Nuclei visualized using cresyl violet staining (blue). DTH lesion, but (F) no immunopositive cells were present in the NAWM. acn30001-0659-sd2.tif (3.5M) GUID:?97B329A5-8556-4FEC-919D-2C496DD05674 Figure S2: Twelve days of FTY720 treatment did not affect the distribution or number splenic B-cells or T-cells. (A) Immunostaining of 68-IB3-positive B-cells (brown) in rat splenic follicles in an FTY720-treated animal. (B) Staining for anti-OX22 revealed that FTY720 therapy did not alter the number of T-cells present in the spleen. acn30001-0659-sd3.tif (3.4M) GUID:?16FAC7C4-5443-44CD-A27C-E7CC9892FFAB Figure S3: Anti CD20 treatment reduces the area of microglial activation both in the lesion core and the surrounding tissue. This area was calculated by measuring the area of OX6-positive immunohistochemistry staining. acn30001-0659-sd4.tif (168K) GUID:?6CD66269-D7D6-4599-81AC-7F66E1C618DA Figure S4: [123I]-DPA-713 autoradiographic confirmation of decreased activated microglia in anti-CD20-treated DTH model Lotilaner of MS. (A) Increased activated microglia at the site of lesion in untreated DTH model of MS. (B) Decreased activated microglia at the site of lesion in anti-CD20-treated DTH model of MS. (C) Ratio or radioligand uptake in the basal ganglia and overlying cortex in ipsilateral versus contralateral hemispheres, *= 0.047. acn30001-0659-sd5.tif (465K) GUID:?3963ED85-38B3-4842-BCF1-B1225349164A Figure S5: Effect of Anti-CD20 treatment interaction of T cells and B cells with the BV2 microglial cell line. (A) The number of B and T cell recovered from control antibody or anti-CD20-treated animals. (B) Graph of the effect of LPS or T cells from control or anti-CD20-treated animals on TNF release by BV2 cells. (C) Graph of the effect of LPS or T cells from control or anti-CD20-treated animals on TNF release by BV2 Lotilaner cells. Note that LPS elicits markedly increased TNF production compared to the effects of the T or B cells alone. Anti-CD20 therapy had no impact on the outcome. acn30001-0659-sd6.tif (170K) GUID:?A094DC63-8638-4B8F-AC28-6B2C7BDD01F4 Abstract Objective The mechanism of action of anti-B cell therapy in multiple sclerosis (MS) is not fully understood. Here, we compared the effect of anti-CD20 therapy Rabbit Polyclonal to MP68 on microglial activation in two distinct focal rat models of MS. Methods The effect of anti-CD20 therapy on lesion formation and extralesional microglial activation was evaluated in the fDTH-EAE (experimental allergic encephalomyelitis) model, which is a focal demyelinating type-IV delayed-type hypersensitivity lesion. For comparison, effects were also assessed in the focal humoral MOG model induced by intracerebral injection of cytokine in myelin oligodendrocyte glycoprotein immunized rats. Microglial activation was assessed and using the TSPO SPECT ligand [125I]DPA-713, and by immunostaining for MHCII. The effect of treatment on demyelination and lymphocyte recruitment to the brain were evaluated. Results Anti-CD20 therapy reduced microglial activation, and lesion formation in the humoral model, but it was most effective in the antibody-independent fDTH-EAE. Immunohistochemistry for MHCII also demonstrated a reduced volume of microglial activation in the brains of anti-CD20-treated fDTH-EAE animals, which was accompanied by a reduction in T-cell recruitment and demyelination. The effect anti-CD20 therapy in the latter model was similarly strong as compared to the T-cell targeting MS compound FTY720. Interpretation The suppression of lesion development by anti-CD20 treatment in an antibody-independent model suggests that B-cells play an important role in lesion development, independent of auto-antibody production. Thus, CD20-positive B-cell depletion has the potential to be effective in a wider population of individuals with MS than might have been predicted from our knowledge of the underlying histopathology. Introduction Multiple sclerosis (MS) is an inflammatory demyelinating and neurodegenerative disease of the CNS central nervous system (CNS) with both focal and diffuse pathology.1 An aberrant T-cell response has been assumed to be the predominant pathophysiological mechanism2 and current Lotilaner standard therapies such as interferon, glatiramer acetate, natalizumab, and FTY720 (fingolimod) have been developed based on this concept.3 However, numerous histopathological studies have established that focal lesion formation is a heterogeneous process that can be divided into four distinct patterns.4 About half of the lesions are characterized by mechanisms that result in complement deposition, including C1q and terminal complement complex (TCC), which, when coupled to other long-known features (elevated IgG index, presence of oligoclonal bands, and specific autoantibodies in.
