[Expression of CD58 in childhood B-lineage acute lymphoblastic leukemia and its feasibility in minimal residual disease detection].

OBJECTIVE: To measure the expression of lymphocyte function-associated antigen-3 (CD58) in childhood B-lineage acute lymphoblastic leukemia (B-ALL) and to explore the feasibility of CD58 as an indicator for minimal residual disease (MRD) detection in childhood B-ALL. METHODS: Eighty-seven children diagnosed with B-ALL between January 2014 and September 2014 were enrolled, and 20 hospitalized children who had no tumor or blood disease and had normal bone marrow cell morphology served as the control group. The expression features of CD58 in bone marrow samples from the two groups (at diagnosis, on day 15 of induction chemotherapy) were analyzed by four-color flow cytometry (FCM). Quantitative real-time polymerase chain reaction (qRT-PCR) and FCM were used to detect MRD in B-ALL patients on day 33 of induction chemotherapy. RESULTS: The mean fluorescence intensity of CD58 expression in the 87 B-ALL cases (91±33) was significantly higher than that in the 20 controls (14±6) (P<0.01); CD58 was over-expressed in 44 of the B-ALL cases. In the B-ALL children, the expression of CD58 on day 15 of induction chemotherapy (105±22) was not significantly different from that at diagnosis (107±26) (P>0.05). In the 44 B-ALL patients with CD58 over-expression, FCM showed 9 MRD(+) cases and 35 MRD(-) cases, while qRT-PCR showed 11 MRD(+) cases and 33 MRD(-) cases; 42 cases (95%) showed consistent results of the two tests, so there was no significant difference between the two methods in detecting MRD (P>0.05). CONCLUSIONS: CD58 is over-expressed and stable in children with B-ALL, and it can be considered as an indicator for MRD detection in childhood B-ALL.

Clinical impact of leukemic blast heterogeneity at diagnosis in cytogenetic intermediate-risk acute myeloid leukemia.

BACKGROUND: Individual cellular heterogeneity within the acute myeloid leukemia (AML) bone marrow samples can be observed by multi parametric flow cytometry analysis (MFC) indicating that immunophenotypic screening for leukemic blast subsets may have prognostic impact. MATERIAL AND METHODS: Samples from de novo AML patients of all cytogenetic risk groups were collected at diagnosis and subjected to MFC based on a four-color antibody panels against 33 CD membrane markers and retrospectively analyzed for the leukemia blast expression pattern and mean fluorescence intensity. Identification of the leukemic blast cells was based on right angle light scatter (SSC) and expression of CD45 and the cellular heterogeneity identified by the presence of at least two distinct subsets by any CD marker. RESULTS: Analysis of marrow samples from 86 patients with cytogenetic intermediate risk identified recurrent heterogeneous blast phenotypes for selected CD markers, three of which had prognostic impact with loss or gain of CD58, CD117, or CD14 expression. Multivariate Cox regression analysis of diagnostic variables identified poor prognostic factors: Age >55 years, presence of extramedullary disease, WHO performance score >2, a heterogeneous CD58, CD117, or CD14 expression on blast cells. Each variable added to a simple and clinical useful and MFC based prognostic score system associated to inferior survival in the intermediate risk group of AML patients. CONCLUSIONS: These observations support that leukemic blast heterogeneity detected by MFC has additional prognostic significance in de novo AML; however, the score system needs to be prospectively validated in future clinical trials before implementation.

Expression of CXCR4, VLA-1, LFA-3 and transducer of ERB in G-CSF-mobilised progenitor cells in acute myocardial infarction.

G-CSF induced mobilisation of progenitor cells is a multistep processes involving chemokines, growth factors, matrix-degrading enzymes, and cell adhesive interactions mediated by specific receptors on haematopoietic cells. This study's aim was to investigate progenitor cells mobilised during myocardial infarction after treatment with granulocyte-stimulating factor (G-CSF). In the randomised, double-blind, placebo-controlled REVIVAL-2 study, 114 patients with acute myocardial infarction were included. Five days after successful percutaneous coronary intervention patients received either 10 microg/kg G-CSF (n=56) or placebo (n=58) subcutaneously for five days. Venous blood samples were analysed on day(s) 1, 3, 5 and 7 after therapy, and progenitor cell mobilisation and surface expression of VLA-4, LFA-1 and CXCR-4 was measured on circulating progenitor cells using flow cytometry. G-CSF induced a significant increase in circulating progenitor cells (72 +/- 20 cells/microl vs. 4.5 +/- 0.8 cells/microl, p<0.05). Surface expression of LFA-1, VLA-4 and CXCR4 on progenitor cells was decreased by 44%, 49% and 60% after G-CSF as compared to placebo (p<0.05). In accordance, mRNA expression of CXCR4 was reduced. Moreover, anti-proliferative transducer of ERB (TOB) mRNA was decreased, suggesting an increased proliferative potential of the mobilised progenitor cells. Decreased expression of adhesion and chemokine receptors on G-CSF mobilised progenitor cells in acute myocardial infarction may alter the homing capacity of circulating cells to the myocardium.

Different inflammatory cell pattern and macrophage phenotype in chronic obstructive pulmonary disease patients, smokers and non-smokers.

Smokers exhibit airway inflammation and increased number of alveolar macrophages (AM), but not all develop chronic obstructive pulmonary disease (COPD). We hypothesized that AMs in COPD patients have an altered functional capacity mirrored in a different phenotype. Sixteen steroid-naive COPD patients [forced expiratory volume in 1 s (FEV(1)) < 70% of predicted] underwent bronchoalveolar lavage (BAL). Age- and smoking-matched non-obstructive smokers (n = 10) and healthy non-smokers (n = 9) served as controls. Nine COPD patients had a BAL cell yield sufficient for flow cytometry analysis, where expression of AM cell surface markers reflecting various functions was determined. AMs from COPD patients showed decreased expression of CD86 (co-stimulation) and CD11a (adhesion) compared to smokers' AMs (P < 0.05). Furthermore, smokers' AMs showed lower (P < 0.05) expression of CD11a compared to non-smokers. AM expression of CD11c was higher in the COPD and smokers groups compared to non-smokers (P < 0.05). The expression of CD54 (adhesion) was lower in smokers' AMs compared to non-smokers (P < 0.05), whereas CD16 was lower (P < 0.05) in COPD patients compared to non-smokers. The AM expression of CD11b, CD14, CD58, CD71, CD80 and human leucocyte antigen (HLA) Class II did not differ between the three groups. The AM phenotype is altered in COPD and further research may develop disease markers. The lower AM expression of CD86 and CD11a in COPD implies a reduced antigen-presenting function. Some alterations were found in smokers compared to non-smokers, thus indicating that changes in AM phenotype may be associated with smoking per se. The functional relevance of our findings remains to be elucidated.

[Prognostic significance of lymphocyte function associated anti-gen-3 (CD58) in childhood B cell-acute lymphocytic leukemia].

This study was aimed to investigate the value of CD58 in evaluation of early therapeutic effect on childhood B-ALL. The expression features of CD58 in 135 cases of childhood B-ALL were analyzed by four-color flow cytometry; MRD detection protocol for B-ALL using CD58/CD10/CD34/CD19 combination was established; the correlation between the expression features of CD58 and MRD detection was analyzed for the early therapeutic response in childhood B-ALL. The results showed that the mean value of CD58 MFI in 135 cases of B-ALL was 113.08 +/- 63.33, which was significantly higher than that in 15 cases of normal bone marrow controls (14.68 +/- 5.26, P < 0.01). In addition, CD58 was over expressed in 51.9% (70/135) of B-ALL patients, indicating that CD58 could be an effective marker in MRD detection. The CD58/CD10/CD34/CD19 was the second most effective combination next to TdT/CD10/CD34/CD19 in B-ALL MRD detection with flow cytometry. Meanwhile, the positive rate of MRD detection by flow cytometry was significantly lower in CD58 over expression group (P < 0.05). It is concluded that CD58 may be used as an indicator for detection of MRD in B-ALL patients, which would enrich the combination of MRD detection. The CD58 over expression may be considered as a marker of a favorable prognosis in childhood B-ALL.

Changes in soluble adhesion molecules in gingival crevicular fluid following periodontal surgery.

BACKGROUND: Inflammation of periodontal tissues during postoperative wound healing is mediated by cell surface adhesion molecules. Soluble forms of these antigens have also been identified and shown to be important in immunoregulatory processes, but have previously not been investigated during periodontal repair and regeneration. The present study has examined the presence and possible changes in soluble intercellular adhesion molecule-1 (sICAM-1; CD54) and lymphocyte function-associated antigen-3 (sLFA-3; CD58) in gingival crevical fluid (GCF) following periodontal surgery. METHODS: GCF samples were collected from four groups: 1) a guided tissue regeneration (GTR) test; 2) a GTR control, at least one complete tooth unit away from the periodontal defect; 3) a conventional flap (CF) surgery; and 4) a crown lengthening (CL). Sandwich enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of sICAM-1 and sLFA-3 in the GCF samples. RESULTS: A marked increase in GCF volumes was found in all sites after surgery, although a persistent increase was associated only with the period of membrane retention at the GTR test sites. In addition, sICAM-1 and sLFA-3 were found in the GCF of healthy as well as diseased sites prior to treatment and the total amounts of both increased transiently following surgical intervention, especially sLFA-3. However, the concentrations of these GCF components, particularly sICAM-1, tended to decrease. CONCLUSIONS: The temporal decrease in the concentration of sICAM-1 and sLFA-3 in GCF may serve to enhance inflammatory reactions at surgically-treated periodontal sites, thereby limiting repair and regeneration in the periodontium. These soluble adhesion molecules may thereby be of potential therapeutic value and might also be useful markers for monitoring periodontal wound healing.

CD58 expression decreases as nonmalignant B cells mature in bone marrow and is frequently overexpressed in adult and pediatric precursor B-cell acute lymphoblastic leukemia.

We used flow cytometry to determine the CD58 expression on nonmalignant B cells at different stages of maturation in the bone marrow and compared it with that of blasts in adult and pediatric precursor B-cell acute lymphoblastic leukemia (B-ALL). The mean fluorescence intensity (MFI) of CD58 expression decreased significantly as nonmalignant B cells differentiated in the bone marrow from an early to a mature stage. Few nonneoplastic B cells at a mid or mature stage of development expressed CD58 MFI values comparable to those seen in leukemic cases. Early-stage nonneoplastic B-cell precursors expressed relatively higher CD58 levels, which frequently overlapped with the variable level of CD58 expression observed among leukemic blasts. As a group, however, the malignant precursor B-ALL cells showed significantly higher expression of CD58 than nonmalignant B-cell populations at any maturational stage. These findings support the potential usefulness of CD58 expression in the diagnosis and monitoring of precursor B-ALL, but only when blasts express high levels of CD58.

Expression of CD58 in normal, regenerating and leukemic bone marrow B cells: implications for the detection of minimal residual disease in acute lymphocytic leukemia.

BACKGROUND AND OBJECTIVES: CD58, a member of the Ig superfamily, is expressed by hematopoietic and non- hematopoietic cells. It has been demonstrated to be over-expressed in precursor-B acute lymphoblastic leukemia (ALL) blasts when compared to in their normal counterparts, suggesting its potential use in the detection of minimal residual disease (MRD) by flow cytometry (FC). To assess the reliability and accuracy of CD58 for this purpose, we studied its expression in a large series of normal and ALL bone marrow (BM) samples using quantitative FC. DESIGN AND METHODS: We studied 180 precursor-B ALL BM samples at diagnosis (8 pro-B, 164 early-B, 8 mature-B ALL) and 123 follow-up BM samples (n=54 at day +15 and n=69 at day +78), as well as 51 normal BM samples and 7 regenerating BM samples from patients with T-ALL at week 12. We used four-color quantitative FC, focusing analysis on CD58 expression. In follow-up samples from day +78, the MRD level was simultaneously evaluated by real time quantitative polymerase chain reaction (RQ-PCR) amplification of antigen receptor genes. RESULTS: CD58 expression was significantly higher in ALL blasts than in normal B lymphocytes, while no significant differences between regenerating and normal B lymphocytes were observed. CD58 was expressed in 99.4% of the precursor-B ALL cases and 93.5% of these showed over-expression compared to normal. No significant modulation of CD58 expression during remission induction therapy was noted. Finally, 66 (95.6%) of 69 BM samples simultaneously analyzed using both FC and RQ-PCR at day +78 showed concordant results regarding MRD. INTERPRETATION AND CONCLUSIONS: Our results confirm and further evidence the role of CD58 in the diagnosis and monitoring of precursor-B ALL. In particular, we demonstrated its stability and accuracy in MRD detection at clinically relevant time points. These findings indicate that CD58 is a powerful tool for MRD detection in precursor-B ALL.

Lipopolysaccharide signal transduction in oral keratinocytes--involvement of CD59 but not CD14.

There are a variety of dermal and mucosal lesions involving keratinocytes. We examined here the signal transduction of lipopolysaccharide (LPS) in oral keratinocytes. Oral keratinocytes did not express CD14, but expression of CD58 and CD59 was observed by flow cytometry and reverse transcription-PCR. The binding between LPS and keratinocytes was strongly inhibited by pretreatment of keratinocytes with anti-CD59 monoclonal antibody (mAb) or phosphatidylinositol-specific phospholipase C (PI-PLC) but was not inhibited by anti-CD14 or anti-CD58 mAb. In LPS-treated keratinocytes, nuclear translocation of nuclear factor-kappa B (NF-kappaB) was induced and generation of granulocyte-macrophage colony-stimulating factor, interleukin-6 and tumour necrosis factor-alpha was enhanced. These upregulations in nuclear translocation of NF-kappaB and cytokine generation were not suppressed by anti-CD14 mAb or anti-CD58 mAb but were suppressed by anti-CD59 mAb and PI-PLC. Moreover, the transfection of CD59 antisense oligonucleotide into keratinocytes markedly suppressed LPS-induced nuclear translocation of NF-kappaB and cytokine generation. These results indicate that, through CD59, the LPS signal is transduced into the nucleus via NF-kappaB activation inducing cytokine generation, which may be involved in dermal and mucosal inflammatory diseases.

T-cell clones can be rendered specific for CD19: toward the selective augmentation of the graft-versus-B-lineage leukemia effect.

Relapse of B-lineage acute lymphoblastic leukemia (B-ALL) after allogeneic hematopoietic stem cell transplantation (HSCT) commonly results from the failure of a graft-versus-leukemia (GVL) effect to eradicate minimal residual disease. Augmenting the GVL effect by the adoptive transfer of donor-derived B-ALL-specific T-cell clones is a conceptually attractive strategy to decrease relapse rates without exacerbating graft-versus-host disease (GVHD). Toward this end, we investigated whether a genetic engineering approach could render CD8(+) cytotoxic T lymphocytes (CTLs) specific for tumor cells that express the B-cell lineage cell surface molecule CD19. This was accomplished by the genetic modification of CTLs to express a chimeric immunoreceptor composed of a CD19-specific single-chain immunoglobulin extracellular targeting domain fused to a CD3-zeta intracellular signaling domain. CD19-redirected CTL clones display potent CD19-specific lytic activity and chimeric immunoreceptor-regulated cytokine production and proliferation. Because B-ALL cells can evade T-cell/natural killer- cell recognition by down-regulation of cell surface accessory molecules that participate in the formation of a functional immunologic synapse, we compared the CD19-specific effector function of genetically modified CD8(+) CTLs toward CD19(+) cells with disparate levels of intercellular adhesion molecule 1 (ICAM-1), leukocyte function-associated antigen 1 (LFA-1), and LFA-3. We observed that recognition of B-lineage tumor lines by CD19-specific CTLs was not impaired by low levels of ICAM-1, LFA-1, and LFA-3 cell surface expression, a functional attribute that is likely a consequence of our high-affinity CD19-specific chimeric immunoreceptor. Furthermore, the CD19-specific CTLs could lyse primary B-ALL blasts. These preclinical observations form the basis for implementing clinical trials using donor-derived CD19-specific T-cell clones to treat or prevent relapse of B-ALL after allogeneic HSCT.

Impact of human bladder cancer cell architecture on autologous T-lymphocyte activation.

To investigate the influence of tumor cell architecture on T-cell activation, we used an autologous human model based on 2 bladder tumor cell lines as targets for cytotoxic tumor-infiltrating lymphocytes (TILs). These tumor cell lines were grown in vitro as either standard 2-dimensional (2D) monolayers or 3-dimensional (3D) spheroids. T-cell activation was determined by measuring the production of three major cytokines (tumor necrosis factor, granulocyte/macrophage colony-stimulating factor and interferon-gamma), known to be secreted by most activated TILs. Changes in the architecture of target cells from 2D to 3D induced a dramatic decrease in their capacity for stimulating TILs. Interestingly, neither TIL infiltration nor MHC class I, B7.1 costimulatory or lymphocyte function-associated factor-3 adhesion molecule downregulation played a major role in this decrease. These findings demonstrate that tumor architecture has a major impact on T-cell activation and might be implicated in the escape of tumor cells from the immune system.

Identification of novel markers for monitoring minimal residual disease in acute lymphoblastic leukemia.

To identify new markers of minimal residual disease (MRD) in B-lineage acute lymphoblastic leukemia (ALL), gene expression of leukemic cells obtained from 4 patients with newly diagnosed ALL was compared with that of normal CD19(+)CD10(+) B-cell progenitors obtained from 2 healthy donors. By cDNA array analysis, 334 of 4132 genes studied were expressed 1.5- to 5.8-fold higher in leukemic cells relative to both normal samples; 238 of these genes were also overexpressed in the leukemic cell line RS4;11. Nine genes were selected among the 274 overexpressed in at least 2 leukemic samples, and expression of the encoded proteins was measured by flow cytometry. Two proteins (caldesmon and myeloid nuclear differentiation antigen) were only weakly expressed in leukemic cells despite strong hybridization signals in the array. By contrast, 7 proteins (CD58, creatine kinase B, ninjurin1, Ref1, calpastatin, HDJ-2, and annexin VI) were expressed in B-lineage ALL cells at higher levels than in normal CD19(+)CD10(+) B-cell progenitors (P <.05 in all comparisons). CD58 was chosen for further analysis because of its abundant and prevalent overexpression. An anti-CD58 antibody identified residual leukemic cells (0.01% to 1.13%; median, 0.03%) in 9 of 104 bone marrow samples from children with ALL in clinical remission. MRD estimates by CD58 staining correlated well with those of polymerase chain reaction amplification of immunoglobulin genes. These results indicate that studies of gene expression with cDNA arrays can aid the discovery of leukemia markers. (Blood. 2001;97:2115-2120)

Expression of adhesion and activation molecules in human buccal epithelial cell lines and normal human buccal epithelium in situ.

An in vitro culture system may be used to analyse interactions between T cells and epithelium. We have analysed two human buccal squamous epithelial cell lines: SqCC/Y1, derived from a buccal carcinoma, and SVpgC2a, an SV-transformed healthy buccal squamous epithelium. Under serum-free culture conditions, the cell lines resemble normal buccal squamous epithelium in situ in their expression of MHC class I, CD29 (beta1 integrin), CD40, CD44, CD54 (ICAM-1), CD58 (LFA-3), CD95 (Fas), and E-cadherin. Furthermore, when the SVpgC2a cell line was treated with T-cell derived cytokines, upregulation of CD40 expression was observed when the cells were treated with IL-4, whereas IFN-gamma caused upregulation in expression of CD40, CD54 and MHC class II. These buccal squamous epithelial cell lines, therefore, provide a good tool for analysing interactions between epithelium and T cells in vitro.

VLA-4/CD49d downregulated on primed T lymphocytes during interferon-beta therapy in multiple sclerosis.

Effects on adhesion molecules of immune cells might contribute to the mode of action of interferon-beta (IFN-beta) in multiple sclerosis (MS). We have serially monitored the cell surface expression of integrins CD49d (VLA-4) and CD11a (LFA-1) on fresh T lymphocyte subpopulations from 5 MS patients monthly for 2 months prior to treatment and for 3 months on treatment with IFN-beta1b. In parallel, we assessed inflammatory disease activity by monthly contrast-enhanced magnetic resonance imaging (MRI). IFN-beta treatment specifically downregulated CD49d expression on CD8+ and CD4+/CD45RO+ 'memory' T lymphocytes and differentially modulated the proportion of CD4+, CD8+ and CD27+ T cells. These effects may play an important role in the reduction of central nervous system cell trafficking and inflammation in MS.

Expression of accessory molecules for T-cell activation in peripheral nerve of patients with CIDP and vasculitic neuropathy.

Vasculitic neuropathy and chronic inflammatory demyelinating polyneuropathy (CIDP) are neuropathies characterized by a T-lymphocyte infiltrate in the peripheral nerves. The microenvironment in which these T cells become activated, and the molecules and cells that play a role in this process are incompletely understood. Using immunohistochemical analysis, we studied the effect of the presence of adhesion, costimulatory and antigen-presenting molecules on different cell types as a precondition for local T-cell activation in human sural nerve biopsies of seven patients with CIDP, three patients with vasculitic neuropathy and three healthy controls. In biopsies from CIDP and vasculitic neuropathy patients, but not in those from healthy controls, Schwann cells expressed the adhesion/T-cell stimulatory molecule CD58 (LFA-3). The CD58 molecule was also present on endothelial cells of all vasculitic neuropathy patients and one CIDP patient. In biopsies from normal controls and patients, CD54 (ICAM-1) expression was detectable on microvascular endothelial cells. In addition, expression of the costimulatory molecule CD86 was detected on vascular tissue in patients with vasculitic neuropathy. Although macrophages were always present in all subjects, expression of the major histocompatibility complex (MHC)-like molecule CD1a by macrophages was restricted to biopsies from two CIDP patients and one vasculitic neuropathy patient. Unexpectedly, Schwann cells of a single vasculitis patient strongly expressed CD1b, a molecule involved in the presentation of self-glycolipids to T cells. Schwann cells in biopsies from patients and normal controls expressed high levels of the invariant chain, CD74, a molecule involved in the intracellular sorting of MHC class II molecules. There was no evidence for the presence of dendritic cells in sural nerve biopsies. These findings support a model in which T-cell activation can be initiated and/or perpetuated locally in sural nerve biopsies of patients with CIDP and vasculitic neuropathy, and predict an important role for Schwann cells and endothelial cells.

The role of T cell costimulation by CD80 in the initiation and maintenance of the immune response to human leukemia.

Most human myeloid leukemias express both class I and class II HLA and it has been postulated that leukemia-associated peptides are presented by those molecules. It is possible, however, that leukemia cells escape the immune surveillance by lacking expression of "costimulatory" molecules required for activating the immune response. Human erythroleukemia line (HEL) has been the subject of previous detailed studies demonstrating surface expression of bona fide HLA molecules but inability to stimulate allogeneic response of proliferative or cytolytic T cells. We found that an HLA-DR+ subclone (HEL-DR+) expresses LFA-1, LFA-3, ICAM-1, ICAM-3, but neither CD80 nor CD86 on the surface. Transfection of CD80 cDNA into HEL-DR+ cells induced the allogeneic response of purified T cells from both cord blood and peripheral blood of adult donors, demonstrating that CD80 expression could lead to accessory cell-independent activation of naive T cells. Priming allogeneic peripheral blood T cells by HEL-DR+/CD80+ also lead to generation of cytotoxic T lymphocytes that lysed both HEL-DR+/CD80+ and wild type HEL-DR+ equally well, confirming CD80 expression is required only in the CTL induction phase but not in the CTL effector phase. We established and maintained alloproliferative T cell clones from adult blood by stimulation with the HEL-DR+/CD80+ line. The clones could respond not only to HEL-DR+/CD80+ line but also to the HEL-DR+ line; however, the proliferative response to HEL-DR+/CD80+ was amplified and sustained compared to the short-lived response to wild type HEL-DR+ cells. Therefore, expression of CD80 by HEL-DR+ cells was determinant both to initiate and sustain the T cell response. These experiments support the hypothesis that lack of expression of "costimulatory" molecules for T cells contributes to leukemia escape from immune surveillance, and provide preliminary data for the use of CD80 transfection in the immunotherapy of human leukemia.

Reduced expression of adhesion molecules and cell signaling receptors by chronic lymphocytic leukemia cells with 11q deletion.

Deletions in chromosome bands 11q22-q23 were recently shown to be one of the most frequent chromosome aberrations in B-cell chronic lymphocytic leukemia (B-CLL). Patients suffering from B-CLL with 11q deletion are characterized by extensive lymphadenopathy, rapid disease progression, and short survival times. Phenotypic and functional characteristics of B-CLL cells with 11q deletion that may help to explain the pathophysiology of this entity are yet unknown. In the present study, B-CLL cells with (n = 19) and without (n = 19) 11q deletion were analyzed for their expression of functionally relevant cell surface molecules (n = 57). B-CLL cells with 11q deletion carried significantly lower levels of the adhesion molecules CD11a/CD18 (integrin alphaL/beta2), CD11c/CD18 (integrin alphaX/beta2), CD31 (PECAM-1), CD48, and CD58 (LFA-3). Furthermore, B-CLL cells with 11q deletion expressed less the cell signaling receptors CD45 (leukocyte common antigen [LCA]), CD6, CD35 (complement receptor 1), and CD39. Reduced CD45 levels and low-level expression of CD49d correlated with decreased overall survival. B-CLL cells with or without 11q deletion did not differ in their growth fractions, expression levels of transcription factor NF-kappaB, or their response to mitogenic stimuli. Decreased levels of functionally relevant adhesion molecules and of cell signaling receptors may contribute to the pathogenesis of the subgroup of B-CLL characterized by 11q22-q23 deletion.

A lymphokine-activated killer (LAK)-resistant cell line, and low expression of adhesion molecules LFA-3 and VCAM-1 on its cell surface.

Tumor cell lines are generally killed by lymphokine-activated killer (LAK) cells. In this study, however, we report a LAK-resistant cell line, OKM-2T. The OKM-2T is an adult T-cell leukemia (ATL) cell line, and was compared to other ATL cell lines and non-ATL cell lines. The LAK cells were generated from healthy volunteers. Cell surface markers were determined by a flow cytometry test. The ATL and non-ATL cell lines were killed by the LAK cells, markedly or moderately. However, the OKM-2T was scarcely killed. The adhesion tendency of the OKM-2T to the LAK cells was preserved at the same level as that of the other cell lines, whereas the OKM-2T showed low levels of adhesion molecules CD58 (LFA-3), CD86, and CD106 (VCAM-1). We determined blocking tests using specific antibodies. Anti-CD58 blocked the LAK lysis. Anti-CD54 and anti-CD106 enhanced the blocking effect of the anti-CD58; anti-CD86 did not show such an effect. These results suggest that the low expression of CD58 in the OKM-2T may have an intimate relationship with LAK resistance, and that the low expression of CD106 may also be responsible for it, in part.