Alteration of Th17 and Treg cells in dogs in the acute phase of painful intervertebral disc herniation

Intervertebral disc herniation (IVDH) can be associated with neuropathic
and inflammatory pain. Neuropathic pain has been suggested to be
influenced by the proinflammatory immune response and experimentally
and in human studies by alteration of Th17 and Treg cells. In the current
study, we hypothesized that the Th17/Treg balance may be altered in
dogs with painful IVDH when compared with non-painful IVDH. Pain
was evaluated subjectively during the neurological examination in
52 dogs. The absolute numbers of Th17 and FOXP3 + Treg cells were
quantified using a multicolor flow cytometry in blood samples in the
acute phase of the disease before surgical treatment. Th17, Treg cells
and Th17/Treg ratio were compared statistically between patients with
painful (n= 40) and non-painful (n= 12) IVDH, and between ambulatory
(n= 16) and non-ambulatory (n= 24) painful IVDH. There was no statistically
significant difference between Tcell values of painful and nonpainful
dogs (p>0.05). Although the mean values of Th17, Treg and
310 ABSTRACT
Th17/Treg ratio of the non-ambulatory painful IVDH patients increased
compared to ambulatory ones, this increase was found statistically insignificant.
Rising Th17 cell numbers were accompanied with increased
values of Treg cells. The results of this study show that alteration of T
cell subsets might be related with the severity of the inflammation rather
than pain in the acute phase of IVDH.