55 granulocyte transfusions. The patients from whom fungi or Gram-negative organisms were isolated showed a more favorable response than those infected with Gram-positive organisms. However, the responses to the granulocyte transfusion therapy could not be correlated with the transfused dose, mobilization agents, or the 1 h or 24 h post-transfusion absolute neutrophil counts. We conclude that granulocyte transfusion therapy may be clinically useful for neutropenia-related infections by fungi or Gram-negative organisms.

Circulating mucosal-associated invariant T cell levels and their cytokine levels in healthy adults

Mucosal-associated invariant T (MAIT) cells have been reported to play an antimicrobial role in infectious diseases. However, little is known about age- and gender-related changes in circulating MAIT cell level and function in healthy population. The purposes of this study were to examine the level and cytokine production of circulating MAIT cells and their subsets in healthy adults and to investigate potential relationships between clinical parameters and MAIT cell levels or their subset levels. One hundred thirty-three healthy subjects were enrolled in this study. MAIT cells, their subset, and cytokine levels were measured by flow cytometry. Circulating MAIT cell levels were found to vary widely (0.19% to 21.7%) in the study subjects and to be significantly lower in elderly subjects (age, 61-92 years) than in young subjects (age, 21-40 years) (p<0.0005). No significant difference was found in the circulating MAIT cell levels between male and female subjects. A linear regression analysis revealed that circulating MAIT cell levels declined annually by 3.2% among men and 1.8% among women, respectively. Notably, the proportion of CD4+ MAIT cells increased with age, whereas that of CD8+ MAIT cells decreased with age. In addition, the production of interleukin (IL)-4 by MAIT cells was found to be significantly increased in elderly subjects and the ratio of interferon (IFN)-γ/IL-4 was lower as compared with young subjects, showing a Th1 to Th2 shift in cytokine profile in elderly subjects. Our data suggest that aging is associated with a reduction in circulating MAIT cells, accompanied with alterations in subset composition and cytokine profile.

Dysfunction of Natural Killer T Cells in Patients with Active Mycobacterium tuberculosis Infection

ABSTRACT Natural killer T (NKT) cells are known to play a protective role in the immune responses of mice against a variety of infectious pathogens. However, little is known about the detailed information of NKT cells in patients with Mycobacterium tuberculosis infection. The aims of this study were to examine NKT cell levels and functions in patients with active M. tuberculosis infection, to investigate relationships between NKT cell levels and clinical parameters, and to determine the mechanism responsible for the poor response to α-galactosylceramide (α-GalCer). NKT cell levels were significantly lower in the peripheral blood of pulmonary tuberculosis and extrapulmonary tuberculosis patients, and the proliferative responses of NKT cells to α-GalCer were also lower in patients, whereas NKT cell levels and responses were comparable in latent tuberculosis infection subjects and healthy controls. Furthermore, this NKT cell deficiency was found to be correlated with serum C-reactive protein levels. In addition, the poor response to α-GalCer in M. tuberculosis-infected patients was found to be due to increased NKT cell apoptosis, reduced CD1d expression, and a defect in NKT cells. Notably, M. tuberculosis infection was associated with an elevated expression of the inhibitory programmed death-1 (PD-1) receptor on NKT cells, and blockade of PD-1 signaling enhanced the response to α-GalCer. This study shows that NKT cell levels and functions are reduced in M. tuberculosis-infected patients and these deficiencies were found to reflect the presence of active tuberculosis.

The serological and genetic basis of the cis-AB blood group in Korea

Background and Objectives  The cis‐AB blood group is rare, although relatively common amongst Koreans. The serological characteristics and genetic basis of Korean cis‐AB blood donors were investigated.

Plasma proGRP Concentration is Sensitive and Specific for Discriminating Small Cell Lung Cancer from Nonmalignant Conditions or Non-small Cell Lung Cancer

To date, most clinical data on pro-gastrin-releasing peptide (proGRP) have been based on serum concentrations. This study evaluated the agreement between proGRP levels in fresh serum and plasma in patients with various lung diseases. Pairs of serum and EDTA plasma were collected from 49 healthy individuals. At the same time, EDTA plasma of 118 lung cancer patients and 23 patients with benign pulmonary diseases were prospectively collected. Compared to serum, plasma proGRP concentrations were higher by an average of 103.3%. Plasma proGRP was higher in malignancy (336.4 ± 925.4 pg/mL) than in benign conditions (40.1 ± 11.5 pg/mL). Small cell lung cancer (SCLC) patients showed higher levels of proGRP (1,256.3 ± 1,605.6 pg/mL) compared to other types of lung cancer. Based on the ROC curve analyses at a specificity of 95%, the diagnostic sensitivity of plasma proGRP was estimated to be 83.8% in distinguishing SCLC from all the other conditions, and 86.5% for discriminating SCLC from the nonmalignant cases. Among the SCLC cases, limited stage disease had lower levels of plasma proGRP than extensive disease. When measuring circulating levels of proGRP, the use of plasma is preferred over serum. Plasma proGRP has a potential marker for discriminating SCLC from nonmalignant conditions or non-small cell lung cancer.

Alteration of mitochondrial DNA sequence and copy number in nasal polyp tissue

This study was designed to investigate the possibility that mtDNA mutations might arise in inflammatory or chronically damaged nasal polyp tissue from 23 patients. Thirteen patients (57%) displayed nasal polyp tissue-specific mtDNA mutations in the hypervariable segment of the control region and cytochrome b gene, which were not found in the corresponding blood cells and/or adjacent normal tissue. Nasal polyp tissue-specific length heteroplasmic mutations were also detected in nucleotide position (np) 303-315 homopolymeric poly C track (39%), np 514-523 CA repeats (17%) and np 16184-16193 poly C track (30%). The average mtDNA copy number was about three times higher in nasal polyp tissue than in the corresponding peripheral blood cells and adjacent non-polyp tissues. The level of reactive oxygen species (ROS) was significantly higher in the nasal polyp tissues compared to those from the corresponding samples. High level of ROS in nasal polyp tissue may contribute to development of mtDNA mutations, which may play a crucial role in the vicious cycle of pathophysiology of nasal polyps.

Age- and gender-related differences in circulating natural killer T cells and their subset levels in healthy Korean adults.

Natural killer T (NKT) cells have been reported to play crucial roles in a variety of diseases, including infectious diseases, autoimmunity, and cancers. Previous studies have reported wide age- and/or sex-related variations in circulating NKT cell levels in healthy subjects, but reported results are discrepant. In this study, the authors examined NKT cell levels in the peripheral blood of healthy Korean subjects and investigated potential relationships between clinical parameters and NKT cells and their subset levels. One hundred and thirty-eight age- and sex-matched healthy subjects were enrolled in this study. NKT cell and NKT subset levels were measured by flow cytometry. Circulating NKT cell levels were found to vary widely (0.01-5.15%) in the study subjects and to be lower in men than in women (P<0.05). Notably, gender-related differences in NKT cell levels were more prominent in elderly subjects (P<0.05). Furthermore, alterations in NKT subset compositions were found in elderly men, in whom the proportion of CD4+ NKT cells was elevated and that of double-negative NKT cells was reduced. Our data suggest that circulating NKT cells and NKT subset levels are affected by age and gender in the Korean population.

A novel Bvar allele (547 G>A) demonstrates differential expression depending on the co-inherited ABO allele

Background and Objectives  Genetic analysis of group B donors in Korea was performed.

Increased angiogenesis and Fas-ligand expression are independent processes in acute myeloid leukemia.

We evaluated the clinical significance of tumor angiogenesis and Fas-ligand (FasL) expression using parameters including the microvessel count (MVC), vascular endothelial growth factor (VEGF) level, and FasL expression in patients with acute myeloid leukemia (AML). Paraffin-embedded bone marrow (BM) sections from 43 AML patients at diagnosis, 20 patients after subsequent induction therapy, and 18 controls with non-invasive lymphoma were stained immunohistochemically for von Willebrand factor (vWF) and FasL. VEGF in BM mononuclear cells from 32 AML patients at diagnosis and 10 controls, including bone marrow transplantation donors, was assayed by an ELISA method. We found that the mean MVC, VEGF level, and FasL expression in AML patients at diagnosis were significantly higher than those of controls, with a significant correlation between the MVC and VEGF levels (r=0.43). However, there were no correlations between FasL expression and MVC or VEGF level. The mean MVC and FasL expression after induction therapy were lower than those evaluated at diagnosis, but were higher than those of controls. There was a correlation between the MVC and percentage of BM blasts (r=0.479), but no correlation between the MVC, VEGF level, or FasL expression and other hematologic or clinical variables. Our findings provide evidence of increased angiogenesis and tumor immune escape in AML, and both angiogenesis and tumor immune escape are independent processes in AML.

Spectra of Chromosomal Aberrations in 325 Leukemia Patients and Implications for the Development of New Molecular Detection Systems

This study investigated the spectrum of chromosomal abnormalities in 325 leukemia patients and developed optimal profiles of leukemic fusion genes for multiplex RT-PCR. We prospectively analyzed blood and bone marrow specimens of patients with acute leukemia. Twenty types of chromosomal abnormalities were detected in 42% from all patients by commercially available multiplex RT-PCR for detecting 28 fusion genes and in 35% by cytogenetic analysis including FISH analysis. The most common cytogenetic aberrations in acute myeloid leukemia patients was PML/PARA, followed by AML1/MGT8 and MLL1, and in acute lymphoid leukemia patients was BCR/ABL, followed by TEL/AML1 and MLL1 gene rearrangement. Among the negative results for multiplex RT-PCR, clinically significant t(3;3)(q21;q26.2), t(8;14)(q24;q32) and i(17)(q10) were detected by conventional cytogenetics. The spectrum and frequency of chromosomal abnormalities in our leukemia patients are differed from previous studies, and may offer optimal profiles of leukemic fusion genes for the development of new molecular detection systems.