Particular features of humoral immunity in patients with acute brain concussion

Traumatic brain injury (TBI) is one of the most common neurological disorders in the world. Meanwhile, usage of neuroimaging methods does not allow precise assessment of its severity and clinical prognosis. This predetermines for searching new techniques of differential diagnosis of the TBI severity and predicting the risk of consequences. Currently, many authors have shown an association between disorders of the immune system manifesting as a decrease in general immune status, and development of cellular/humoral neurosensitization with progredient outcome of the brain injury. At the same time, the role of humoral mechanisms in pathogenesis of TBI, in particular, brain commotion, is less studied in comparison with cell-mediated mechanisms, thus suggesting a need to studying the role of activation or, vice versa, anergy of the humoral immunity in mild traumatic brain injury. The aim of this work was to study characteristics of B-lymphocyte subpopulations in peripheral blood of the patients with brain concussion (n = 22). Peripheral blood samples obtained from 52 apparently healthy volunteers served as controls. The diagnosis was made in accordance with established international criteria. In this case, the exclusion criterion were as follows: severe concomitant organ damage or somatic pathologies, as well as presence of intoxication. General examination included the collection of complaints, medical history, assessment of the somatic and neurological status. B-lymphocytes were determined using multicolor flow cytometry based on two approaches: IgD/CD38 expression (“Bm1-Bm5” classification), and IgD/CD27. We have found that the relative number of naïve Bm1 (IgD+CD38-) was significantly higher in patients with brain concussion than in conventionally healthy individuals (p < 0.001). The relative content of activated naive Bm2-cells (IgD+CD38+) was significantly lower in the group of TBI patients than in controls (p < 0.05). The number of naive cells (IgD+CD27-) was also significantly reduced in the brain concussion group compared to the control group. The data obtained indicate a possible significant role of B-cell immune response in pathogenesis of clinical course following the brain concussion, thus enabling assessment of possible features of humoral immune response.