The humoral immune response after thermal injury: an experimental model.
BACKGROUND
Severe thermal injury is associated with major alterations in cell-mediated immunity. Because most B-cell responses are regulated or critically dependent on T-cell help, it is not surprising that many studies have also shown a variety of defects in humoral immunity after thermal injury. However, the nature of the relationship between the in vitro ability to produce antibody and subsequent in vivo responses remains unclear.


METHODS
With a murine model of thermal injury, the primary and secondary humoral immune response to tetanus toxoid (TT) was examined during a 6-week period after sham burn or burn injury. Serum anti-TT titers and the numbers of anti-TT-secreting splenocytes were determined.


RESULTS
Splenocytes from burned animals displayed normal or decreased TT-specific immunoglobulin (Ig) M plaque formation. In contrast, however, IgG plaque formation was persistently increased for up to 6 weeks after thermal injury, suggesting a switch from IgM to IgG antibody production. Conversely serum titers of TT-specific IgG antibody were persistently lower in burn, compared with sham groups. Changes in serum immunoglobulin levels did not account for this marked discrepancy between enhanced in vitro IgG plaque formation but impaired in vivo levels of TT antibody.


CONCLUSIONS
The data suggest that thermal injury is associated with a diminished ability to propagate and maintain a normal IgG antibody response, despite the presence of normal or increased numbers of antigen-specific B cells.
Molloy
R G
RG
Department of Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115.
Nestor
M
M
Collins
K H
KH
Holzheimer
R G
RG
Mannick
J A
JA
Rodrick
M L
ML
D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis* / Q000097:blood; D001402:B-Lymphocytes / Q000276:immunology; D002056:Burns / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005779:Immunodiffusion; D007074:Immunoglobulin G / Q000096:biosynthesis / Q000097:blood; D007075:Immunoglobulin M / Q000096:biosynthesis / Q000097:blood; D008297:Male; D051379:Mice; D008805:Mice, Inbred A; D013745:Tetanus Toxoid / Q000276:immunology
D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D013745:Tetanus Toxoid