University Hospital of Cologne
Neurology

Author Of 2 Presentations

Disease Modifying Therapies – Mechanism of Action Poster Presentation

P0287 - Alemtuzumab induces changes in the innate immune system in patients with relapsing-remitting multiple sclerosis (ID 722)

Speakers
Presentation Number
P0287
Presentation Topic
Disease Modifying Therapies – Mechanism of Action

Abstract

Background

Alemtuzumab is a humanized monoclonal antibody specific for CD52 and has been shown to be an efficient treatment for patients with relapsing-remitting multiple sclerosis (RRMS). CD52 is present at high expression levels on the surface of B- and T-lymphocytes and at low levels on monocytes and NK-cells. Recent evidence has emerged that the innate immune system might also undergo reorganization contributing to the long-lasting immunomodulatory properties of alemtuzumab.

Objectives

To better understand the effect of alemtuzumab on the innate immune system we longitudinally assessed the function of innate immune cells in a cohort of alemtuzumab treated RRMS patients. We particularly focused on distinguished monocyte and macrophage phenotypes to identify specific cellular activational patterns that are modulated during alemtuzumab treatment.

Methods

Peripheral mononuclear blood cells (PBMCs) and plasma were collected from RRMS patients before and every two months after alemtuzumab treatment for 12 months. PBMC surface marker (CD14, CD16, CD23, CD206, CD163, CD86, CCR7, HLA-DR) were assessed by flow cytometry. Monocyte function (phagocytosis of latex beads, ROS production) was examined by in vivo assays. Plasma cytokine levels were analyzed using ELISA.

Results

We observed an increase in the expression of anti-inflammatory surface markers such as CD206 and CD23 on the overall monocyte population. While the distribution of different monocyte phenotypes (classical, intermediate, and non-classical monocytes) did not change significantly after alemtuzumab treatment, several surface marker expressions within the individual phenotypes showed alterations. The CD16+ intermediate and non-classical monocytes showed an increase in anti-inflammatory CD23+, whereas the CD16- population displayed an elevation of pro-inflammatory CCR7 and CD86, 2 months post alemtuzumab treatment and a return to baseline levels later on. Furthermore, CD163+ monocytes, showing phagocytic activity were increased 6 months post-treatment and were still slightly elevated after 12 months, while phagocytosing B-cells showed an increase 12 months post alemtuzumab treatment

Conclusions

Alemtuzumab treatment goes along with complex alterations of the immune system including innate immunity mechanisms. In the peripheral blood compartment, PBMC display an increase in phagocytotic activity.

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Disease Modifying Therapies – Risk Management Poster Presentation

P0346 - Is the gut a relevant reservoir for persistent JCPyV infection? (ID 1327)

Speakers
Presentation Number
P0346
Presentation Topic
Disease Modifying Therapies – Risk Management

Abstract

Background

Natalizumab is an effective therapy for treatment of relapsing multiple sclerosis (MS). A serious side effect of natalizumab treatment is the occurrence of progressive multifocal leukoencephalopathy (PML) associated with JC polyomavirus (JCPyV) infection. A large fraction (20-30%) of individuals shed JCPyV DNA of wildtype variants in urine, yet around 50% of patients with the detection of anti-JCPyV antibodies in blood do not. PML-type JCPyV DNA variants have not been found in urine. Thus, the relevant reservoir of JCPyV remains unknown. We hypothesize that the gut may be this relevant reservoir and that natalizumab might alter the adaptive immunity in the gut. This could result in an increase in viral replication which would, in turn, facilitate viral genome alterations potentially inducing the formation of JCVPyV PML-type variants.

Objectives

Assessment of the gut as a potential reservoir for JC polyomavirus, associated with the development of progressive multifocal leukoencephalopathy.

Methods

The presence of JCPyV DNA in stool, urine and EDTA blood of natalizumab-treated MS patients (n=27; 22 female, 5 male) with known anti-JCPyV antibody index values in blood was assessed: antibody index above 1.5 (n=13), antibody index 1.5-0.9 (n=4), antibody index below 0.9 (n=4) and 6 with no detection of anti-JCPyV antibodies. Different DNA extraction methods and PCR techniques were applied and assay sensitivities assured performing spiking experiments.

Results

JCPyV DNA could not be detected in any of the EDTA blood or stool samples. Four urine samples had detectable JCPyV viral load, ranging from 4,500-427,000 copies/mL. All of these samples derived from patients with high antibody index values (>1.5).

Conclusions

The gut is either not the relevant reservoir for PML-associated JCPyV, or stool samples taken at a single occasion are not appropriate to test the hypothesis of JCPyV infection of the gut. As in our cohort the proportion of patients with detectable JCPyV DNA in urine was comparably low, further studies are ongoing validating our results, and improving sensitivity of the JCPyV PCR protocol from stool specimens.

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Presenter Of 1 Presentation

Disease Modifying Therapies – Mechanism of Action Poster Presentation

P0287 - Alemtuzumab induces changes in the innate immune system in patients with relapsing-remitting multiple sclerosis (ID 722)

Speakers
Presentation Number
P0287
Presentation Topic
Disease Modifying Therapies – Mechanism of Action

Abstract

Background

Alemtuzumab is a humanized monoclonal antibody specific for CD52 and has been shown to be an efficient treatment for patients with relapsing-remitting multiple sclerosis (RRMS). CD52 is present at high expression levels on the surface of B- and T-lymphocytes and at low levels on monocytes and NK-cells. Recent evidence has emerged that the innate immune system might also undergo reorganization contributing to the long-lasting immunomodulatory properties of alemtuzumab.

Objectives

To better understand the effect of alemtuzumab on the innate immune system we longitudinally assessed the function of innate immune cells in a cohort of alemtuzumab treated RRMS patients. We particularly focused on distinguished monocyte and macrophage phenotypes to identify specific cellular activational patterns that are modulated during alemtuzumab treatment.

Methods

Peripheral mononuclear blood cells (PBMCs) and plasma were collected from RRMS patients before and every two months after alemtuzumab treatment for 12 months. PBMC surface marker (CD14, CD16, CD23, CD206, CD163, CD86, CCR7, HLA-DR) were assessed by flow cytometry. Monocyte function (phagocytosis of latex beads, ROS production) was examined by in vivo assays. Plasma cytokine levels were analyzed using ELISA.

Results

We observed an increase in the expression of anti-inflammatory surface markers such as CD206 and CD23 on the overall monocyte population. While the distribution of different monocyte phenotypes (classical, intermediate, and non-classical monocytes) did not change significantly after alemtuzumab treatment, several surface marker expressions within the individual phenotypes showed alterations. The CD16+ intermediate and non-classical monocytes showed an increase in anti-inflammatory CD23+, whereas the CD16- population displayed an elevation of pro-inflammatory CCR7 and CD86, 2 months post alemtuzumab treatment and a return to baseline levels later on. Furthermore, CD163+ monocytes, showing phagocytic activity were increased 6 months post-treatment and were still slightly elevated after 12 months, while phagocytosing B-cells showed an increase 12 months post alemtuzumab treatment

Conclusions

Alemtuzumab treatment goes along with complex alterations of the immune system including innate immunity mechanisms. In the peripheral blood compartment, PBMC display an increase in phagocytotic activity.

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