脾切除对肺内细胞清除和移位的影响

目的：探讨脾切除对肺内细菌清除及移位的影响，同时观察自体脾组织移植的应用效果，方法：将Ｗｉｓｔａｒ大鼠９０只随机分为假手术组、脾切除级玫半脾移植组，采用肺炎球菌悬雾化吸入方法攻埚动物，观察肺组织学病变，肺内细菌清除和移位状况。结果：脾切除组动物肺组织严重充血肿胀，炎性细胞浸润少，肺内细菌清除功能降低，细菌向肺门淋巴结移位和侵入血流加快，与假手术组比较有显著性差异，但半脾移植组动物能基本恢复对肺炎球     

不同量自体脾组织移植抗肺炎球菌感染的研究

采用大鼠进行不同量脾组织网膜内移植，术后６月检测有关抗感染指标，结果显示气管内感染肺炎球菌后，４０％，６０％，８０％脾移植组和假手术组的存活率明显高于脾切除组，血中肺炎球菌廓清率在脾切除组中明显下降，而在各移植组则接近正常，结果表明，自体脾组织移植有一定上的抗感染能力，脾组织移植量以４０％～６０％为宜。     

脾血流在清除肺炎球菌中的作用

本动物实验旨在研究脾脏对肺炎球菌的清除率,确定自血中清除细菌时脾血流量与脾组织量之间的关系,从而探索借维持脾动脉血流以保存损伤脾的合理性。将17只兔分为5组:第Ⅰ,正常组,仅作剖腹探查术,作为对照组;第Ⅱ,脾动脉结扎组;第Ⅲ,自体移植组,先切除脾脏,切脾后作自体移植;第Ⅳ,半脾切除组;第Ⅴ,全脾切除组。除Ⅰ组的脾血流和脾组织量为正常外,其它四组均有不同程度的减少。上述动物在正常条件下饲养三个月后,又按测定脾血流脾组织量和测定肺炎球菌自血流中的清除再分成二组,共10个小组。结果如下:     

脾切除和自体脾组织移植对肺吞噬功能的影响

本实验采用放射性Ⅰ标记的脂类乳剂测定肝、脾、肺的放射性活度和吞噬指数，并结合病理组织学检查动点观察脾切除和脾移植对肺吞噬功能的影响，结果发现，脾切除组动物肝的吞噬功能受到抑制，啼的吞噬功能代偿性增强，自体移植脾组织能部分恢复肺的吞噬功能。     

隔离小肠段,网膜内自体脾组织移植的研究

目的:观察隔离小肠段、网膜内自体脾移植的抗感染能力并比较移植脾与原脾差异.方法:将24只雄性大耳白兔分为四组:Ⅰ、假手术组;Ⅱ、空肠内移植组;Ⅲ、网膜内移植组;Ⅳ、脾切除组.5个月后用1.4×10~(12)CFU/LⅢ型肺炎球菌静脉攻击.光镜、电镜观察,IBAS图象分析仪测红髓、白髓、边缘带面积.结果:移植脾不能有效抵抗脾切除后感染,组织学结构发生了质变.     

严重外伤性脾破裂切除加自体脾移植的临床疗效及其对免疫状态的影响

目的 探讨严重外伤性脾破裂切除加自体脾移植的方法、临床疗效及其对免疫状态的影响.方法选取严重外伤性脾破裂患者46例,其中行单纯脾切除的26例设为对照组,行脾切除加自体脾移植术的20例设为观察组.比较两组患者的围手术期效果,术后14、28天的免疫功能,术后每周监测移植脾脏组织存活情况.结果观察组脾切除后切口感染发生率少于对照组（P＜0.05）;观察组术后28天体液免疫、细胞免疫指标均高于术后14天时水平（P＜0.05）;术后28天,观察组体液免疫、细胞免疫指标均高于对照组相应水平（P＜0.05）.术后2周时,除1例有较模糊影像外,其余患者移植脾脏组织均可见到有较浓密、清晰的移植脾片影,经专家会诊表明移植脾片已成活.结论严重外伤性脾破裂切除加自体脾移植容易操作,移植脾组织片易于成活,恢复了患者的免疫功能状态,术后患者感染率低,并发症少,效果满意,对具备适应症者的手术治疗具有一定的借鉴意义.     

自体脾腹膜后移植在创伤性脾破裂中的临床应用

目的探讨自体脾组织移植在治疗创伤性脾破裂的应用.方法对本组于2000年1月至2005年4月22例脾破裂行全脾切除后,再行自体脾组织腹膜后移植术.通过检测外周血IgM、IgA、IgG水平和B超,CT、99mTc扫描来观察移植脾片成活和吞噬功能恢复情况.结果术后随访均显示移植脾存活良好,脾功能满意.结论自体脾组织移植可作为严重脾外伤全脾切除术后保留脾功能的一个重要有效手段.     

自体移植脾组织VEGF、KDR表达与血管再生的实验研究

目的 研究自体移植脾组织血管再生及VEGF、KDR表达规律，阐明VEGF、KDR对移植脾组织血管再生的调控作用，为脾脏外科临床及实验研究提供理论依据。方法 健康Wistar大鼠70只，体重100—120g，随机分为7组，每组10只中又设脾切除自体脾移植组5只，假手术组5只，分别于术后7，14，30，60，90，120，180d进行：(1)自体移植脾组织病理学检测；(2)大鼠行主动脉插管灌注墨汁，光镜观测再生血管并采用图像分析测定其密度；(3)免疫组化抗VEGF、KDR抗体染色，图像分析定量，阐明其表达规律及与血管再生的关系。结果 (1)自体脾组织移植术后7d即有血管从大网膜向脾组织内伸展，移植脾组织内血管密度逐渐增大，至术后180d血管再生接近正常；(2)自体脾组织移植术后7d、14d，VEGF、KDR阳性染色细胞密度迅速升高，术后60d达高峰，以后逐渐降低，至术后180d VEGF、KDR阳性染色细胞密度趋向正常。结论 自体脾组织大网膜内移植术是简便有效的脾移植方法；移植脾组织新生血管由大网膜再生而来；术后移植脾组织内VEGF、KDR表达量升高，促进血管形成，血管再生完成后恢复正常水平。     

自体脾移植联合食管横断吻合术治疗肝硬化门静脉高压症

目的 探讨腹膜后自体脾移植联合食管横断吻合术治疗肝硬化门静脉高压症的临床疗效.方法 将2003年1月至2006年12月收治的36例肝硬化门静脉高压症患者随机分为自体脾移植组(n=18)和脾切除组(n=18),自体脾移植组接受脾切除、食管横断吻合及自体脾移植术,脾切除组接受脾切除、食管横断吻合术.于术前及术后2～6个月定期观察两组患者的一般情况、行脾脏放射性核素扫描,同时检测肝功能、血清促吞噬素(Tuftsin)及IgM水平,并行组间及手术前后比较分析.结果 自体脾移植组患者术后2个月血清Tuftsin和IgM水平与术前比较无明显差异(P0.05),而脾切除组患者术后2个月血清Tuftsin和IgM水平较术前明显降低(P<0.05);自体脾移植术对患者肝功能无明显影响;术后2个月放射性核素扫描证实移植脾于腹膜后存活.结论 自体脾移植对保留机体脾脏免疫功能具有重要价值,腹膜后自体脾移植联合食管横断吻合术治疗肝硬化门静脉高压症的临床效果确切,值得推广应用.     

脾组织移植保留脾损伤患者脾功能的实验研究

自体脾组织移植已成为保留严重脾损伤患者脾功能的措施之一,但移植牌组织的功能如何,对机体究竟有多大影响,尚未定论。提高自体移植脾组织的功能已成为人们普遍关心的问题。因此,本文研究了动物自体移植脾组织的结构与功能;初步探索评价了促进自体移植脾组织生长的措施。     

Pulmonary antipneumococcal defenses after hemisplenectomy

Conservative splenic surgery such as partial splenectomy is advocated for splenic injuries, since splenectomy predisposes individuals to overwhelming sepsis with encapsulated organisms, of which Streptococcus pneumoniae is the most frequently isolated. The respiratory route is argued to be the most likely portal of entry of pneumococci; however, little data exist on the interaction of the spleen and pulmonary defense mechanisms against pneumococcal invasion. We studied the effect of splenectomy, 50% splenectomy (hemisplenectomy), 25% splenectomy, and sham operation on in vivo clearance of live pneumococci from the lungs of male CD-1 mice following an aerosol challenge of pneumococci. Splenectomy impaired pneumococcal clearance from mouse lung pairs and allowed for increased translocation of live pneumococci to tracheobronchial lymph nodes compared to sham-operated controls. Preservation of splenic mass by partial splenectomy improved lung clearance and allowed for fewer bacteria to be cultured from tracheobronchial lymph nodes compared to splenectomized animals. Clearance of live pneumococci from the lungs and survival were directly proportional to the amount of splenic tissue remaining. Splenic factors probably exist which regulate reticuloendothelial cell function throughout the host. Maintaining adequate splenic mass, therefore, is an important consideration when operating for splenic trauma.     

Optimal site and amount of splenic tissue for autotransplantation.

Clinical and basic studies have documented a high susceptibility to pneumococcal infection in asplenic humans and animals. It has been suggested that autotransplantation of splenic tissue might be a method of providing host resistance when total splenectomy is necessary. However, the effect of splenic autograft has remained controversial. This study was performed to evaluate the most effective site and amount of splenic autograft using rats. Rats were divided into five groups for the purpose of determining the site of splenic autotransplantation: splenectomy, sham operation, implantation into the omental pouch, intraperitoneal implantation, and intramuscular implantation. For determining the amount for autotransplantation, the rats were divided into seven groups: splenectomy, sham operation, and implantations of 25, 50, 100, 200, or 300 mg of splenic tissue. All animals were challenged with Streptococcus pneumoniae type 6, 16 weeks after surgery. Howell-Jolly bodies appeared postsplenectomy, but disappeared in the implanted rats 16 weeks after the operation. Histologically, the implanted tissue was indistinguishable from that of a normal spleen. Pneumococcal clearance from the bloodstream and survival rate were significantly higher in rats implanted in the omental pouch as compared with splenectomized rats. Intraperitoneal and intramuscular implanted rats did not show a significant difference from the splenectomized rats. More than 50% of splenic tissue for autograft showed a significant increase in pneumococcal clearance and survival rate as compared with that of splenectomized rats. It was suggested that the most effective site of autotransplantation is the omental pouch and approximately 50% of the whole spleen would be necessary for prevention from sepsis.     

Improved survival with splenic autotransplantation and fibronectin therapy following endotoxin administration in rats

The risk of overwhelming infections is greatly increased after splenectomy. In this experimental study in rats, we investigated whether the administration of fibronectinrich cryoprecipitate can improve the survival rate of splenectomized autotransplanted rats subjected to an intravenous challenge with endotoxin. Inbred Lewis rats were divided into four groups: A, splenectomy; B, splenectomy + splenic autotransplantation; C, splenectomy, splenic autotransplantation + fibronectin treatment, and D, sham. Five months after surgery, rats were challenged intravenously with Escherichia coli endotoxin. Immunoglobulin (IgG, IgM, IgA), complement and fibronectin levels were measured before surgery and endotoxin challenge, and 48 h after endotoxin challenge. The survival rate of splenectomized rats was not significantly improved by autotransplantation of splenic tissue, but was significantly (p less than 0.05) improved by autotransplantation and fibronectin treatment. The levels of fibronectin, immunoglobulins and/or complements were significantly decreased after endotoxin challenge in control and in autotransplanted fibronectin-treated rats. The survival improvement of autotransplanted rats treated by fibronectin is probably due to increased endotoxin phagocytosis and clearance.     

Comparison of omental splenic autotransplant to partial splenectomy. Protective effect against septic death

The possible benefit of either partial splenectomy or splenic autotransplantation as protection against post-splenectomy sepsis was investigated. Sprague-Dawley rats were challenged with intravenous Streptococcus pneumoniae and the incidence of bacteremia and mortality were recorded. Animals were divided into four groups based upon the amount of splenic tissue conserved: total splenectomy (0%), partial splenectomy (62%), splenic autotransplantation (27%), or sham celiotomy (100%). A statistically significant (P 0.05) decrease in the incidence of septic death was seen in comparing the total splenectomized animals (63%) to the autotransplant group (27%), the partial splenectomy (4%) and the control group (4%). This diminishing mortality is inversely proportional to the amount of splenic remnant in the respective groups. There was a similar, parallel relationship in the incidence of Streptococcus pneumoniae bacteremia. Thus, the greater the amount of remaining splenic tissue, the lower the incidence of bacteremia and subsequent mortality, implying the preservation of immunologic function with splenic conservation.     

Intraportal splenic autotransplantation in rats: Feasibility and effectiveness

This experiment was designed to see whether or not normal host resistance to infection could be reestablished in splenectomized animals by intraportal autotransplantation of homogenized splenic tissue. Part I studied the feasibility of the technique. Within 1 hr of splenectomy, 16 adult Lewis rats received an intraportal injection of autogenous splenic tissue which had been passed through a 500-μm screen. Five rats died acutely from hemorrhage at the site of injection. The others tolerated the infusion well, both acutely and chronically. The animals developed only transient elevations in liver enzymes; chronic portal hypertension did not occur. Histologically, splenic tissue could be demonstrated within terminal portal venules. Part II assessed the effectiveness of intraportal splenic autotransplantation. Eight to twelve months after splenectomy, autotransplantation, or sham operation, 103 Sprague-Dawley rats were challenged with intravenous boluses of 10⁵ to 10⁸ pneumococci. Mortality was 91% for splenectomized animals, 88% for animals bearing autotransplants, and 59% for controls. Thus intraportal splenic autotransplantation is technically feasible in rats. The grafts are well tolerated by the liver, and splenic tissue is preserved in intimate contact with the blood stream. Even after 8 to 12 months, however, such autografts are not capable of providing normal protection against massive pneumococcemia.     

Serum antibody responses to pneumococcal vaccine after splenic autotransplantation

Immunization with pneumococcal capsular polysaccharide vaccines is advocated after splenectomy; however, experimental and clinical data suggest an impaired antibody response in splenectomized individuals. This study examined the value of splenic autotransplantation at various sites in augmenting the antibody response to Type III pneumococcal capsular polysaccharide in mice immunized 3 months after operation. Splenectomy resulted in impaired antibody responses compared to sham-operated mice (p less than 0.001) using an enzyme-linked immunosorbent assay. Mice with intraperitoneal splenic autotransplants, but not mice with subcutaneous or intramuscular transplants, had greater antibody responses compared to splenectomized mice (p less than 0.05). Antibody responses were elevated only in mice autotransplanted with 50% or more of the original splenic mass. Since autotransplantation of splenic tissue augments the antibody response to pneumococcal capsular polysaccharides, the combination of splenic autotransplantation and pneumococcal vaccination may confer more protection than either modality alone in individuals who must undergo splenectomy.     

Influence of splenectomy, partial splenectomy and splenic artery ligation on E. coli sepsis in rats

Male Sprague-Dawley rats were allocated to four groups--sham operation, partial splenectomy, splenic artery ligation or total splenectomy, and 4 weeks after the operation 3 x 10(8) colony-forming units of Escherichia coli were injected intraperitoneally. Among the splenectomized rats the mortality was significantly (p less than 0.02) increased compared with the controls, while both partial splenectomy and splenic artery ligation did not influence survival. Blood clearance and organ (liver, spleen and lungs) uptake of intravenously injected, radiolabelled, heat-killed E. coli were determined 1 hour after the intraperitoneal challenge. Splenectomy caused a significant decrease in blood clearance. Splenic uptake of radiolabelled E. coli was significantly reduced following partial splenectomy and splenic artery ligation. The splenic operations increased hepatic uptake expressed per gram tissue. Splenectomy thus resulted in reduced blood clearance and increased mortality in Gram-negative sepsis, while the reduced splenic uptake following partial splenectomy or splenic artery ligation did not influence blood clearance of E. coli or mortality.     

Penicillin and natural immunity protect against postsplenectomy sepsis

Prophylactic penicillin, splenic autotransplantation, and immunization using pneumococcal vaccine have all been shown to reduce the incidence and mortality of postsplenectomy sepsis. However, little is known regarding the effect of penicillin in established infection or the effect of prior infection in either asplenic controls or animals with autotransplanted splenic tissue. An animal model with bacterial introduction via the lungs was used to investigate the effect of penicillin, splenic autotransplantation, and previous exposure to the infecting organism on the mortality of postsplenectomy sepsis. One hundred fifty-nine rats underwent either sham celiotomy, intraperitoneal splenic autotransplantation, or splenectomy. Twelve weeks postoperatively all animals were challenged using Streptococcus pneumoniae delivered transtracheally. Half of each group received procaine penicillin by intramuscular injection for 5 days beginning 24 hr post bacterial inoculation and mortality was observed. Eight weeks later surviving rats that had received penicillin were reinoculated with the same organism and mortality was again observed. Splenic autotransplantation reduced the early mortality in postsplenectomy sepsis. Prior bacterial exposure reduced the mortality in postsplenectomy sepsis, even in splenectomized animals. Treatment with penicillin produced a marked reduction in mortality even when administration was postponed for 24 hr after bacterial inoculation.     

Heterotopic splenic autotransplantation in prevention of overwhelming postsplenectomy infection.

An experimental study was undertaken to evaluate the protective effect of heterotopic splenic autotransplantation in weanling rats. Rats were divided into three experimental groups: splenectomy, control, and splenic autotransplantation. Rats were challenged with i.v. type I pneumococcus. Bacterial bloodstream clearance and survival were determined. Splenic bacterial uptake was measured by determining the isotopic activity of technetium-99m-labeled pneumococci. Autoradiographs and material stained with hematoxylin and eosin and Gram strains were examined for histologic features. All autografts survived and were histologically compatible with normal splenic tissue. Bloodstream clearance of pneumococci was significantly greater in rats with splenic autotransplantation. Splenic autografts had 10 to 30 times greater uptake of pneumocci than did the liver. Rats with autotransplantation had a prolonged survival time. Heterotopic splenic autotransplantation may prove to be an important adjunctive surgical measure in the treatment of children undergoing splenectomy.     

Decreased phagocytic capacity of autotransplanted splenic tissue

Background: Asplenic patients have an increased risk of infections. Operations such as autotransplantation have been proposed to restore functional splenic tissue after splenectomy, but the protective value of this tissue is unclear. Immune responses such as production of antibody remain impaired in humans and animals even when such tissue is present, and clearance of particles from the blood is reported to be less efficient than by normal spleen tissue. The present study investigated the phagocytic capacity of cells in the regenerated tissue in vitro, free of the confounding effects of hepatic clearance. Methods: Single cell suspensions were prepared from splenic tissue from rats 6 months after splenic autotransplantation or sham operation. Phagocytosis of killed, fluorescein‐labelled bacteria was measured by flow cytometry. Results: Autotransplanted tissue contained fewer phagocytic cells than normal tissue, and these cells phagocytosed less per cell. Phagocytosis by spleen cells was dependent on heat‐labile opsonic factors. Conclusions: Autotransplanted splenic tissue does not restore the phagocytic capacity lost following splenectomy.