Altered splenic B cell subset development in mice lacking phosphoinositide 3-kinase p85alpha

The signaling enzyme phosphoinositide 3-kinase (PI3K) is activated following B cell receptor (BCR) engagement and by many other receptors on B lymphocytes. Mice lacking p85alpha, the predominant PI3K regulatory isoform, exhibit defects in B cell development and activation that are grossly similar to those found in mice lacking Bruton's tyrosine kinase (Btk) and other critical signaling molecules. However, a detailed analysis of splenic B cell subsets in p85alpha-deficient mice has not been reported. Here we show that these mice are deficient in four major B cell subsets: transitional-1, transitional-2, follicular and marginal zone. These defects are distinct from those observed in Xid mice that express a mutant Btk unable to interact with PI3K lipid products. Moreover, mice with both genetic lesions exhibit even greater impairment in B cell development. Finally, we show that transgenic expression of the anti-apoptotic protein Bcl-2 in p85alpha-deficient mice restores the transitional B cell subsets but not the marginal zone subset, and produces a follicular population with an aberrant phenotype. These findings establish a role for PI3K-p85alpha in differentiation of both follicular and marginal zone B cells, and suggest that these functions are required not solely for the propagation of anti-apoptotic signals.     

妊娠期间脾脏T淋巴细胞的改变与鼠胚着床

应用ＦＩＴＣ标记的Ｌ３Ｔ４及Ｌｙ２单克隆抗体，及流式细胞计细胞分选，对小鼠妊娠期间脾脏Ｔ淋巴细胞亚群进行检测。结果表明，妊娠早期小鼠脾脏ＣＤ８＋淋巴细胞比例减少，在着床时尤为明显。提示脾脏Ｔ淋巴细胞数量和功能变化，参与维持正常妊娠，尤其是参与着床。     

Effects of adrenergic stimulants on the splenic diameter,haemoglobin content and haematocrit in anaesthetized dogs: determination of the adrenoceptor subtype responsible for changes in the splenic diameter

Changes in splenic diameter measured by sonomicrometry in response to various adrenergic stimulants were estimated together with simultaneously measured arterial haemoglobin content (HGB) and haematocrit (HCT) in anaesthetized dogs. Splenic diameter decreased following intravenous injections (i.v.) of adrenaline, noradrenaline and phenylephrine and splenic nerve stimulation associated with increases in arterial HGB and HCT, which were significantly attenuated by prazosin i.v. After prazosin i.v., adrenaline i.v. increased splenic diameter significantly, but noradrenaline i.v. did not. Isoprenaline i.v. increased splenic diameter transiently, followed by a decrease that was abolished by prazosin i.v. During occlusion of splenic arteries and veins, adrenaline i.v. and phenylephrine i.v. did not cause any change in arterial HGB and HCT. Injection to splenic artery (i.a.) of phenylephrine induced a significant decrease in splenic diameter that was attenuated by prazosin i.a. but not by yohimbine i.a. Clonidine i.a. did not change splenic diameter. The present results indicate that splenic contraction, which is mediated through α₁-adrenoceptor activation, causes a significant increase in arterial HGB and HCT.     

二氧化硫吸入对小鼠脾细胞凋亡的诱导作用

目的:探讨二氧化硫大剂量吸入对小鼠脾细胞凋亡和脾脏组织学结构的影响.方法:以不同浓度的二氧化硫分别对小鼠连续染毒7d,用透射电镜法、DNA琼脂糖凝胶电泳法和流式细胞技术观察小鼠脾脏组织学结构和细胞凋亡改变.结果:在二氧化硫染毒组小鼠脾脏的红髓区和白髓区均有典型的脾细胞凋亡发生,在边缘区可见大量核变形淋巴细胞,此外还可见巨噬细胞出现明显的凋亡改变和网状内皮细胞受损.168mg/m3二氧化硫染毒可引起小鼠脾细胞凋亡率增加.结论:大剂量二氧化硫吸入可引起小鼠脾脏超微结构改变,在一定剂量和时间范围内可引起脾细胞凋亡加速,从而对机体的免疫功能造成一定损伤.     

Kinetics of hematopoietic stem cells in the bone marrow of hepatectomized mice

Two thirds of the liver was removed from (CBA×C57BL/6j)F₁ female mice. On the 5th day after the operation a significant increase was observed in the number of endogenous colonies in the spleen of the partially hepatectomized animals. This increase was not connected with a change in the number of stem cells in the bone marrow, for partial hepatectomy at different times after the operation did not affect the number of colony-forming units in the bone marrow.Laboratory of Virology, Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Kraevskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 2, pp. 218–219, February, 1978.     

Lymphokine-activated killer cell function of peripheral blood mononuclear cells, spleen cells and regional lymph node cells in gastric cancer patients.

Lymphokine-activated killer (LAK) cells generated by culture of peripheral blood mononuclear cells (PBMC), spleen cells (SPC) and regional lymph node cells (LNC) with IL-2 for 4 days were examined for their functional capabilities in 29 patients with gastric carcinoma. The cytotoxic activity of LAK cells induced from LNC was significantly lower than that from either PBMC or SPC, although there was no difference between PBMC or SPC. The induction of mRNA of interferon-gamma (IFN-gamma) or tumour necrosis factor-alpha (TNF-alpha) and the production of these cytokines in the non-adherent LAK cells from LNC were also significantly reduced compared with those from PBMC or SPC. Further, the LAK cells from LNC secreted significantly lower levels of these cytokines when stimulated with tumour target, Raji cells, although the production of these cytokines was markedly increased by stimulation with the targets in all three cell populations. Phenotypic analysis of each cell population revealed a decreased proportion of the cells mediating natural killer (NK) activity, including CD16+, CD56+, and CD57+ cells in LNC either before or after culture, although OKIa1+ and CD25+ cells were uniformly increased in all cell populations after culture. Changes in subpopulations of CD4+ and CD8+ cells in LNC were not apparently different from PBMC or SPC. These results indicated the differential reactivity of each lymphocyte population to IL-2 and the reduced LAK cell function of LNC compared with PBMC or SPC in patients with gastric carcinoma.     

Branches of the splenic artery and splenic arterial segments

In 200 adult autopsy specimens, the arterial supply to the pancreas and spleen was studied radiologically and by manual dissection. The splenic artery divided into two or three lobar arteries, which supplied its corresponding lobe; each lobar artery subsequently divided into two to four lobular branches. Six to twelve lobular branches were observed entering the splenic substance at the hilum. Lobar arteries did not anastomose with each other, hence, the lobes of the spleen are also termed segments. The lobules, however, were not found to be independent segments and the arteries of one lobule anastomosed with those of other lobules. The branching pattern of the splenic artery varied from one specimen to another, so much so that a prevailing pattern could not be identified. Polar arteries, particularly to the superior pole, arose quite proximal to the hilum in 51% of cases and were occasionally missed. In 45% of males and 40% of females, the posterior gastric artery arose from about the middle of the splenic artery. The splenic artery was not found to be tortuous in fetuses, newborns, and young children. Tortuosity was seen in only 10% of adults; thus, the characteristic tortuosity of the splenic artery appears to develop with age.     

健脾补肾药对脾虚大鼠细胞因子水平的影响

目的 :观察健脾补肾方药对实验性脾虚证大鼠细胞因子的影响 ,探讨脾虚证与细胞因子的关系及脏腑相关的意义。方法 :选用SD雄性大鼠 ,随机分为 :正常对照组 ,脾虚模型组 ,健脾补肾方高、低剂量组 ,通过大黄复制脾虚证动物模型 ,并用健脾补肾方药进行防治。采用放射免疫分析观察各组动物血清肿瘤坏死因子(TNF)、白细胞介素 - 6 (IL - 6 )、白细胞介素 - 2 (IL - 2 )水平的变化。结果 :脾虚模型组大鼠血清TNF、IL - 6、IL - 2含量均比正常对照组显著降低 (p <0 0 1) ,而健脾补肾方药能明显升高TNF、IL - 6、IL - 2含量 ,使体重增加 ,脾脏和胸腺组织的重量增加。结论 :脾虚证的发生与细胞因子网络调节系统的失衡有关 ,而健脾补肾中药对实验性脾虚证有较好的防治作用 ,脾肾相关理论对实践有指导意义。     

Feeding NOD mice with pig splenocytes induces transferable mechanisms that modulate cellular and humoral xenogeneic reactions against pig spleen or islet cells

We have reported previously that oral administration of pig cells to NOD mice modified xenogeneic cellular response against pig islet cells (PICs), and hypothesized that it may have induced active suppression. This preliminary report evaluated only the effect of feeding pig cells by 'primary' proliferation, i.e. when splenocytes from fed mice are confronted with pig cells in vitro. The present study also considered 'secondary' proliferation and cytokine production after feeding and subsequent in vivo graft of pig cells. Additionally, serum IgM and IgG isotypes were quantified by ELISA using pig target cells. Induction of active mechanism by feeding was hypothetical, which led us here to transfer splenocytes from mice fed pig spleen cells (PSC) and evaluate 'primary' (after transfer) and 'secondary' (after transfer and subsequent graft of pig cells) proliferations and cytokine secretions in recipient mice. We also determined whether the effects of feeding pig cells persisted after depression of suppressor mechanisms by cyclophosphamide. Mice fed with PSC displayed increased 'primary' splenocyte proliferation to PSC or PIC (P < 0.0001), while 'secondary' responses were decreased (P < 0.03) in those fed PSC and subsequently grafted with PSC. The increased 'primary' and decreased 'secondary' proliferations were reduced (P < 0.04) by pretreatment with cyclophosphamide. The IL-10/ and IL-4/IFNgamma ratios produced in response to PSC increased (P < 0.04) in mice fed and grafted with PSC compared to those grafted only with PSC. IgM and IgG levels against pig cells were, respectively, increased (P < 0.04) and decreased (P < 0.04) in mice fed and grafted with PSC. IgG2a and IgG2b, but not IgG1, levels were lower (P < 0.01). These effects of feeding PSC on 'secondary' proliferation, cytokine and antibody productions, were not detected when mice were fed PSC only after graft with PSC. Transfer with splenocytes from mice fed PSC increased 'primary' proliferation of splenocytes from recipient mice in response to PSC (P < 0.02) or PIC (P < 0.05). After transfer with splenocytes from PSC-fed mice and graft with PSC, 'secondary' proliferation to pig cells were reduced (P < 0.04), and the IL-10/IFNgamma ratio produced in response to PSC was increased fourfold. Thus, oral administration of PSC induces active transferable mechanisms, characterized by a biphasic pattern with early increased 'primary' xenogeneic cellular reactions to both PSC and PIC, followed by decreased 'secondary' responsiveness and a concomitant shift of the Th1/Th2 balance towards greater Th2 influence. Decreased responsiveness may be due to active suppression, even though induction of anergy or deletion cannot be excluded.