Abnormal Expression of BTLA and CTLA-4 Immune Checkpoint Molecules in Chronic Lymphocytic Leukemia Patients.

Chronic lymphocytic leukemia (CLL) is characterized by the peripheral accumulation of neoplastic B cells and is frequently complicated by the systemic immunosuppression associated with an impairment in B and T lymphocyte activation. We hypothesized that the expression of immune checkpoint suppressors B and T lymphocyte attenuator (BTLA) and cytotoxic T lymphocyte antigen (CTLA-4) is disturbed in both lymphocyte subpopulations in CLL. The expression of CTLA-4 and BTLA mRNA was determined by real-time PCR, while CTLA-4 protein expression (surface or intracellular) was estimated in BTLA+ lymphocytes by flow cytometry. In CLL patients, we observed a higher gene transcript level of BTLA and CTLA-4 than in healthy individuals in both freshly isolated and PMA stimulated B and T cells. Remarkably, lower amounts of both inhibitory proteins were found in peripheral blood (PB) CLL B cells, whereas normal BTLA and elevated CTLA-4 were found in T cells. Consistently, there was a prevalence of CTLA-4+ cells within circulating BTLA+ T cells cells of patients confronting PB healthy cells. After in vitro stimulation, the only change found in CLL patients was a decrease in BTLA expression in B and T lymphocytes. In contrast, healthy lymphocytes responded more vigorously as regards the BTLA and CTLA expression with substantially higher frequency of CD69+ cells under the stimulating condition compared to corresponding cells from the CLL group. Our results indicate that CLL development is associated with the affected expression of BTLA and CTLA-4 checkpoint receptors in PB and its impaired expression might be associated with lowering of the threshold for B cell activation and proliferation, while upregulated CTLA-4 expression in CLL peripheral BTLA+ T cells may contribute to suppressed T cell effector functions. This hypothesis needs to be validated in future studies, which would allow us to explain how the increased or decreased expression of these molecules affects the cell function.

CTLA-4 and CD28 genes' polymorphisms and renal cell carcinoma susceptibility in the Polish population--a prospective study.

Polymorphisms in co-stimulatory genes are associated with susceptibility to several malignances such as breast cancer, cervical cancer and chronic lymphocytic leukemia, but have been scarcely investigated in renal cell cancer (RCC). A total of 310 RCC patients and 518 controls were genotyped for single-nucleotide polymorphisms (SNPs) in the CTLA-4 and CD28 genes: CTLA-4c.49A>G (rs231775), CTLA-4g.319C>T (rs5742909), CTLA-4g.*6230G>A (CT60; rs3087243), CTLA-4g.*10223G>T (Jo31; rs11571302), CD28c.17+3T>C (rs3116496) and CD28c.-1042G>A (rs3181098). The distribution of the alleles, genotypes and haplotypes in the CTLA-4 and CD28 genes were similar in the RCC patients and in the controls. However, among the patients with a clear cell RCC (CCRCC), the G allele carriers of CT60 and Jo31 SNPs were overrepresented, and the overrepresentation became significant for the carriers of CT60[G] allele in CCRCC patients with necrosis in the primary tumor (P = 0.046). The CTLA-4c.49A>G[A]/CTLA-4g.319C>T[C]/CT60[A]/Jo31[T]/CD28c.17+3T>C[T]/ CD28c.1042G>A[G] haplotype was associated with an approximately threefold increased risk of primary tumor necrosis in CCRCC patients (P corrected = 0.0000007) and with the advanced stage of disease (IV) (P corrected = 0.001). When stratified by gender, CD28c.-1042G>A[GG] genotype was more frequent in the female CCRCC patients compared with healthy women (P = 0.042). Polymorphisms in the CTLA-4 and CD28 genes, in particular considered together as haplotypes, were associated with increased risk of CCRCC, especially with necrosis and with the advanced stage of disease. The CD28c.-1042G>A SNP modulates the risk of CCRCC in women. These findings indicate that the associations of the CTLA-4 and CD28 polymorphisms with the risk of renal cancer are worth further study in a larger group of patients.

Polymorphisms in genes of the BAFF/APRIL system may constitute risk factors of B-CLL--a preliminary study on a Polish population.

The association of single-nucleotide polymorphisms (SNPs) of B-cell activating factor (BAFF)/a proliferation-inducing ligand (APRIL) system with B-cell chronic lymphocytic leukemia (B-CLL) have been suggested, therefore, we investigated 20 SNPs of BAFF, APRIL, BAFF-R, transmembrane activator and calcium modulator and cyclophilin-ligand interactor (TACI), B-cell maturation antigen (BCMA) genes and the risk and outcome of B-CLL in 187 patients and 296 healthy subjects as well as ligand-receptor gene × gene interactions. Although the obtained P-values for all 20 SNPs did not reach statistical significance for this study (α = 0.003), the high value of the global chi-squared statistic (χ(2) df = 38 = 52.65; P = 0.0586), and obtained values of odds ratio indicate that rs9514828 (BAFF), rs3803800 (APRIL) and rs4985726 (TACI) may be associated with the risk of B-CLL. We observed that the B-CLL patients with the genotype rs9514828CT/rs11570136AA were diagnosed with the disease 12 years later than the whole group of patients in this study.

16(th) IHIW: population global distribution of killer immunoglobulin-like receptor (KIR) and ligands.

In the last fifteen years, published reports have described KIR gene-content frequency distributions in more than 120 populations worldwide. However, there have been limited studies examining these data in aggregate to detect overall patterns of variation at regional and global levels. Here, we present a summary of the collection of KIR gene-content data for 105 worldwide populations collected as part of the 15th and 16th International Histocompatibility and Immunogenetics Workshops, and preliminary results for data analysis.

KIR/HLA gene combinations influence susceptibility to B-cell chronic lymphocytic leukemia and the clinical course of disease.

The aim of this study was to analyze the association between gene polymorphisms of killer-cell immunoglobulin-like receptors (KIRs) and their human leukocyte antigen (HLA) ligands and susceptibility to B-cell chronic lymphocytic leukemia (B-CLL) and the clinical course of disease. The distribution of individual KIR genes in 197 B-CLL patients and 200 controls was similar, except for a tendency for lower frequencies of the KIR2DS3 and KIR2DL5 genes among B-CLL patients (26.9% vs 35.5%, P = 0.06, 46.2% vs 55.5%, P = 0.06). The associations between KIR2DS3 and B-CLL reached statistical significance in women (P = 0.05). Moreover, we found a trend toward a lower frequency of genotypes with the presence of five or six activating KIR genes in B-CLL patients compared to controls (20.8% vs 29.0%, P = 0.06), and a significantly higher frequency of individuals possessing genotypes with a prevalence of inhibitory over activating KIR genes (ratio < 0.71) among B-CLL patients (P = 0.04). The HLA-Bw4 specificity was significantly reduced among B-CLL patients (48.7% vs 63.0%, P = 0.005), which resulted from a decreased frequency of HLA-Bw4(Thr80) (21.6% vs 32.0%, P = 0.02). Moreover, among HLA-Bw4-positive individuals, progression-free survival (PFS) tended to be higher in the presence of KIR3DS1 (77% ± 9% vs 39% ± 13%, P = 0.07). However, in B-CLL patients, the presence of HLA-C2 was associated with decreased PFS (49% ± 9% vs 75% ± 7%, P = 0.02), and among HLA-C2-positive patients, the probability of PFS was significantly reduced in the absence of KIR2DS1 (34% ± 11% vs 77% ± 7%, P = 0.007). Our results indicate that the pattern of inhibitory/activating KIR genes, together with their HLA ligands, is associated with susceptibility to B-CLL and affects the clinical course of this disease.

Association studies of CTLA-4, CD28, and ICOS gene polymorphisms with B-cell chronic lymphocytic leukemia in the Polish population.

Abnormal expression of the costimulatory molecules cytotoxic T-lymphocyte antigen 4 (CTLA-4), CD28, and inducible co-stimulator (ICOS) leads to disturbances of immune response and an increased risk of cancer. An extended study was undertaken to evaluate the association among the polymorphisms CTLA-4c.49A>G, CTLA-4g.319C>T, CTLA-4g.*642AT(8_33), CD28c.17+3T>C, and ICOSc.1554+4GT(8_15) and susceptibility to B-cell chronic lymphocytic leukemia (B-CLL) in the Polish population. The study revealed increased frequency of the CTLA-4g.319C>T [T] allele and the CTLA-4g.319C>T [T] phenotype in B-CLL patients compared with healthy controls (p = 0.003, odds ratio [OR] = 1.73; and p = 0.009, OR = 1.74, respectively). The presence of the CD28c.17+3T>C [C] allele and the CD28c.17+3T>C [C] phenotype increased the OR of B-CLL to 1.59 (p = 0.007) and 1.74 (p = 0.007), respectively. Either CTLA-4g.319C>T or CD28c.17+3T>C was associated with time to Rai stage progression. The distributions of the alleles and genotypes of the ICOS gene significantly differed between patients and controls (p = 0.0009 and p = 0.006, respectively). Individuals possessing short alleles were 2.02 times more prone to B-CLL than others (p = 0.001), whereas carriers of long alleles were protected from B-CLL (p = 0.02, OR = 0.62). The haplotype association study and multivariate analysis confirmed the association of CTLA-4g.319C>T and ICOSc.1554+4GT(8_15) gene polymorphisms with B-CLL. The polymorphic sites CTLA-4c.49A>G and CTLA-4g.*642AT(8_33) did not correlate with B-CLL. Our results are the first in the literature to report that gene polymorphism of the costimulatory molecules CTLA-4, CD28, and ICOS contributes to susceptibility to B-CLL.

2'-deoxy-2'-fluoro-beta-D-arabinonucleic acid (2'F-ANA) modified oligonucleotides (ON) effect highly efficient, and persistent, gene silencing.

To be effective in vivo, antisense oligonucleotides (AS ON) should be nuclease resistant, form stable ON/RNA duplexes and support ribonuclease H mediated heteroduplex cleavage, all with negligible non-specific effects on cell function. We report herein that AS ONs containing a 2'-deoxy-2'-fluoro-beta-D-arabinonucleic acid (2'F-ANA) sugar modification not only meet these criteria, but have the added advantage of maintaining high intracellular concentrations for prolonged periods of time which appears to promote longer term gene silencing. To demonstrate this, we targeted the c-MYB protooncogene's mRNA in human leukemia cells with fully phosphorothioated 2'F-ANA-DNA chimeras (PS-2'FANA-DNA) and compared their gene silencing efficiency with AS ON containing unmodified nucleosides (PS-DNA). When delivered by nucleofection, chemically modified ON of both types effected a >90% knockdown of c-MYB mRNA and protein expression, but the PS-2'F-ANA-DNA were able to accomplish this at 20% of the dose of the PS-DNA, and in contrast to the PS-AS DNA, their silencing effect was still present after 4 days after a single administration. Therefore, our data demonstrate that PS-2'F-ANA-DNA chimeras are efficient gene silencing molecules, and suggest that they could have significant therapeutic potential.

Lack of IFN-gamma 2/2 homozygous genotype independently of recipient age and intensity of conditioning regimen influences the risk of aGVHD manifestation after HLA-matched sibling haematopoietic stem cell transplantation.

A total of 110 patients (71 adults and 39 children) who received allogeneic haematopoietic stem cell transplantation from HLA-matched sibling donors were studied for the incidence of acute graft-versus-host disease (aGvHD) in relation to IFN-gamma gene microsatellite polymorphism. A strong tendency was observed towards the lower incidence of grades II-IV aGvHD in patients having an IFN-gamma 2/2 genotype as compared to the recipients with other IFN-gamma genotypes (0.12 vs 0.33, P=0.06). This relationship was independent of the intensity of conditioning regimen and diagnosis. IFN-gamma polymorphic features, together with other clinical and biological factors (patient's age, donor-recipient gender, diagnosis, conditioning regimen, transplant material and GvHD prophylaxis), were subjected to multivariate analysis for aGvHD manifestation in order to exclude indirect association of the IFN-gamma 2/2 genotype. In multivariate analysis, myeloablative therapy (OR=11.462, P=0.013), recipient age (OR=4.896, P=0.009) and lack of IFN-gamma 2/2 genotype (OR=4.311, P=0.048) were found to significantly contribute to the development of grade II-IV aGvHD, while type of GvHD prophylaxis showed less-strong influence (OR=2.963, P=0.066). Thus, it appeared that the IFN-gamma 2/2 genotype constituted an independent and protective factor associated with a decreased risk of grade II-IV aGvHD. However, this genotype was not found to be associated with the risk of cGvHD or survival.

IL-6 production in ovarian carcinoma is associated with histiotype and biological characteristics of the tumour and influences local immunity.

The presence of interleukin (IL)-6 in peritoneal carcinomatous fluid (PCF) and its effect on immune cells composition in PCF in patients with advanced ovarian carcinoma was studied. In 21 out of 30 ovarian carcinoma patients, PCF IL-6 levels were found to exceed those seen in PCFs of patients with gastrointestinal cancer. IL-6 activity was higher in serous/mucinous than in endometrioid and undifferentiated ovarian carcinoma PCF (P = 0.05). Ovarian carcinoma PCF IL-6 activities were correlated with serum C-reactive protein levels (r = 0.65, P = 0.0000, n = 25). Ovarian carcinoma PCF leucocyte profile differed from that in blood with respect to: (i) lower percentage of NK and CD8+ and (ii) higher percentage of B and CD45RO+, CD14+ and HLA-DR+ cells. The proportions of CD45RO+ in blood were correlated with IL-6 levels in PCF. Corresponding to PCF ovarian carcinoma tumours were stained for the presence of Ki-67 antigen and p53. The highest proportions of Ki-67+ cells and cells showing accumulation of p53 were seen in undifferentiated tumours. A low grade of p53 staining was seen in tumours associated with high IL-6 levels in PCF. It was evident that IL-6 production (i) depended on the histiotype of the tumour, (ii) influenced the local immune system in favour of accumulation of B, and T memory cells, and (iii) was higher in patients lacking p53 accumulation.

Cytokines, adhesion molecules (E-selectin and VCAM-1) and graft-versus-host disease.

Analysis of skin biopsy specimens for the presence of adhesion molecules, composition of cellular infiltrates, Ki-67 antigen expression, and examination of serum for interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) levels, wes performed in patients after allogeneic bone marrow transplantation (alloBMT), to study the pathomechanism of acute graft-versus-host disease (aGvHD). It was found that: 1) early hematological recovery constitutes a risk factor for grade IV GvHD, 2) vascular cell adhesion molecule-1 (VCAM-1) is present in the matrix organizing the cells in the bone marrow and in aGvHD infiltrates, 3) HLA DR antigens aberrant expression in epithelial cells, as well as 4) strong expression of Ki-67 is seen in early stages of aGvHD. These immunopathomorfological lesions are cytokine-dependent. High levels of IL-6 and TNF-alpha were found in sera of patients affected with the aGvHD process and infectious complications. An increase of IL-6 in the course of aGvHD is a sign of poor prognosis. These data support the notion that cytokines facilitate the cell accumulation at the site of aGvHD at the beginning of this process and again, at the final stage of the disease, cytokines high levels are associated with the organ damage.