1
|
Fallah MP, Chelvarajan RL, Bondada S. THE Class IA PI3-Kinase signaling Pathway: A Potential Target for Enhancing the Proinflammatory Cytokines in the Aged Macrophages (135.53). The Journal of Immunology 2009. [DOI: 10.4049/jimmunol.182.supp.135.53] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
The elderly suffer from increased infections with Streptococcus pneumonia due to a reduced ability to produce antibodies to the capsular polysaccharide (CPS) antigens. The antibody response to CPS is T-independent but needs the macrophage-derived cytokines such as IL-12, IL-6 and IL-1beta to induce anti-CPS antibody response. We found that production of these cytokines via TLR4 or TLR2 stimulation is dysregulated in both splenic (SM) and bone marrow derived macrophages (BMDM) from the aged (20-24 months) in comparison to young adult (8-12 weeks) BALB/c mice: a decrease in IL-12, IL-6 and IL-1beta but an increase in IL-10 in the aged. We hypothesized that the aged macrophages have an intrinsic signaling defect leading to cytokine dysregulation. A microarray analysis showed that aged SM expresses more P110delta and p85beta subunits of Class IA PI3-Kinase than the young adult. This was confirmed, at the mRNA levels, via qt-RTPCR in both SM and BMDM and at the protein levels for P-AKT (a downstream target of PI3-kinase) in BMDM. Inhibition of the PI3-kinase with LY294002, shifted the TLR2/4 induced cytokine phenotype of the aged to that of the young adult. Therefore, targeting PI3-Kinase could rescue the intrinsic signaling defect in the aged macrophages and enhance anti-CPS antibody responses.
Collapse
Affiliation(s)
| | - Ralph L Chelvarajan
- 2Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, Kentucky
| | - Subarrao Bondada
- 3Microbiology, Immunology and Molecular Genetics, University of kentucky, Lexington, KY
- 4Markey Cancer Center, University of kentucky, Lexington, KY
| |
Collapse
|
2
|
Ke J, Gururajan M, Kumar A, Simmons A, Turcios L, Chelvarajan RL, Cohen DM, Wiest DL, Monroe JG, Bondada S. The role of MAPKs in B cell receptor-induced down-regulation of Egr-1 in immature B lymphoma cells. J Biol Chem 2006; 281:39806-18. [PMID: 17065146 DOI: 10.1074/jbc.m604671200] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cross-linking of the B cell receptor (BCR) on the immature B lymphoma cell line BKS-2 induces growth inhibition and apoptosis accompanied by rapid down-regulation of the immediate-early gene egr-1. In these lymphoma cells, egr-1 is expressed constitutively and has a prosurvival role, as Egr-1-specific antisense oligonucleotides or expression of a dominant-negative inhibitor of Egr-1 also prevented the growth of BKS-2 cells. Moreover, enhancement of Egr-1 protein with phorbol 12-myristate 13-acetate or an egr-1 expression vector rescued BKS-2 cells from BCR signal-induced growth inhibition. Nuclear run-on and mRNA stability assays indicated that BCR-derived signals act at the transcriptional level to reduce egr-1 expression. Inhibitors of ERK and JNK (but not of p38 MAPK) reduced egr-1 expression at the protein level. Transcriptional regulation appears to have a role because egr-1 promoter-driven luciferase expression was reduced by ERK and JNK inhibitors. Promoter truncation experiments suggested that several serum response elements are required for MAPK-mediated egr-1 expression. Our study suggests that BCR signals reduce egr-1 expression by inhibiting activation of ERK and JNK. Unlike ERK and JNK, p38 MAPK reduces constitutive expression of egr-1. Unlike the immature B lymphoma cells, normal immature B cells did not exhibit constitutive MAPK activation. BCR-induced MAPK activation was modest and transient with a small increase in egr-1 expression in normal immature B cells consistent with their inability to proliferate in response to BCR cross-linking.
Collapse
Affiliation(s)
- Jiyuan Ke
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, Kentucky 40536, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
3
|
Chelvarajan RL, Collins SM, Doubinskaia IE, Goes S, Van Willigen J, Flanagan D, De Villiers WJS, Bryson JS, Bondada S. Defective macrophage function in neonates and its impact on unresponsiveness of neonates to polysaccharide antigens. J Leukoc Biol 2004; 75:982-94. [PMID: 14982942 DOI: 10.1189/jlb.0403179] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Neonates do not respond to thymus-independent (TI) antigens (Ag), making them vulnerable to infection with encapsulated bacteria. The antibody (Ab) response of adult and neonatal B cells to TI Ag requires certain cytokines, which are provided by T cells or macrophages (MPhi). Lipopolysaccharide (LPS) failed to induce neonatal MPhi to produce interleukin (IL)-1beta and tumor necrosis factor alpha (TNF-alpha) mRNA and to secrete IL-1beta, IL-12, and TNF-alpha. However, LPS induced neonates to secrete some IL-6 and three- to fivefold more IL-10 than adults. Accordingly, adding adult but not neonatal MPhi could restore the response of purified adult B cells to trinitrophenol (TNP)-LPS, a TI Ag. Increased IL-10 is causally related to decreased IL-1beta and IL-6 production, as IL-10(-/-) neonatal MPhi responded to LPS by secreting more IL-1beta and IL-6 than wild-type (WT) neonatal MPhi. When cultures were supplemented with a neutralizing Ab to IL-10, WT neonatal MPhi secreted increased amounts of IL-6 and allowed neonatal MPhi to promote adult B cells to mount an Ab response against TNP-LPS. Thus, neonates do not respond to TI Ag as a result of the inability of neonatal MPhi to secrete cytokines, such as IL-1beta and IL-6, probably as a result of an excess production of IL-10. This dysregulated cytokine secretion by neonatal MPhi may be a result of a reduction in expression of Toll-like receptor-2 (TLR-2) and TLR-4 and CD14.
Collapse
|
4
|
Affiliation(s)
| | - Amy Troyer
- University of Kentucky Lexington Kentucky
| | | |
Collapse
|
5
|
Abstract
T independent antigens elicit antibody responses in the absence of carrier specific T helper cells but require signals from accessory cells (macrophages and dendritic cells) or specific cytokines. They are further subdivided into TI-1 and TI-2 categories based on the ability of TI-1 but not TI-2 antigens to elicit immune responses from neonates. Most bacterial polysaccharides including the pneumococcal polysaccharide vaccines belong to the TI-2 class. It is hypothesized that defects in accessory cell function play a critical role in the failure of neonates to respond to such TI-2 antigens. Immune responses to these TI-2 stimuli are also reduced in the aged, also due to a quantitative deficiency in accessory cells. Agents that can stimulate accessory cell function may provide an alternative strategy to improve the immunogenicity of the polysaccharide vaccines in the neonates and the aged.
Collapse
Affiliation(s)
- S Bondada
- Department of Microbiology and Immunology, Sanders Brown Center on Aging, School of Medicine, University of Kentucky, Room 329, Sanders-Brown Building, 40536-0230, Lexington, KY, USA.
| | | | | | | |
Collapse
|
6
|
Chelvarajan RL, Raithatha R, Venkataraman C, Kaul R, Han SS, Robertson DA, Bondada S. CpG oligodeoxynucleotides overcome the unresponsiveness of neonatal B cells to stimulation with the thymus-independent stimuli anti-IgM and TNP-Ficoll. Eur J Immunol 1999; 29:2808-18. [PMID: 10508255 DOI: 10.1002/(sici)1521-4141(199909)29:09<2808::aid-immu2808>3.0.co;2-e] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Neonates are very vulnerable to pathogenic encapsulated bacteria due to their inability to mount an antibody response to capsular polysaccharides, which are thymus-independent type 2 (TI-2) antigens (Ag). Oligodeoxynucleotides (ODN) containing unmethylated CpG dinucleotides induced neonatal B cells to proliferate to anti-IgM, a TI-2 stimulus. CpG ODN inhibited the spontaneous and B cell receptor-mediated apoptosis of neonatal B cells and reduced the amount of the pro-apoptotic Bcl-xS, strongly correlated with anti-IgM-induced apoptosis of neonatal B cells. CpG ODN protected neonatal B cells from apoptosis by down-regulation of the Bcl-xS protein. Neonatal B cells underwent polyclonal differentiation upon stimulation with CpG ODN, but unlike in adult B cells, this was not preceded by IL-6 secretion. CpG ODN stimulated neonatal B cells to mount an Ag-specific antibody response to TNP-Ficoll, another TI-2 Ag. Thus CpG ODN could provide a novel approach to induce the immune system in neonates to respond to harmful encapsulated bacteria.
Collapse
Affiliation(s)
- R L Chelvarajan
- Department of Microbiology and Immunology and Sanders-Brown Research Center on Aging, University of Kentucky, Lexington, KY 40536-0230, USA
| | | | | | | | | | | | | |
Collapse
|
7
|
Han SS, Chung ST, Robertson DA, Chelvarajan RL, Bondada S. CpG oligodeoxynucleotides rescue BKS-2 immature B cell lymphoma from anti-IgM-mediated growth inhibition by up-regulation of egr-1. Int Immunol 1999; 11:871-9. [PMID: 10360960 DOI: 10.1093/intimm/11.6.871] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Cross-linking of the IgM antigen receptor on an immature B cell lymphoma (BKS-2) induces growth arrest and apoptosis. This is accompanied by down-regulation of the immediate early genes, egr-1 and c-myc, and a reduction in NF-kappaB activity. Anti-IgM-induced growth arrest and apoptosis of this murine B cell lymphoma were prevented by oligodeoxynucleotides (ODN) containing the CpG motif, which are also known to be stimulatory for mature and immature B cells. The CpG but not non-CpG ODN rescued BKS-2 cells from anti-IgM-mediated growth inhibition by up-regulation of egr-1 and c-myc expression as well as by restoring NF-kappaB activity. Interestingly, changes in egr-1 expression occurred more rapidly than in c-myc expression. Also the c-myc levels remained high up to 6 h after addition of the anti-IgM, which was also the time until which the addition of CpG could be delayed without affecting its ability to provide complete protection. This CpG-induced rescue of B lymphoma cells was blocked by antisense egr-1 ODN, suggesting that the expression of egr-1 is important for the effects of CpG ODN on the growth and survival of BKS-2 cells.
Collapse
MESH Headings
- Animals
- Antibodies, Anti-Idiotypic/physiology
- Apoptosis/immunology
- CpG Islands
- DNA-Binding Proteins/biosynthesis
- DNA-Binding Proteins/genetics
- Dose-Response Relationship, Immunologic
- Early Growth Response Protein 1
- Gene Expression Regulation, Neoplastic/immunology
- Genes, myc
- Growth Inhibitors/physiology
- Immediate-Early Proteins
- Immunoglobulin M/immunology
- Lymphoma, B-Cell/genetics
- Lymphoma, B-Cell/immunology
- Lymphoma, B-Cell/metabolism
- Mice
- Mice, Inbred CBA
- Mice, SCID
- NF-kappa B/metabolism
- Oligonucleotides, Antisense/pharmacology
- Proto-Oncogene Proteins c-myc/biosynthesis
- Proto-Oncogene Proteins c-myc/genetics
- Transcription Factors/biosynthesis
- Transcription Factors/genetics
- Tumor Cells, Cultured
- Up-Regulation/immunology
Collapse
Affiliation(s)
- S S Han
- Department of Microbiology and Immunology, and Sanders-Brown Research Center on Aging, University of Kentucky, Lexington, KY 40536, USA
| | | | | | | | | |
Collapse
|
8
|
Venkataraman C, Chelvarajan RL, Cambier JC, Bondada S. Interleukin-4 overcomes the negative influence of cyclic AMP accumulation on antigen receptor stimulated B lymphocytes. Mol Immunol 1998; 35:997-1014. [PMID: 9881695 DOI: 10.1016/s0161-5890(98)00068-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Activation of protein kinase A (PKA) in B lymphocytes prior to the ligation of the B cell antigen receptor (BCR) results in a profound inhibition of BCR induced proliferation. The major effect of increased PKA activity in B lymphocytes was the induction of apoptosis leading to a reduced BCR induced growth response. The growth promoting cytokine IL-4 rescued B lymphocytes from PKA mediated negative effects. IL-4 protected BCR stimulated cells from PKA mediated inhibition primarily by preventing apoptosis and growth arrest. PKA-activation caused a downregulation of anti-IgM induced expression of Bcl-xL protein, that was restored by IL-4. Previous studies have shown that PKA-activation blocks BCR induced phospholipase Cgamma-activation and calcium mobilization. IL-4 was unable to overcome the block in anti-IgM mediated calcium mobilization due to PKA-activation. B cell apoptosis induced by PKA-activation was also seen in CD72 stimulated cells, although CD72 mediated B-lymphocyte proliferation was not affected. PKA mediated block in phospholipase gamma-activation and calcium mobilization were not due to alterations in the activation of tyrosine kinases lyn, blk and syk. Moreover, BCR mediated tyrosine phosphorylation of PLC gamma2 and CD19 were also unaffected by cAMP accumulation. These observations are in contrast to the ability of PKA to drastically reduce the activity of ZAP-70 and syk in T lymphocytes and neutrophils, respectively. The IL-4 mediated protection appears to be due to a change in late events in BCR signaling, which are important for Bcl-xL expression.
Collapse
MESH Headings
- Animals
- Antibodies, Anti-Idiotypic/pharmacology
- Antigens, CD19/metabolism
- Apoptosis/drug effects
- Apoptosis/physiology
- B-Lymphocytes/drug effects
- B-Lymphocytes/immunology
- B-Lymphocytes/metabolism
- Calcium/metabolism
- Cyclic AMP/metabolism
- Cyclic AMP/pharmacology
- Down-Regulation/drug effects
- Enzyme Activation
- Female
- Growth/drug effects
- Interleukin-4/pharmacology
- Isoenzymes/metabolism
- Lymphocyte Activation/drug effects
- Mice
- Mice, Inbred BALB C
- Mice, Inbred DBA
- Phospholipase C gamma
- Phosphorylation
- Protein-Tyrosine Kinases/metabolism
- Proteins/chemistry
- Proto-Oncogene Proteins c-bcl-2/biosynthesis
- Proto-Oncogene Proteins c-bcl-2/drug effects
- Receptors, Antigen, B-Cell/antagonists & inhibitors
- Receptors, Antigen, B-Cell/immunology
- Receptors, Antigen, B-Cell/physiology
- Signal Transduction/drug effects
- Type C Phospholipases/metabolism
- Tyrosine/metabolism
- bcl-X Protein
Collapse
Affiliation(s)
- C Venkataraman
- Department of Microbiology and Immunology and Sanders-Brown Center on Aging, University of Kentucky, Lexington 40536, USA
| | | | | | | |
Collapse
|
9
|
Chelvarajan RL, Gilbert NL, Bondada S. Neonatal Murine B Lymphocytes Respond to Polysaccharide Antigens in the Presence of IL-1 and IL-6. The Journal of Immunology 1998. [DOI: 10.4049/jimmunol.161.7.3315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Abstract
Unlike adults, neonates are unable to respond to polysaccharide Ags, making them especially vulnerable to pathogenic encapsulated bacteria. Since the Ab response to polysaccharides in adult mice requires certain cytokines, it was hypothesized that neonatal murine B cells may be competent to respond to such Ags, but may fail to do so due to a deficiency of cytokines. Neonatal splenocyte cultures, which were otherwise unresponsive to trinitrophenyl (TNP)-Ficoll, a haptenated polysaccharide Ag, mounted an adult-like Ab response when supplemented with IL-1. However, IL-1 failed to induce such a response to TNP-Ficoll when purified B cells were used instead. Although IL-6 alone did not induce a response in whole spleen cells or purified B cells from neonates, it synergized with IL-1 in inducing purified neonatal B cells to respond to TNP-Ficoll. The avidity of the cytokine-induced neonatal anti-TNP Abs was comparable to that of Abs made by adult splenocyte cultures. One effect of IL-1 may be at the level of clonal expansion, since it induced neonatal B cells to proliferate in response to anti-IgM, which was further enhanced by IL-6. The spontaneous secretion of IL-1 by neonatal splenocytes was below the detection limit, while adult splenocytes secreted 30.8 ± 5.2 U/ml, which is of the same order of magnitude as what was required to stimulate neonatal B cells to respond to TNP-Ficoll. Thus, the neonatal unresponsiveness to polysaccharide Ags could be due to the inability of a non-B cell population resident in the neonatal spleen to secrete sufficient quantities of IL-1.
Collapse
Affiliation(s)
- Ralph L. Chelvarajan
- Department of Microbiology and Immunology and Sanders-Brown Research Center on Aging, University of Kentucky, Lexington, KY 40536
| | - Nikole L. Gilbert
- Department of Microbiology and Immunology and Sanders-Brown Research Center on Aging, University of Kentucky, Lexington, KY 40536
| | - Subbarao Bondada
- Department of Microbiology and Immunology and Sanders-Brown Research Center on Aging, University of Kentucky, Lexington, KY 40536
| |
Collapse
|
10
|
Chelvarajan RL, Gilbert NL, Bondada S. Neonatal murine B lymphocytes respond to polysaccharide antigens in the presence of IL-1 and IL-6. J Immunol 1998; 161:3315-24. [PMID: 9759847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Unlike adults, neonates are unable to respond to polysaccharide Ags, making them especially vulnerable to pathogenic encapsulated bacteria. Since the Ab response to polysaccharides in adult mice requires certain cytokines, it was hypothesized that neonatal murine B cells may be competent to respond to such Ags, but may fail to do so due to a deficiency of cytokines. Neonatal splenocyte cultures, which were otherwise unresponsive to trinitrophenyl (TNP)-Ficoll, a haptenated polysaccharide Ag, mounted an adult-like Ab response when supplemented with IL-1. However, IL-1 failed to induce such a response to TNP-Ficoll when purified B cells were used instead. Although IL-6 alone did not induce a response in whole spleen cells or purified B cells from neonates, it synergized with IL-1 in inducing purified neonatal B cells to respond to TNP-Ficoll. The avidity of the cytokine-induced neonatal anti-TNP Abs was comparable to that of Abs made by adult splenocyte cultures. One effect of IL-1 may be at the level of clonal expansion, since it induced neonatal B cells to proliferate in response to anti-IgM, which was further enhanced by IL-6. The spontaneous secretion of IL-1 by neonatal splenocytes was below the detection limit, while adult splenocytes secreted 30.8 +/- 5.2 U/ml, which is of the same order of magnitude as what was required to stimulate neonatal B cells to respond to TNP-Ficoll. Thus, the neonatal unresponsiveness to polysaccharide Ags could be due to the inability of a non-B cell population resident in the neonatal spleen to secrete sufficient quantities of IL-1.
Collapse
Affiliation(s)
- R L Chelvarajan
- Department of Microbiology and Immunology, Sanders-Brown Research Center on Aging, University of Kentucky, Lexington 40536, USA
| | | | | |
Collapse
|