Fc gamma receptor (FcγR) expression correlates with the presence of T cells in rheumatoid arthritis (RA) synovium

<p><b>Copyright information:</b></p><p>Taken from "High synovial expression of the inhibitory FcγRIIb in rheumatoid arthritis"</p><p>http://arthritis-research.com/content/9/3/R51</p><p>Arthritis Research & Therapy 2007;9(3):R51-R51.</p><p>Published online 23 May 2007</p><p>PMCID:PMC2206344.</p><p></p> Sequentially sectioned synovial tissue from a late stage RA patient demonstrating FcγRI, II and III positive cells perivasculary. The FcγR positive cells are located in the same area as CD3 positive T cells. Note the FcγRIII positive cell inside the vessel. This staining was representative of all other late RA synovial tissues stained in the same way (= 26). The IgG1 isotype control did not show any background (data not shown). (Original magnification ×250.) The expression of FcγRI, II and III was significantly correlated with the expression of CD3 in RA synovium (each symbol represents one patient, = 26)

Co-localisation of CD163 with Fc gamma receptor (FcγR)I, II, IIb and III

<p><b>Copyright information:</b></p><p>Taken from "High synovial expression of the inhibitory FcγRIIb in rheumatoid arthritis"</p><p>http://arthritis-research.com/content/9/3/R51</p><p>Arthritis Research & Therapy 2007;9(3):R51-R51.</p><p>Published online 23 May 2007</p><p>PMCID:PMC2206344.</p><p></p> Rheumatoid arthritis synovial tissue showed overlapping expression of the macrophage marker CD163 with the expression of FcγRI (a), FcγRII (b), FcγRIIb (c) and FcγRIII (d). The majority of the CD163 positive macrophages expressed FcγRIIb. However, note that a CD163 positive cell lacked FcγRIIb expression. (Original magnification ×400.

Expression of Fc gamma receptor (FcγR)IIb in healthy and rheumatoid arthritis (RA) synovia

<p><b>Copyright information:</b></p><p>Taken from "High synovial expression of the inhibitory FcγRIIb in rheumatoid arthritis"</p><p>http://arthritis-research.com/content/9/3/R51</p><p>Arthritis Research & Therapy 2007;9(3):R51-R51.</p><p>Published online 23 May 2007</p><p>PMCID:PMC2206344.</p><p></p> (a) FcγRIIb was sparsely expressed in the few healthy synovial biopsies that were positively stained by GB3. The arrows indicate FcγRIIb positive cells in the sub-lining synovial layer and tissue. (b) The IgG1 isotype control antibody did not stain the healthy synovium. (c,e) Positive FcγRIIb expression was found in all the stained RA synovial biopsies. FcγRIIb staining was observed in the synovial lining and sub-lining layers, perivasculary and inside lymphocyte infiltrates (e). (d) No staining of the RA synovium was observed when the anti-FcγRIIb monoclonal antibody was bound by recombinant human soluble FcγRIIb prior to staining. (f) Synovial FcγRIIb expression was significantly up-regulated in RA patients (= 10) compared to healthy individuals (= 5) (mean values of two independent observers, SEM and SK with standard error of the mean, *= 0.0104). DAB, diaminobenzidine. (Original magnification ×125.

Increased Fc gamma receptor (FcγR)I, II and III expression in rheumatoid arthritis (RA) synovia

<p><b>Copyright information:</b></p><p>Taken from "High synovial expression of the inhibitory FcγRIIb in rheumatoid arthritis"</p><p>http://arthritis-research.com/content/9/3/R51</p><p>Arthritis Research & Therapy 2007;9(3):R51-R51.</p><p>Published online 23 May 2007</p><p>PMCID:PMC2206344.</p><p></p> Sequentially sectioned synovial biopsy from a healthy individual demonstrating FcγRII and III, but not FcγRI, positive cells. The same expression pattern was seen in all healthy volunteers studied (= 10). (Original magnification ×250.) Sequentially sectioned synovial tissue from a RA patient demonstrating FcγRI, II and III positive cells in the synovial lining and sub-lining layers and perivasculary. Note the dense staining of FcγRIII in the synovial lining layer. The FcγR stainings were representative of all other RA tissues stained (= 26). IgG1 isotype control stainings were included for all the patient material used. (Original magnification ×125.) The expression of FcγRs in healthy (= 10), early (= 11) and late RA (= 15) synovial tissue was evaluated and compared. Note that FcγRI was not detected in healthy synovial tissue and that FcγRI, FcγRII and III were significantly more expressed in both early and late RA synovial tissue compared to healthy synovia (mean values of two independent observers, SEM and SK with standard error of the mean; **< 0.01; ***< 0.001). DAB, diaminobenzidine

Decreased Fc gamma receptor (FcγR) expression after local treatment with glucocorticoids

<p><b>Copyright information:</b></p><p>Taken from "High synovial expression of the inhibitory FcγRIIb in rheumatoid arthritis"</p><p>http://arthritis-research.com/content/9/3/R51</p><p>Arthritis Research & Therapy 2007;9(3):R51-R51.</p><p>Published online 23 May 2007</p><p>PMCID:PMC2206344.</p><p></p> Immunohistochemical staining of FcγRs and macrophages (CD163) in arthritic synovial tissue (= 9) before and after local glucocorticoid treatment of the joint was analysed. The FcγRI expression was significantly decreased after treatment (*< 0.05) and there was a trend towards decreased expression of FcγRII (= 0.074). Staining of FcγRI on arthritic synovial biopsy, taken before and after one intraarticular injection of glucocorticoids, from the same biopsy area and patient. Note the reduced FcγRI staining after treatment (c). DAB, diaminobenzidine