Preserved granulocyte formation and function, as well as bone marrow innervation, in subjects with complete spinal cord injury

Abstract

SummaryPatients with a spinal cord injury are at risk of infections and is partly attributed to immobilization. Their lymphocyte-mediated immunity is impaired and the growth of blood progenitor cells is reduced. An adequate immune response depends on granulocytes being mobilized rapidly and activated properly, at the inflammatory site. Possibly this requires a coordinated interaction between the autonomous nervous system and cells within the haematopoietic bone marrow. Granulocyte function in the spinal cord injured has not been evaluated. Although there is evidence that the bone marrow in rodents is innervated, it is uncertain whether human bone marrow is similarly affected. Microscopy and immunolabelling followed by flow cytometry, showed that blood and bone marrow counts of leucocyte subsets were similar in paraplegic, tetraplegic and control subjects (P > 0AE05). Neutrophilic migration and oxygen consumption, as well as eosinophil activation, assayed as release of eosinophilic cationic protein or CD69 expression, were not altered after spinal cord injury (P > 0AE05). Cryostat sections of human bone marrow biopsies stained positive with glyoxylic acid, indicating the presence of catecholamine-containing nerves in both the patients and the controls. We conclude that terminal differentiation and formation of granulocytes, as well as their functional capacity, do not depend appreciably on supraspinal nervous regulation.

Chronic Spinal Cord Injury Impairs Primary Antibody Responses but Spares Existing Humoral Immunity in Mice

“…However, B lymphopoiesis recovered within 4 weeks despite continued elevation of corticosterone in chronically injured mice. These observations are consistent with those in chronic SCI patients, who have normal numbers of bone marrow lymphocytes despite elevated stress hormones (41, 42). Accordingly, transiently reduced B lymphopoiesis likely reflects additional or alternative mechanisms.…”

Hormonal And Immunological Changes in Mice after Spinal Cord Injury

“…Surprisingly though, little is known about changes of blood and bone marrow cell numbers after SCI, despite the fact that immune functions are often impaired and that infection is a major cause of death after SCI ( al., 1992; Iverson et al, 2004). The present results clearly showed significant decreases of total leukocytes with lymphocytes and eosinophils decreased at all time points post-Tx in both blood and bone marrow.…”

Altered innate immunity following spinal cord injury

“…13,14 Spinal cord injury in humans presents a unique opportunity to study possible early release of progenitors from the bone marrow in subjects with injury to the central nervous system. 15 Iversen et al, 15,16 after two studies, concluded that terminal differentiation of immune cells did not require supraspinal control; however, more investigation was needed to fully explore this possibility.…”