Engraftment of peripheral blood mononuclear cells from systemic lupus erythematosus and antiphospholipid syndrome patient donors into BALB‐RAG‐2^−/−IL‐2Rγ^−/− mice: A promising model for studying human disease

Abstract

Objective. To construct a humanized mouse model of systemic lupus erythematosus (SLE) that resembles the human disease in order to define the pathophysiology and targets for treatments.Methods. We infused peripheral blood mononuclear cells (PBMCs) from SLE patients into BALB-RAG-2 -/-IL-2R␥ -/-double-knockout (DKO) mice, which lack T cells, B cells, and natural killer cells. PBMCs from 5 SLE patients and 4 normal donors were infused intravenously/intraperitoneally at a density of 3-5 ؋ 10 6 cells per animal into nonirradiated 4-5-week-old mice. We evaluated the engraftment of human CD45؉ cells and monitored the plasma levels of human IgG, antidouble-stranded DNA (anti-dsDNA) antibody, and anticardiolipin antibody (aCL), as well as proteinuria and kidney histology.Results. There was 100% successful engraftment in 40 DKO mice infused with human PBMCs. In the PBMC fraction from SLE PBMC-infused DKO (SLE-DKO) mice and normal donor PBMC-infused DKO (ND-DKO) mice, an average of 41% and 53% human CD45؉ cells, respectively, were observed at 4 weeks postengraftment, with 70-90% CD3؉ cells. There were fewer CD3؉CD4؉ cells (mean ؎ SEM 5.5 ؎ 2.1%) and more CD3؉CD8؉ cells (79.4 ؎ 3.6%) in the SLE-DKO mice as in the SLE patients from which the PBMCs were derived. CD19؉ B cells and CD11c؉ monocytic cells were found in the spleen, lung, liver, and bone marrow. There was no significant difference in plasma levels of human IgG and anti-dsDNA antibodies between SLE-DKO and ND-DKO mice. Levels of aCL were significantly higher in all SLE-DKO mice infused with PBMCs from an SLE patient who had high titers of aCL. SLE-DKO mice had proteinuria, human IgG deposits in the kidneys, and a shorter life span. In SLE-DKO mice engrafted with PBMCs from the aCL-positive patient, we found microthrombi and infiltration of CD3؉, CD8؉, and CD19؉ cells in the glomeruli, recapitulating the human antiphospholipid syndrome in these mice.Conclusion. We established a novel humanized SLE-DKO mouse exhibiting many of the immunologic and clinical features of human SLE.

Differential Expression of the Transcription Factor ARID3a in Lupus Patient Hematopoietic Progenitor Cells

“…Serum from recipient mice were diluted 1:4 or 1:8 in PBS (27) and applied to fixed and permeabilized HEp-2 anti-nuclear Ab (ANA) slides using the NOVA Lite HEp-2 ANA kit (INOVA Diagnostics) to test for the presence of human Ig as previously described (28). Antibodies to nuclear antigens were detected using a secondary FITC-conjugated anti-human Ig antibody (Jackson Immunoresearch Laboratories) and visualized using a Zeiss Axioplan 2i inverted microscope with an AxioCam HRm camera (Carl Zeiss).…”

Humanized Mice as Unique Tools for Human-Specific Studies

“…Similar to patients, when these mice were treated with dexamethasone, spleen weight, and proteinuria decreased. Mice with a human immune system xenografted with patient samples allow a spectrum of disorders such as SLE (Andrade et al 2011; Gunawan et al 2017) and type I diabetes (Shultz et al 2007; Unger et al 2012; Viehmann Milam et al 2014) to be evaluated for the identification of screening markers, retrieval of antigen-specific autoantibodies, and drug tests. Autoimmune diseases that have been studied using humanized mice as a platform are listed in Table 6.…”

Lymphocytic abnormalities in a mother suggesting transient antiphospholipid antibodies during a previous unsuccesful pregnancy

“…In the peripheral blood mononuclear cells (PBMC) fraction from SLE PBMC-infused DKO (SLE-DKO) mice and normal donor PBMC-infused DKO (ND-DKO) mice, an average of 41% and 53% human CD45+ cells, respectively, were observed at 4 weeks post-engraftment, with 70-90% CD3+ cells (25). There were fewer CD3+CD4+ cells and more CD3+ cells in the SLE-DKO mice as in the SLE patients from which the PBMCs were derived.…”