• Archives of Pharmacal Research
• /
• 제20권5호
• /
• pp.396-403
• /
• 1997

In order to direct the form of the immune response in an antigen-specific manner, we constructed a fusion protein (OVA/IL12) that contained the T cell-dependent antigen, ovalbumin (OVA), covalently linked to murine interleukin-12 (IL-12). The OVA/IL12 protein was produced in a baculovirus expression system and was purified by anti-OVA immunoaffinity chromatography. The purified OVA/ILI2 protein displayed potent IL-12 bioactivity in an IL-12 proliferation assay. BALB/c mice immunized with the OVA/IL12 protein produced increased quantities of anti-OVA IgG2a antibody compared with mice immunized with recombinant OVA alone. Lymph node cells from the immunized mice with the OVA/IL12 protein produced large amounts of IFN-,Y when restimulated in vitro with OVA, while those from mice immunized with the OVA protein produced little or no IFN-.gamma.. In contrast, immunization with a mixture of OVA and free recombinant IL-12 also induced IFN-.gamma. production, which was not OVA-specific. These studies indicate that the OVA/IL12 fusion protein can induce OVA-specific, Th1-dominated immune responses, and that the covalent linkage of OVA and IL-12 confines the effect of IL-12 to OVA-specific cells.

• IMMUNE NETWORK
• /
• 제16권5호
• /
• pp.305-310
• /
• 2016

In this study, we compared two different tumor cell vaccines for their induction of anti-tumor immunity; one was a tumor cell clone expressing a membrane-bound form of IL-12 p35 subunit (mbIL-12 p35 tumor clone), and the other was a tumor clone expressing heterodimeric IL-12 as a single chain (mb-scIL-12 tumor clone). The stimulatory effect of mb-scIL-12 on the proliferation of ConA-activated splenocytes was higher than that of mbIL-12 p35 in vitro. However, the stimulatory effect of mbIL-12 p35 was equivalent to that of recombinant soluble IL-12 (3 ng/ml). Interestingly, both tumor clones (mbIL-12 p35 and mb-scIL-12) showed similar tumorigenicity and induction of systemic anti-tumor immunity in vivo, suggesting that tumor cell expression of the membrane-bound p35 subunit is sufficient to induce anti-tumor immunity in our tumor vaccine model.

• IMMUNE NETWORK
• /
• 제13권2호
• /
• pp.63-69
• /
• 2013

IL-12 is a secretory heterodimeric cytokine composed of p35 and p40 subunits. IL-12 p35 and p40 subunits are sometimes produced as monomers or homodimers. IL-12 is also produced as a membrane-bound form in some cases. In this study, we hypothesized that the membrane-bound form of IL-12 subunits may function as a costimulatory signal for selective activation of TAA-specific CTL through direct priming without involving antigen presenting cells and helper T cells. MethA fibrosarcoma cells were transfected with expression vectors of membrane-bound form of IL-12p35 (mbIL-12p35) or IL-12p40 subunit (mbIL-12p40) and were selected under G418-containing medium. The tumor cell clones were analyzed for the expression of mbIL-12p35 or p40 subunit and for their stimulatory effects on macrophages. The responsible T-cell subpopulation for antitumor activity of mbIL-12p35 expressing tumor clone was also analyzed in T cell subset-depleted mice. Expression of transfected membranebound form of IL-12 subunits was stable during more than 3 months of in vitro culture, and the chimeric molecules were not released into culture supernatants. Neither the mbIL-12p35-expressing tumor clones nor mbIL-12p40-expressing tumor clones activated macrophages to secrete TNF-${\alpha}$. Growth of mbIL-12p35-expressing tumor clones was more accelerated in the $CD8^+$ T cell-depleted mice than in $CD4^+$ T cell-depleted or normal mice. These results suggest that $CD8^+$ T cells could be responsible for the rejection of mbIL-12p35-expressing tumor clone, which may bypass activation of antigen presenting cells and $CD4^+$ helper T cells.

• 대한의생명과학회지
• /
• 제26권4호
• /
• pp.344-350
• /
• 2020

Asthma is a chronic disease and occurs in airway in the lung. The cause of the disease has not been identified, it is assumed that both genetic and environmental risk factors play an important role in the development of asthma. Interleukin (IL)-12 is a cytokine regulating T-cell and NK cell. In this study, we analyzed the genetic polymorphisms of IL-12 receptor genes (IL-12Rβ1 and IL-12Rβ2) in asthma patients and normal individuals in a Korean population. We analyzed single nucleotide polymorphisms (SNPs) in IL-12Rβ1 and IL-12Rβ2 using the genotype data of 193 asthma cases and 3,228 healthy controls from the Korea Association REsource for their correlation with asthma case. IL-12Rβ1 and IL-12Rβ2 genes showed statistically significant polymorphism association with asthma case. As a results, 16 SNPs from IL-12Rβ1 and IL-12Rβ2 genes showed statistically significant association with asthma. Among them, rs375947 SNP in IL-12Rβ1 showed the greatest statistical correlation with asthma (P-value = 0.028, Odds Ratio = 1.27, 95% Confidence Interval = 1.03~1.57). The groups with minor allele of IL-12Rβ1 and IL-12Rβ2 showed increased risk of asthma. The genotype-based mRNA expression analysis showed that the group of minor allele of IL-12Rβ1 showed decreased mRNA expression. Decreased IL-12Rβ1 expression causes decreased IL-12 signaling, and this affects developing asthma. In conclusion, the SNPs in IL-12Rβ1 and IL-12Rβ2 may contribute to development of asthma in a Korean population.

• BMB Reports
• /
• 제35권6호
• /
• pp.623-628
• /
• 2002

The Th1 vs. Th2 balance is critical for the maintenance of immune homeostasis. Therefore, the genes that are selectively-regulated by the Th1 and Th2 cytokines are likely to play an important role in the Th1 and Th2 immune responses. In order to search for and identify the novel target genes that are differentially regulated by the Th1/Th2 cytokines, the human PBMC mRNAs differentially expressed upon the stimulation with IL-4 or IL-12, were screened by employing the differential display-polymerase chain reaction. Among a number of clones selected, DC21 was identified as a novel target gene that is regulated by IL-4 and IL-12. The DC21 gene expression was up-regulated either by IL-4 or IL-12, yet counter-regulated by co-treatment with IL-4 and IL-12. DC21 is a dendritic cell protein with an unknown function. The sequence analysis and conserved-domain search revealed that it has two AU-rich motifs in the 3'UTR, which is a target site for the regulation of mRNA stability by cytokines, and that it belongs to the N-acetyltransferase family. The induction of DC21 by IL-12 peaked around 8-12 h, and lasted until 24 h. LY294002 and SB203580 significantly suppressed the IL-12-induced DC21 gene expression, which implies that PI3K and p38/JNK are involved in the IL-12 signal transduction pathway that leads to the DC21 expression. Furthermore, tissue blot data indicated that DC21 is highly expressed in tissues with specialized-resident macrophages, such as the lung, liver, kidney, and placenta. Together, these data suggest a possible role for DC21 in the differentiation and maturation of dendritic cells regulated by IL-4 and IL-12.

• IMMUNE NETWORK
• /
• 제5권1호
• /
• pp.16-22
• /
• 2005

Background: IL-18 was originally cloned as a IFN-${\gamma}$ inducing factor in primed T cells. In synergy with IL-12, IL-18 has been shown to induce strikingly high levels of IFN-${\gamma}$ production by T cells and to enhance Th1 development. Also this cytokine exerts induction of Th2 development through IL-4 induction. Methods: Resting $CD4^+$ T cells were sorted by negative selection and activated by anti-CD3 plus anti-CD28 Ab. Expression of IL-12 binding sites, IL-18 binding sites, IL-18R ${\alpha}$, and GATA-3 mRNA were analysed by FACS and RT-PCR, respectively. Results: Resting $CD4^+$ T cells expressed IL-18R ${\alpha}$ chain but not IL-18 binding sites, suggesting a lack of IL-18R ${\beta}$ expression. IL-18R ${\alpha}$ was maintained on the Th1 and Th2 committed cells. IL-18 binding sites were induced on the Th1 but not Th2 cells. Exposure of these cells to IL-18 led to up-regulation of GATA-3 mRNA expression only in Th2 committed cells. To elucidate the relationship between IL-18R ${\alpha}$ expression and GATA-3 induction by IL-18, Th1 and Th2 committed cells were further cultured in medium with or without IL-12 for 2 days. IL-12 binding sites were maintained on the Th1 and Th2 cells regardless of IL-12 treatment, but IL-18R a expression was rapidly down-regulated on the IL12-untreated Th2 cells which did not induce GATA-3 mRNA expression followed by IL-18 stimulation. Conclusion: IL-12 supports expression of IL-18R ${\alpha}$ and GATA-3 mRNA expression was induced by IL-18 through IL-18R ${\alpha}$ without expression of IL-18 binding site in Th2 cells.

• Archives of Pharmacal Research
• /
• 제28권3호
• /
• pp.274-279
• /
• 2005

Pharmacological inhibition of interleukin-12 (IL-12) production may be a therapeutic strategy for preventing the development and progression of disease in experimental models of autoimmunity. In this study, the effects of myricetin, a naturally occurring flavonoid present in fruits, vegetables and medicinal herbs, on the production of IL-12 were investigated in mouse macrophages stimulated with lipopolysaccharide (LPS). Myricetin significantly inhibited the LPS­induced IL-12 production from both primary macrophages and the RAW264.7 monocytic cell-line in a dose-dependent manner. The effect of myricetin on IL-12 gene promoter activation was analyzed by transfecting RAW264.7 cells with IL-12 gene promoter/luciferase constructs. The repressive effect was mapped to a region in the IL-12 gene promoter containing a binding site for NF-${\kappa}B$. Furthermore, activation of macrophages by LPS resulted in markedly enhanced binding activity to the NF-${\kappa}B$ site, which significantly decreased upon addition of myricetin, indicating that myricetin inhibited IL-12 production in LPS-activated macrophages via the down­regulation of NF-KB binding activity.

• IMMUNE NETWORK
• /
• 제7권4호
• /
• pp.186-196
• /
• 2007

Background: Although IL-12 has been widely accepted to playa central role in the control of pathogen infection, the use of recombinant IL-12 (rIL-12) as a vaccine adjuvant has been known to be ineffective because of its rapid clearance in the body. Methods: To investigate the effect of sustained release of IL-12 in vivo in the peptide and protein vaccination models, rIL-12 was encapsulated into poly ($A_{DL}$-lactic-co-glycolic acid) (PLGA). Results: We found that codelivery of IL-12-encapsulated microspheres (IL-12EM) could dramatically increase not only antibody responses, but also antigen-specific $CD4^+\;and\;CD8^+$ T cell responses. Enhanced immune responses were shown to be correlated with protective immunity against influenza and respiratory syncytial virus (RSV) virus challenge. Interestingly, the enhancement of $CD8^+$ T cell response was not detectable when $CD4^+$ T cell knockout mice were subjected to vaccination, indicating that the enhancement of the $CD8^+$ T cell response by IL-12EM is dependent on $CD4^+$ T cell "help". Conclusion: Thus, IL-12EM could be applied as an adjuvant of protein and peptide vaccines to enhance protective immunity against virus infection.

• Parasites, Hosts and Diseases
• /
• 제51권1호
• /
• pp.85-92
• /
• 2013

IL-23 and IL-12 are structurally similar and critical for the generation of efficient cellular immune responses. Toxoplasma gondii induces a strong cell-mediated immune response. However, little is known about IL-23 secretion profiles in T. gondii-infected immune cells in connection with IL-12. We compared the patterns of IL-23 and IL-12 production by THP-1 human monocytic cells in response to stimulation with live or heat-killed T. gondii tachyzoites, or with equivalent quantities of either T. gondii excretory/secretory proteins (ESP) or soluble tachyzoite antigen (STAg). IL-23 and IL-12 were significantly increased from 6 hr after stimulation with T. gondii antigens, and their secretions were increased with parasite dose-dependent manner. IL-23 concentrations were significantly higher than those of IL-12 at the same multiplicity of infection. IL-23 secretion induced by live parasites was significantly higher than that by heat-killed parasites, ESP, or STAg, whereas IL-12 secretion by live parasite was similar to those of ESP or STAg. However, the lowest levels of both cytokines were at stimulation with heat-killed parasites. These data indicate that IL-23 secretion patterns by stimulation with various kinds of T. gondii antigens at THP-1 monocytic cells are similar to those of IL-12, even though the levels of IL-23 induction were significantly higher than those of IL-12. The detailed kinetics induced by each T. gondii antigen were different from each other.

• 한국식품위생안전성학회지
• /
• 제20권2호
• /
• pp.118-122
• /
• 2005

체내 면역 증강정을 관찰하기 위하여 체내 임파구의 활성 및 증가 여부를 3개월간 의뢰한 물질인 Immu-Forte EX, Immu-Forte 된장고추장, Immu-Forte A, Immu-Forte를 투여한 후, flowcyometry 및 sandwitch ELISA를 이용하여 측정하였다. 본 실험의 실험 기간 중에 동물의 질병이나 감염에 의한 면역학적인 변화가 있었는지를 확인하기 위하여 혈액학적인 검사를 실시하였으며, 혈액학적인 검사에서 Alkaline phosphatase, T protein, Albumin, Creatine, ALT, AST, Total bilirubin, Potasium을 검사해 본 결과 대조군과 비교 했을때 투여군 전군에서 정상적인 범위내 수치를 나타내는 것으로 나타났다. 이러한 결과로부터 본 실험에서 나온 결과는 질병이나 감염에 의한 것이 아닌 생체내에서의 면역성 증강에 의한 것으로 판단할수 있는 근거를 제공한다고 판단되어진다. 한편, 3개월간 장기 투여시 Immu-Forte EX, Immu-Forte 된장고추장, Immu-Forte A과 Immu-Forte 의 모든 물질은 전반적으로 면역 세포와 사이토카인의 수치를 유의적으로 증가시켰다 그러나, 3개월간 Immu-Forte EX를 투여 후 혈중콜레스테롤 수치를 검사해 본 결과 대조군$(118\pm24.4 mg/dL)$과 비교하였을때, 고용량$(126\pm7.7 mg/dL)$, 중간용량$(121\pm8.4 mg/dL)$, 저용량$(109\pm24.Smg/dL)$으로서 통계학적인 유의적 감소로는 보이지 않는다. 각각의 물질의 면역학적인 변화양상을 살펴보면 물질 동암 EX는 중간 농도군에서는 CD4 T 림파구, CD8 림파구, 대식세포, IL-12, IFN-r가 대조군에 비해서 유의적으로 증가했으며 떠농도에서는 전체 T 임파구, 전체 B 임파구, CD4 T 임파구, 대식세포, IL-2, IL4, IL-12가 대조군에 비해서 유의적으로 증가했다. 물질 Immu-Forte 된장고추장에서는 고농도에서는 CD4 T 임파구, IL-2, IL-4, IL-12가 유의적으로 증가했으며, 중간농도에서는 CD4 임파구, 대식세포, IL-2,IL-4,IL-12 가 유의적으로 증가했고, 저농도에서는 전체 T 임파구, CD4 T 임파구, IL-2, IL-4, IL-12가 유의적으로 증가했다. 물질 Immu-Forte A의 경우 고농도에서 대식세포,자연살해세포, IL-12가 중간농도에서는 전체 T임파구, CD4 T임파구, 대식세포, 자연살해세포, IL-2, IL-4, IL-12가 저농도에서는 자연살해세포가 유의적으로 증가했다. 물질 Immune-Forte f의 경우 고농도에서 전체 B 임파구, IL-4, IL-12가 중간농도에서 전체 T임파구, 전체 B임파구, CD4 T임파구, CD8 T 임파구, 대식세포, IL-2, IL-4, IL-12, IFN-r가 저농도에서는 자연살해세포, IL-12가 유의적으로 증가하였다. 이상과 같이 각각의 물질은 전반적으로 면역증강 효과가 있는 것으로 나타났으며 그 면역증강을 유도하는 세포나 사이토카인은 서로 정확히 일치하지 않는 것으로 보아 각각의 물질이 다른 기전을 통해서 면역증강을 유도하는 것으로 생각된다.