Immunopathology of the salivary glands of the lips in Sj?gren's syndrome

The cellular composition of the salivary gland infiltrates in primary Sjogren's syndrome and the presence of lymphokines were evaluated using the Avidin-Biotin-Peroxidase technique in 10 biopsies from Sjogren's syndrome patients. The predominant cell was the T-helper/inducer lymphocyte. T-helper/T-suppressor ratio ranged from 1/1 to 10/1. Only few M were observed while NK cells were rare. More than 50% (50-100%) of the infiltrating cells were HLA-DR positive while epithelial cells were positive from 40-90% in all but 2 cases in which the positivity was 10%. The infiltrating cells were also positive for Leu-10 antigen (40-95%) in contrast to the epithelial cells. Both infiltrating and epithelial cells were reacting with anti IL-2 MoAb in high percentages (50-100%), while none of the infiltrating cells expressed IL-2 receptor. Finally, 40-100% of the infiltrating cells were IFN-gamma positive. The above data indicate that a salivary gland lesion in Sjogren's syndrome is the result of an immune process in which T-lymphocytes predominate producing lymphokines while the epithelial cells by expressing class II MHC molecules, play an important role in the general picture.     

Common T cell receptor clonotype in lacrimal glands and labial salivary glands from patients with Sjögren's syndrome.

Sjogren's syndrome (SS) is an autoimmune disease characterized by lymphocytic infiltration into lacrimal and salivary glands leading to symptomatic dry eyes and mouth. Immunohistological studies have clarified that the majority of infiltrating lymphocytes around the lacrimal glands and labial salivary glands are CD4 positive alphabeta T cells. To analyze the pathogenesis of T cells infiltrating into lacrimal and labial salivary glands, we examined T cell clonotype of these cells in both glands from four SS patients using PCR-single-strand conformation polymorphism (SSCP) and a sequencing method. SSCP analysis showed that some infiltrating T cells in both glands expand clonally, suggesting that the cells proliferate by antigen-driven stimulation. Intriguingly, six to sixteen identical T cell receptor (TCR) Vbeta genes were commonly found in lacrimal glands and labial salivary glands from individual patients. This indicates that some T cells infiltrating into both glands recognize the shared epitopes on autoantigens. Moreover, highly conserved amino acid sequence motifs were found in the TCR CDR3 region bearing the same TCR Vbeta family gene from four SS patients, supporting the notion that the shared epitopes on antigens are limited. In conclusion, these findings suggest that some autoreactive T cells infiltrating into the lips and eyes recognized restricted epitopes of a common autoantigen in patients with SS.     

Tissue infiltration in a CD8 lymphocytosis syndrome associated with human immunodeficiency virus-1 infection has the phenotypic appearance of an antigenically driven response.

HIV-1 infection may initiate to an HLA-associated response designated diffuse infiltrative lymphocytosis syndrome, characterized by increased numbers of circulating CD8 T cells that infiltrate salivary glands, lungs, gastrointestinal tract, and kidneys. Since this response could either be an antigenically driven process induced by HIV-1 or a lymphoproliferation of cells with neoplastic or unusual features, we sought to define the phenotype of the cellular populations, the nature of tissue derangement, and the tissue localization of virus in diffuse infiltrative lymphocytosis syndrome. Circulating CD8 T cells were greatly increased while CD4 T cell numbers remained in the range found in asymptomatic seropositive persons. The majority of CD8 and CD4 T cells in both blood and tissues had the memory phenotype of CD29+ (beta 1 integrin) and CD11a+/CD18 (beta 2 integrin) expression, but lacked markers of recent activation. A proportion of the circulating CD8 T cells also expressed CD57 (Leu 7) but not other markers of natural killer cells. HIV-encoded proteins were identified in tissue macrophages located in periacinar areas of the salivary glands. CD54 (intercellular adhesion molecule-1), a ligand for the CD11a integrin, was strongly expressed on postcapillary venule endothelium within lymphoid foci, and HLA-DR molecules were found on limited regions of ductular epithelium adjacent to lymphoid aggregates. These findings suggest that (a) the visceral lymphocytic infiltration in diffuse infiltrative lymphocytosis syndrome is an antigen-driven, and MHC-determined, host immune response to an element associated with HIV-1 infection, and (b) that the specific adhesive molecule interactions mediating the cellular influx, as well as the subsequent tissue damage, reflect altered patterns of gene expression in tissues undergoing an immune response.     

Identification of surface proteins mediating adherence of CD11/CD18-deficient lymphoblastoid cells to cultured human endothelium.

Patients with the severe form of leukocyte adhesion deficiency syndrome do not express the CD11/CD18 adhesion complex on any of their leukocytes. Nevertheless, their lymphocytes, unlike their phagocytes, emigrate to extravascular sites of inflammation, demonstrating that surface proteins other than CD11/CD18 can mediate lymphocyte adherence to endothelium. Using a B-lymphoblastoid cell line (B-LCL) established from a CD11/CD18-deficient patient and cultured human umbilical vein endothelial cells (HEC), we investigated the CD11/CD18-independent mechanism(s) of lymphocyte adherence to endothelium. Monoclonal antibodies directed to the alpha 4 polypeptide (CD49d) and the beta 1 polypeptide (CD29) of the lymphocyte VLA-4 integrin receptor (CD49d/CD29), and to vascular cell adhesion molecule-1 (VCAM-1) on the endothelial cell significantly inhibited the adherence of the CD11/CD18-deficient B-LCL to untreated HEC and to HEC treated with recombinant human tumor necrosis factor-alpha. We suggest that the interaction of the lymphocyte receptor VLA-4 with the endothelial ligand VCAM-1 induced by cytokines at sites of inflammation or immune reaction represents a CD11/CD18-independent pathway of lymphocyte emigration.     

Requirements for leukocyte adhesion molecules in nephrotoxic nephritis.

Requirements for leukocyte adhesion molecules as well as cytokines have been determined in the rat model of acute nephrotoxic nephritis. Proteinuria (at 24 h) and neutrophil accumulation in renal glomeruli (at 6 h) have been used as the endpoints. For full accumulation in glomeruli of neutrophils as well as full development of proteinuria, requirements have been demonstrated for TNF alpha, (but not IL-1), CD11b (but not CD11a), very late arising-4 (CD49d/CD29), and intercellular adhesion molecule-1 but not endothelial leukocyte adhesion molecule-1 (E-selectin). By immunohistochemical approaches, infusion of antibody to glomerular basement membrane induced glomerular upregulation of intercellular adhesion molecule-1, endothelial leukocyte adhesion molecule-1, and vascular adhesion molecule-1. Treatment of rats with anti-TNF alpha or soluble recombinant human TNF receptor-1 blocked this expression. Renal arterial infusion of TNF alpha induced glomerular expression of all three endothelial adhesion molecules, but infusion of IL-1 beta did not. These data suggest that, in neutrophil and complement-dependent anti-glomerular basement membrane-induced acute nephritis in rats, there are selective requirements for cytokines, beta 1 and beta 2 integrins, and endothelial adhesion molecules. These requirements contrast with those found in other vascular beds in which complement and neutrophil-induced vascular injury has been induced by deposition of immune complexes.     

Renal expression of intercellular adhesion molecule-1 in different forms of glomerulonephritis.

1. Expression of intercellular adhesion molecule-1 was investigated in five normal kidneys and 47 renal biopsies with the use of monoclonal antibody 7F7 and immunoperoxidase staining. 2. In the normal kidney, intercellular adhesion molecule-1 was expressed on endothelial cells of glomerular and peritubular capillaries, on Bowman's capsule, on some interstitial cells and weakly in the mesangium. 3. Increased glomerular staining was detected in early cases of rapidly progressing glomerulonephritis (5/8) and in some cases of non-IgA mesangioproliferative glomerulonephritis (5/9), IgA nephropathy (3/5), Henoch-Schoenlein purpura (2/2), lupus nephritis (5/6) and focal segmental glomerulosclerosis (1/3). A decrease in intercellular adhesion molecule-1 expression was noted in advanced rapidly progressive glomerulonephritis (3/8), two cases of membraneous nephropathy, one severe mesangioproliferative glomerulonephritis biopsy, the two membranoproliferative glomerulonephritis biopsies and in sclerotic loops in focal segmental glomerulosclerosis. 4. Expression de novo on tubular epithelial cells occurred in rapidly progressive glomerulonephritis, in membranoproliferative glomerulonephritis, and to a lesser extent in some cases of membraneous nephropathy, minimal change disease, IgA nephropathy, focal segmental glomerulosclerosis, a severe case of mesangioproliferative glomerulonephritis and in the mixed essential cryoglobulinaemia case. In 63% of positive tubuli, intraluminal cells which expressed CD18, the common beta-chain of leucocyte-function-associated antigen-1, Mac-1 and p150,95, were present. 5. Intercellular adhesion molecule-1 was also found on the majority (59%) of infiltrating mononuclear cells in all forms of glomerulonephritis.     

Endothelial cell activation in patients with systemic vasculitis

Vascular endothelial cells respond in vitro to a number of stimuli,and in particular to cytokines, by undergoing functional andmorphological alterations which endow them with the capacityto promote inflammatory reactions. We studied this process ofendothelial cell activation in 20 skin biopsies from 18 patientswith systemic vasculitis. At sites of cutaneous inflammation,blood vessels were lined with swollen endothelial cells whichexpressed increased levels of intercellular adhesion molecule-1(ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), andwere associated with a mononuclear cell inflammatory infiltrate.Neutrophil infiltration was only found in the presence of endothelialleucocyte adhesion molecule-1 (ELAM-1), which was expressedin 15/20 biopsies. ELAM-1 and VCAM-1 were associated with thepresence of inflammatory cytokines which induce expression ofthese molecules in cultured endothelial cells. Endothelial activationin vivo appears to parallel that observed in vitro, and is likelyto be important in determining the nature of an inflammatoryresponse.     

Involvement of oxidative stress and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) in inflammatory bowel disease

The pathophysiology of inflammatory bowel disease involves excessive immune effects of inflammatory cells against gut microbes. In genetically predisposed individuals, these effects are considered to contribute to the initiation and perpetuation of mucosal injury. Oxidative stress is a fundamental tissue-destructive mechanisms that can occur due to the reactive oxygen species and reactive nitrogen metabolites which are released in abundance from numerous inflammatory cells that have extravasated from lymphatics and blood vessels to the lamina propria. This extravasation is mediated by interactions between adhesion molecules including mucosal addressin cell adhesion molecule-1 and vascular cell adhesion molecule-1 on the surface of lymphocytes or neutrophils and their ligands on endothelial cells. Thus, reactive oxygen species and adhesion molecules play an important role in the development of inflammatory bowel disease. The present review focuses on the involvement of oxidative stress and adhesion molecules, in particular mucosal addressin cell adhesion molecule-1, in inflammatory bowel disease.     

Systemic endothelial activation is greater in septic than in traumatic-hemorrhagic shock but does not correlate with endothelial activation in skin biopsies

OBJECTIVE: Sepsis and severe trauma result in endothelial activation and damage. The activated endothelium expresses adhesion receptors that control leukocyte trafficking. After activation, some adhesion molecules are also released into plasma as soluble forms. The present study was designed to compare the expression of soluble cell adhesion molecules (sCAMs) in three groups of patients: those with septic shock, severe sepsis, and traumatic-hemorrhagic shock. In addition, the endothelial expression of these adhesive molecules was examined in skin biopsies. DESIGN: Prospective observational study SETTING: Intensive care unit at a university hospital PATIENTS: The study included 15 patients with septic shock (by Bone's definition), 11 patients with severe sepsis (by Bone's definition), and 13 patients with traumatic-hemorrhagic shock. Fifteen healthy blood donors served as controls. MEASUREMENTS AND MAIN RESULTS: Measurements of sCAMs were performed on days 1, 2, and 3 of the disease. On day 1, when compared with controls, sE-selectin, sP-selectin, soluble vascular cell adhesion molecule (sVCAM)-1, and soluble intercellular adhesion molecule (sICAM)-1 were markedly elevated in septic shock patients, whereas these sCAMs, except for sP-selectin, were within normal ranges in traumatic-hemorrhagic shock patients. In patients with severe sepsis, an earlier stage than septic shock in the sepsis continuum, intermediate values of sCAMs were found. In skin biopsies of septic shock patients, the endothelial cells expressed a bright staining of constitutive endothelial molecules (CD146, CD144, CD131). Inducible molecules (ICAM-1, VCAM-1, and E-selectin) were positively expressed with bright staining. The biopsies from traumatic-hemorrhagic shock patients showed a similar positive expression of endothelial molecules. CONCLUSION: The patterns of sCAMs indicate that the systemic activation of the endothelium is different in the three clinical entities, maximum in septic shock, intermediate in severe sepsis, and not different from controls in traumatic-hemorrhagic shock. Comparable endothelial activation as evidenced by skin biopsies suggests that caution is required in the interpretation of CAMs in plasma, which does not necessarily reflect the in situ activation state of endothelium.     

Modulation of monocyte-endothelial cell interactions by platelet microparticles.

Platelets, activated by various agonists, produce microparticles (MP) from the plasma membrane, which are released into the extracellular space. Although the mechanism of MP formation has been clarified, their biological importance remains ill defined. We have recently shown that platelet-derived MP influence platelet and endothelial cell function. In this study, we have further examined the mechanism of cellular activation by platelet MP. To address the possibility that they may influence monocyte-endothelial interactions, we used an in vitro assay to examine their effects on the adhesion of monocytes to human umbilical vein endothelial cells (HUVEC). Platelet MP increased the adhesion of monocytes to HUVEC in a time- and dose-dependent manner. Maximal adhesion of monocytes to resting HUVEC was observed after 24 h of stimulation with MP. Similar kinetics were observed with U-937 (human promonocytic leukemia) cells, used as a model for the blood-borne monocyte. Maximal adhesion of resting monocytes to MP-stimulated HUVEC was observed after 5 h of stimulation with MP. The EC50s for MP-induced increases in HUVEC, monocyte, and U-937 cell adhesion is 8.74, 43.41, and 10.83 microg/ml of MP protein, respectively. The induction of monocyte-endothelial adhesion was mimicked by arachidonic acid isolated from MP. The observed increased cellular adhesiveness correlated with MP-induced upregulation of cell adhesion molecules. MP-stimulated HUVEC increased intracellular cell adhesion molecule-1 (ICAM-1) but not vascular cell adhesion molecule-1 (VCAM-1), P-, or E-selectin expression. Monocyte and U-937 lymphocyte function-associated antigen-1 (CD11a/CD18) and macrophage antigen-1 (CD11b/ CD18, alpham/beta2) were both upregulated upon MP stimulation, but an increase in p150,95 (CD11c/CD18), very late antigen-1, or ICAM-1 expression was not observed. The functional importance of these changes was demonstrated with blocking antibodies. MP also induced the chemotaxis of U-937 cells in a dose-dependent manner with an EC50 of 4.40 microg/ml of MP protein. Similarly, arachidonic acid isolated from MP mimicked the chemotactic response. A role for PKC was implicated in both adhesion and chemotaxis. GF 109203X, a specific inhibitor of PKC, significantly reduced monocyte-endothelial adhesion, as well as U-937 chemotaxis. The demonstration that platelet MP may modulate important aspects of endothelial and monocyte function provides a novel mechanism by which platelets may interact with such cells in human atherosclerosis and inflammation.     

Increased binding of synovial T lymphocytes from rheumatoid arthritis to endothelial-leukocyte adhesion molecule-1 (ELAM-1) and vascular cell adhesion molecule-1 (VCAM-1).

The infiltration of the synovial membrane (SM) by mononuclear cells, mostly T cells, is a typical histopathological feature associated with rheumatoid arthritis (RA). The entry of T lymphocytes into the SM is believed to be mediated by a number of molecules in the endothelium that are induced in response to a series of inflammatory mediators. In this study, we have investigated the adhesion of synovial T cells from RA patients to two endothelial ligands: endothelial-leukocyte adhesion molecule-1 (ELAM-1), the only selectin known to function as a vascular addressin for T cells, and vascular cell adhesion molecule-1 (VCAM-1), the cellular ligand of VLA-4. Our results clearly demonstrate that synovial T cells isolated from both SM and synovial fluid (SF), bearing an activated and memory phenotype, displayed an enhanced capacity to interact with these two endothelial molecules as compared with T cells from peripheral blood (PB) either of the same RA patients or healthy donors. A further enhancement of VLA-4-mediated T cell binding to VCAM-1 and fibronectin could be observed when already in vivo-activated synovial T cells were stimulated in vitro with phorbol esters, suggesting the existence of several cellular affinity levels for both very late activation-4 (VLA-4) ligands. Moreover, both PB and synovial T cells from RA patients exhibited strong proliferative responses when they were cultured with either fibronectin or VCAM-1 in combination with submitogenic doses of anti-CD3 mAb. This increased endothelial binding ability of synovial T lymphocytes together with their proliferation in response to the interaction with VCAM-1 and fibronectin may represent important mechanisms in the regulation of T cell penetration and persistence in the chronically inflamed SM of RA.     

急性缺血性脑卒中患者白细胞粘附分子的表达及细胞内[Ca2+]变化的实验研究

目的探讨急性缺血性脑卒中患者外周血白细胞计数和粘附分子表达的变化,以及与中性粒细胞激活密切相关的细胞内游离钙离子浓度[Ca2+]变化,以期为脑卒中的发病机理和治疗提供有价值的理论依据.方法采用流式细胞术(FCM)检测白细胞粘附分子的表达及细胞内[Ca2+]的变化.结果脑卒中急性发作时,患者主要是中性粒细胞数增高明显,外周血白细胞CD11b、CD18的表达在发病24h内升高,同时,脑卒中患者中性粒细胞表面CD62L的表达在急性期明显降低,急性脑卒中患者中性粒细胞内[Ca2+]增加,中性粒细胞表面粘附分子CD11b、CD18的表达与细胞内[Ca2+]具有正相关性,CD62L的表达与[Ca2+]虽无明显的线性相关性,但随着[Ca2+]的增加,CD62L的表达具有下降的趋势.结论急性脑卒中发生时,白细胞被激活,粘附分子CD11b、CD18表达上调,介导白细胞与内皮细胞粘附增强,可能会加重缺血后迟发性神经元死亡的病理生理过程.同时,随着中性粒细胞的激活,细胞表面粘附分子CD62L的表达显著下调,细胞内[Ca2+]增加,在白细胞与内皮细胞的粘附过程中起重要作用.     

Biopsy of the minor salivary glands in the differential diagnosis of Sj?gren's syndrome and chronic sialadenitis

The authors studied minor salivary gland morphology of 59 patients with different forms of chronic sialadenitis and Sjogren's syndrome (SS). The presence of pathomorphological changes in the salivary gland was established in chronic sialadenitis as well as in SS. However, these changes had distinctive features: total involvement in SS and mosaic patterns in chronic sialadenitis. The authors made a conclusion of the systemic involvement of the salivary glands in chronic sialadenitis.     

B lymphocyte binding to E- and P-selectins is mediated through the de novo expression of carbohydrates on in vitro and in vivo activated human B cells.

Cell adhesion to endothelium regulates the trafficking and recruitment of leukocytes towards lymphoid organs and sites of inflammation. This phenomenon is mediated by the expression of a number of adhesion molecules on both the endothelium and circulating cells. Activation of endothelial cells (EC) with different stimuli induces the expression of several adhesion molecules (E- and P-selectins, ICAM-1, VCAM-1), involved in their interaction with circulating cells. In this report, we have studied the binding of nonactivated and activated B cells to purified E- and P-selectins. Activated but not resting B cells were able to interact with both selectins. This binding capacity of activated B cells paralleled the induction of different carbohydrate epitopes (Lewisx, sialyl-Lewisx, CD57 and CDw65) as well as other molecules bearing these or related epitopes in myeloid cells (L-selectin, alpha L beta 2 and alpha X beta 2 integrins, and CD35) involved in the interaction of different cell types with selectins. B cells infiltrating inflamed tissues like in Hashimoto's thyroiditis, also expressed these selectin-binding carbohydrates in parallel with the expression of E-selectin by surrounding follicular dendritic cells. Moreover, the crosslinking of these selectin-binding epitopes resulted in an increased binding of B cells to different integrin ligands. Thus, in addition to the involvement of integrins, E- and P-selectins could play an important role in the interaction of B lymphocytes with the endothelium during B cell extravasation into lymphoid tissues and inflammatory foci as well as in their organization into lymphoid organs.     

Homing of mucosal leukocytes to joints. Distinct endothelial ligands in synovium mediate leukocyte-subtype specific adhesion.

Inflammation and infection of the gut can be followed by reactive arthritis at a distant joint. Leukocyte recruitment into synovium is essential for this process, but nothing is known about the endothelial adhesion molecules in synovial membrane which direct the homing of activated, gut-derived leukocytes to joints. Here we analyzed the expression of the known endothelial adhesion molecules in inflamed synovium and their function in binding of mucosal leukocytes. Intercellular adhesion molecule-1 (ICAM-1/CD54) and vascular adhesion protein-1 (VAP-1) were most prominently expressed in synovial vessels. All other adhesion molecules were found at lower levels in inflamed synovia, except mucosal addressin which was absent. Binding of macrophages isolated from lamina propria of the gut to synovial endothelium was almost entirely P-selectin-dependent. In contrast, small intestinal lymphocytes and immunoblasts both relied mainly on VAP-1 in recognition of synovial vessels. Thus, endothelial P-selectin and VAP-1 mediate binding of mucosal effector cells to synovium in a leukocyte subtype-selective manner. Antiadhesive therapy against these inducible molecules should ablate the pathogenetic cascade leading to inappropriate homing of leukocytes to joints in arthritis.     

Human leucocyte-endothelial interactions in peripheral arterial occlusive disease

Abstract. This ex vivo study determined the expression of leucocyte adhesion receptors for endothelial adhesion molecules in 10 patients with peripheral arterial occlusive disease (PAOD) and in 10 healthy controls before and after treadmill exercise. Granulocytes from venous blood samples were separated on a Ficoll-Hypaque gradient and the phenotypical expression of CD11a/CD18 (LFA-1), CD11b/CD18 (Mac-1) and CD11c/CD18 (p150,95) was observed by double indirect immunofluorescence using specific monoclonal antibodies. The total and differential white blood cell counts were monitored before and after exercise. In the PAOD patients a significant reduction in the number of granulocytes expressing CD11b/CD18 (Mac-1) and CD11c/CD18 (p150,95) associated with a significant neutropenia was observed after exercise, suggesting that leucocyte-endothelial interactions occur during ischaemia.     

缺氧缺血性脑病新生兔细胞粘附分子表达的变化

目的:观察缺氧缺血性脑病(HIE)对新生兔细胞粘附分子表达的影响。方法:采用结扎左颈总动脉后置于低氧状态容器中2h的方法制作HIE模型兔32只,分4组,每组8只,分别于模型制作成功后2h、12h、24h、48h测定中性粒细胞表面细胞粘附分子CD11b、CD18,脑组织细胞粘附分子ICAM-1及血管内皮细胞粘附分子VCAM-1,并与对照组进行比较。结果:HIE组CD11b、CD18,ICAM-1、VCAM-1的表达明显高于对照组,缺氧缺血2h即见表达增强,在24h达到高峰,48h时稍下降,但仍在较高水平,与对照组比较差异有显著性。结论:缺氧缺血性脑病新生兔中性粒细胞CD11b、CD18、脑细胞细胞粘附分子ICAM-1、血管内皮细胞粘附分子VCAM-1表达增强,细胞粘附分子的变化参与HIE的病理生理过程。     

Endothelial-leukocyte adhesion molecule 1 stimulates the adhesive activity of leukocyte integrin CR3 (CD11b/CD18, Mac-1, alpha m beta 2) on human neutrophils.

Two classes of adhesion molecules have well-defined roles in the attachment of unstimulated polymorphonuclear leukocytes (PMN) to cytokine-treated endothelial cells. Endothelial-leukocyte adhesion molecule 1 (ELAM-1) on endothelial cells interacts with specific carbohydrate residues on the PMN, and the leukocyte integrins (CD18 antigens) on PMN interact with intracellular adhesion molecule 1 and other structures on endothelium. Here we show that these two classes of molecules can act sequentially in an "adhesion cascade". Interaction of PMN with ELAM-1-bearing endothelial cells causes PMN to express enhanced adhesive activity of the integrin CR3 (CD11b/CD18). Expression of ELAM-1 on the cytokine-treated endothelium appears both necessary and sufficient for the stimulation of CR3 activity since blockade of ELAM-1 with mAbs prevents the activation of CR3 by cytokine-treated endothelium, and immobilized recombinant ELAM-1 activates CR3. The ability to activate CR3 is shared by chemattractants, suggesting that ELAM-1 may serve as a "tethered chemattractant." This hypothesis is strengthened by the observation that recombinant soluble ELAM-1 directs movement of PMN in chemotaxis chambers. These results suggest a mechanism by which multiple adhesive molecules may function together in diapedesis. ELAM-1 serves both as an adhesin and as a trigger that recruits the participation of additional adhesion molecules. Our results also suggest that ligands for adhesion molecules may also be "receptors" capable of generating intracellular signals.     

BST-2在pSS患者唇腺、外周血淋巴细胞中的表达及增殖作用

目的探讨原发性舍格伦综合征(pSS)患者唇腺及外周血B淋巴细胞中骨髓基质细胞抗原2(BST-2)的表达情况及其在pSS中的作用。方法将2017年9月至2018年3月在内蒙古自治区人民医院接受治疗的40例pSS患者作为pSS组;将同期体检的30例健康者作为对照组。采用实时荧光定量PCR检测纳入研究者的唇腺组织及外周血B淋巴细胞中BST-2的表达水平。免疫组织化学法检测唇腺组织内BST-2的表达情况,并分析BST-2对淋巴细胞增殖的影响。结果pSS组的外周血B淋巴细胞和唇腺组织中BST-2的表达水平明显高于对照组(P<0.05);pSS患者唇腺组织中浸润的局灶性淋巴细胞和少数周围导管上皮内BST-2表达量较高,而在对照组中仅在导管上皮细胞内存在散在性少量表达。连续切片的pSS患者唇腺组织染色显示,pSS患者的唇腺组织内CD19染色阳性细胞和BST-2阳性细胞基本一致。结论pSS患者唇腺组织和外周血B淋巴细胞BST-2水平明显增高;BST-2通过对腺体内B淋巴细胞的浸润及增殖,参与pSS的发病及进展。