Adhesion Molecules Lymphocyte Function-associated Antigen-1 Research Articles

LFA-1 regulated by IL-2/STAT5 pathway boosts antitumor function of intratumoral CD8+ T cells for improving anti-PD-1 antibody therapy

ABSTRACT Anti-PD-1 antibody therapy has achieved success in tumor treatment; however, the duration of its clinical benefits are typically short. The functional state of intratumoral CD8+ T cells substantially affects the efficacy of anti-PD-1 antibody therapy. Understanding how intratumoral CD8+ T cells change will contribute to the improvement in anti-PD-1 antibody therapy. In this study, we found that tumor growth was not arrested after the late administration of anti-PD-1 antibody and that the antitumor function of CD8+ T cells decreased with tumor progression. The results of the RNA sequencing of CD8+ T cells infiltrating the tumor site on days 7 and 14 showed that the cell adhesion molecule Lymphocyte Function-associated Antigen-1 (LFA-1) participates in regulating the antitumor function of CD8+ T cells and that decreased LFA-1 expression in intratumoral CD8+ T cells is associated with tumor progression. By analyzing the Gene Expression Omnibus (GEO) database and our results, we found that the antitumor function of intratumoral CD8+ T cells with high LFA-1 expression was stronger. The formation of immune synapses is impaired in Itgal-si CD8+ T cells, resulting in decreased anti-tumor function. LFA-1 expression in intratumoral CD8+ T cells is regulated by the IL-2/STAT5 pathway. The combination of IL-2 and anti-PD-1 antibody effectively enhanced LFA-1 expression and the antitumor function of intratumoral CD8+ T cells. The adoptive transfer of OT-1 T cells overexpressing LFA-1, STAT5A, or STAT5B resulted in higher antitumor function, deferred tumor growth, and prolonged survival. These findings indicate that LFA-1-mediated immune synapse acts as a regulator of the antitumor function of intratumoral CD8+ T cells, which can be applied to improve anti-PD-1 antibody therapy.

Dual-functional capability of CD3+CD56+ CIK cells, a T-cell subset that acquires NK function and retains TCR-mediated specific cytotoxicity

AbstractCD3+CD56+ cytokine-induced killer (CIK) cells display a potent cytolytic activity. The adhesion molecule lymphocyte function-associated antigen-1 plays a crucial role in binding as well as in cytolytic activity of CIK cells against tumor target cells expressing the corresponding ligands. CIK cells express activating natural killer (NK) receptors, including NKG2D, DNAX accessory molecule-1 (DNAM-1), and low levels of NKp30. Cell signaling not only through TCR/CD3 but also through NKG2D, DNAM-1, and NKp30 leads to CIK cell activation resulting in granule exocytosis, cytokine secretion, and cytotoxicity. Antibody blocking experiments showed that DNAM-1, NKG2D, and NKp30 are involved in the TCR-independent tumor cell recognition and killing. Anti–CMV-specific CIK cells could be expanded in standard CIK cultures and mediate both specific, MHC-restricted recognition and TCR-independent NK-like cytolytic activity against leukemic cell lines or fresh leukemic blasts. Antibody blocking of lymphocyte function-associated antigen-1 and DNAM-1 led to significant reduction of both CTL and NK-cell functions, whereas blocking of NKG2D and NKp30 only inhibited NK-like cytotoxicity. Their dual-effector function suggests that CIK cells, when used in a clinical setting, may control both neoplastic relapses and viral infections, 2 frequently associated complications in patients who received a transplant.

Anti–LFA-1 Monotherapy Prevents Neointimal Formation in a Murine Model of Transplant Intimal Hyperplasia

Cardiac allograft vasculopathy (CAV) is the pre-eminent cause of late cardiac allograft failure. It is characterized by a concentric intimal hyperplasia, which we designate transplant intimal hyperplasia (TIH). To date, blockade of the adhesion molecule lymphocyte function-associated antigen-1 (LFA-1) has been shown to be effective in preventing TIH in experimental models of transplantation, but only when combined with other immunosuppressants. In this study we explored the impact of monotherapy against LFA-1 in a carotid artery allograft model of TIH. B10A(2R) (H-2(h2)) mice were used as donors and C57BL/6 (H-2(b)) mice used as recipients. The recipients were treated with a monoclonal antibody against LFA-1alpha (M17/4) or isotype-matched control immunoglobulin. Grafts were harvested after 35 days and analyzed by histomorphometry and immunohistochemistry. Blood samples were taken and analyzed by differential cell count and alloantibody levels. We found that treatment with M17/4 resulted in a significant reduction in TIH compared with controls. Immunostaining revealed that LFA-1alpha blockade inhibited CD45+ leukocyte infiltration, prevented intimal smooth muscle cell (SMC) proliferation, and preserved the medial SMC population. Finally, we demonstrated a reduction in the serum alloantibody titer in the group treated with anti-LFA-1alpha when compared with controls. We have demonstrated for the first time that LFA-1alpha blockade on its own can prevent development of TIH in an experimental model. The concept of modulating LFA-1alpha-mediated leukocyte migration and T-cell activation may therefore be of relevance to clinical cardiac transplantation and, as such, represents a potential target for therapeutic intervention against clinical CAV.

Blocking of up-regulated ICAM-1 does not prevent macrophage infiltration during Wallerian degeneration of peripheral nerve

Circulating blood monocytes infiltrate into distal degenerating nerve and differentiate into activated macrophages that remove degenerating axonal and myelin debris and promote axonal regeneration. The cellular and molecular mechanisms responsible for this monocyte–macrophage recruitment remain largely unknown. Cell adhesion molecules which mediate monocyte and endothelial cell interactions, such as the endothelial cell adhesion molecule intercellular adhesion molecule-1 (ICAM-1) interaction with the monocyte adhesion molecules Mac-1 (complement receptor type 3) and LFA-1 (lymphocyte function-associated antigen-1), have been shown to play a critical role in mediating the transendothelial migration of circulating monocytes into nonneural tissues following various types of injury. This study investigated whether these cell adhesion molecules also play a critical role in mediating monocyte–macrophage infiltration during Wallerian degeneration of peripheral nerve. Following sciatic nerve transection, Mac-1- and LFA-1-positive macrophages in distal degenerating nerve increased in number at 2 days and peaked at 14 days before declining. The number of ICAM-1-immunostained blood vessels increased maximally at 1 day before declining to baseline levels by 14 days. Three days following nerve transection, the intensity of ICAM-1 immunostaining on intraneural blood vessels was maximal and then decreased to baseline levels by 14 days. To test the role of ICAM-1 in mediating monocyte–macrophage recruitment, we used two complementary experimental strategies following a sciatic nerve transection: (1) intravenous administration of a rat ICAM-1-blocking monoclonal antibody and (2) ICAM-1 knockout mice. In both cases, the number of infiltrating monocytes–macrophages was above controls, which is opposite to what has been shown to occur in other tissues following injury.

Cytotoxic T lymphocyte-associated antigen-4 inhibits integrin-mediated stimulation.

The negative role exerted by cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) in the regulation of T-cell activity, as induced by T-cell receptor (TCR)/CD3 and CD28 costimulation, has been widely described. In the present work we investigated the role of CTLA-4 in the control of cell activation, as induced by costimulation of the adhesion molecule lymphocyte function-associated antigen-1 (LFA-1) in murine CD4+ T cells. Results show that CTLA-4 engagement inhibits interleukin-2 (IL-2) production, not only when induced by CD3/CD28 costimulation, but also when CD4+ T cells are costimulated by anti-CD3 and anti-LFA-1 monoclonal antibodies (mAbs). LFA-1 has been described to induce Ca2+ mobilization also in the absence of TCR engagement. Moreover, we found that CTLA-4 engagement negatively affects Ca2+ mobilization and NF-AT activation, as induced by LFA-1 engagement alone. PLCgamma1 phosphorylation was also dampened within minutes after CTLA-4 engagement. Altogether these data indicate that through the control of signals induced by different receptors, CTLA-4 could be a global attenuator of T-cell activation.

Amelioration of Graft versus Host Disease with Anti-ICAM-1 Therapy

We have previously demonstrated an increase in the adhesion molecule lymphocyte function-associated antigen-1 (LFA-1) in GVHD after small bowel transplantation (SBTx) and a therapeutic effect for the monoclonal antibody (MoAb) to LFA-1 in the same model. The present study evaluated the role of MoAb to LFA-1's ligand, intercellular adhesion molecule-1 (ICAM-1) in GVHD.Methods.GVHD was created in LBNF1rats by heterotopic vascularized SBTx from Lewis donors. Saline treated SBTx-GVHD and sham-operated control animals were compared to animal groups treated with MoAb to ICAM-1 or MoAb to ICAM-1 and LFA-1. GVHD was evaluated by measuring spleen index, white blood cell count, bowel permeability, weight loss, and animal survival.Results.Animals treated with the MoAb to ICAM-1 appeared clinically to have almost as severe GVHD as untreated animals; however, they had improved spleen indices, less neutropenia and weight loss, and survived longer than untreated animals (range 15–22 days in treated animals vs 12–16 days in untreated animals,P< 0.01). Treatment with MoAb to both ICAM-1 and LFA-1 appeared to have a synergistic beneficial effect on GVHD (range 19–29 days,P< 0.001 vs untreated animals).Conclusion.MoAb to ICAM-1 alone or in combination with MoAb to LFA-1 ameliorates GHVD after SBTx and prolongs survival.

Adhesion molecules in intestinal Schistosoma mansoni infection.

Adhesion molecules constitute essential elements in inflammation, mediating various cellular interactions. We investigated the expression of adhesion molecules mediating cell-cell [intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-1 (LFA-1)] and cell-matrix interactions [very late antigen-4 (VLA-4), VLA-6, and syndecan-1] in intestinal granulomas of mice infected with the parasite Schistosoma mansoni. Up-regulation of ICAM-1, LFA-1, and VLA-4 was seen in ileal and colonic granulomas, at both the acute (8 weeks postinfection) and the chronic stage (13-16 weeks postinfection). Up-regulation of VLA-6 was absent in all intestinal granulomas. Syndecan-1 immunoreactive (antigen-driven) B-lymphocytes were seen in the proximity of egg-antigen-laden macrophages in the inner part of ileal and colonic granulomas, although B-cells are considered to be absent in ileal granulomas. Estimation of intestinal granuloma volumes demonstrated the lack of down-modulation observed in ileal granulomas. From our results we infer that adhesion molecules constitute important elements in schistosomal intestinal granuloma formation. Organ-related differences between hepatic and intestinal granulomas exist (e.g., granuloma volume), but these differences are not morphologically reflected in a differential expression of the adhesion molecules ICAM-1, LFA-1, and VLA-4. Syndecan-1 immunoreactive B-lymphocytes also appear to be involved in ileal granuloma formation.

Increased Expression of Neutrophil and Monocyte Adhesion Molecules LFA-1 and Mac-1 and Their Ligand ICAM-1 and VLA-4 Throughout the Acute Phase of Myocardial Infarction: Possible Implications for Leukocyte Aggregation and Microvascular Plugging

Objectives. This study sought to evaluate expression of adhesion molecules on neutrophils and monocytes throughout the acute phase of myocardial infarction.Background. Neutrophil and monocyte counts increase within days from onset of acute myocardial infarction. Because leukocytes are recruited to the involved myocardial region, we postulated that these activated cells would display an increased expression of adhesion molecules necessary for effective endothelial transmigration.Methods. We measured the expression of neutrophil and monocyte lymphocyte function associated antigen-1 (LFA-1), Mac-1, very late after activation antigen-4 (VLA-4) and intercellular adhesion molecule-1 (ICAM-1) by flow cytometry throughout the acute phase of acute myocardial infarction in 25 patients and 10 age-matched control subjects.Results. Expression of Mac-1 on neutrophils increased significantly, whereas no expression of VLA-4 and ICAM-1 was detected. The expression of LFA-1, Mac-1, VLA-4 and ICAM-1 on the monocyte cell membrane in patients with an acute myocardial infarction was increased compared with that in control subjects by 22% (on day 7), 67%, 13% and 44% (all on day 4), respectively (all p < 0.001). Elevated density of monocyte-specific CD14 in the AMI versus the control group was also shown (30%, p < 0.001).Conclusions. Increased expression of neutrophil and monocyte adhesion molecules may contribute to their adhesion to endothelium in the ischemic territory. This adhesion could feasibly precipitate vasoconstriction or add a local thrombotic effect due to tissue factor expression secondary to Mac-1 engagement. In addition, the manifestation of increased density of LFA-1 and Mac-1 by activated leukocytes with monocytes also expressing ICAM-1 suggests that leukocytes may form microaggregates that could cause microvascular plugging. This mechanism may facilitate the occurrence of the “no-reflow” phenomenon or slow coronary filling after acute myocardial infarction.

Trypanosoma cruzi-infected macrophages are defective in major histocompatibility complex class II antigen presentation.

Trypanosoma cruzi, the intracellular protozoan parasite that causes Chagas' disease, interferes with the host immune response to establish a persistent infection. In this report, we demonstrate that macrophages infected with T. cruzi are unable to effectively present antigens to CD4 T cells. The interference is due to defective antigen-presenting cell (APC) function, as antigen-independent stimulation of the T cell in the presence of infected macrophages is not affected. The defect is distal to antigen processing and is not due to decreased major histocompatibility complex (MHC) class II expression, decreased viability, defective peptide loading in the infected macrophages, nor absence of CD28 co-stimulation. There was a role for gp39: CD40 co-stimulation during antigen presentation to the T cells we studied, but the expression of CD40 on T. cruzi-infected macrophages was not decreased. Antigen-specific adhesion between macrophages and T cells was reduced by infection. Equivalent levels of the adhesion molecules lymphocyte function-associated antigen-1, intercellular adhesion molecule-1, vascular cell adhesion molecule-1 or very late antigen-4 are found on infected and uninfected APC, suggesting that reduced expression of these adhesion molecules was not responsible for the defect in antigen-specific adhesion. The defective T cell:macrophage adhesion may be due to the reduced expression of other adhesion molecules or other changes in the cell induced by infection. Interfering with MHC class II antigen presentation in infected macrophages may help T. cruzi to blunt the immune response by the host.

Adhesion molecule LFA-1/ICAM-1 influences on LPS-induced megakaryocytic emperipolesis in the rat bone marrow.

To investigate the effect of adhesion molecules on the occurrence of megakaryocytic emperipolesis of neutrophils, we examined the expression of lymphocyte function-associated antigen 1 (LFA-1) and intercellular adhesion molecule 1 (ICAM-1) in the bone marrow of lipopolysaccharide (LPS)-treated rats (experiment I) and the occurrence of megakaryocytic emperipolesis in anti-LFA-1 antibody-treated rats (experiment II). In experiment I, rats were injected with LPS intravenously at a daily dose of 0.5 mg/kg for 3 days. ICAM-1 was intensely stained on megakaryocytes in LPS treated rats, as detected by flow cytometric analysis. ICAM-1 was immunostained in the megakaryocytes showing emperipolesis. LFA-1 was immunostained in the neutrophils engulfed by megakaryocytes. In experiment II, rats received anti-LFA-1 antibody intravenously at a single dose of 3 mg/kg. One hour after treatment, rats were given LPS intravenously as a single dose of 0.5 mg/kg. The incidence of megakaryocytic emperipolesis was markedly lower in the anti-LFA-1 antibody + LPS group than in the LPS alone group. These findings suggest that the occurrence of megakaryocytic emperipolesis is partly dependent on adhesion molecules via LFA-1/ICAM-1.

Interleukin-2 induces increased platelet-endothelium interactions: A potential mechanism of toxicity

Cancer immunotherapy with interleukin-2 (IL-2) is limited by side effects that may cause organ dysfunction. The role of platelets in the generation of IL-2-induced organ dysfunction has not been studied, although various studies have shown that IL-2 therapy activates both platelets and the vascular endothelium. We hypothesized that IL-2 therapy may enhance the thrombogenic response to inflammatory stimuli through increased platelet-endothelial interactions and that these effects could lead to the development of organ dysfunction. C57B1/6 mice were treated with IL-2 intraperitoneally for 2 hours (short term) or 2 to 5 days (long term) and prepared for in vivo microscopy of the ear microcirculation. Mice were injected intra-arterially with fluorescein isothiocyanate conjugated to bovine serum albumin (FITC-BSA). Blue light activation of the FITC-BSA in ear arterioles induced thrombus formation. The time to initial thrombus formation was measured as an index of thrombogenicity. Platelet function was analyzed by aggregometry and platelet expression of IL-2 receptors, and the adhesion molecule lymphocyte function-associated antigen-1 (LFA-1) was analyzed by flow cytometry. Organ dysfunction was evaluated by serum markers. The administration of both short-term and longterm IL-2 reduced the time to initial thrombus formation as compared with controls. In vitro platelet aggregometry revealed no acute alterations in platelet function; however, long-term IL-2 treatment resulted in decreased disaggregation rates. There were no platelet IL-2 receptors present, and the expression of the adhesion molecule LFA-1 was not altered by IL-2. Increased thrombogenicity occurred before the generation of organ dysfunction. These data suggest that increased platelet adherence induced by IL-2 is caused by effects on the endothelium that could result in microvascular thrombus formation and contribute to organ dysfunction.

Low Expression of Adhesion Molecules in a Case of Cutaneous T‐cell Lymphoma

A case of cutaneous T-cell lymphoma (CTCL) with low expression of the adhesion molecules lymphocyte function-associated antigen-1 (LFA-1), intercellular adhesion molecule-1 (ICAM-1), and very late antigen-4 (VLA-4) is described. The patient was a 90-year-old man with red round homogeneous tumors on his scalp, trunk, and extremities. He had no history of definite erythema or plaque stage. A biopsy sample taken from a tumor revealed massive infiltration of atypical lymphocytes in the reticular dermis and subcutis with a definite clear zone. The atypical lymphocytes were medium-sized with slightly convoluted nuclei. Immunohistochemically, the infiltrates showed the phenotype of so-called memory T cells. On the basis of these features, the case was diagnosed as CTCL. Expression of LFA-1, ICAM-1 and VLA-4 on the infiltrates was 9%, 13% and 11%, respectively, which is much lower than that in classic mycosis fungoides. This finding suggests that loss of these adhesion molecules may contribute to loss of epidermotropism in the advanced stage of CTCL.

Involvement of Granulocytes and the Adhesion Receptors Intercellular Adhesion Molecule-1 and Lymphocyte Function-Associated Antigen-1 in Tissue Inflammation Induced by Th2-Type Helper Cells

We reported recently that subcutaneously injected, anti-CD3 epsilon-pulsed polyclonal Th2 cells mediate interleukin-4-dependent local tissue inflammation. Because a prominent polymorphonuclear infiltrate was observed in the lesions at the time of maximal tissue swelling, we investigated the involvement of polymorphonuclear leukocytes and their adhesion molecules lymphocyte function-associated antigen-1 (LFA-1) and intercellular adhesion molecule-1 (ICAM-1) in Th2-cell-mediated inflammation. Pretreatment of recipient mice with a depleting monoclonal antibody to neutrophils or with blocking antibodies to LFA-1 or to ICAM-1 completely abrogated tissue swelling in Th2-cell-mediated inflammation. Granulocyte infiltration at 6 h was also inhibited by the antibodies to neutrophils and to ICAM-1, but not by that to LFA-1. Tissue swelling mediated by Th1 cells had different kinetics and was not prevented by administration of anti-neutrophil antibody: maximal edema formation occurred at 24-48 h, when the predominant cellular infiltrate was mononuclear. Because the Th1-cell-induced infiltrate at 6 h also consisted of granulocytes but was not associated with pronounced edema, the mere presence of infiltrating polymorphonuclear leukocytes seems not to be sufficient to induce edema. Because edema but not granulocyte infiltration was inhibited by anti-LFA-1 and because anti-LFA-1 antibodies are known to inhibit several functions of neutrophils, our results suggest that, in inflammation mediated by Th2 cells, granulocytes induce edema through their activation and/or degranulation.

Recruitment and recirculation of leukocytes after an ultramarathon run: preferential homing of cells expressing high levels of the adhesion molecule LFA-1.

The alpha L beta 2 (CD11a/CD18) integrin LFA-1 (lymphocyte function-associated antigen-1) mainly contributes to the firm arrest of leucocytes on the endothelium. Its cell surface density is thought to be important for the exercise-induced homing of leucocytes. 9 athletes (7 males, 2 females, age 36-68 years, body mass 64 +/- 10 kg, height: 175 +/- 10 cm) absolved a competitive 100 km run in 8:07 hours (range: 7:29-9:50 hours). Immunophenotyping of circulating leucocytes and data acquisition by three colour flow cytometry before and up to 3 hours after the race showed that post exercise lymphocyte subpopulations with a higher expression of CD11a like CD3+CD8+CD45RO+ T-cells, natural killer cells (CD3-CD16/CD56+) and cytotoxic, not MHC-restricted T-cells (CD3+CD16/CD56+) decreased significantly more than CD45RO+ and CD45RO- helper-T-cells (CD3+CD4+), CD3+CD8+CD45RO-T-cells and B-cells (CD19+), which have lower levels for CD11a. Cell concentrations of regular monocytes (Fc gamma receptor 3 negative, LFA-1 low positive) increased, whereas mature monocytes (Fc gamma receptor 3 low or high positive respectively, LFA-1 high positive) decreased. In conclusion the surface density of the adhesion molecule LFA-1 on leucocytes is likely to contribute significantly to the extent of leucocyte's homing after long endurance exercise.

Xenotransplantation: an examination of the adhesive interactions between human lymphocytes and porcine renal epithelial cells

Specific adhesion molecules stabilize the binding between lymphocytes and antigen bearing cells; this intercellular adhesion is vital to both the affector and effector phases of an immune response. It is not known whether adhesion molecules and their counter-receptors can form the cross-species interactions that will facilitate human T cell recognition of xenogeneic porcine target cells. In this report it is demonstrated that a higher proportion of mitogen-activated than of resting human lymphocytes adhere to cultured porcine renal epithelial cells. Furthermore, antibody blocking experiments demonstrated that at least part of this cell-cell binding is stabilized by the human adhesion molecules LFA-1 (lymphocyte function-associated antigen-1) and the α 4-containing integrins. It is possible that this capacity for cross-species adhesion will play a role during the cell-mediated rejection of clinical porcine xenografts.

Effect of nonsteroidal anti-inflammatory drugs on LFA-1 and ICAM-1 expression in gastric mucosa.

Leukocyte adhesion to the endothelium appears to play an important role in gastric injury. This study aimed to develop immunohistochemical staining techniques to investigate the distribution and sequence of expression of both leukocyte [lymphocyte function associated antigen 1 (LFA-1)] and endothelial [intracellular adhesion molecule 1 (ICAM-1)] adhesion molecules in the mucosa after treatment with nonsteroidal anti-inflammatory drugs (NSAIDs). In control rats there were 803 +/- 72 LFA-1-stained cells/mm2 in the deep mucosa, 134 +/- 32 cells/mm2 in the superficial mucosa, and 6.4 +/- 1.2 ICAM-1-stained blood vessels/mm2 in the total mucosa. The number of ICAM-1-stained blood vessels in the mucosa increased significantly after 30 min of treatment with intragastric aspirin (30 mM; 25.2 +/- 7.2/mm2, P < 0.01) and indomethacin (20 mg/kg; 20.7 +/- 4.4/mm2, P < 0.01) before any appreciable mucosal damage was evident. This increase was reversed by treatment with misoprostol (100 micrograms/kg) in both aspirin- (7.6 +/- 1.7/mm2, P < 0.01) and indomethacin-treated animals (10.7 +/- 2.6/mm2, P < 0.05). There was no significant increase in LFA-1-positive cells until 60 min of NSAID treatment. We conclude that the adhesion molecules LFA-1 and ICAM-1 are expressed in the normal gastric mucosa and that the number of ICAM-1-stained blood vessels increase rapidly after NSAID treatment. This increase in ICAM-1 expression may be associated with an inhibition of prostaglandin synthesis by NSAIDs. These results provide further support for the role of early vascular changes in NSAID gastropathy.

Cell surface expression and serum levels of intercellular adhesion molecule-1 in renal cell carcinoma.

Intercellular adhesion molecule-1 (ICAM-1) is the natural ligand of the T-lymphocyte adhesion molecule LFA-1 (lymphocyte-function-associated antigen-1). ICAM-1 is involved in target cell recognition by T-lymphocytes, LAK cells and natural killer cells. The molecule has also been detected on a variety of normal cells and on human tumors. Renal cell carcinoma (RCC) is one of the few tumors that respond to immunotherapy, but clinical results are generally disappointing. We therefore analyzed, by immunohistochemistry, the expression of ICAM-1 in pairs of normal kidneys, RCC, and RCC metastases. Moreover, serum ICAM-1 was determined in RCC patients and compared with surface expression of cell-bound ICAM-1. Strong glomerular expression of ICAM-1 was observed in all specimens of normal kidney examined. Proximal tubuli were weakly stained in the majority of specimens. Of the tumors, 80% stained positive for ICAM-1. Although ICAM-1 was detected on the majority of extrarenal tumor specimens examined, staining was generally weaker in the metastases. Patients without metastases at initial presentation more frequently expressed ICAM-1 in their primary tumors than did patients with metastases. Levels of serum ICAM-1 (sICAM-1) were significantly higher in RCC patients than in controls with non-malignant renal diseases. Patients with an unfavorable prognosis, e.g. with advanced tumor stage or metastasis at initial presentation, had higher levels of sICAM-1 than patients with low-grade and/or low-stage tumors.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of adhesion molecules in poststreptococcal glomerulonephrities

Because adhesion properties of leukocytes are important for the influx and localization of leukocytes in sites of inflammation, we studied, the expression of intercellular adhesion molecule 1 (ICAM-1), lymphocyte-function-associated antigen 1 (LFA-1), vascular cell adhesion molecule- 1 (VCAM-1) and CD 11b in 14 kidney biopsies of PSGN patients, arbitrarily divided into early biopsies (less than 15 days after onset of PSGN) and late biopsies (17-90 days). In PSGN, intraglomerular ICAM-1 expression was increased in early biopsies (score 3.1 +/- SEM 0.2; P < 0.005) and decreased with time; in late biopsies the score (2.0 +/- 0.2) was similar to that of normal kidney (1.3 +/- 0.3). In the interstitium ICAM-1 was increased (early PSGN = 836 +/- 56 positive cells/mm2, late = 552 +/- 60.0; versus normal = 364 +/- 12.4; P < 0.05). LFA-1 expressing cells in glomeruli were also increased in early biopsies (10.0 +/- 2.1 positive cells per glomerular cross-section (gcs), versus normal 2.9 +/- 1.4; P < 0.05). In the interstitium, LFA-1 positive cells were increased (early PSGN = 221 +/- 79.6 cells/mm2, late PSGN = 134.5 +/- 45.1, normal = 21 +/- 8.7; P < 0.05). VCAM-1 in glomeruli and interstitium was not increased in PSGN. Our studies demonstrate increased expression of adhesion molecules ICAM-1 and LFA-1 in the kidney of PSGN patients, and these findings were more pronounced in early biopsies; adhesion molecules are probably involved in the inflammatory infiltration of this disease.

Co-engagement of CD3 with LFA-1 or ICAM-1 adhesion molecules enhances the frequency of activation of single murine CD4+ and CD8+ T cells and induces synthesis of IL-3 and IFN-gamma but not IL-4 or IL-6.

Interaction between the cell adhesion molecules lymphocyte function-associated antigen-1 (LFA-1) and intercellular adhesion molecule-1 (ICAM-1) augments T cell activation by increasing the avidity of T cell/antigen-presenting cell (APC) binding. To examine whether LFA-1 and ICAM-1 can also contribute to T cell activation in the absence of APCs, single murine CD4+ and CD8+ T cells were cultured with IL-2 and immobilized antibodies to CD3, CD4 or CD8, and LFA-1 or ICAM-1. The combination of anti-CD3, anti-CD4/CD8, and IL-2 stimulated approximately 20% of CD4+ cells and 30% of CD8+ cells to proliferate. Inclusion of anti-ICAM-1 antibody increased these frequencies to 30 and 40% respectively. Maximum activation frequencies were obtained with the combination of anti-CD3, anti-CD4/CD8, and anti-LFA-1 which stimulated cell division by approximately 40% of single CD4+ cells and at least 60% of single CD8+ cells. Under these conditions, 30-40% of the resultant CD4+ clones and greater than 90% of CD8+ clones secreted IL-3 and IFN-gamma. In addition to responding at higher frequencies that CD4+ cells, CD8+ cells formed larger clones which produced 4-fold higher levels of both cytokines. Although the expression of IL-2, IL-3, IFN-gamma, granulocyte-macrophage colony stimulating factor and tumor necrosis factor alpha could be detected in CD4+ and CD8+ clones at the mRNA level following reverse transcription and polymerase chain reaction amplification, neither the secreted nor mRNA expression of IL-4 or IL-6 was detected in any of the tested clones. It is concluded that co-stimulation of T cells via LFA-1 or ICAM-1 can enhance T cell receptor-dependent activation in the absence of accessory cells and that this mode of stimulation leads to the expression of a restricted range of cytokine genes.