Contributions
Abstract: P683
Type: Poster
Abstract Category: Therapy - disease modifying - 26 Immunomodulation/Immunosuppression
Introduction: Dimethyl fumarate (DMF) is approved for patients with relapsing remitting Multiple Sclerosis (RRMS). We and others have shown that DMF reduces circulating lymphocytes, mainly CD8
T cells and B cells, and alters the proportions of B cell subsets, reducing memory B cells while increasing transitional B cells. The aim of this study was to assess the effect of DMF therapy on the cytokine profile of B and T cells in RRMS patients.
Methods: Blood was obtained from 23 RRMS patients about to initiate DMF therapy (12 1st line, 11 2nd line patients), before and 3.5 month (m) after treatment initiation. B and T cells were purified and cultured for 40 hours in 3 setups: B cells with/without anti-IgM/αCD40-stimulation; T cells with anti-CD3/CD28 + ionomycin/Phorbol 12-myristate 13-acetate stimulation; stimulated B cells co-cultured with stimulated baseline T cells used for both baseline and 3.5m setup to focus upon the drug effect on B cells. After 4h Golgistop, cells were stained for IL-10, TNFα, IFNγ, IL-4, TGFβ and Lymphtoxin-α (LTα) and analyzed by flow cytometry. IL-6 secretion from B cells was assessed by Cytometric bead array.
Results: In B cells cultured alone, 3m DMF therapy significantly increased the expression of TGFβ and IL10, mainly in 1st line patients, as well as % IL10+ B cells in 2nd line patients, while in 1st line patients % IL10+ B cells was reduced. % IL4+, LTα+ and TNFα+ B cells were reduced in 1st line patients, while % IFNγ+ B cells was increased (2nd line patients only). Furthermore, IL6 secretion was elevated (1st line patients). In B cells co-cultured with T cells, similar effects were found, including an increase in % TGFβ+ B cells (2nd line), while a reduction in % LTα and IL4 B cells (1st line). A reduction in % IL10+ B cells was found in 1st line patients, but their IL10 expression level was elevated (trend). In T cells cultured alone, 3m DMF therapy significantly reduced % TNFα+ and IFNγ+ as well as double-positive IFNγ+TNFα+ CD4
T cells. The expression levels of both LTα and TGFβ in CD4 T cells were increased, while no effect was found on IL10 or IL4. Baseline T cells co-cultured with B cells from DMF-treated patients, showed no change.
Conclusion: DMF therapy is associated with modulation of several lymphocyte cytokines, mainly with reduced pro-inflammatory cytokines such as: LTα in B cells and TNFα and IFNγ in T cells, while increased anti-inflammatory cytokines such as IL10 and TGFβ in B cells and TGFβ in T cells.
Disclosure: Study supported by an Investigator-Initiated Study grant from Biogen.
E.Najjar: nothing to disclose
E.Staun- Ram: nothing to disclose
A.Volkowich: nothing to disclose
D.Golan: nothing to disclose
A.Miller: nothing to disclose
Abstract: P683
Type: Poster
Abstract Category: Therapy - disease modifying - 26 Immunomodulation/Immunosuppression
Introduction: Dimethyl fumarate (DMF) is approved for patients with relapsing remitting Multiple Sclerosis (RRMS). We and others have shown that DMF reduces circulating lymphocytes, mainly CD8
T cells and B cells, and alters the proportions of B cell subsets, reducing memory B cells while increasing transitional B cells. The aim of this study was to assess the effect of DMF therapy on the cytokine profile of B and T cells in RRMS patients.
Methods: Blood was obtained from 23 RRMS patients about to initiate DMF therapy (12 1st line, 11 2nd line patients), before and 3.5 month (m) after treatment initiation. B and T cells were purified and cultured for 40 hours in 3 setups: B cells with/without anti-IgM/αCD40-stimulation; T cells with anti-CD3/CD28 + ionomycin/Phorbol 12-myristate 13-acetate stimulation; stimulated B cells co-cultured with stimulated baseline T cells used for both baseline and 3.5m setup to focus upon the drug effect on B cells. After 4h Golgistop, cells were stained for IL-10, TNFα, IFNγ, IL-4, TGFβ and Lymphtoxin-α (LTα) and analyzed by flow cytometry. IL-6 secretion from B cells was assessed by Cytometric bead array.
Results: In B cells cultured alone, 3m DMF therapy significantly increased the expression of TGFβ and IL10, mainly in 1st line patients, as well as % IL10+ B cells in 2nd line patients, while in 1st line patients % IL10+ B cells was reduced. % IL4+, LTα+ and TNFα+ B cells were reduced in 1st line patients, while % IFNγ+ B cells was increased (2nd line patients only). Furthermore, IL6 secretion was elevated (1st line patients). In B cells co-cultured with T cells, similar effects were found, including an increase in % TGFβ+ B cells (2nd line), while a reduction in % LTα and IL4 B cells (1st line). A reduction in % IL10+ B cells was found in 1st line patients, but their IL10 expression level was elevated (trend). In T cells cultured alone, 3m DMF therapy significantly reduced % TNFα+ and IFNγ+ as well as double-positive IFNγ+TNFα+ CD4
T cells. The expression levels of both LTα and TGFβ in CD4 T cells were increased, while no effect was found on IL10 or IL4. Baseline T cells co-cultured with B cells from DMF-treated patients, showed no change.
Conclusion: DMF therapy is associated with modulation of several lymphocyte cytokines, mainly with reduced pro-inflammatory cytokines such as: LTα in B cells and TNFα and IFNγ in T cells, while increased anti-inflammatory cytokines such as IL10 and TGFβ in B cells and TGFβ in T cells.
Disclosure: Study supported by an Investigator-Initiated Study grant from Biogen.
E.Najjar: nothing to disclose
E.Staun- Ram: nothing to disclose
A.Volkowich: nothing to disclose
D.Golan: nothing to disclose
A.Miller: nothing to disclose