Contributions
Abstract: EP1482
Type: Poster Sessions
Abstract Category: Pathology and pathogenesis of MS - Immunology
Background: Recent experience with new available immunomodulatory treatments depleting B cells has revealed the crucial role of this immune cell type in multiple sclerosis (MS) pathogenesis. Specifically, there is increasing evidence that lower frequency of B cells and particularly, memory B cells are associated with optimal response to immunomodulatory drugs. Thus, monitoring memory B cell population would be useful to assess the effectiveness of immunotherapies in MS patients.
However, there is little evidence related to the predictive role of their levels at MS diagnosis. For this reason, we aimed to study the basal levels of both B and memory B cells in MS patients and their relation to MS treatment approach.
Methods: A total of 28 individuals were included (11 controls and 17 MS patients). We defined controls as patients with non-MS neurological disease. Blood samples were collected from both controls and recently diagnosed MS patients and then peripheral blood mononuclear cells (PBMC) were isolated and frozen in liquid nitrogen. B (CD45+CD19+) and memory B cells (CD45+CD19+CD27+CD38-) were quantified from thawed PBMC by flow cytometry in an ACURI-C6 apparatus (BD Bioscience). Cells were stained with specific previously titrated anti-human antibodies: CD45-APC, CD19-PE-Cy7, CD27-PE and CD38-FITC.
Data were shown as percentage of B and memory B cells from total PBMC count. Mann-Whitney U test was used for comparisons between groups and Fisher's exact test to compare percentages.
Results: At the disease diagnosis, MS patients showed no differences in the percentage of neither B (p=0.404) nor memory B cells levels (p=0.860) when compared to controls.
Then, MS patients were classified as responders to moderate-efficacy treatments (MET) or patients who received high-efficacy treatments (HET) as the first treatment after MS diagnosis. We measured lower levels of B cells [MET: median 7.6 (IQR: 4.0) versus HET: median 4.3 (IQR: 3.5); p=0.056] and memory B cells [MET: median 3.1 (IQR: 2.1) versus HET: median 1.8 (IQR: 0.9); p=0.046] in patients with clinical and radiological data to consider HET strategies from disease onset.
Conclusions: These exploratory findings suggest that levels of memory B cells have to be taken into account during the selection of the optimal therapeutic strategy. Because of the small sample size and the slightly significant values, further research must be addressed to confirm these preliminary results.
Disclosure: Quintana E: nothing to disclose
Torras N: nothing to disclose
Muñoz-San Martín M: nothing to disclose
Tomàs-Roig J: nothing to disclose
Celarain N: nothing to disclose
Gómez I: nothing to disclose
Perkal H: nothing to disclose
Robles-Cedeño R: nothing to disclose
LluísRamió-Torrentà: has received compensation for consulting services and speaking honoraria from from Biogen, Novartis, Bayer, Merck, Sanofi, Genzyme, Teva Pharmaceutical Industries Ltd, Almirall, Mylan.
Abstract: EP1482
Type: Poster Sessions
Abstract Category: Pathology and pathogenesis of MS - Immunology
Background: Recent experience with new available immunomodulatory treatments depleting B cells has revealed the crucial role of this immune cell type in multiple sclerosis (MS) pathogenesis. Specifically, there is increasing evidence that lower frequency of B cells and particularly, memory B cells are associated with optimal response to immunomodulatory drugs. Thus, monitoring memory B cell population would be useful to assess the effectiveness of immunotherapies in MS patients.
However, there is little evidence related to the predictive role of their levels at MS diagnosis. For this reason, we aimed to study the basal levels of both B and memory B cells in MS patients and their relation to MS treatment approach.
Methods: A total of 28 individuals were included (11 controls and 17 MS patients). We defined controls as patients with non-MS neurological disease. Blood samples were collected from both controls and recently diagnosed MS patients and then peripheral blood mononuclear cells (PBMC) were isolated and frozen in liquid nitrogen. B (CD45+CD19+) and memory B cells (CD45+CD19+CD27+CD38-) were quantified from thawed PBMC by flow cytometry in an ACURI-C6 apparatus (BD Bioscience). Cells were stained with specific previously titrated anti-human antibodies: CD45-APC, CD19-PE-Cy7, CD27-PE and CD38-FITC.
Data were shown as percentage of B and memory B cells from total PBMC count. Mann-Whitney U test was used for comparisons between groups and Fisher's exact test to compare percentages.
Results: At the disease diagnosis, MS patients showed no differences in the percentage of neither B (p=0.404) nor memory B cells levels (p=0.860) when compared to controls.
Then, MS patients were classified as responders to moderate-efficacy treatments (MET) or patients who received high-efficacy treatments (HET) as the first treatment after MS diagnosis. We measured lower levels of B cells [MET: median 7.6 (IQR: 4.0) versus HET: median 4.3 (IQR: 3.5); p=0.056] and memory B cells [MET: median 3.1 (IQR: 2.1) versus HET: median 1.8 (IQR: 0.9); p=0.046] in patients with clinical and radiological data to consider HET strategies from disease onset.
Conclusions: These exploratory findings suggest that levels of memory B cells have to be taken into account during the selection of the optimal therapeutic strategy. Because of the small sample size and the slightly significant values, further research must be addressed to confirm these preliminary results.
Disclosure: Quintana E: nothing to disclose
Torras N: nothing to disclose
Muñoz-San Martín M: nothing to disclose
Tomàs-Roig J: nothing to disclose
Celarain N: nothing to disclose
Gómez I: nothing to disclose
Perkal H: nothing to disclose
Robles-Cedeño R: nothing to disclose
LluísRamió-Torrentà: has received compensation for consulting services and speaking honoraria from from Biogen, Novartis, Bayer, Merck, Sanofi, Genzyme, Teva Pharmaceutical Industries Ltd, Almirall, Mylan.