Serum TGF-beta in thermally injured rats.
A severe thermal injury is commonly associated with immune suppression and increased susceptibility to sepsis, frequently leading to multiple organ failure. Transforming growth factor-beta (TGF-beta) is a potent immunosuppressive cytokine involved in complications associated with major trauma. Interleukin- 4 (IL-4) is thought to synergize the immunosuppressive activity of TGF-beta by promoting naive lymphocytes to differentiate and generate TGF-beta secreting cells. This study examines the alterations in serum levels of TGF-beta and IL-4 after a thermal injury. Male Sprague-Dawley rats (300-400 g) were anesthetized and received a 50% total body surface area full-thickness scald burn followed by fluid resuscitation and analgesia. Control rats were given the same treatment, but were immersed in water at room temperature. Rats were sacrificed from 1 h to 8 days after injury. Blood samples were collected aseptically from the inferior caval vein. Serum levels of TGF-beta and IL-4 were measured by enzyme linked immunosorbent assay. Rats in the control and thermal injury groups showed similar increases in serum TGF-beta 1 h after injury. A progressive increase in serum TGF-beta was observed in burned animals compared to control animals starting on day 3 and continued through day 8 (P < 0.01). Serum IL-4 levels in control and thermally injured animals remained undetectable (< 15.6 pg/mL) throughout the experiment. Thermal injury induces a significant increase in serum TGF-beta, which may contribute to post-burn immunosuppression with an increased susceptibility to sepsis.
Varedi
M
M
Department of Surgery and Shriners Hospital for Children, University of Texas Medical Branch, Galveston, Texas 77555, USA.
Jeschke
M G
MG
Englander
E W
EW
Herndon
D N
DN
Barrow
R E
RE
D000818:Animals; D015415:Biomarkers / Q000097:blood; D002056:Burns / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D016212:Transforming Growth Factor beta / Q000097:blood*
D015415:Biomarkers; D016212:Transforming Growth Factor beta