Abstract
BackgroundA novel anti-mouse CD3ε antibody, Dow2, recognizes mouse CD3ε without activating T cells and suppresses T-cell activation. The purpose of this study was to determine whether Dow2 can inhibit T cells in uveitis.MethodsExperimental autoimmune uveitis (EAU) was induced in mice by immunization with retinal peptides, followed by administration of Dow2. Inflammation was evaluated by color fundus photography, optical coherence tomography, fluorescein angiography, and histology. Intraocular cells from EAU mice were used to examine the effect of Dow2 on retinal antigen-specific T cells. The effects of Dow2, conventional CD3ε antibodies, and isotype control immunoglobulin G (IgG) on splenic T cells were compared by assessing cell proliferation by the mixed lymphocyte reaction assay, inflammatory cytokine production by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry, and gene expression by quantitative reverse-transcription polymerase chain reaction (RT-PCR). T-cell subpopulations were characterized by flow cytometry to evaluate the expression of CD4, CD8, CD44, CD62L, and Foxp3.ResultsDow2 significantly reduced T-cell activation and counteracted activation associated with anti-CD3ε antibodies. Unlike conventional CD3ε antibodies, Dow2 treatment did not upregulate T helper (Th)1-/Th17-associated gene expression and cytokine production in splenic T cells. Interferon (IFN)-γ production by retinal antigen-specific T cells was also significantly reduced. Ocular inflammation was significantly reduced in Dow2-treated EAU mice compared to control EAU mice, with fewer T cells infiltrating into the retinas of Dow2-treated EAU mice. In immunohistochemistry, Th1 and Th17 cells invaded the retina in control EAU mice but not Dow2-treated EAU mice. No effects on peripheral T-cell numbers were observed following systemic administration of Dow2.ConclusionThe novel anti-CD3 antibody Dow2 can inhibit T cell-mediated inflammation in uveitis models. Thus, inhibition of T-cell activation by anti-CD3 therapy with this new antibody may protect uveitis patients from severe ocular inflammation.
Highlights
A novel anti-mouse CD3ε antibody, Dow2, recognizes mouse CD3ε without activating T cells and suppresses T-cell activation
T cells stained with Dow2 demonstrated a clear separation from the control T-cell population, comparable to the separation observed for T cells stained with 17A2 or 145-2C11 (Fig. 1a)
carboxyfluorescein succinimidyl ester (CFSE)-labeled C57BL/6JJcl splenocytes cocultured with irradiated BALB/c splenocytes were incubated with Dow2, 17A2, or isotype control
Summary
A novel anti-mouse CD3ε antibody, Dow, recognizes mouse CD3ε without activating T cells and suppresses T-cell activation. Immune privilege in the eye may degrade and permit the infiltration of proinflammatory immune cells. These immune cells include T cells, B cells, macrophages/monocytes, microglia, neutrophils, natural killer (NK)/NKT cells, and dendritic cells, which may invade the retina, choroid, vitreous, and anterior chambers of the eye. Initiation of the major pathological events in EAU mouse models occurs through immunization with retinal antigens, which activates retinal antigen-specific T cells [7]. Over time, these activated T cells produce inflammatory cytokines, T helper (Th) cytokines such as interferon (IFN)-γ and interleukin (IL)-2, which
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
