Association among Terminally Differentiated T Cells, Frailty, and Dependency in a Group of Cuban Centenarians.

INTRODUCTION: Centenarians are considered a model of successful aging. Cuba exhibits one of the oldest populations in Latin America with more than two thousand centenarians. METHODS: This study aimed to evaluate the immune phenotype of forty-three Cuban centenarians, their clinical characteristics such as comorbidities, frailty, body mass index, and some hemochemical parameters. RESULTS: Centenarians had normal body mass indexes, relatively good health status, and 21.95% of them had no comorbidities; 53.6% were classified as frail, and 7% were classified as robust. In addition, 17% of centenarians were independent, and 41.46% were moderately dependent. The seroprevalence against cytomegalovirus was 100%. Concerning pro-inflammatory markers, the majority of them had very low cytokine levels and serum C-reactive protein around the normal limit. We also found the predominance of memory subsets over naive compartments in CD4+ and CD8+ T cells. Terminally differentiated CD8+CD28- T cells were higher in frail centenarians than in pre-frail, while CD8+CD57+ and CD8+EMRA T cells were higher in moderately and severely dependent individuals than in independent individuals. Severely dependent centenarians had a lower CD4+/CD8+ ratio. CONCLUSION: This study describes for the first time the predominance of memory subsets over naive compartments in CD4+ and CD8+ T cells, as well as its relation to frailty and/or dependency in a group of Cuban centenarians. Further studies are needed to continue understanding the natural biological aging mechanism and the relationship between terminally differentiated lymphocytes and inflammaging in the context of extreme longevity.

Associations among cytokines, EGF and lymphocyte subpopulations in patients diagnosed with advanced lung cancer.

Aging is considered the single most significant risk factor for the majority of common malignances including lung cancer. Together immunosenescence, changes occurring with aging in the immune system, and inflammaging, characterizes by a chronic, subclinical accumulation of pro-inflammatory factors, are suggested to stand at the origin of most of the diseases of the elderly, such as cancer. The aim of this study was to determine associations among lymphocyte subpopulations, pro-inflammatory cytokines and epidermal growth factor (EGF) in patients diagnosed with non-small cell lung cancer (NSCLC). Forty-six advanced NSCLC patients were enrolled. Sixteen patients with newly diagnosed and before treatment and 30 patients after first-line platinum-based chemotherapy. Peripheral blood subpopulations were studied by flow cytometry and serum concentrations of soluble factors by ELISA. The frequency of naïve CD4+ T cells, naïve B cells and central memory CD8+ T cells were significantly lower in NSCLC patients after chemotherapy, while effector memory CD4+ T cells and terminally differentiated CD8+ T cells were significantly higher. IL-1ß and TNFα significantly correlated among them before and after platinum-based chemotherapy. Terminally differentiated T cells expressing CD57+ significantly correlated with TNFα and IL-1ß. For the first time, associations between EGF serum levels and terminally differentiated CD4+ T cells, and memory B cells were detected. This study confirms the association among terminally differentiated lymphocytes and pro-inflammatory cytokines in patients diagnosed with lung cancer, reinforcing the interconnection between terminally differentiated lymphocytes and pro-inflammatory cytokines. Clinical trial registration number: RPCEC00000205, http://registroclinico.sld.cu/.

Biomarkers related to immunosenescence: relationships with therapy and survival in lung cancer patients.

PURPOSE: There are well-known alterations occurring within the immune system with aging. Collectively, these changes are known as immunosenescence. The incidence of malignancies also increases with age. The aim of this study was to determine the presence of immunosenescence biomarkers in non-small cell lung cancer (NSCLC) patients and to evaluate some of them as predictive biomarkers of CIMAvax-EGF cancer vaccine efficacy. METHODS: Sixty-six NSCLC patients, vaccinated or not with CIMAvax-EGF cancer vaccine, and 37 age-matched controls were enrolled. Peripheral blood samples were studied for CD19+, CD4+, CD8+, CD28-, CD57+ and CD45RA+ subpopulations by flow cytometry. RESULTS: Absolute count of CD19+ and the CD4/CD8 ratio were significantly lower in NSCLC patients than in age-paired controls, while highly differentiated T cells increased in NSCLC patients treated with platinum-based chemotherapy. Using Cox regression, we were able to dichotomize the patient population according to biomarkers. Vaccinated patients with frequency <24 % of CD8 + CD28- T cells, >40 % of CD4 T cells and CD4/CD8 ratio higher than two at the beginning of immunotherapy achieved a 20-month increase in median survival regarding control patients. CONCLUSIONS: Distribution of lymphocyte subsets was influenced by cancer and chemotherapy in NSCLC patients. CD19 + B cells decrease by cancer disease and not by chemotherapy, and CD28- subpopulations increase by chemotherapy and not by cancer. The proportion of CD8 + CD28- T cells, CD4+ T cells and CD4/CD8 ratio can be used as predictive biomarkers of CIMAvax-EGF efficacy in NSCLC patients and thereby could, be a useful tool for a personalized treatment.

Thymic Polypeptide Fraction Biomodulina T Decreases Exhausted and Terminally Differentiated EMRA T Cells in Advanced Lung Cancer Patients Treated With Platinum-Based Chemotherapy.

Lung cancer is the second cause of cancer related deaths worldwide. Chemotherapy and immunotherapy represent the current standard of care for advanced NSCLC. Platinum-based chemotherapy expands late-differentiated T cell populations. Therefore, immune restoration after chemotherapy to adjuvate the immunotherapeutic potential could be crucial. The aim of this study was to evaluate the effect of Biomodulina T (BT), a thymic polypeptide fraction, on peripheral lymphocytes subpopulations in the context of cancer disease. Additionally, whether these effects might induce a better response to CIMAvax-EGF, an epidermal growth factor (EGF) depleting immunotherapy. Eighteen advanced NSCLC patients were evaluated after being treated with platinum-based chemotherapy. We found that the frequency of terminally differentiated effector T cells re-expressing CD45RA (EMRA) CD4+ (p=0.0031) and CD8+ (p=0.0372) T cells decreased with the administration of BT, whereas CD4+ naive T cells increase in more than 70% of the patients. Remarkably, CD4+ and CD8+ T lymphocytes expressing programmed cell death receptor-1 (PD1) significantly decreased after BT administration (p=0.0005 and p<0.0001, respectively). We also found an enhancement of the anti-EGF antibody response with a large percentage of patients treated with CIMAvax-EGF reaching the good antibody response condition after four vaccine doses. Moreover, the median overall survival of patients treated with CIMAvax-EGF was 16.09 months. In conclusion, our results suggest that the immunorestoration generated by the administration of BT after first-line chemotherapy may induce a better immune response to CIMAvax-EGF that could translate into the clinical benefit of patients diagnosed with advanced NSCLC.

Anti-EGF antibodies as surrogate biomarkers of clinical efficacy in stage IIIB/IV non-small-cell lung cancer patients treated with an optimized CIMAvax-EGF vaccination schedule.

We previously reported that CIMAvax-EGF vaccine is safe, immunogenic and efficacious to treat advanced non-small-cell lung cancer (NSCLC) patients. A phase III trial was designed using an optimized immunization schedule. It included higher antigen dose and injections at multiple sites. Immune response and circulating biomarkers were studied in a subset of patients. EGF-specific antibody titers, IgG subclasses, peptide immunodominance and circulating biomarkers were assessed by ELISA. In vitro EGF-neutralization capacity of immune sera and EGF-IgG binding kinetics was evaluated by Western Blot and Surface Plasmon Resonance (SPR) technology, respectively. We show that CIMAvax-EGF elicited mainly IgG3/IgG4 antibodies at titers exceeding 1:4000 in 80% of vaccinated patients after 3 months of treatment. The EGF-specific humoral response was directed against the central region of the EGF molecule. For the first time, the kinetic constants of EGF-specific antibodies were measured evidencing affinity maturation of antibody repertoire up to month 12 of vaccination. Notably, the capacity of post-immune sera to inhibit EGFR phosphorylation significantly increased during the course of the immunization scheme and was related to clinical outcome (P = .013, log-rank test). Basal concentrations of EGF and TGFα in the serum were affected by EGF-based immunization. In conclusion, the CIMAvax-EGF vaccine induces an EGF-specific protective humoral response in a high percent of NSCLC vaccinated patients, the quantity and quality of which were associated with clinical benefit (clinical trial registration number: RPCEC00000161, http://registroclinico.sld.cu/). Abbreviations: EGF: epidermal growth factor; EGFR: epidermal growth factor receptor; Ab: antibody; AR: amphiregulin; NSCLC: non-small-cell lung cancer; rhEGF: recombinant human epidermal growth factor; BSC: best supportive care; TGFα: tumor growth factor alpha; IL-8: interleukin 8; MAb: monoclonal antibody; SPR: surface plasmon resonance.

Biomodulina T partially restores immunosenescent CD4 and CD8 T cell compartments in the elderly.

The changes that occur in the immune system with aging are commonly termed immunosenescence. Immunosenescence affects almost all components and functions of the immune response. The most commonly described change is a decrease in numbers and proportions of naïve T cells combined with the increase of terminally differentiated T lymphocytes, mainly affecting CD8+ T cells. The changes in the naïve T cell compartment are principally attributed to thymic involution and lifelong chronic antigen stimulation, among other triggers. Several strategies such as hormonal products, thymic peptides, or cytokines have been proposed for the restoration of the immune system. Here we show the effects of Biomodulina T (BT) on several populations of the immune system when administered to elderly patients diagnosed with recurrent respiratory infections. BT is a polypeptide fraction of bovine thymus, a Cuban product that obtained sanitary registration in 1994 for its immunomodulatory effects. We found that CD4+ naïve T, CD8+ stem cell-like memory (SCM) T, CD4+ recent thymic emigrants (RTE) T and CD4+ CD31+ naïve T cells increased with the administration of BT, whereas CD4+ and CD8+ T cells expressing PD1 decreased after the treatment with BT. Additionally, the proliferative capacity of CD4+ T cells measured by Ki67 expression, and the CD4+ T cell ability to produce IFN-γ were also improved by BT. Moreover, BT did not increase CD4+ Tregs. Altogether, these findings suggest that BT administration is a promising strategy for immune restoration in elderly patients and improvement of immunotherapeutic potential in cancer patients.

Nimotuzumab Induces NK Cell Activation, Cytotoxicity, Dendritic Cell Maturation and Expansion of EGFR-Specific T Cells in Head and Neck Cancer Patients.

Survival benefit and long-term duration of clinical response have been seen using the epidermal growth factor receptor (EGFR)-targeted monoclonal antibody (mAb) nimotuzumab. Blocking EGFR signaling may not be the only mechanism of action underlying its efficacy. As an IgG1 isotype mAb, nimotuzumab's capacity of killing tumor cells by antibody dependent cellular cytotoxicity (ADCC) and to induce an immune response in cancer patients have not been studied. ADCC-induced by nimotuzumab was determined using a 51Cr release assay. The in vitro effect of nimotuzumab on natural killer (NK) cell activation and dendritic cell (DC) maturation and the in vivo frequency of circulating regulatory T cells (Tregs) and NK cells were assessed by flow cytometry. Cytokine levels in supernatants were determined by ELISA. ELISpot was carried out to quantify EGFR-specific T cells in nimotuzumab-treated head and neck cancer (HNSCC) patients. Nimotuzumab was able to kill EGFR+ tumor cells by NK cell-mediated ADCC. Nimotuzumab-activated NK cells promoted DC maturation and EGFR-specific CD8+ T cell priming. Interestingly, nimotuzumab led to upregulation of some immune checkpoint molecules on NK cells (TIM-3) and DC (PD-L1), to a lower extent than another EGFR mAb, cetuximab. Furthermore, circulating EGFR-specific T cells were identified in nimotuzumab-treated HNSCC patients. Notably, nimotuzumab combined with cisplatin-based chemotherapy and radiation increased the frequency of peripheral CD4+CD39+FOXP3+Tregs which otherwise were decreased to baseline values when nimotuzumab was used as monotherapy. The frequency of circulating NK cells remained constant during treatment. Nimotuzumab-induced, NK cell-mediated DC priming led to induction of anti-EGFR specific T cells in HNSCC patients. The association between EGFR-specific T cells and patient clinical benefit with nimotuzumab treatment should be investigated.