• IMMUNE NETWORK
• /
• v.12 no.3
• /
• pp.104-112
• /
• 2012

Silica is one of the most abundant compounds found in nature. Immoderate exposure to crystalline silica has been linked to pulmonary disease and crystalline silica has been classified as a Group I carcinogen. Ultrafine (diameter <100 nm) silica particles may have different toxicological properties compared to larger particles. We evaluated the effect of ultrafine silica nanoparticles on mouse bone marrow-derived dendritic cells (BMDC) and murine dendritic cell line, DC2.4. The exposure of dendritic cells (DCs) to ultrafine silica nanoparticles showed a decrease in cell viability and an induction of cell death in size- and concentration-dependent manners. In addition, in order to examine the phenotypic changes of DCs following co-culture with silica nanoparticles, we added each sized-silica nanoparticle along with GM-CSF and IL-4 during and after DC differentiation. Expression of CD11c, a typical DC marker, and multiple surface molecules such as CD54, CD80, CD86, MHC class II, was changed by silica nanoparticles in a size-dependent manner. We also found that silica nanoparticles affect inflammatory response in DCs in vitro and in vivo. Finally, we found that p38 and NF-${\kappa}B$ activation may be critical for the inflammatory response by silica nanoparticles. Our data demonstrate that ultrafine silica nanoparticles have cytotoxic effects on dendritic cells and immune modulation effects in vitro and in vivo.

• IMMUNE NETWORK
• /
• v.6 no.2
• /
• pp.67-75
• /
• 2006

Background: Cytotoxic function of killer cells is inhibited by specific recognition of class I MHC molecules on target cells by inhibitory killer Ig-like receptors (KIR) expressed on NK cells and some cytotoxic T cells. The inhibitory effect of KIR is accomplished by recruitment of SH2-containing protein tyrosine phosphatase (SHP) to the phosphotyrosine residues in the cytoplasmic tail. Methods: By in vitro coprecipitation experiments and transfection analysis, we investigated the association of KIR with an adaptor protein Shc in Jurkat T cells. Results: The cytoplasmic tail of KIR appeared to associate with an adaptor protein Shc in Jurkat T celilysates. Similar in vitro experiments showed that phosphorylated KIR cytoplasmic tail bound SHP-1 and Shc in Jurkat T cell lysates. The association of KIR with Shc was further confirmed by transfection analysis in 293T cells. Interestingly, however, Shc appeared to be replaced by SHP-2 upon engagement of KIR in 293T cells. Conclusion: Our data indicate that KIR associate with an adaptor protein Shc in Jurkat T cells, and suggest that KIR might have an additional role which is mediated by this adaptor protein.

• Asian-Australasian Journal of Animal Sciences
• /
• v.18 no.12
• /
• pp.1691-1695
• /
• 2005

The bovine lymphocyte antigen (BoLA)-DRB3 gene encodes cell surface glycoproteins that initiate immune responses by presenting processed antigenic peptides to CD4 T helper cells. DRB3 is the most polymorphic bovine MHC class II gene which encodes the peptide-binding groove. Since different alleles favour the binding of different peptides, DRB3 has been extensively evaluated as a candidate marker for associations with various bovine diseases and immunological traits. For that reason, the genetic diversity of the bovine class II DRB3 locus was investigated by polymerase chain reaction-restriction fragment length polymorphism method (PCR-RFLP). This study describes genetic variability in the BoLA-DRB3 in Iranian Golpayegani Cattle. Iranian Golpayegani Cows (n = 50) were genotyped for bovine lymphocyte antigen (BoLA)-DRB3.2 allele by polymerase chain reaction and restriction fragment length polymorphism method. Bovine DNA was isolated from aliquots of whole blood. A two-step polymerase chain reaction followed by digestion with restriction endonucleases RsaI, HaeIII and BstYI was conducted on the DNA from Iranian Golpayegani Cattle. In the Iranian Golpayegani herd studied, we identified 19 alleles.DRB3.2${\times}$16 had the highest allelic frequency (14%), followed by DRB3.2${\times}$7 (11%). Six alleles (DRB3.2${\times}$25, ${\times}$24, ${\times}$22, ${\times}$20, ${\times}$15, ${\times}$3) had frequencies = 2%. Although additional studies are required to confirm the present findings, our results indicate that exon 2 of the BoLA-DRB3 gene is highly polymorphic in Iranian Golpayegani Cattle.

• Journal of Animal Science and Technology
• /
• v.52 no.6
• /
• pp.451-457
• /
• 2010

The porcine MHC (Major Histocompatibility Complex), encoding the SLA (Swine Leukocyte Antigen) genes, is one of the most significant regions associated with immune rejection in relation to transplantation. In this study, three SLA class I (SLA-1, SLA-3, SLA-2) loci and three SLA class II (DRB1, DQB1, DQA) loci were investigated in the previously unidentified Korean native pig (KNP) population that was closely inbred in the Livestock Technology Research Station in Cheongyang, Korea. Total thirteen KNPs from four generations were genotyped for the SLA alleles and haplotypes were investigated using PCR-SSP (Sequence-Specific Primer) method. The results showed that all of these KNPs had Lr-56.30/56.30 homozygous haplotype, indicating high level of inbreeding in the SLA genes. The inbreeding status of these animals was also investigated using microsatellite (MS) markers. From the 50 MS markers investigated, 17 MS markers were fixed in all generations and the fixed alleles are increased as 26 loci for the fourth generation. Two MS markers, S0069 and SW173, were heterozygous for all the animals tested. Observed and expected heterozygosities were calculated and the average inbreeding coefficients for each generation were also calculated. In the fourth generation, the average inbreeding coefficients was 0.732 and this may increase with further inbreeding process. Analysis of the SLA haplotypes and MS alleles can give important information for breeding the pigs for xenotransplantation studies.

• The Journal of Korean Obstetrics and Gynecology
• /
• v.23 no.2
• /
• pp.57-70
• /
• 2010

Purpose: In this study, we investigated the effects of GDB(Gidaebang) on the immune response to establish the treatment mechanism of vaginitis. Methods: We examined the effects of GDB on the DCs(Dendritic cells) phenotypic and functional maturation. iDCs were cultured in the presence of GM-CSF and the generated iDCs were respectively stimulated by GDB or LPS as the control group for 24 hours. To evaluate the DCs phenotypic and functional maturation, we used flow cytometric analysis, RT-PCR and ELISA. Results: 1. GDB upregulated the expression of class II MHC and CD40 on DCs. 2. GDB upregulated the expression of CD80 and CD86 on DCs. 3. GDB induced cytokine IL-12 production and mRNA expression in DCs. Conclusion: These results suggest that GDB is able to improve the antigen-presenting capacity of DCs through the upregulation of their maturation, and might induce proliferation of T cells. In conclusion, this immunomodulatory properties of GDB may be useful in the treatment of vaginitis.

• IMMUNE NETWORK
• /
• v.20 no.5
• /
• pp.38.1-38.12
• /
• 2020

Dendritic cells (DCs) are professional antigen-presenting cells (APCs) that initiate both T-cell responses and tolerance. Tolerogenic DCs (tDCs) are regulatory DCs that suppress immune responses through the induction of T-cell anergy and Tregs. Because lactoferrin (LF) was demonstrated to induce functional Tregs and has a protective effect against inflammatory bowel disease, we explored the tolerogenic effects of LF on mouse bone marrow-derived DCs (BMDCs). The expression of CD80/86 and MHC class II was diminished in LF-treated BMDCs (LF-BMDCs). LF facilitated BMDCs to suppress proliferation and elevate Foxp3⁺ induced Treg (iTreg) differentiation in ovalbumin-specific CD4⁺ T-cell culture. Foxp3 expression was further increased by blockade of the B7 molecule using CTLA4-Ig but was diminished by additional CD28 stimulation using anti-CD28 Ab. On the other hand, the levels of arginase-1 and indoleamine 2,3-dioxygenase-1 (known as key T-cell suppressive molecules) were increased in LF-BMDCs. Consistently, the suppressive activity of LF-BMDCs was partially restored by inhibitors of these molecules. Collectively, these results suggest that LF effectively causes DCs to be tolerogenic by both the suppression of T-cell proliferation and enhancement of iTreg differentiation. This tolerogenic effect of LF is due to the reduction of costimulatory molecules and enhancement of suppressive molecules.

• IMMUNE NETWORK
• /
• v.8 no.4
• /
• pp.130-136
• /
• 2008

Background: Human cytomegalovirus UL18, a MHC class I homologue, has been considered a natural killer (NK) cell decoy. It ligates LIR-1/ILT2 (CD85j), an NK inhibitory receptor, to prevent lysis of infected target cells. However, precise role of UL18 to NK cell cytotoxicity is yet elusive. Difficulty in clarifying the function of UL18 lies in complication in detecting UL18 mainly due to low level expression of UL18 on the surface and gradual loss of its expression. Methods: To overcome this hurdle, cDNA of cytoplasmic tail-less UL18 was constructed and expressed in swine endothelial cell (SEC). The expression level and its stability in the cell surface were monitored with FACS analysis. Results: Surface expression of UL18 is up-regulated by removing cytoplasmic tail portion from UL18F (a full sequence of UL18). SECs transfected with a cDNA of UL18CY (a cytoplasmic tail-less UL18) stably expressed UL18 molecule on the surface without gradual loss of its expression during 6 week continuous cultures. In the NK cytotoxicity assay, UL18 functions either inhibiting or activating NK cell cytotoxicity according to the source of NK cells. We found that there is individual susceptibility in determining whether the engagement of NK cell and UL18 results in overall inhibiting or activating NK cell cytotoxicity. Conclusion: In this study, we found that cytoplasmic tail is closely related to the regulatory function for controlling surface expression of UL18. Furthermore, by constructing stable cell line in which UL18 expression is up-regulated and stable, we provided a useful tool to clarify exact functions of UL18 on various immune cells having ILT2 receptor.

• IMMUNE NETWORK
• /
• v.9 no.1
• /
• pp.27-33
• /
• 2009

Macrophages generated in vitro using macrophage-colony stimulating factor (M-CSF) and interleukin (IL)-6 from bone marrow cells (BM-Mp) are defective in antigen presenting cell (APC) function as shown by their ability to induce the proliferation of anti-CD3 mAb-primed syngeneic T cells. However, they do express major histocompatibility (MHC) class I and II molecules. accessory molecules and intracellular adhesion molecules. Here we demonstrate that the defective APC function of macrophages is mainly due to production of $TGF-{\beta}1$ by BM-Mp. Methods: Microarray analysis showed that $TGF-{\beta}1$ was highly expressed in BM-Mp, compared to a macrophage cell line, B6D. which exerted efficient APC function. Production of $TGF-{\beta}1$ by BM-Mp was confirmed by neutralization experiments of $TGF-{\beta}1$ as well as by real time-polymerase chain reaction (PCR). Results: Addition of $anti-TGF-{\beta}1$ monoclonal antibody to cultures of BM-Mp and anti-CD3 mAb-primed syngeneic T cells efficiently induced the proliferation of syngeneic T cells. Conversely, the APC function of B6D cells was almost completely suppressed by addition of $TGF-{\beta}1$. Quantitative real time-PCR analysis also confirmed the enhanced expression of $TGF-{\beta}1$ in BM-Mp. Conclusion: The defective APC function of macrophages generated in vitro with M-CSF and IL-6 was mainly due to the production of $TGF-{\beta}1$ by macrophages.

• Korean Journal of Veterinary Research
• /
• v.36 no.2
• /
• pp.359-369
• /
• 1996

An effective candidate subunit vaccine was prepared by using the immunostimulating complexs(ISCOMs) with Quil A and recombinant protein(gp50, gIII and inactive $\alpha$-ADV) Aujeszky's disease virus(ADV). The weaned pigs were twice immunized with a ADV-ISCOMs, and followed by intramuscular challenge with $1{\times}10^4$ $TCID_{50}$ ADV(strain Yangsan). The unvaccinated pigs were also challenged with same dose of ADV. At 5 days after challenge, the control pigs have developed ADV clinical signs. Whereas, the vaccinated pigs protected them from ADV-induced acute symptoms and death. Also, to identify the lymphocyte subpopulation in peripheral blood with pigs from ADV-ISCOMs vaccinated and control group, lymphocyte reacted with a panel of monoclonal antibodies which are specific to swine leukocyte surface antigens and assayed by the flow cytometry. MHC class I, CD2, CD8, N cells, CD11a, and CD45 antigen positive cells were decreased after inoculating virulent ADV Yangsan strain in control group. The data indicated that ISCOMs technique was useful in ADV subunit vaccine preparation and demonstrated the importance of gp50, gIII as a component of ADV vaccine.

• BMB Reports
• /
• v.34 no.2
• /
• pp.176-181
• /
• 2001

Using a retrovirus, foreign genes can be introduced into mammalian cells. The purpose of this study is to produce a retrovirus that can make the infected cells express two genes; the human multidrug resistance gene (MDR1) and the HLA-B7 gene, which is one of the major human histocompatibility complex (MHC) class I genes. For the expression of these genes, the internal ribosome entry site (IRES) was used, which was derived from the encephalomyocarditis (EMC) virus. In order to produce retroviruses, a retroviral vector was transfected into a packaging cell line and the transfected cells were treated with vincristine, which is an anti-cancer drug and a substrate for the MDRI gene product. This study revealed that two genes were incorporated into chromosomes of selected cells and expressed in the same cells. The production of the retrovirus was confirmed by the reverse transcription (RT)-PCR of the viral RNA. The retrovirus that was produced infected mouse fibroblast cells as well as the human U937. This study showed that packaging cells produced the retroviruses, which can infect the target cells. Once the conditions for the high infectivity of retrovirus into human cells are optimized, thus virus will be used to infect hematopoietic stem cells to co-express MDRl and HLA-B7 genes, and develop the lymphocytes that can be used for the immnogene therapy.