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GROUP LEADER : EL FAR Oussama

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RESEARCH TOPIC :

We have two principal objectives:

• to carry out serological assays for the diagnosis of autoimmune neurological disease

• to carry out the detection of the enzymatic activity of botulinum neurotoxins A, B and E in contaminated samples.

 



Anti-Cav2 calcium channel antibodies.

In Lambert-Eaton myasthenic syndrome (LEMS), patients produce antibodies against Cav2-type voltage-dependent calcium channels (VGCC). These antibodies reduce calcium-influx into nerve terminals in the peripheral nervous system and thus perturb neurotransmitter release, which leads to muscular weakness and dysfunction of the autonomic nervous system.
In 60 – 70% of cases LEMS is paraneoplastic and the immune response is initiated by a lung tumor. Thus diagnosis of LEMS can lead to early detection of cancer. We routinely perform two serological assays to titer anti-Cav2.1 (P/Q-type) and anti-Cav2.2 (N-type) antibodies.Cliquez pour agrandir pdf_JMG.jpg (1 Ko)


For further information contact:
Nicole Moutot
/ EL FAR Oussama




Anti-Kv1 potassium channel antibodies (This activity is curently disrupted).

Circulating antibodies against voltage-dependent Kv1-type potassium channels (VGKC) were initially described in acquired neuromyotonia (Isaac’s syndrome). In this disease of the peripheral nervous system, spontaneous motoneurone discharge leads to myokimia. Anti-Kv1 potassium channel antibodies have also been identified in limbic encephalitis, an autoimmune disease affecting the central nervous system with symptoms such as amnesia, insomnia, hallucinations, seizures and psychosis.
Limbic encephalitis was initially considered to be principally paraneoplastic in origin. However the presence of anti- Kv1 antibodies is now thought to point to a form of limbic encephalitis without associated cancer. In this case immunosuppressive therapy often reduces central symptoms including amnesia. Some patients display both peripheral and central symptoms, a condition known as Morvan syndrome. We routinely perform a serological assay to titer antibodies against Kv1.1, 1.2 and 1.6 channels and the associated protein LGI1.Cliquez pour agrandir pdf_JMG.jpg (1 Ko)


For further information contact: Nicole Moutot / EL FAR Oussama


Botulinum neurotoxins
The clostridial neurotoxins include tetanus toxin (TeNT) and seven botulinum neurotoxin serotypes (BoNT/ A to G). They induce two severe diseases: tetanus and botulism. BoNT/A and B are also used as therapeutic and cosmetic agents. Using Surface Plasmon Resonance (SPR) technology, we have developed biosensors to assay botulinum and tetanus toxins in complex mixtures (serum and food samples…..) with high sensitivity (Ferracci et al 2011). The biosensors use substrates and monoclonal antibodies that we have generated, which recognize the specific proteolytic signature of each neurotoxin. We are seeking partners to further develop these approaches.


For further information contact:
Christian Léveque


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