Differential tissue expression of erythroblast macrophage protein in a MRL/lpr mouse model of lupus

Abstract

Objective

The objective of this study was to observe the expression features of erythroblast macrophage protein (EMP) between the tissues of MRL/lpr mice, a mouse model of systemic lupus erythematosus (SLE), and control mice.

Methods

We examined the serum ANA in both mice groups through indirect immunofluorescence (IIF). Expression features of EMP in bone marrow, liver, renal, spleen, brain, and lung tissues of the MRL/lpr mice and control mice groups were followed using quantitative real-time polymerase chain reaction (Q-PCR). Meanwhile, the expression of EMP was located through immunohistochemical (IHC) studies and the expressive cell identified through double immunofluorescent labeling.

Results

IIF showed that lupus mice have strong positive fluorescence, but no significant fluorescence was observed in control mice. Q-PCR detection revealed that EMP was expressed in the marrow, liver, renal, spleen, lung, and brain tissues of lupus mice. The highest levels were observed in the bone marrow, but there was no statistical difference between these tissues. EMP mRNA expression in the liver (t = 2.747, p = 0.01) and bone marrow (t = 3.853, p = 0.008) of lupus mice was significantly higher than in the control mice. However, no differences in EMP mRNA expression were observed in the renal, spleen, lung, and brain tissues between the lupus and control mice (p > 0.05). In addition, the IHC results showed that EMP protein is ubiquitously expressed in all of the tissues of the lupus and control mice. The positive expression rate in the bone marrow and liver tissues of the lupus mice was higher than in the control mice, but without an obvious difference in the other tissues. The double IF staining method shows that EMP protein was expressed in macrophages in the tissues of the lupus mice and the control mice.

Conclusions

Our data showed that EMP is ubiquitously expressed in macrophages at all of the tissues of the lupus and control mice. However, the expression of EMP in bone marrow and liver tissues of lupus mice was higher than in the control mice, which indicates that EMP may be important in the development of SLE.

Keywords

Erythroblast macrophage protein systemic lupus erythematosus antinuclear antibodies MRL/lpr model

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References

Ahmadpoor

Dalili

Rostami

. An update on pathogenesis of systemic lupus erythematosus. Iran J Renal Dis 2014; 8: 171–184.

Dai

Zhang

Liu

Chen

. Progress in the study on autoantibodies of systemic lupus erythematosus. Int J Immunol 2014; 37: 419–423.

Xia

. Study on the mechanism and pathogenicity of IgG-type anti double chain DNA antibodies. Int J Immunol 2007; 30: 425–428.

Choi

Kim

Craft

. The pathogenesis of systemic lupus erythematosus: an update. Curr Opin Immunol 2012; 24: 651–665.

Invernizzi P. Brief introduction to antinuclear antibodies. In: Zou H (ed) Autoantibodies. 1st ed. Beijing: People’s Medical Publishing House, 2009, pp.99–103.

Lateef

Petri

. Unmet medical needs in systemic lupus erythematosus. Arthritis Res Ther 2012; 14: S4–S4.

Hanspal

. The association of erythroblasts with macrophages promotes erythroid proliferation and maturation: a 30-kD heparin-binding protein is involved in this contact. Blood 1994; 84: 3494–3504.

Javan

Salhotra

Finley

et al.

Erythroblast macrophage protein (EMP): past, present, and future. Eur J Haematol 2018; 100: 3–9.

Belay

Hayes

Blau

et al.

Human cord blood and bone marrow CD34+ cells generate macrophages that support erythroid islands. PLoS One 2017; 12: e0171096–e0171096.

10.

Kangli

Fan

Cheng

. Research progress of erythroblast-macrophage protein in bone marrow erythroblastic islands. J New Med 2017; 45: 209–212.

11.

Javan

Can

Yeboah

et al.

Novel interactions between erythroblast macrophage protein and cell migration. Blood Cells Mol Dis 2016; 60: 24–27.

12.

Soni

Bala

Gwynn

Sahr

Peters

Hanspal

. Absence of erythroblast macrophage protein (Emp) leads to failure of erythroblast nuclear extrusion. J Biol Chem 2006; 281: 20181–20189.

13.

Mao

Shi

Liu

. Evaluation of erythroblast macrophage protein related to erythroblastic islands in patients with hematopoietic stem cell transplantation. Eur J Med Res 2013; 18: 1–9.

14.

Fischer

Kurbatova

Bessonov

Gandrillon

Volpert

Crauste

. Modeling erythroblastic islands: using a hybrid model to assess the function of central macrophage. Theor Biol 2012; 298: 92–106.

15.

Cheng

X-P

Lai

M-S

Fan

et al.

Effects of nourishing yin and clearing heat herbs on bone marrow EMP and anti-ds-DNA antibody in tissue of lupus mice. Transl Med J 2016; 3: 8–10.

16.

Liu

Zhang

Zheng

et al.

Expression and regulation of osteopontin in chronic rhinosinusitis with nasal polyps. Clin Exp Allergy 2015; 45: 414–422.

17.

Yokoyama

Etoh

Kitagawa

et al.

Migration of erythroblastic islands toward the sinusoid as erythroid maturation proceeds in rat bone marrow. J Vet Med Sci 2003; 65: 449–452.

18.

Soni

Bala

Kumar

et al.

Changing pattern of the subcelluar distribution of erythroblast macrophage protein (EMP) during macrophage differentiation. Blood Cells Mol Dis 2007; 38: 25–31.

19.

Wang

W-H

Shi

Wang

et al.

Macrophage activation syndrome. Chin J Appl Clin Pediatr 2006; 21: 179–182.

20.

J-Z

Zeng

Xiao

. Reactive hemophagocytic syndrome and systemic lupus erythematosus. Chin J Rheumatol 2000; 4: 382–384.

21.

Soni

Bala

Hanspal

. Requirement for erythroblast-macrophage protein (EMP) in definitive erythropoiesis. Blood Cells Mol Dis 2008; 41: 141–147.

22.

An Y. Innate immune system and its mediated immune response. Section 1. Composition of inherent immune system. In: Cao X (ed) Medical immunology. Beijing: People’s Medical Publishing House, 2013, pp.6–120.

23.

Stehbens

Wittmann

. Targeting and transport: how microtubules control focal adhesion dynamics. J Cell Biol 2012; 198: 481–489.

24.

Wynn

Chawla

Pollard

. Macrophage biology in development, homoeostasis and disease. Nature 2013; 496: 445–455.