The Journal of Immunology, 2005, 175: 5611-5614.
Copyright © 2005 by The American Association of Immunologists
Cutting Edge: Macrophage Migration Inhibitory Factor Is Necessary for Progression of Experimental Autoimmune Encephalomyelitis1
Nicole D. Powell*,
Tracey L. Papenfuss*,
Melanie A. McClain*,
Ingrid E. Gienapp*,
Todd M. Shawler*,
Abhay R. Satoskar
and
Caroline C. Whitacre2,*
* Department of Molecular Virology, Immunology, and Medical Genetics and
Department of Microbiology, The Ohio State University, Columbus, OH 43210
 |
Abstract
|
|---|
Macrophage migration inhibitory factor (MIF) has been implicated in the pathogenesis of inflammatory and autoimmune diseases. The role of MIF in the progression of experimental autoimmune encephalomyelitis (EAE) was explored using MIF/ mice. Wild-type mice showed a progressive disease course, whereas MIF/ mice exhibited acute signs but no further progression of clinical disease. MIF/ mice displayed markedly elevated corticosterone levels and significant decreases in the inflammatory cytokines TNF-
, IFN-
, IL-2, and IL-6 before, during, and after EAE onset. Taken together, these findings support that MIF is an important mediator of EAE progression through glucocorticoid antagonism and up-regulation of the inflammatory response.
 |
Introduction
|
|---|
Macrophage migration inhibitory factor (MIF)3 has been shown to up-regulate proinflammatory cytokine production and antagonize glucocorticoid activity. These properties suggest that MIF may serve as a therapeutic target in the treatment of inflammatory autoimmune disease. MIF is a pleiotropic cytokine that is produced during inflammatory responses by many cells, including activated T cells, macrophages, and pituitary cells (1, 2, 3). MIF is constitutively expressed and is stored and released from intracellular pools. Unlike other proinflammatory cytokines, MIF secretion is induced, rather than inhibited, by glucocorticoid release (4).
Evidence suggests that glucocorticoids can influence the clinical course of inflammatory autoimmune diseases. Steroids have been widely used to treat relapses of multiple sclerosis (MS) and high doses of glucocorticoids administered during murine experimental autoimmune encephalomyelitis (EAE) relapses promote amelioration of EAE (5, 6). We have previously reported that mice producing high levels of corticosterone (CORT) induced by restraint stress showed reductions in disease severity and blocking CORT abrogated this effect. Glucocorticoids have been shown to potentiate a shift from Th1 cytokine production (IL-2 and IFN-
) to Th2 cytokines (IL-4 and IL-10), which have protective effects in MS and EAE (7, 8, 9, 10).
Studies in MS and EAE suggest that MIF may play a role in regulation of disease severity as well as in exacerbations of disease. Levels of MIF measured in the cerebrospinal fluid (CSF) of MS patients during relapse were significantly elevated relative to levels during remission (11). Increased levels of MIF were also found in the plasma of patients with sepsis and inflammatory bowel disease and were correlated with the severity of symptoms (12, 13). Importantly, MIF/ mice were shown to be resistant to sepsis and inflammatory bowel disease (13, 14, 15). In EAE, Denkinger et al. (16) reported that anti-MIF Ab treatment reduced the severity of clinical signs and accelerated recovery. Blockade of MIF activity by Ab impaired the migration of neuroantigen reactive T cells to the CNS by down-regulation of VCAM-1. In our study, a role for MIF in the acute as well as the progressive phases of EAE was examined using mice genetically depleted of MIF. We show here that MIF promotes EAE progression via glucocorticoid antagonism and regulation of inflammatory cytokine production.
 |
Materials and Methods
|
|---|
Induction and assessment of EAE
MIF / mice (B6;129S4-Miftm1Dvd), which were generated as previously described (14), or wild-type (WT) mice of the same strain combination (B6129) (Taconic Farms) were injected s.c. over four sites on the back with 100 µl containing 200 µg of myelin oligodendrocyte glycoprotein (MOG) 3555 peptide (Princeton Biomolecules) combined with complete Freunds adjuvant (containing 200 µg of heat-killed Mycobacterium tuberculosis Jamaica strain). Pertussis toxin (200 ng) (List Biological Laboratories) was injected i.p. in 0.2 ml of PBS at the time of immunization and 48 h later. All animals were observed daily for clinical signs and scored as described previously (5). Brains and spinal cords were examined for inflammatory cell infiltration by H&E staining. All animal procedures were performed in accordance with approved university protocols.
Measurement of CORT levels
Blood was obtained from the retroorbital plexus of anesthetized mice using heparinized tubes on days 10, 17, and 25 after MOG peptide immunization at the same time each day. Serum was collected and stored at 20°C. CORT levels were determined using a Correlate-EIA Corticosterone Immunoassay kit (Assay Designs).
Frequency of cytokine-producing cells by ELISPOT analysis
Spleen cells were harvested as described above and analyzed for frequency of IL-4- and IL-10-secreting cells by ELISPOT. The IL-4-secreting cell number was determined as described previously (17). IL-10-secreting cell number was determined using an IL-10 Development ELISPOT Module and Blue Color ELISPOT Module (R&D Systems). The plates were analyzed by computer-assisted image analysis using KS ELISPOT software and microscope control processor MCP4 (Carl Zeiss Vision).
Analysis of secreted cytokines by cytometric bead array
Spleens were obtained from immunized MIF/ or WT mice on days 10, 17, and 25 postimmunization. Spleen cells (4 x 105 cells/well) were cultured in 96-well plates together with medium, MOG 3555 (10 µg/ml), or anti-CD3 (2 µg/ml) for 72 h. Supernatants were harvested and cytokine analyses performed using the murine Th1/Th2 cytokine bead array (BD Biosciences). Flow cytometry was conducted on a FACSCalibur (BD Biosciences) with data analysis using CBA software (BD Pharmingen).
 |
Results and Discussion
|
|---|
Increased levels of MIF can be detected during periods of inflammation and exacerbation of disease; notably, elevation in MIF was detected in the CSF of MS patients during disease relapse but not during remission (11, 12, 13). To explore a causative role for MIF in relapse or progression of disease, we studied MIF during the course of EAE. B6129 WT mice and MIF-deficient mice (MIF/) were immunized with MOG 35-55 and adjuvants. As shown in Fig. 1, WT mice exhibit a progressive course of EAE. In contrast, MIF/ mice show signs of disease during the acute disease period but recover around day 20 postimmunization. As shown in Table I, MIF/ mice show no difference in clinical score relative to controls during the acute disease period. However, the cumulative disease score is significantly lower in the MIF/ group compared with the WT group. Furthermore, the number of cumulative periods of disease worsening in the MIF/ group was significantly lower compared with the WT mice, although the overall incidence of disease was not different between the two groups. We also examined the character and severity of CNS inflammation. Infiltrates were observed in the CNS of WT controls at day 17 but not in MIF/ mice. Interestingly, the extent of CNS inflammation was similar at day 25 (data not shown). Denkinger et al. (16) also showed a significant decrease in CNS infiltration in anti-MIF-treated mice compared with untreated controls. Our data suggest that MIF is less important for the induction phase of EAE but is a necessary factor for disease progression.
Several theories have been advanced to explain the transition from acute or progressive disease to remission or recovery. First, increased levels of steroid hormones, whether produced endogenously or introduced exogenously, can lead to amelioration of disease flares (5, 18). Because MIF has been shown to be a potent antagonist of glucocorticoid activity, it is possible that the absence of MIF in MIF/ animals allows for elevations in glucocorticoid hormones contributing to protection from disease. We measured CORT in the serum of MIF/ and WT mice at various times during the EAE disease course: before neuroantigen immunization (day 1), before the onset of clinical signs (day 10), during acute disease (day 17), and during the progressive phase of EAE (day 25). MIF/ animals display significantly higher levels of serum CORT compared with WT mice before and during acute EAE (Fig. 2), with elevations of CORT appearing as early as 3 days postimmunization (data not shown). To rule out the possibility that the dramatic difference in CORT levels between the MIF/ and WT animals could be due to a naturally increased hormone level in the MIF/ animals, levels of CORT in the serum of unimmunized MIF/ and WT mice were tested. Both MIF/ and WT mice had negligible basal levels of serum CORT (Fig. 2). As with high-dose glucocorticoid therapy, it is possible that the increased levels of endogenous glucocorticoids may have rendered MIF/ animals resistant to glucocorticoids effects. To determine whether animals were CORT resistant, we tested the proliferative capacity of mitogen-stimulated spleen cells from WT and MIF/ animals in the presence of a range of doses of CORT. Lymphocytes from both MIF/ and WT groups showed decreased proliferative responses upon addition of CORT (data not shown). These results suggest that MIF is contributing to disease exacerbations via glucocorticoid antagonism.
A second theory to explain the shift from acute or progressive disease to a state of recovery or remission involves the balance of Th1 and Th2 cytokines. A progressive course of EAE is correlated with the production of proinflammatory Th1 cytokines such as IFN-
and TNF-
(19, 20). In contrast, Th2 cytokines, such as IL-4 and IL-10, in the CNS as well as in the periphery have been associated with reduced disease severity and recovery (21, 22, 23). Because MIF up-regulates proinflammatory Th1 cytokines, it is possible that the lack of MIF would promote a shift to a more Th2-like cytokine profile. We analyzed cytokine production in MIF/ and WT mice before the onset of disease, during acute EAE, and during the progressive phase of disease. As shown in Fig. 3, lymphoid cells from MIF/ animals produced IL-4 at a much higher frequency than WT lymphoid cells during acute EAE (Fig. 3A) in response to MOG3555 stimulation. In addition, we also observed an elevated frequency of cells producing IL-10 during the progressive phase of EAE (Fig. 3B). In contrast, levels of proinflammatory cytokines such as IFN-
(Fig. 4C) and TNF-
(Fig. 4B) were significantly decreased in MIF/ animals before the onset of disease and during acute disease, respectively. In addition, IL-6 (Fig. 4A) and TNF-
(Fig. 4B) levels in the MIF/ mice were significantly decreased during disease progression. These data show that MIF may be influencing disease progression through the up-regulation of Th1 cytokines.
When analyzing the clinical, hormonal, and cytokine data together, two events seem to be critically important. First, the lack of MIF antagonism of CORT leads to increased levels of CORT beginning soon after MOG3555 peptide immunization. The increase in CORT levels leads to the second important event, which is a profound decrease in IFN-
during early disease. A reciprocal relationship between CORT and IFN-
is also seen later when decreasing levels of CORT in the MIF-deficient animals at day 25 correlate with an elevation in IFN-
. Interestingly, IFN-
has also been shown to be important in the control and regulation of EAE exacerbation (24, 25, 26). Elevated levels of glucocorticoids during acute EAE in the MIF/ mice also likely contribute to increases in IL-10, which is important for EAE recovery. In addition, IL-6 and TNF-
, two cytokines that stimulate the synthesis of glucocorticoids and in turn are inhibited by glucocorticoids (27, 28), are significantly decreased after CORT elevation in MIF/ animals. Our data indicate that the relationship between MIF and glucocorticoids may have a significant influence on the course of disease and that the elevation in glucocorticoids produces an alteration in disease progression due to modulation of cytokine production.
Glucocorticoids are an essential part of the homeostatic mechanism regulating the immune and endocrine systems. Those individuals with chronic inflammatory disorders, such as MS, have been successfully treated with glucocorticoids for a finite period of time. However, no long-term benefit has been identified and dose-limiting side effects are consequences of long-term glucocorticoid therapy (29). In EAE, exogenous administration of glucocorticoids results in suppression of EAE, a decrease in lymphoid cell numbers, and a decrease in Thl cytokine production (5). In this study, we propose that a relationship exists between MIF and glucocorticoid hormone levels. It has been shown previously by Fingerle-Rowson et al. (30) that exogenous glucocorticoids administered to rats induce increased levels of MIF in the blood and tissue. Conversely, adrenalectomized rats showed no dysregulation in MIF production, indicating that MIF is affected by the presence of increased glucocorticoids but is not affected by the absence of endogenous glucocorticoids (30). To further understand the effects of MIF on EAE, the levels of MIF during the normal course of disease as well as in animals treated with CORT need to be determined. Although levels of MIF in the CSF have been shown to be elevated in patients during MS relapse, the levels of MIF after glucocorticoid treatment have not been determined in relapsing or progressive MS patients.
Collectively, our findings suggest that MIF plays a crucial role in mediating the progression of EAE. The mechanism by which MIF exerts its effects appears to be via glucocorticoid antagonism and by promotion of Th1 cytokines such as IL-6, IFN-
, and TNF-
. Our data also suggest a significant role for glucocorticoids and Th2 cytokines in the pathway to EAE remission and recovery. High levels of glucocorticoids, in the absence of MIF, influence both the clinical disease course and cytokine profiles in EAE affected animals. Therapeutic strategies targeting MIF regulation may provide new insights into the treatment of MS.
 |
Acknowledgments
|
|---|
We thank Shannon Durkin and Fei Song for helpful discussions and critical reading of the manuscript.
 |
Disclosures
|
|---|
The authors have no financial conflict of interest.
 |
Footnotes
|
|---|
The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
1 These studies were supported by National Institutes of Health Grant AI43376 and National Multiple Sclerosis Society Grants RG 3091 and RG 3272. 
2 Address correspondence and reprint requests to Dr. Caroline C. Whitacre, Department of Molecular Virology, Immunology and Medical Genetics, College of Medicine and Public Health, The Ohio State University, 260 Meiling Hall, 370 West 9th Avenue, Columbus, OH 43210. E-mail address: whitacre.3{at}osu.edu 
3 Abbreviations used in this paper: MIF, macrophage migration inhibitory factor; MS, multiple sclerosis; EAE, experimental autoimmune encephalomyelitis; CORT, corticosterone; CSF, cerebrospinal fluid; WT, wild type; MOG, myelin oligodendrocyte glycoprotein. 
Received for publication June 6, 2005.
Accepted for publication August 15, 2005.
 |
References
|
|---|
- Calandra, T., J. Bernhagen, R. A. Mitchell, R. Bucala. 1994. The macrophage is an important and previously unrecognized source of macrophage migration inhibitory factor. J. Exp. Med. 179:1895.-1902. [Abstract/Free Full Text]
- Bacher, M., C. N. Metz, T. Calandra, K. Mayer, J. Chesney, M. Lohoff, D. Gemsa, T. Donnelly, R. Bucala. 1996. An essential regulatory role for macrophage migration inhibitory factor in T cell activation. Proc. Natl. Acad. Sci. USA 93:7849.-7854. [Abstract/Free Full Text]
- Bernhagen, J., T. Calandra, R. A. Mitchell, S. B. Martin, K. J. Tracey, W. Voelter, K. R. Manogue, A. Cerami, R. Bucala. 1993. MIF is a pituitary-derived cytokine that potentiates lethal endotoxaemia. Nature 365:756.-759. [Medline]
- Calandra, T., J. Bernhagen, C. N. Metz, L. A. Spiegel, M. Bacher, T. Donnelly, A. Cerami, R. Bucala. 1995. MIF as a glucocorticoid-induced modulator of cytokine production. Nature 377:68.-71. [Medline]
- Dowdell, K. C., I. E. Gienapp, S. Stuckman, R. M. Wardrop, C. C. Whitacre. 1999. Neuroendocrine modulation of chronic relapsing experimental autoimmune encephalomyelitis: a critical role for the hypothalamic-pituitary-adrenal axis. J. Neuroimmunol. 100:243.-251. [Medline]
- Noseworthy, J. H., C. Lucchinetti, M. Rodriguez, B. G. Weinshenker. 2000. Multiple sclerosis. N. Engl. J. Med. 343:938.-952. [Free Full Text]
- Cua, D. J., D. R. Hinton, S. A. Stohlman. 1995. Self-antigen-induced Th2 responses in experimental allergic encephalomyelitis (EAE)-resistant mice: Th2-mediated suppression of autoimmune disease. J. Immunol. 155:4052.-4059. [Abstract]
- Blotta, M. H., R. H. DeKruyff, D. T. Umetsu. 1997. Corticosteroids inhibit IL-12 production in human monocytes and enhance their capacity to induce IL-4 synthesis in CD4+ lymphocytes. J. Immunol. 158:5589.-5595. [Abstract]
- Ramierz, F., D. J. Fowell, M. Puklavec, S. Simmonds, D. Mason. 1996. Glucocorticoids promote a Th2 cytokine response by CD4+ T cells in vitro. J. Immunol. 156:2406.-2412. [Abstract]
- Stohlman, S. A., L. Pei, D. J. Cua, Z. Li, D. R. Hinton. 1999. Activation of regulatory cells suppresses experimental allergic encephalomyelitis via secretion of IL-10. J. Immunol. 163:6338.-6344. [Abstract/Free Full Text]
- Niino, M., A. Ogata, S. Kikuchi, K. Tashiro, J. Nishihira. 2000. Macrophage migration inhibitory factor in the cerebrospinal fluid of patients with conventional and optic-spinal forms of multiple sclerosis and neuro-Behcets disease. J. Neurol. Sci. 179:127.-131. [Medline]
- Bozza, F. A., R. N. Gomes, A. M. Japiassu, M. Soares, H. C. Castro-Faria-Neto, P. T. Bozza, M. T. Bozza. 2004. Macrophage migration inhibitory factor levels correlate with fatal outcome in sepsis. Shock 22:309.-313. [Medline]
- de Jong, Y. P., A. C. Abadia-Molina, A. R. Satoskar, K. Clarke, S. T. Rietdijk, W. A. Faubion, E. Mizoguchi, C. N. Metz, M. Alsahli, T. ten Hove, et al 2001. Development of chronic colitis is dependent on the cytokine MIF. Nat. Immunol. 2:1061.-1066. [Medline]
- Bozza, M., A. R. Satoskar, G. Lin, B. Lu, A. A. Humbles, C. Gerard, J. R. David. 1999. Targeted disruption of migration inhibitory factor gene reveals its critical role in sepsis. J. Exp. Med. 189:341.-346. [Abstract/Free Full Text]
- Calandra, T., B. Echtenacher, D. L. Roy, J. Pugin, C. N. Metz, L. Hultner, D. Heumann, D. Mannel, R. Bucala, M. P. Glauser. 2000. Protection from septic shock by neutralization of macrophage migration inhibitory factor. Nat. Med. 6:164.-170. [Medline]
- Denkinger, C. M., M. Denkinger, J. J. Kort, C. Metz, T. G. Forsthuber. 2003. In vivo blockade of macrophage migration inhibitory factor ameliorates acute experimental autoimmune encephalomyelitis by impairing the homing of encephalitogenic T cells to the central nervous system. J. Immunol. 170:1274.-1282. [Abstract/Free Full Text]
- Benson, J. M., K. A. Campbell, Z. Guan, I. E. Gienapp, S. S. Stuckman, T. Forsthuber, C. C. Whitacre. 2000. T cell activation and receptor down-modulation precede deletion induced by mucosally administered antigen. J. Clin. Invest. 106:1031.-1038. [Medline]
- Whitacre, C. C., K. Dowdell, A. C. Griffin. 1998. Neuroendocrine influences on experimental autoimmune encephalomyelitis. Ann. NY Acad. Sci. 840:705.-716. [Abstract/Free Full Text]
- Ando, D. G., J. Clayton, D. Kono, J. L. Urban, E. E. Sercarz. 1989. Encephalitogenic T cells in the B10.PL model of experimental allergic encephalomyelitis (EAE) are of the Th-1 lymphokine subtype. Cell. Immunol. 124:132.-143. [Medline]
- Tanuma, N., T. Shin, K. Kogure, Y. Matsumoto. 1999. Differential role of TNF-
and IFN-
in the brain of rats with chronic relapsing autoimmune encephalomyelitis. J. Neuroimmunol. 96:73.-79. [Medline]
- Bettelli, E., M. P. Das, E. D. Howard, H. L. Weiner, R. A. Sobel, V. K. Kuchroo. 1998. IL-10 is critical in the regulation of autoimmune encephalomyelitis as demonstrated by studies of IL-10- and IL-4-deficient and transgenic mice. J. Immunol. 161:3299.-3306. [Abstract/Free Full Text]
- Zhang, X., D. N. Koldzic, L. Izikson, J. Reddy, R. F. Nazareno, S. Sakaguchi, V. K. Kuchroo, H. L. Weiner. 2004. IL-10 is involved in the suppression of experimental autoimmune encephalomyelitis by CD25+CD4+ regulatory T cells. Int. Immunol. 16:249.-256. [Abstract/Free Full Text]
- Cua, D. J., B. Hutchins, D. M. LaFace, S. A. Stohlman, R. L. Coffman. 2001. Central nervous system expression of IL-10 inhibits autoimmune encephalomyelitis. J. Immunol. 166:602.-608. [Abstract/Free Full Text]
- Chu, C. Q., S. Wittmer, D. K. Dalton. 2000. Failure to suppress the expansion of the activated CD4 T cell population in interferon
-deficient mice leads to exacerbation of experimental autoimmune encephalomyelitis. J. Exp. Med. 192:123.-128. [Abstract/Free Full Text]
- Ferber, I. A., S. Brocke, C. Taylor-Edwards, W. Ridgway, C. Dinisco, L. Steinman, D. Dalton, C. G. Fathman. 1996. Mice with a disrupted IFN-
gene are susceptible to the induction of experimental autoimmune encephalomyelitis (EAE). J. Immunol. 156:5.-7. [Abstract]
- Willenborg, D. O., S. Fordham, C. C. Bernard, W. B. Cowden, I. A. Ramshaw. 1996. IFN-
plays a critical down-regulatory role in the induction and effector phase of myelin oligodendrocyte glycoprotein-induced autoimmune encephalomyelitis. J. Immunol. 157:3223.-3227. [Abstract]
- Turnbull, A. V., C. L. Rivier. 1999. Regulation of the hypothalamic-pituitary-adrenal axis by cytokines: actions and mechanisms of action. Physiol. Rev. 79:1.-71. [Abstract/Free Full Text]
- Hawes, A. S., C. S. Rock, C. V. Keogh, S. F. Lowry, S. E. Calvano. 1992. In vivo effects of the antiglucocorticoid RU 486 on glucocorticoid and cytokine responses to Escherichia coli endotoxin. Infect. Immun. 60:2641.-2647. [Abstract/Free Full Text]
- Pender, M. P., N. P. Wolfe. 2002. Prevention of autoimmune attack and disease progression in multiple sclerosis: current therapies and future prospects. Intern. Med. J. 32:554.-563. [Medline]
- Fingerle-Rowson, G., P. Koch, R. Bikoff, X. Lin, C. N. Metz, F. S. Dhabhar, A. Meinhardt, R. Bucala. 2003. Regulation of macrophage migration inhibitory factor expression by glucocorticoids in vivo. Am. J. Pathol. 162:47.-56. [Abstract/Free Full Text]
Related articles in The JI:
- IN THIS ISSUE
The JI 2005 175: 5565-5566.
[Full Text]
This article has been cited by other articles:

|
 |

|
 |
 
C. A. Learn, P. E. Fecci, R. J. Schmittling, W. Xie, I. Karikari, D. A. Mitchell, G. E. Archer, Z. Wei, H. Dressman, and J. H. Sampson
Profiling of CD4+, CD8+, and CD4+CD25+CD45RO+FoxP3+ T Cells in Patients with Malignant Glioma Reveals Differential Expression of the Immunologic Transcriptome Compared with T Cells from Healthy Volunteers
Clin. Cancer Res.,
December 15, 2006;
12(24):
7306 - 7315.
[Abstract]
[Full Text]
[PDF]
|
 |
|