Browsing by Author "Chang, Hua-Chen"
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Item Acquired STAT4 deficiency as a consequence of cancer chemotherapy(2011-08-16) Lupov, Ivan; Chang, Hua-Chen; Randall, Stephen Karl, 1953-; Robertson, Michael J.Signal Transducer and Activator of Transcription 4 (STAT4) is an important transcription factor activated by IL-12 signaling. Activated STAT4 is essential for Th1 cell differentiation, a process characterized by increased potential for interferon (IFN)-γ production. Defective IFN-γ production due to STAT4 deficiency occurs after autologous stem cell transplantation for lymphoma. We have investigated the mechanisms of post-transplant STAT4 deficiency. The tumor-bearing state is ruled out to be the cause because STAT4 levels were not significantly different in peripheral blood mononuclear cells (PBMCs) obtained from lymphoma patients prior to treatment and healthy control subjects. The magnitude of the decrease in STAT4 levels corresponded with increasing intensity of chemotherapeutic treatment in vivo. Furthermore, treatment of normal PBMC cultures or a natural killer (NK) cell line with chemotherapy drugs in vitro also resulted in reduced STAT4 protein and reduced IL-12-induced IFN-γ production. Chemotherapy drugs are shown to have no impact on the stability of STAT4 mRNA, while steady-state levels of STAT4 transcripts are decreased in lymphoma patients. Our findings demonstrated that chemotherapeutic drugs up-regulate the ubiquitination rates of the STAT4 protein, which in turn promotes its degradation via the proteasome-mediated pathway. Treatment with the proteasome inhibitor bortezomib largely reversed the chemotherapy-induced STAT4 deficiency. Thus, acquired STAT4 deficiency in lymphoma patients is a consequence of treatment with chemotherapy. These results have important implications for design of optimal immunotherapy for lymphoma.Item Activation of Dendritic Cell Function by Soypeptide Lunasin as a Novel Vaccine Adjuvant(Office of the Vice Chancellor for Research, 2015-04-17) Simmons, Sharena J.; Tung, Chun-Yu; Chang, Hua-ChenThe innate immune system is the first line of defense against intruding pathogens. Dendritic cells (DCs) act as messengers between the adaptive and innate immune system, which process and present antigens to mature T helper cells (CD4+T), and Cytotoxic T cells (CD8+T). The addition of an appropriate adjuvant that activates the innate immunity is essential to subsequent development of the adaptive immunity specific to the vaccine antigens. Thus, any innovation capable of improving the immune responses may lead to a more efficacious vaccine. We recently identified a novel immune modulator using a naturally occurring seed peptide called lunasin. Lunasin was originally isolated from soybeans, and it is a small peptide containing 43 amino acids. Our studies had revealed stimulatory effects of lunasin on innate immune cells by regulating expression of a number of genes that are important for immune responses. The objective was to define the effectiveness of lunasin as an adjuvant that enhances immune responses. Immunization of mice with ovalbumin (OVA) and lunasin inhibited the growth of OVA-expressing A20 B-lymphomas, which was correlated with OVA-specific CD8+ T cells. Increased levels of anti-OVA IgG were also observed in mice immunized with OVA and lunasin. These results suggest that lunasin may function as a vaccine adjuvant by promoting DC maturation, which in turn enhances the development of protective immune responses to the vaccine antigens.Item Activation of Dendritic Cells by Soypeptide Lunasin: Implication in Vaccine Adjuvant(Office of the Vice Chancellor for Research, 2014-04-11) Flores, Sarah; Dong, Melissa; Tung, Chun-Yu; Chang, Hua-ChenAdjuvants enhance the immunogenicity of vaccines and improve the immune responses. Although many adjuvants are currently used in research, FDA approved aluminum salt (Alum) remains the most often used in human vaccines. Alum is known to promote the Th2 immune response and enhance antibody production, but is less efficient on eliciting Th1 and CTL cellular responses. Thus, it is prudent to improve the effectiveness of current adjuvants or to develop a novel alternative adjuvant. We have recently identified lunasin, a seed peptide from soybeans, as a novel immune modulator. The objective is to define the effectiveness of lunasin peptide as an adjuvant that can enhance the protective immunity of vaccines. Our studies have revealed stimulatory effects of lunasin on dendritic cells (DCs) by regulating expression of a number of genes that are important for immune responses. Lunasin-treated human conventional DCs (cDCs) not only expressed elevated levels of co-stimulatory molecules (CD86) but also exhibited up-regulation of chemokines (CCL2, CCL3, CCL4) and cytokine (IL-1β). To determine the function of lunasin-treated cDCs, these cells were co-cultured with allogeneic human peripheral blood CD4+ T cells for 7 days in the mixed lymphocyte reaction. Lunasin-treated cDCs induced almost 2-fold higher proliferation of allogeneic CD4+ T cells when comparing with a sham treatment. To verify the in vivo effects, lunasin was administered into mice. Increased CD86 expression was found in cDCs from spleens of mice treated with lunasin. Furthermore, mice vaccinated with lunasin-adjuvanted ovalbumin (OVA) had reduced tumor growth following challenging with OVA-expressing A20 B-lymphoma cells. Taken together, our data suggest that lunasin may act as a vaccine adjuvant by targeting DCs to enhance and modulate the immune responses to antigens.Item Activation of Natural Killer Cell by Lunasin and Cytokine(Office of the Vice Chancellor for Research, 2014-04-11) Kyazike, Sharifah; Lewis, David; Tung, Chun-Yu; Han, Ling; Chang, Hua-ChenCancer immunotherapy is one of the emerging therapeutic strategies to harness the immune system to eradicate chemotherapy-resistant cancerous cells. NK cells can recognize and eliminate cancer cells before adaptive immunity is developed. Human NK cells can be divided into 2 major subsets based on their surface expression of CD56. NK cells with CD56 bright populations are major cytokine producers, while NK cells expressing CD56 dim have higher lytic activity. Due to the role of NK cells in cancer surveillance, any approach to enhance their activity may augment cancer treatment. We have recently shown that soypeptide Lunasin is a novel immune modulating agent that, together with cytokines, enhances IFN- γ and Granzyme B expression by NK cells. This synergism augments the natural cytotoxicity of NK cells against various tumors in vitro as well as in the xenograft model. The objective of this study is to evaluate the effects of Lunasin on antibody-dependent cellular cytotoxicity (ADCC) activity of NK cells against Rituximab-coated human B-lymphoma Raji cells. We also evaluated the expression of several markers involved in NK-mediated tumorcidal activity using flow cytometry. Together, these results suggest that Lunasin could enhance the efficacy of NK cell-based immunotherapy for cancer.Item Analysis of differentiation capacity of Cfp1 null embyronic stem cells(2014) Bowen, Tamara R.; Skalnik, David Gordon; Marrs, James; Chang, Hua-ChenEpigenetics is defined as “the study of stable, often heritable, changes that influence gene expression that are not mediated by DNA sequence” (Fingerman et al., 2013). Epigenetic marks such as covalent histone modifications and DNA methylation are important for maintaining chromatin structure and epigenetic inheritance. Several proteins have been found to bind and/ or regulate epigenetic marks. One such protein, CXXC finger protein 1 (Cfp1) is an important chromatin regulator that binds to unmethylated CpG islands. It has been found to be essential for mammalian development. Mice lacking Cfp1 exhibit an embryonic- lethal phenotype. However, the function of Cfp1 can be studied using Cfp1 Null mouse ES cells, which are viable. Thus far, Cfp1 has been shown to be important for cell growth, cytosine methylation, histone modifications, subnuclear localization of Set1A histone H3K4 methyltransferase, and cellular differentiation. When Cfp1 Null ES cells are induced to differentiate by removal of Leukemia Inhibitory Factor (LIF), the cells are not able to turn off pluripotency markers such as Oct4 and alkaline phosphatase and fail to express differentiation markers such as Gata4 and Brachyury. In this study, we used established protocols to further examine the differentiation capacity of Cfp1 Null cells. Specifically, we tested the ability of Cfp1 Null ES cells to retain stem cell properties in the absence of LIF, differentiate into cardiomyocytes in the presence of TGF-β2 and differentiate into neuron precursors in the presence of retinoic acid (RA). While the differentiation effects of RA were inconclusive, Null cells were able to start differentiating in the absence of LIF, either as individual cells or EBs, and the presence of TGF-β2 when seeded on gelatin coated tissue culture dishes. However, no difference was seen between cells treated without LIF and those treated with TGF-β2. In both conditions, only a small portion of cells were able to differentiate, while the majority of the cell population retained stem cell characteristics. Cell growth and the differentiation capacity of Cfp1 Null cells were also compromised in comparison to WT cells. Thus, further supporting the need for the correct epigenetic patterns maintained by Cfp1 during cellular differentiation.Item Effects of Soy Peptide on Dendritic Cells(Office of the Vice Chancellor for Research, 2013-04-05) Shipman, Kaylee; Tung, Chun-Yu; Han, Ling; Patel, Amy; Corn, Caleb; Chang, Hua-ChenInnate immunity is mediated by effector cells, including NK cells, dendritic cells (DCs), macrophages, and polymorphonuclear phagocytes, which can respond immediately after activation through receptors encoded by germ-line genes. Innate immune responses represent the first line of defense in immunosurveillance. Interventions that enhance the functions of innate immunity will be an important armamentarium to human health. We recently exploited a natural dietary soy peptide called lunasin to improve the immune functions. The hypothesis was that lunasin peptide has stimulatory effects on immune cells. To test this hypothesis, human peripheral blood mononuclear cells (PBMCs) of healthy donors were stimulated with or without lunasin. We found that lunasin is capable of stimulating DCs to up-regulate chemokines (CCL2, CCL3, and CCL4), cytokines (TNFα and IFNα), and co-stimulatory molecules (CD80, CD86). In addition, lunasin-treated DCs can provide NK with required signals for activation. Taken together, our results support the immunomodulatory activity of soy peptide on DCs, which leads to enhancement of innate immunity.Item EFFECTS OF TYPE VI COLLAGEN ON MACROPHAGES(Office of the Vice Chancellor for Research, 2011-04-08) Voiles, Larry; Han, Ling; Lupov, Ivan P.; Anderson, Bailey; Melnikov, Lonya; Pottratz, Sarah Marie; Chang, Hua-ChenEmphysema is an abnormal inflammatory response of the alveoli that lose their elasticity due to destruction of alveolar septi. Collagen, an extracellular matrix protein (ECM), is expressed in the lung, which is important in maintaining the integrity of the tissue. Destruction of the ECM components in the alveolar structure contributes to the development of emphysema. We have found that the gene expression of type VI collagen (COL6A1) is higher in the lungs of emphysema patients as compared to that from normal controls. Type VI collagen (COL6) is found in the pulmonary interstitial compartment where massive macrophages are infiltrated in the inflammatory environment. The hypothesis is that excessive COL6 activates macrophages to mediate inflammatory responses, which may contribute to the pathogenesis of emphysema. The goal is to define the effects of type VI collagen on macrophages. Results from murine bone marrow derived macrophages showed a marked increase in the numbers of CD86-positive cells after soluble COL6 stimulation. To further support the stimulatory function of COL6, human THP-1 cells as well as primary monocytes produced inflammatory cytokines IL-12 and IFNγ following COL6 stimulation. Taken together, our data has demonstrated the stimulatory effects on macrophages by COL6 stimulation, which may mediate the inflammatory responses in the pathogenesis of emphysema.Item Enhancement of Cancer Immunotherapy Using Immune Modulating Peptides(Office of the Vice Chancellor for Research, 2013-04-05) Chang, Hua-Chen; Han, Ling; Lewis, David; Tung, Chun-Yu; Srinivasan, Mythily; Robertson, Michael J.; Yeh, Wu-KuangImmune Peptide Therapeutics (IPT) LLC, an Indiana-based small business and its research partner Indiana University previously identified a novel property of lunasin as a distinct class of immune modulating agent that enhances anti-tumor immunity, which may promote disease-free survival by limiting tumor progression, and thus prolong lives of cancer patients. Lunasin, a synthetic 43-amino acid peptide, was originally isolated from soybeans. Our studies have demonstrated that lunasin exerts robust synergistic effects with cytokines on augmenting IFNγ and granzyme B expression by Natural Killer (NK) cells, which is associated with increased tumoricidal activity of NK cells. In addition, this combination regimen is capable of rescuing IFNγ production ex vivo by NK cells from chemotherapy-treated Non-Hodgkin’s Lymphoma (NHL) patients who are immunocompromised with acquired immune deficiency. The long-term goal is to develop an efficacious immunotherapy which will impact the treatment and improve the clinical outcomes for NHL patients. The dose-response study indicates the optimum concentration of lunasin is at the range of μM, which would undermine its use in clinical studies. To enhance the medicinal value lunasin must be optimized for in vitro and in vivo efficacy. The objective is to develop a second generation of lunasin, which will increase its potency to improve the performance. In this study we have implemented several strategies to design and modify the prototype. The newly developed peptide called IPT.103 has 15 amino acids that are in the D-isoform configuration. Activity of IPT.103 has been tested in vitro with EC50 of 0.78 μM as compared to 4.54 μM for lunasin. IPT.103 also has in vivo activity on enhancing the serum levels of IFNγ production using a mouse model. Taken together, we have developed a peptide derivative (IPT.103) that deviates from its parental type lunasin to increase intellectual merit for commercialization as well as support clinical application.Item ENHANCING THE TUMOR FIGHTING CAPACITY OF NK CELLS THROUGH THE USE OF SOYPEPTIDE(Office of the Vice Chancellor for Research, 2012-04-13) Lewis, David; Chang, Hua-Chen; Han, Ling; Voiles, Larry; Henriquez, Sarah M.P.Natural killer or (NK) cells are important components of the innate immune system, which play a major role in the rejection of tumors, and virally in-fected cells. By producing pro-inflammatory cytokines such as IFN-gamma, NK cells are able to exert immunoregulatory functions that influence the adaptive immunity of other immune cells. Due to its critical role in tumor inhibition, researchers, utilizing various cytokines, including IL-12 and IL-2, have fervently pursued the manipulation of NK activity. NK cells respond to cytokines in a dose-dependent manner; however, the toxicity of certain cy-tokines (like IL-2) in high doses prohibits their widespread clinical use. Therefore, efforts to activate NK cells without requiring high doses of cyto-kines is warranted. We recently exploited a soy derived dietary peptide called lunasin to improve the immune functions. The hypothesis was that the lunasin peptide has stimulatory effects on immune cells. To test this hy-pothesis, human peripheral blood mononuclear cells (PBMCs) of healthy do-nors were stimulated with and without lunasin in combination with cytokines IL-12 or IL-2. Our results showed that the lunasin peptide exerts a robust synergistic effect when combined with the selected cytokines. This effect ap-pears to regulate the expression of a number of genes that are important for NK activity. Our findings support the potential clinical use of lunasin in com-bination with cytokine to enhance the tumor fighting capacity of NK cells.Item Lunasin alleviates allergic airway inflammation while increases antigen-specific Tregs(PLoS, 2015-02-03) Yang, Xiaowei; Zhu, Jingjing; Tung, Chun-Yu; Gardiner, Gail; Wang, Qun; Chang, Hua-Chen; Zhou, Baohua; Department of Pediatrics, IU School of MedicineLunasin is a naturally occurring peptide isolated from soybeans and has been explored in cancer treatment. Lunasin inhibits NF-κB activation and thus pro-inflammatory cytokine and mediator production in macrophages. In this study we demonstrate that lunasin can effectively suppress allergic airway inflammation in two murine models of asthma. In an OVA+Alum sensitization model, intranasal lunasin treatment at the time of OVA challenges significantly reduced total cells counts in bronchoalveolar lavage (BAL) fluid and eosinophilia, peribronchiolar inflammatory infiltration, goblet cell metaplasia and airway IL-4 production. In an OVA+LPS intranasal sensitization model, lunasin treatment either at the time of sensitization or challenge has similar effects in suppress allergic airway inflammation including significantly reduced total cell and eosinophil counts in BAL fluid, inflammatory gene Fizz1 expression in the lung, and IL-4 production by OVA re-stimulated cells from mediastinal lymph nodes. We further show that intranasal instillation of OVA+lunasin significantly increases OVA-specific regulatory T cell (Treg) accumulation in the lung comparing to OVA only treatment. Taken together, our results suggest lunasin as an anti-inflammatory agent can be potentially used in asthma therapy or as an adjuvant to enhance the induction of antigen-specific Tregs and thus boost the efficacy of allergy immunotherapy.