Immune function of the upper splenic remnant supplied by short gastric vessels.
OBJECTIVE
To study the immune function of the upper third of the spleen supplied by short gastric vessels after two thirds partial splenectomy.


METHODS
Experimental study.


METHODS
Teaching hospital, Turkey.


METHODS
Sixty Wistar-albino rats, 20 in each group.


METHODS
Control = sham laparotomy; partial splenectomy = the upper third of the spleen supplied by short gastric vessels was preserved after two thirds partial splenectomy and dividing the main vascular supply; and total splenectomy. At the end of the sixth week postoperatively, antigenic stimulation was induced with an injection of pneumococcal suspension in 10 animals from each group. 0.5 ml of diluted Indian ink was injected into the aorta.


METHODS
Histological architecture of splenic tissue, and changes in the white pulp after antigenic stimulus. Bacteriological analysis with aerobic blood culture. Phagocytic activity as counted by Indian-ink-laden macrophages. The ability to produce antibodies as measured by serum IgM concentrations.


RESULTS
Histological architecture of splenic tissue was normal. Germinal centres (p = 0.02), lymphoid follicles (p = 0.09), and their ratio (p = 0.0006) in the white pulp of the splenic remnant was significantly increased after antigenic stimulus compared with normal spleen. Significantly more animals without spleens developed bacteraemia (p = 0.02). Phagocytic activity of the upper splenic remnant was 89% that of normal spleen. Serum IgM concentrations without antigenic stimulus were 144, 138.2 (p = 0.6), and 86.2 (p < 0.001) mg/L; and with antigenic stimulus 263, 201.7 (p < 0.0001), and 98.1 (p < 0.0001) mg/L in groups 1, 2, and 3, respectively. The increase in serum IgM concentrations as a response to antigen was significant in the control (p < 0.0001) and in the partial splenectomy group (p < 0.0001), but not in the splenectomy group (p = 0.1).


CONCLUSIONS
After reduction of its volume, the upper splenic remnant remained adequately supplied by the short gastric vessels. The upper part of the spleen preserved its normal histological architecture, had considerable phagocytic activity, possessed the ability to produce antibodies, and created a satisfactory immune response to antigenic stimulus. In rats, a considerable volume of functional and well perfused splenic tissue is preserved even after dividing the main vessels.
Gürleyik
E
E
Department of Surgery, Haydarpasa Numune Hospital, Istanbul, Turkey.
Gürleyik
G
G
Ozkutlu
D
D
D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D000942:Antigens, Bacterial / Q000276:immunology; D010587:Phagocytosis; D051381:Rats; D017208:Rats, Wistar; D013154:Spleen / Q000098:blood supply* / Q000276:immunology*; D013156:Splenectomy; D013296:Streptococcus pneumoniae / Q000276:immunology
D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial