Shifts in subsets of CD8+ T-cells as evidence of immunosenescence in patients with cancers affecting the lungs: an observational case-control study.

BACKGROUND: Shifts in CD8+ T-cell subsets that are hallmarks of immunosenescence are observed in ageing and in conditions of chronic immune stimulation. Presently, there is limited documentation of such changes in lung cancer and other malignancies affecting the lungs. METHODS: Changes in CD8+ T-cell subsets, based on the expression of CD28 and CD57, were analysed in patients with various forms of cancer affecting the lungs, undergoing chemotherapy and in a control group over six months, using multi-colour flow cytometry. RESULTS: The differences between patients and controls, and the changes in the frequency of CD8+ T-cell subpopulations among lung cancer patients corresponded to those seen in immunosenescence: lower CD8-/CD8+ ratio, lower proportions of CD28+CD57- cells consisting of naïve and central memory cells, and higher proportions of senescent-enriched CD28-CD57+ cells among the lung cancer patients, with the stage IV lung cancer patients showing the most pronounced changes. Also observed was a tendency of chemotherapy to induce the formation of CD28+CD57+ cells, which, in line with the capacity of chemotherapy to induce the formation of senescent cells, might provide more evidence supporting CD28+CD57+ cells as senescent cells. CONCLUSION: Immunosenescence was present before the start of the treatment; it appeared to be pronounced in patients with advanced cases of malignancies affecting the lungs, and might not be averted by chemotherapy.

Aging-associated subpopulations of human CD8+ T-lymphocytes identified by their CD28 and CD57 phenotypes.

BACKGROUND: During organismal aging, human T-cells shift towards less functional phenotypes, often called senescent cells. As these cells have not been well characterized, we aimed to relate surface markers of human T-cell senescence with characteristics of in vitro cellular aging and to further characterize these cells. METHODS: We identified, by flow cytometry, subpopulations of CD8+ T-cells based on CD57 and CD28 expression, and tested them for some markers of cellular senescence, apoptosis, differentiation and homing. RESULTS: Elderly persons presented significantly higher proportions not only of CD28-CD57+, but also of CD28+CD57+ cells. CD28+CD57+ cells had the highest expression of p16, p21, Bcl-2, CD95, CD45RO, CCR5 and PD-1, thereby arguing in favor of a senescent phenotype. CONCLUSION: Among CD8+ T-lymphocytes, CD28+CD57+ cells represent a subset with some senescent features that are distinct from the CD28-CD57+ cells.

High natural killer cell number might identify stroke patients at risk of developing infections.

OBJECTIVE: To investigate early changes in leukocyte subsets and autonomic function as predictors of the development of poststroke infections. METHODS: We assessed the time course of leukocyte subsets in the blood of 59 patients with acute ischemic stroke. We divided the patients into 2 groups: those who developed infections during the first 7 days after stroke onset and those who did not. We measured urinary norepinephrine and epinephrine concentrations and pulse rate variability indices within 24 hours of admission. RESULTS: We found that the number of circulating natural killer (NK) cells within the first hours after stroke was higher in stroke patients who developed infections (mean 435 cells/mL; 95% confidence interval [CI] 321-588) than in stroke patients who did not develop infections (mean 236 cells/mL; 95% CI 186-300; p = 0.001). This was followed by a decrease in all lymphocyte subsets from admission to day 1, varying between 22% and 40%, which was not seen in patients without poststroke infection (mean increase varied between 2% and 23%; all p < 0.005). In the group that developed infections, pulse rate variability revealed a decreased high frequency component. These findings all remained significant after adjustment for age and stroke volume. CONCLUSIONS: High circulating NK cell count within the first hours after ischemic stroke onset followed by a drop in all lymphocyte subsets identified patients who developed infections and may be caused by a sympathovagal imbalance with sympathetic overweight. These findings need to be validated in larger studies.

Chemotherapy-induced changes and immunosenescence of CD8+ T-cells in patients with breast cancer.

BACKGROUND: Changes in sub-populations of cytotoxic (CD8+) T-cells, which are observed in aging and in conditions of chronic immune stimulation, are not well-documented in cancer. MATERIALS AND METHODS: Using flow cytometry, CD8+ T-cell subsets were analyzed in patients with breast cancer undergoing DNA-damaging chemotherapy and in an older female control group during a six-month longitudinal study, to explore shifts in CD8+ T-cells and the effect of DNA-damaging chemotherapy on different T-cell sub-populations. RESULTS: As expected, there was a consistent decrease in absolute numbers of leukocytes, lymphocytes, T-cells and CD8+ T-cells during chemotherapy in patients with cancer. Among the T-cells, there was a lower CD8-/CD8+ ratio, persisting over the six months, in patients with cancer compared to controls. The proportion of CD28-CD57+ cells also remained higher among patients with cancer throughout the sampling duration. The number of CD28+CD57- and CD28-CD5- cells decreased faster during DNA-damaging chemotherapy than CD28+CD57+ and CD28-CD57+ cells, while only CD28-CD57- cells showed a significant reconstitutive capacity after six months. CONCLUSION: Immunosenescence appeared to be pronounced in patients with breast cancer, with senescent CD8+ T-cells playing a role. The normal condition was not restored after six months of chemotherapy.

Preclinical evaluation of invariant natural killer T cells in the 5T33 multiple myeloma model.

Immunomodulators have been used in recent years to reactivate host anti-tumor immunity in several hematological malignancies. This report describes the effect of activating natural killer T (NKT) cells by α-Galactosylceramide (α-GalCer) in the 5T33MM model of multiple myeloma (MM). NKT cells are T lymphocytes, co-expressing T and NK receptors, while invariant NKT cells (iNKTs) also express a unique semi-invariant TCR α-chain. We followed iNKT numbers during the development of the disease in both 5T33MM mice and MM patients and found that their numbers dropped dramatically at the end stage of the disease, leading to a loss of total IFN-γ secretion. We furthermore observed that α-GalCer treatment significantly increased the survival of 5T33MM diseased mice. Taken together, our data demonstrate for the first time the possibility of using a preclinical murine MM model to study the effects of α-GalCer and show promising results of α-GalCer treatment in a low tumor burden setting.

Diagnostic potential of CD34+ cell antigen expression in myelodysplastic syndromes.

The World Health Organization introduced flow cytometry as an additional criterion for diagnosis of myelodysplastic syndromes (MDS). Aberrant antigen expression on bone marrow (BM) blasts may identify "low-grade MDS." This study aimed to examine differences in antigen expression on CD34+ BM cells between patients with MDS and those with secondary cytopenia. BM aspirates of 175 patients with cytopenia were classified as MDS or secondary cytopenia. Expression of stem cell antigens (CD34, CD133), myeloid antigens (CD13, CD33), B-cell antigens (CD19, CD10), growth factor receptors (CD117, CD123), and chemokine receptor (CD184) was examined. Thirty-two normal adults and 49 patients with CD34+ acute myeloid leukemia (AML) were also examined. High percentage of CD34+ cells, CD117 and CD123 overexpression, and abnormal CD45 expression on these cells are the best markers for MDS. These phenotypic aberrancies correlate with number of blasts and degree of dysplasia, and were similar to those in CD34+ AML, thus reflecting the relationship between these disorders.

In young children, persistent wheezing is associated with bronchial bacterial infection: a retrospective analysis.

BACKGROUND: Young children with persistent wheezing pose a diagnostic and therapeutical challenge to the pediatrician.We aimed to evaluate bacterial bronchial infection as a possible reason for non response to conventional asthma therapy, and to identify and characterise the predominant pathogens involved. METHODS: We retrospectively analysed microbiological and cytological findings in a selected population of young wheezers with symptoms unresponsive to inhaled corticosteroid (ICS) therapy, who underwent flexible bronchoscopy with bronchoalveolar lavage (BAL). Procedural measures were taken to limit contamination risk and quantitative bacterial culture of BAL fluid (significance cut-off ≥ 104 colony-forming units/ml) was used. Modern microbiological methods were used for detection of a wide panel of pathogens and for characterisation of the bacterial isolates. RESULTS: 33 children aged between 4 and 38 months, without structural anomalies of the conductive airways were evaluated. Significant bacterial BAL cultures were found in 48,5 % of patients. Haemophilus influenzae was isolated in 30,3 %, Streptococcus pneumoniae in 12,1 % and Moraxella catarrhalis in 12,1 %. All H. influenzae isolates were non-encapsulated strains and definitely distinguished from non-haemolytic H. haemolyticus. Respiratory viruses were detected in 21,9 % of cases with mixed bacterial-viral infection in 12,1 %. Cytology revealed a marked neutrophilic inflammation. CONCLUSIONS: Bacterial infection of the bronchial tree is common in persistent preschool wheezers and provides a possible explanation for non response to ICS therapy. Non-typeable H. influenzae seems to be the predominant pathogen involved, followed by S. pneumoniae and M. catarrhalis.

Cellular aging and senescence characteristics of human T-lymphocytes.

CD28-, CD57+ and KLRG1+ are cell surface markers that have been used to describe senescent T-lymphocytes in humans. However, the relationship among these phenotypes during aging, and their relationship with the concept of in vitro cellular aging have not been well established. Using five-colour flow cytometry, we analyzed peripheral blood T-lymphocytes for their expression of CD28, CD57 and KLRG1 in 11 young (Y) and 11 old (O) apparently healthy human subjects. The proportions of CD28- and CD57+ cells were significantly higher among the T-cell populations of O compared to Y subjects; the proportion of KLRG1+ cells was significantly higher only among CD8+ cells. Populations that were more frequent in the elderly participants were characterised as CD28+ CD57+, CD28- CD57+ or CD28- CD57-. The expression of p16 and p21, considered as markers for in vitro senescence, was higher in CD28+ CD57+ cells than in other subpopulations in both age groups. The expression of p21 was age-related, which was not the case for p16. Thus, although both p16 and p21 are involved in T-cell senescence, they appear to behave differently. CMV infection and shifts in subpopulations are unlikely as explanations of the observed differences. Their higher levels of p16 and p21 expression, coupled with their higher prevalence in the elderly participants make CD28+ CD57+ cells the subpopulation of T-cells most closely corresponding to the concept of senescent cells.

HLA-G expression in human embryonic stem cells and preimplantation embryos.

Human leukocyte Ag-G, a tolerogenic molecule that acts on cells of both innate and adaptive immunity, plays an important role in tumor progression, transplantation, placentation, as well as the protection of the allogeneic fetus from the maternal immune system. We investigated HLA-G mRNA and protein expression in human embryonic stem cells (hESC) derived from the inner cell mass (ICM) of blastocysts. hESC self-renew indefinitely in culture while maintaining pluripotency, providing an unlimited source of cells for therapy. HLA-G mRNA was present in early and late passage hESC, as assessed by real time RT-PCR. Protein expression was demonstrated by flow cytometry, immunocytochemistry, and ELISA on an hESC extract. Binding of HLA-G with its ILT2 receptor demonstrated the functional active status. To verify this finding in a physiologically relevant setting, HLA-G protein expression was investigated during preimplantation development. We demonstrated HLA-G protein expression in oocytes, cleavage stage embryos, and blastocysts, where we find it in trophectoderms but also in ICM cells. During blastocyst development, a downregulation of HLA-G in the ICM cells was present. This data might be important for cell therapy and transplantation because undifferentiated hESC can contaminate the transplant of differentiated stem cells and develop into malignant cancer cells.

Use of likelihood ratios improves interpretation of laboratory testing for pulmonary sarcoidosis.

Laboratory tests for pulmonary sarcoidosis (percentage lymphocytes and CD4/CD8 ratio in bronchoalveolar lavage fluid and serum angiotensin-converting enzyme activity) lack sensitivity and specificity. In a retrospective study of 153 subjects under suspicion of pulmonary sarcoidosis (36 cases and 117 patients with other diseases [control patients]), we defined likelihood ratios (LRs) for rationally selected result intervals of these tests, which improve clinical interpretation as compared with dichotomous interpretation based on a single cutoff value. By using logistic regression analysis, we further integrated the 3 individual tests into a unified algorithm that could rule out diagnosis in 57 (48.7%) of the 177 control subjects and confirm diagnosis in 12 (33%) of the 36 pulmonary sarcoidosis cases. We conclude that use of LRs improves interpretation of laboratory tests for pulmonary sarcoidosis. In addition, we present a prediction algorithm based on the combination of laboratory tests that helps clinicians confirm or exclude diagnosis in almost half of the study population.

Use of the Cell-Dyn Sapphire hematology analyzer for automated counting of blood cells in body fluids.

The enumeration and identification of blood cells in body fluids offers important information for the diagnosis and treatment of various medical conditions. Manual microscopic methods (hemacytometer total cell count and cytocentrifuged differential count) have inherent analytic and economic disadvantages but are still considered the "gold standard" methods. We evaluated the analytic and clinical performance of the Cell-Dyn Sapphire hematology analyzer (Abbott Diagnostics Division, Santa Clara, CA) for automated blood cell counting and leukocyte differential counting in cerebrospinal fluid, serous fluid (peritoneal and pleural fluid), and continuous ambulatory peritoneal dialysis fluid, and we compared the performance with the respective manual methods. In the present article, we describe its applicability for the distinct body fluids, and we highlight limitations and caveats.

Differences in baseline lymphocyte counts and autoreactivity are associated with differences in outcome of islet cell transplantation in type 1 diabetic patients.

OBJECTIVE: The metabolic outcome of islet cell transplants in type 1 diabetic patients is variable. This retrospective analysis examines whether differences in recipient characteristics at the time of transplantation are correlated with inadequate graft function. RESEARCH DESIGN AND METHODS: Thirty nonuremic C-peptide-negative type 1 diabetic patients had received an intraportal islet cell graft of comparable size under an ATG-tacrolimus-mycophenolate mofetil regimen. Baseline patient characteristics were compared with outcome parameters during the first 6 posttransplant months (i.e., plasma C-peptide, glycemic variability, and gain of insulin independence). Correlations in univariate analysis were further examined in a multivariate model. RESULTS: Patients that did not become insulin independent exhibited significantly higher counts of B-cells as well as a T-cell autoreactivity against insulinoma-associated protein 2 (IA2) and/or GAD. In one of them, a liver biopsy during posttransplant year 2 showed B-cell accumulations near insulin-positive beta-cell aggregates. Higher baseline total lymphocytes and T-cell autoreactivity were also correlated with lower plasma C-peptide levels and higher glycemic variability. CONCLUSIONS: Higher total and B-cell counts and presence of T-cell autoreactivity at baseline are independently associated with lower graft function in type 1 diabetic patients receiving intraportal islet cells under ATG-tacrolimus-mycophenolate mofetil therapy. Prospective studies are needed to assess whether control of these characteristics can help increase the function of islet cell grafts during the first year posttransplantation.

Markers of inflammation in patients with symptomatic and asymptomatic carotid artery stenosis: a case-control study.

OBJECTIVES: There is evidence that inflammation plays a role in the pathogenesis of atherosclerosis. We compared levels of inflammatory markers between patients undergoing carotid endarterectomy (CEA) and controls, and between patients with symptomatic and asymptomatic internal carotid artery (ICA) stenosis. MATERIALS AND METHODS: A total of 180 patients with ICA stenosis were compared with 180 age-matched and sex-matched controls. The biomarkers evaluated were high-sensitivity C-reactive protein (hs-CRP), soluble intercellular adhesion molecule 1, soluble vascular cell adhesion molecule 1 (sVCAM-1), and interleukin-6 (IL-6). RESULTS: The levels of hs-CRP, sVCAM-1, and IL-6 in the CEA group were significantly higher than in the control group (1.87 mg/mL vs 1.44 mg/mL, P = .011; 1408 ng/dL vs 672 ng/dL, P < .001; 11.9 pg/mL vs 6.3 pg/mL, P < .001). Multivariate linear regression analysis, adjusted for all clinical and physiologic parameters, showed a significant association between ICA stenosis and hs-CRP, sVCAM-1, and IL-6 concentrations. Analysis of symptomatic (n = 101) and asymptomatic (n = 79) ICA stenosis did not detect a difference in levels of these markers. CONCLUSIONS: Our study suggests that inflammatory markers could serve as markers for ICA atherosclerosis but are not useful to identify carotid plaque at risk for symptomatic conversion.

Migration of culture-expanded human mesenchymal stem cells through bone marrow endothelium is regulated by matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-3.

BACKGROUND AND OBJECTIVES: Mesenchymal stem cells (MSC) are adult stem cells that can be expanded many fold in vitro and have the therapeutic potential to restore the bone marrow microenvironment and support hematopoietic recovery after myeloablative conditioning for hematopoietic stem cell transplantation. Successful homing to the target tissue, such as bone marrow, implies that MSC are able to extravasate after systemic administration. However, the extravasation capacity of MSC and the underlying mechanisms are poorly understood to date. We studied in vitro the capacity of MSC to migrate through bone marrow endothelium. DESIGN AND METHODS: In vitro invasion and transendothelial migration assays were performed. The expression of matrix metalloproteinase (MMP) was analyzed by reverse transcriptase polymerase chain reaction (RT-PCR) and zymography. Migration of cells cultured at high or low confluence was compared and differential gene expression in these conditions was analyzed with microarray and real-time RT-PCR. The functional involvement in MSC migration was assessed using neutralizing anti-MMP-2 antibody, MMP-2 short interfering RNA or recombinant tissue inhibitor of metalloproteinase (TIMP-3). RESULTS: We demonstrated that MSC can invade reconstituted basement membrane and that bone marrow endothelial cells stimulate this process. We also showed that the transendothelial migration of MSC is at least partially regulated by MMP-2. High culture confluence was found to increase production of the natural MMP-inhibitor TIMP-3 and decrease transendothelial migration of MSC. INTERPRETATION AND CONCLUSIONS: We show that MSC have the potential to migrate through bone marrow endothelium and that this process involves MMP-2. Moreover, the migration of MSC is significantly influenced by the level of culture confluence. Increased culture confluence impairs migration and is related to an upregulation of TIMP-3. The therapeutic use of MSC would benefit from a selection of culture conditions that allow optimal extravasation of these cells.

Diagnostic accuracy of the FIDIS multiplex fluorescent microsphere immunodetection system for anti-extractable nuclear antigen (ENA) antibodies in connective tissue diseases.

BACKGROUND: Anti-extractable nuclear antigen antibodies (ENA) are markers of connective tissue diseases (CTDs). METHODS: We compared FIDIS reagents in the multiplex fluorescent microsphere immunodetection system to INNO-LIA and immunodiffusion for 174 antinuclear antibody-positive patients, 102 with well-defined CTDs and 72 disease controls. RESULTS: No significant differences were found in sensitivity or specificity between FIDIS and immunodiffusion, or between FIDIS and INNO-LIA for all anti-ENA in all CTD patients; nor were any differences found for individual anti-ENAs within distinct CTDs. The FIDIS sensitivity was 41% (anti-SSA) and 17% (anti-SSB) in lupus erythematosus (LE) or primary Sjögren's syndrome; 5% (anti-ribosome and anti-Sm) in LE; 17% (anti-RNP) in LE or mixed CTD; 21% (anti-Scl70) in systemic sclerosis; and 61% (anti-centromere) in limited systemic sclerosis. The specificity reached 88%-100%. Receiver operating characteristic curve areas did not differ between FIDIS and INNO-LIA. Agreement ranged from 91% (anti-SSB) to 99% (anti-Jo1) between FIDIS and INNO-LIA, and from 95% (anti-Scl70) to 100% (anti-Sm) between FIDIS and immunodiffusion. Samples scored positive with all techniques in 83% (anti-centromere), 70% (anti-RNP), 67% (anti-Jo1), 60% (anti-SSA), 40% (anti-SSB), 33% (anti-ribosome), 25% (anti-Sm) and 13% (anti-Scl70) of cases. CONCLUSIONS: The diagnostic performance of FIDIS anti-ENA reagents is comparable to immunodiffusion and INNO-LIA.