Title:Evaluation of Specific Immune Responses to BoNT/A and Tetanus Toxoid in Patients Undergoing Treatment for Neurologic Disorders
VOLUME: 12 ISSUE: 3
Author(s):Zaharenia Vlata, Aristidis Tsatsakis, Minas Tzagournissakis and Elias Krambovitis
Affiliation:Department of Veterinary Medicine, School of Health Sciences, University of Thessaly, 224 Trikalon St, Karditsa 43100, Thessaly, Greece.
Keywords:Antibody assay, botulinum neurotoxin (A), PBMC proliferation, tetanus neurotoxin, BoNT/A, anti-tetanus antibody levels, Pharmingen, Clostridium botulinum, neurotoxins, immunostimulation.
Abstract:Botulinum neurotoxins (BoNTs) are used in the treatment of many neurological disorders. The primary
structure of BoNTs shows a high degree of homology with the tetanus neurotoxin, the toxoid of which is used as a
vaccine. Because of the potential cross-reactivity between these toxins, we investigated the effects of Botulinum
neurotoxin A (BoNT/A) and tetanus toxoid on peripheral blood mononuclear cells (PBMC) and the corresponding serum
antibody levels, in twenty patients who had been treated with BoNT/A. We observed very low PBMC immunostimulation
by BoNT/A at the tested dose (15 units/ml), as demonstrated by the low lymphocyte proliferation, and the absence of
detectable antibodies cross-reacting with tetanus. However, exposure of PBMC from tetanus-sensitized patients to both
neurotoxins showed that BoNT/A exerted a co stimulatory effect on tetanus-stimulated cells. Interestingly, in flow
cytometry analysis, BoNT/A seemed to also alter the ratio of naïve (CD45RA) : memory/effector (CD45RO) T
lymphocyte subsets, in favour of CD45RO. These preliminary data give a new insight on the potential immune crossreactivity
between the two antigens. In view of the wide use of both neurotoxins, these immunotoxic effects merit a more
detailed investigation.