114 research outputs found
Enhanced B-cell differentiation and reduced proliferative capacity in chronic hepatitis C and chronic hepatitis B virus infections
BACKGROUND & AIMS: Chronic microial infections aare frequently associated with B-cell activation and polyclonal proliferation, potentially leading to autoimmunity and lymphoproliferative disorders. We assessed B-cell phenotype and function in chronic hepatitis B (HBV) and chronic hepatitis C (HCV) virus infection.
METHODS: We studied 70 patients with chronic HCV infection, 34 with chronic HBV infection and 54 healthy controls, B-cell phenotype was assessed by flow cytometry using monoclonal antibodies specific for CD27, the CD69, CD71, and CD86 activation markers and the chemokine receptor CXCR3. Differentiation into immunoglobulin-producing cells (IPC) was analysed by ELISpot upon stimulation and with CD40 ligand+IL-10 as surrogate bystander T-cell help or CpG oligodeoxynucleotide+IL-2, as innate immunity signal. Proliferation was examined by cytometry using carboxyfluorescein diacetate succinimidyl ester (CFSE) after stimulation with CpG.
RESULTS: A significantly higher proportion of B cells from both HCV-and HBV-infected patients expressed activation markers compared with controls and a positive correlation was found between CXCR3(+) B cells and HCV RNA values. Memory B cells from patients with chronic HCV and HBV infections showed enhanced differentiation into IPC compared with controls, although this was restricted to IgG and at a lower level in HCV-compared with HBV-infected patients. Moreover, patients' activated B cells displayed significantly lower proliferative ability compared to healthy donors despite low expression of the FcRL4 exhaustin marker.
CONCLUSIONS: B-cell activation, but not exhaustion, is common in chronic viral hepatitis. However, enhanced B-cell differentiation and deficient proliferative capacity were not associated with commitment to terminal differentiation
Elements Related to Heterogeneity of Antibody-Dependent Cell Cytotoxicity in Patients Under Trastuzumab Therapy for Primary Operable Breast Cancer Overexpressing Her2
Preliminary results from a pilot trial on trastuzumab's mechanism of action against operable breast tumors overexpressing Her2 suggested a role for antibody-dependent cell cytotoxicity (ADCC). To examine factors affecting ADCC intensity and variability, we extended this study to the phenotypic and functional analysis of circulating mononuclear cells in 18 patients. ADCC was induced by trastuzumab therapy in 15 of 18 patients (83%). Inability to develop ADCC in three patients did not depend on inadequate levels of trastuzumab because further increase in its concentration in vitro was ineffective. Rather, susceptibility to develop ADCC was fairly predicted by test with trastuzumab before therapy and was correlated to the number of lymphocytes coexpressing CD16 and CD56. Phenotypic analysis at the end of ADCC evaluating down-regulation of CD16, and up-regulation of CD69 and CD107a, confirmed that natural killer (NK) cells and CD56+ T cells were involved in productive engagement of trastuzumab. Also, the killing efficiency of CD16+ lymphocytes was influenced by 158 V/F polymorphism of FcγRIII (CD16), whereas variations of CD247 on NK cells were consistent with trends between ADCC before and after therapy. Complete pathologic response was observed in one patient showing ADCC of outstanding intensity, whereas four cases of partial response showed intermediate ADCC; none of the three patients unable to mount ADCC had significant tumor regression. These data indicate that quantity and lytic efficiency of CD16+ lymphocytes are major factors for ADCC induction by trastuzumab, and confirm that breast cancer responses to short-term trastuzumab monotherapy may depend on involvement of the ADCC mechanism. [Cancer Res 2007;67(24):11991–9
Gender differences in internet addiction: A study on variables related to its possible development
Internet addiction and its related variables (i.e., internet gaming addiction, social media addiction, fear of missing out, phubbing) have mostly been investigated in the general population without considering possible gender differences. The present study aimed to investigate the specific characteristics of men and women in the possible development of pathological behaviors related to internet addiction. A total of 276 participants (of ages ranging from 18 to 30 years old) were recruited in the study (46.7% were males) and responded to online questionnaires on variables related to internet addiction and psychological traits. The results showed that gender represents a key factor in explaining why individuals are addicted to the internet in different ways. Stepwise linear regression analyses showed that both genders shared social media addiction as the primary predictor of internet addiction but also exclusive predictors for each gender. Knowing the variables underlying the development of internet Addiction can be useful for both prevention and treatment and tailoring intervention for this addictive behavior
Natural killer cell functional dichotomy in chronic hepatitis B and chronic hepatitis C virus infections
Background & Aims: The phenotypic and functional characteristics of natural killer (NK) cells in chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are incompletely defined and largely controversial. Methods: We studied NK cell receptor expression, cytotoxic activity, and cytokine production in peripheral blood mononuclear cells from 35 patients with chronic hepatitis C, 22 with chronic hepatitis B, and 30 healthy controls. Results: Patients with chronic HBV infection had an increased proportion of NKG2C+ NK cells with normal inhibitory receptor expression and a lower proportion of activated NK cells compared with HCV+ patients, which was associated with normal or reduced cytolytic activity and markedly dysfunctional tumor necrosis factor-\u3b1 and interferon-\u3b3 production. Patients with chronic HCV infection showed a predominantly activating phenotype, featuring a decreased percentage of cells expressing the inhibitory receptor KIR3DL1 and a concomitant increase in the proportion of NKG2D+ NK cells. Expression of the CD69 early activation antigen on NK cells positively correlated with serum alanine aminotransferase and HCV RNA values, suggesting participation of virus-induced effector NK cells in liver necroinflammation. Phenotypic changes in HCV+ patients were associated with enhanced cytokine-induced cytolytic activity and increased usage of natural cytotoxicity and NKG2D receptor pathways, accompanied by defective cytokine production, although to a lesser extent than patients with chronic HBV infection. Conclusions: These findings provide evidence for a functional dichotomy in patients with chronic HBV and HCV infections, featuring conserved or enhanced cytolytic activity and dysfunctional cytokine production, which may contribute to virus persistence
Circulating adrenomedullin estimates survival and reversibility of organ failure in sepsis: the prospective observational multinational Adrenomedullin and Outcome in Sepsis and Septic Shock-1 (AdrenOSS-1) study
Background: Adrenomedullin (ADM) regulates vascular tone and endothelial permeability during sepsis. Levels of circulating biologically active ADM (bio-ADM) show an inverse relationship with blood pressure and a direct relationship with vasopressor requirement. In the present prospective observational multinational Adrenomedullin and Outcome in Sepsis and Septic Shock 1 (, AdrenOSS-1) study, we assessed relationships between circulating bio-ADM during the initial intensive care unit (ICU) stay and short-term outcome in order to eventually design a biomarker-guided randomized controlled trial. Methods: AdrenOSS-1 was a prospective observational multinational study. The primary outcome was 28-day mortality. Secondary outcomes included organ failure as defined by Sequential Organ Failure Assessment (SOFA) score, organ support with focus on vasopressor/inotropic use, and need for renal replacement therapy. AdrenOSS-1 included 583 patients admitted to the ICU with sepsis or septic shock. Results: Circulating bio-ADM levels were measured upon admission and at day 2. Median bio-ADM concentration upon admission was 80.5 pg/ml [IQR 41.5-148.1 pg/ml]. Initial SOFA score was 7 [IQR 5-10], and 28-day mortality was 22%. We found marked associations between bio-ADM upon admission and 28-day mortality (unadjusted standardized HR 2.3 [CI 1.9-2.9]; adjusted HR 1.6 [CI 1.1-2.5]) and between bio-ADM levels and SOFA score (p < 0.0001). Need of vasopressor/inotrope, renal replacement therapy, and positive fluid balance were more prevalent in patients with a bio-ADM > 70 pg/ml upon admission than in those with bio-ADM ≤ 70 pg/ml. In patients with bio-ADM > 70 pg/ml upon admission, decrease in bio-ADM below 70 pg/ml at day 2 was associated with recovery of organ function at day 7 and better 28-day outcome (9.5% mortality). By contrast, persistently elevated bio-ADM at day 2 was associated with prolonged organ dysfunction and high 28-day mortality (38.1% mortality, HR 4.9, 95% CI 2.5-9.8). Conclusions: AdrenOSS-1 shows that early levels and rapid changes in bio-ADM estimate short-term outcome in sepsis and septic shock. These data are the backbone of the design of the biomarker-guided AdrenOSS-2 trial. Trial registration: ClinicalTrials.gov, NCT02393781. Registered on March 19, 2015
In vitro activity of pertuzumab in combination with trastuzumab in uterine serous papillary adenocarcinoma
BACKGROUND: Uterine serous papillary adenocarcinoma (USPC) is a rare but highly aggressive variant of endometrial cancer.
Pertuzumab is a new humanised monoclonal antibody (mAb) targeting the epidermal growth factor type II receptor (HER2/neu).
We evaluated pertuzumab activity separately or in combination with trastuzumab against primary USPC cell lines expressing different
levels of HER2/neu.
METHODS: Six USPC cell lines were assessed by immunohistochemistry (IHC), flow cytometry, and real-time PCR for HER2/neu
expression. c-erbB2 gene amplification was evaluated using fluorescent in situ hybridisation (FISH). Sensitivity to pertuzumab and
trastuzumab-induced antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) was
evaluated in 5 h chromium release assays. Pertuzumab cytostatic activity was evaluated using proliferation-based assays.
RESULTS: Three USPC cell lines stained heavily for HER2/neu by IHC and showed amplification of the c-erbB2 gene by FISH.
The remaining FISH-negative USPCs expressed HER2/neu at 0/1\ufe levels. In cytotoxicity experiments against USPC with a high
HER2/neu expression, pertuzumab and trastuzumab were similarly effective in inducing strong ADCC. The addition of complementcontaining
plasma and interleukin-2 increased the cytotoxic effect induced by both mAbs. In low HER2/neu USPC expressors,
trastuzumab was more potent than pertuzumab in inducing ADCC. Importantly, in this setting, the combination of pertuzumab
with trastuzumab significantly increased the ADCC effect induced by trastuzumab alone (P\ubc0.02). Finally, pertuzumab induced
a significant inhibition in the proliferation of all USPC cell lines tested, regardless of their HER-2/neu expression.
CONCLUSION: Pertuzumab and trastuzumab induce equally strong ADCC and CDC in FISH-positive USPC cell lines. Pertuzumab
significantly increases tratuzumab-induced ADCC against USPC with a low HER2/neu expression and may represent a new
therapeutic agent in patients harbouring advanced/recurrent and/or refractory USPC
Improved Natural Killer cell activity and retained anti-tumor CD8+ T cell responses contribute to the induction of a pathological complete response in HER2-positive breast cancer patients undergoing neoadjuvant chemotherapy
Natural killer cells are crucial for the efficacy of Icon (factor VII/human IgG1 Fc) immunotherapy in human tongue cancer
<p>Abstract</p> <p>Background</p> <p>Icon is a novel, dual neovascular- and cancer cell-targeting immunotherapeutic agent and has shown efficacy in the treatment of cancer, wet form macular degeneration and endometriosis. However, its underlying mechanism remains to be investigated. The objective of this study is to elucidate the mechanism of Icon immunotherapy in cancer using a squamous carcinoma human tongue cancer line TCA8113 <it>in vitro </it>and <it>in vivo </it>in severe combined immunodeficiency (SCID) mice.</p> <p>Results</p> <p>We showed that Icon, as a chimeric factor VII and human IgG1 Fc immunoconjugate, could separately induce murine natural killer (NK) cells and activate complement to kill TCA8113 cancer cells <it>in vitro </it>via antibody dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC). However, Icon-NK ADCC had a significantly stronger effect than that of Icon-CDC. Moreover, Icon could completely eradicate established human tongue tumour xenografts <it>in vivo </it>in the CB-17 strain of SCID mice that have functional NK cells at a normal level, whereas it was less effective in SCID/Beige mice that do not have functional NK cells.</p> <p>Conclusions</p> <p>We conclude that NK cells are crucial for the efficacy of Icon immunotherapy in the treatment of cancer. The results also suggest that impaired NK level/activity could contribute to the resistance to therapeutic antibodies that are currently under investigation in preclinical and clinical studies.</p
Anti-tumor activity and toxicokinetics analysis of MGAH22, an anti-HER2 monoclonal antibody with enhanced Fcγ receptor binding properties
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