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Avacta Halts Sale Of Covid-19 Rapid Antigen LFT - 0 views

www.pharmacy.biz/t-to-boost-omicron-sensitivity

Avacta pharmacy-business Do-lateral-flow-tests-detect-omicron rapid-antigen-LFT-AffiDX Rapid-antigen-test Can-lateral-flow-tests-detect-omicron

shared by pharmacybiz on 11 Jan 22 - No Cached
  • pharmacybiz on 11 Jan 22
     
    Britain's biotech firm Avacta Group on Monday (January 10) announced halting sales of its Covid-19 rapid antigen lateral flow test AffiDX to replace antibodies in the device and increase its ability to diagnose the Omicron variant. The company stated that AffiDX is capable of detecting Omicron when the virus is present in high numbers in samples, but the sensitivity of the test reduces at lower viral loads. The performance of all rapid antigen tests came under scanner in wake of a large number of mutations in the Omicron variant. AffiDX contains both a proprietary Affimer reagent and a commercially available antibody. The Affimer reagent detects the Omicron variant with the same sensitivity as the Delta variant, and performance of the antibody is paired with the Affimer reagent in the test. This has been affected by the additional Omicron mutations, the firm said. Alastair Smith, chief executive of Avacta Group, said: "Our determination to only provide high quality, high performance diagnostic tests has led us to the correct decision to pause all marketing of the AffiDX® lateral flow antigen test. We have, of course, been unable to market the product in the UK since October 2021, as the product continues to await approval under the new CTDA regulatory process.
Nathan Goodyear

Hyperthermia as an immunotherapy strategy for cancer - 1 views

www.ncbi.nlm.nih.gov/...PMC2828267

cancer hyperthermia

shared by Nathan Goodyear on 29 Nov 18 - No Cached
  • the notion of treating human cancers with heat dates back to the writings of Hippocrates
  • enhance the efficiency of standard cancer therapies, such as chemotherapy and radiation treatment
  • After antigen uptake at tumor sites, APCs have the ability to create a robust response by entering lymphoid compartments and programming lymphocytes
  • ...36 more annotations...
  • Hyperthermia differs fundamentally from fever in that it elevates the core body temperature without changing the physiological set point
  • hyperthermia is induced by increasing the heat load and/or inactivating heat dissipation
  • mor cells [2]. Although significant cell killing could be achieved by heating cells or tissues to temperatures > 42°C for 1 or more hours, the application, measurement and consistency of this temperature range within the setting of cancer clinical trials
  • mild temperature hyperthermia (ie, within the fever-range, 39–41°C)
    • Nathan Goodyear
      Nathan Goodyear on 04 Aug 19
       
      101.2 to 105.8
  • moderate hyperthermia (41°C)
    • Nathan Goodyear
      Nathan Goodyear on 04 Aug 19
       
      105.8 F
  • Hsps are a family of stress-induced proteins
  • they are key regulators of cellular protein activity, turnover and trafficking
  • Hsps ensure appropriate post-translational protein folding, and are able to refold denatured proteins, or mark irreversibly damaged proteins for destruction
  • the ability of fever-range hyperthermia to induce reactive immunity against tumor antigens through DCs and NK-cells is likely mediated by Hsps
  • thermotolerance
  • Hsps support the malignant phenotype of cancer cells by not only affecting the cells’ survival, but also participating in angiogenesis, invasion, metastasis and immortalization mechanisms
  • Hsps released from stressed or dying cells activate dendritic cells (DCs), transforming them into mature APCs
  • In theory, fever-range hyperthermia may take advantage of tumor cell Hsps by inducing their release from tumor cells and augmenting DC priming against tumor antigens
  • In several models of hyperthermia, heat-treated tumors exhibited improved DC priming and generation of systemic immunity to tumor cell
  • hyperthermia alone can enhance antigen display by tumor cells, thus rendering them even more susceptible to programmed immune clearance
  • Fever-range hyperthermia may also induce Hsps
  • Hsps may exert an adjuvant effect by bolstering MHC class II and co-stimulatory molecule expression by DCs
  • thermal ablation of liver tumors in particular has demonstrated an ability to potentiate immune responses [57, 58] and elicit robust T-cell infiltrates at ablation sites
  • specific Hsp, Hsp70, directly inhibits apoptosis pathways in cancer cells, as demonstrated in human pancreatic, prostate and gastric cancer cells
  • Cross-priming is the ability of extracellular Hsps complexed to tumor peptides to be internalized and presented in the context of MHC class I molecules on APCs, thus allowing potent priming of CTLs against tumor antigens
  • It has been reported that Hsps are generated from necrotic tumor cell lysates, but not from tumor cells undergoing apoptosis
  • tumor cells exposed to hyperthermia in the heat shock range (42°C for 4h) prior to lysing, DC activation and cross-priming were significantly enhanced with the application of heat
  • Due to the ability of Hsps to activate DCs directly by chaperoning tumor antigens upon their release [28], it is possible that both local and regional immune stimulation can be achieved with hyperthermia.
  • support the use of hyperthermia as an inducer of Hsps to serve as ‘danger signals’, activating antitumor immune responses
  • whole-body hyperthermia not only augments immune responses, but also stimulates the migration of skin-derived DCs to draining lymph nodes
    • Nathan Goodyear
      Nathan Goodyear on 04 Aug 19
       
      This allows for the activation of lymphocytes by the activated dendritic cells.
  • suggest a valuable role of hyperthermia in DC cancer vaccine strategies
  • In mice treated with fever-range whole-body hyperthermia, tumor growth was significantly inhibited and NK-cell infiltration increased
    • Nathan Goodyear
      Nathan Goodyear on 04 Aug 19
       
      Hyperthermia increased NK cell activation, proliferation, and infiltration, which equals increased cytotoxicity.
  • exposure to fever-range hyperthermia resulted in improved endogenous NK-cell cytotoxicity to several cancer types
  • improved activation and function of DCs and NK cells following hyperthermia
  • Hyperthermia increases the expression ICAM-1 a key adhesion molecule,
  • The combined effects of hyperthermia on lymphoid tissue endothelium and lymphocytes can promote immune surveillance and increase the probability of naive lymphocytes leaving the circulation and encountering their cognate antigen displayed by DCs in lymphoid organs.
  • In independent clinical studies, whole-body hyperthermia resulted in a transient decrease in circulating lymphocytes in patients with advanced cancer [12, 94, 99, 100], a finding which mirrored observations in animal models in which lymphocyte entry into lymph noeds was increased following hyperthermia treatment [93]. Enhanced recruitment of lymphocytes to lymphoid tissues may be exploited in the treatment of malignancies.
  • The initial tumor antigen presentation and initiation of clonal expansion of CTLs transpires in the lymph nodes and cannot take place outside this specialized compartment
  • the ability of DCs present in the lymph nodes to stimulate an anti-tumor immune response is critical
  • hyperthermia has been shown to improve immune surveillance by T-cell
  • and to increase DC trafficking to lymph nodes
  • Nathan Goodyear on 29 Nov 18
     
    Great review of hyperthermia.
Nathan Goodyear

Activation of NK cells by extracellular heat shock protein 70 through induction of NKG2... - 0 views

www.ncbi.nlm.nih.gov/...PMC2935777

heat shock proteins NK cells natural killer cells cancer

shared by Nathan Goodyear on 29 Sep 18 - No Cached
  • Heat shock proteins (HSPs) are intracellular molecular chaperones that play essential roles in facilitating protein folding
  • their ability to interact with APCs and to chaperone antigenic peptides for cross-presentation to MHC class I and class II molecules on APC
  • vaccination with HSP70 was associated with increased T cell, as well as NK cell, activity in patients with CML
  • ...6 more annotations...
  • HSP70 did not activate NK cells directly. Instead, HSP70 induced the expression of an NKG2D ligand MICA on DCs, which then activated NK cells in an NKG2D-dependent manner.
  • DCs are the most powerful professional antigen presenting cells (APCs) that are instrumental in processing antigens and orchestrating antigen-specific adaptive immunity and tolerance
  • NK cells and DCs can functionally interact with each other both in vitro and in vivo
  • autologous HSP70 could stimulate significant IFN-γ production
  • The magnitude of the IFN-γ response was different from patient to patient and correlated with the number of functional NK cells
  • In addition, 10 out of 14 patients had significantly increased IFN-γ producing cells in the peripheral blood after HSP70 vaccinations, which is again in line with increased NK cell activity as reported in our original study in these patients
  • Nathan Goodyear on 29 Sep 18
     
    great review of the relationship between heat shock proteins and NK cells.
Nathan Goodyear

http://partnecglobal.eurasiansupply.com/ds/rd/rdgf/_pdf7.pdf - 0 views

partnecglobal.eurasiansupply.com/..._pdf7.pdf

maitake mushrooms cancer beta-glucan Grifola frondosa NK APC antigen presenting cells ICAM-1

shared by Nathan Goodyear on 21 May 14 - No Cached
  • Nathan Goodyear on 21 May 14
     
    Study finds that maitake mushroom extract, MD-Fraction (a beta-glucan), has significant anti-tumor activity and anti-metastasis activity through NK activity, Antigen presenting cells, and through suppression of ICAM-1.
Nathan Goodyear

Immune responses to malignancies - 0 views

www.ncbi.nlm.nih.gov/...PMC3721350

cancer immune system

shared by Nathan Goodyear on 18 Apr 18 - No Cached
  • increased densities of T-cell infiltrates with a high proportion of CD8+ T cells within primary colorectal carcinomas were associated with a significant protection against tumor recurrence
  • coexpression of genes mediating cytotoxicity and TH1 adaptive immune responses accurately predicted survival in patients with colorectal carcinoma independently of the metastatic status.
  • tumor-specific cytolytic T lymphocytes (CTLs)
  • ...10 more annotations...
  • tumor-associated antigens (TAs)
  • Proinflammatory cytokines secreted by inflammatory cells can contribute to tumor progression, and soluble factors produced by the tumor in response to nonspecific or tumor-specific signals, such as prostaglandin E2 (PGE2), adenosine, or TGF-β, downregulate functions of immune cells
  • they are largely ineffective in arresting tumor growth, although they can proliferate and mediate antitumor cytotoxicity on their removal from the tumor bed and ex vivo IL-2 activation.42
  • DCs (HLA-DR+CD86+CD80+CD14−) are nature’s best APCs
  • They are a common component of tumor immune infiltrates and are responsible for the uptake, processing, and cross-presentation of TAs to naive or memory T cells, thus playing a crucial role in the generation of tumor-specific effector T cells
  • DCs control the induction of Treg cells. In patients with cancer, cellular interactions between antigen-presenting DCs and T cells lead to expansion and accumulation of Treg cells at the tumor site and in the periphery
  • NK cells (CD3−CD56+CD16+), which mediate innate immunity and contain both perforin-rich and granzyme-rich granules, are well equipped to mediate lysis of tumor cells
  • B cells (CD19+, CD20+) are also rare in most human tumors, with the exception of breast cancer and melanoma
  • The initial acute inflammation involving the recruitment and influx of antitumor effector cells is replaced by chronic inflammation in later stages of tumor progression
  • Tissue hypoxia plays a major role in shaping the nature of immune infiltrates in tumors
  • Nathan Goodyear on 18 Apr 18
     
    Another great review of the immune system during different stages of carcinogenesis; how the cancer manipulates the immue system to cloak itself from the immune system.
Nathan Goodyear

Improved leukemia-free survival after postconsolidation immunotherapy with histamine di... - 0 views

www.bloodjournal.org/...88

AML acute myeloid leukemia leukemia IL-2 histamine

shared by Nathan Goodyear on 12 May 18 - No Cached
  • several independent lines of evidence suggest that cytotoxic effector cells such as T cells and natural killer (NK) cells participate in protecting patients with AML against relapse
  • A plethora of mechanisms have been proposed to account for the dysfunctional antileukemic lymphocytes in AML, including the production of T-cell- and NK-cell-inhibitory factors by AML blasts,48 a deficient expression of NK-cell receptors on leukemic cells,49 inhibition of antileukemic lymphocytes by mononuclear phagocytes,4 and an impaired stimulatory interaction between the CD28 antigen expressed by T cells and contact antigens on AML blasts
  • This trial met the primary endpoint and thus showed a significantly improved LFS for patients receiving HDC/IL-2 as compared with the current standard of care
  • ...2 more annotations...
  • T cells and NK cells with antileukemic activity can be recovered from most patients with AML in remission not receiving a transplant,
  • The present study evaluated an approach to immunotherapy in AML in which IL-2 is supplemented with histamine dihydrochloride (HDC) to enhance the function of cytotoxic antileukemic lymphocytes
  • Nathan Goodyear on 12 May 18
     
    IL-2 plus histamine in patients with AML complete remission improves leukemia free survival.
Nathan Goodyear

Natural Killer Cells in Pregnancy and Recurrent Pregnancy Loss: Endocrine and Immunolog... - 0 views

edrv.endojournals.org/...44.full

natural killer cells pregnancy loss recurrent immune system miscarriage NK

shared by Nathan Goodyear on 15 Apr 12 - No Cached
  • NK cells have been the cells most extensively studied, primarily because they constitute the predominant leukocyte population present in the endometrium at the time of implantation and in early pregnancy
  • parental chromosomal abnormalities, uterine anatomic anomalies, endometrial infections, endocrine etiologies (luteal phase defect, thyroid dysfunction, uncontrolled diabetes mellitus), antiphospholipid syndrome, inherited thrombophilias, and alloimmune causes
  • estrogen
  • ...28 more annotations...
  • progesterone
  • prolactin
  • In summary, in vivo animal experiments have shown an inhibitory role of estrogen on peripheral NK cell lytic activity, which is partly due to suppression of NK cell output by the bone marrow and partly due to suppression of individual NK cell cytotoxicity. However, in vitro studies so far have failed to show conclusively a direct effect of estrogen on NK cells.
  • At the progesterone concentrations believed to be present in the uterus [up to 10−5 m at the maternal-fetal interface (35)], studies consistently show inhibition of lymphocyte proliferation (33) and inhibition of NK cytolytic activity in vitro
  • The exact role of prolactin in NK cell regulation is unknown.
  • The overall effects of estrogen on NK cells are likely multifactorial, therefore, and depend on the type of cell affected as well as the kind of ER expressed by that cell.
  • It is known that progesterone can directly affect T cell differentiation in vitro, suppressing development of the Th1 pathway and enhancing differentiation along the Th2 pathway (44)
  • Th1 cells predominantly produce interferon-γ (IFN-γ), IL-2, and TNF-β and are involved in cell-mediated immunity. Th2 cells produce IL-4, IL-5, IL-6, IL-10, and IL-13 and stimulate humoral immunity
  • Furthermore, in response to progesterone, γδ T cells produce progesterone-induced blocking factor (PIBF) (54
  • A defining characteristic of NK cells is their ability to lyse target cells without prior sensitization and without restriction by HLA antigens.
  • NK cell function is mainly regulated by IL-2 and IFN-γ
  • IL-2 causes both NK cell proliferation and enhanced cytotoxicity. IFN-γ augments NK cytolytic activity, but does not cause NK proliferation. The two cytokines act synergistically to augment NK cytotoxicity (6).
  • The largest leukocyte population in the endometrium consists of NK cells named large granulated lymphocytes
  • there is a significant increase in the number of uNK cells throughout the secretory phase, which peaks in early pregnancy when uNK cells comprise about 75% of uterine leukocytes (62)
  • Second, uNK cell phenotype changes during the normal menstrual cycle and early pregnancy (68)
  • general proinflammatory effect of estrogen, causing an influx of macrophages and neutrophils, which is antagonized by progesterone through its receptor (70, 71).
  • The mechanism of such a progesterone-induced local immunosuppression is unclear.
  • progesterone plays an important role in proliferation and differentiation of uNK cells (32).
  • Through promotion of a uterine Th2 environment, progesterone could indirectly affect uNK cell function
  • The mechanism of this increase in uNK cell numbers has been addressed in both human and mouse models, and is likely the result of: 1) recruitment of peripheral NK cells to the uterus, and 2) proliferation of existing uNK cells
  • prolactin system plays an important role in implantation and the maintenance of pregnancy
  • the exact pathways of hormonal regulation of NK cells remain to be delineated.
  • The exact function of uNK cells has not yet been unequivocally determined
  • uNK cells express a different cytokine profile, compared with resting peripheral NK cells. mRNAs for granulocyte CSF, M-CSF, GM-CSF, TNF-α, IFN-γ, TGF-β, and leukemia inhibitory factor (LIF) have been found in decidual CD56+ cells
  • Their increased numbers in early pregnancy, their hormonal dependence, and their close proximity to the infiltrating trophoblast all suggest that they play an important role in the regulation of the maternal immune response to the fetal allograft and the control of trophoblast growth and invasion during human pregnancy
  • role of uNK cell-derived cytokines on trophoblast growth and differentiation (114, 115, 116, 117).
  • Th1 immunity to trophoblast is associated with RPL, whereas Th2 immunity is associated with a successful pregnancy
  • RPL is associated with Th1 immunity, for which NK cells are partly responsible.
  • Nathan Goodyear on 15 Apr 12
     
    dysregulated immune system plays role in recurrent miscarriage.  Specifically, this article discusses natural killer cells (NK).
Nathan Goodyear

Glutathione Redox Regulates Airway Hyperresponsiveness and Airway Inflammation in Mice ... - 0 views

www.atsjournals.org/...rcmb.2006-0423OC

glutathione asthma inflammation

shared by Nathan Goodyear on 07 Jul 16 - No Cached
  • γ-GCE reduced levels of IL-4, IL-5, IL-10, and the chemokines eotaxin and RANTES (regulated on activation, normal T cell expressed and secreted) in bronchoalveolar lavage fluid, whereas it enhanced the production of IL-12 and IFN-γ.
  • γ-GCE suppressed eosinophils infiltration
  • γ-GCE directly inhibited chemokine-induced eosinophil chemotaxis
  • ...10 more annotations...
  • these findings suggest that changing glutathione redox balance, increase in GSH level, and the GSH/GSSG ratio by γ-GCE, ameliorate bronchial asthma by altering the Th1/Th2 imbalance through IL-12 production from APC and suppressing chemokine production and eosinophil migration itself.
  • Bronchial asthma is a typical helper T cell type 2 (Th2) disease
  • Through the release of Th2 cytokines, such as IL-4, IL-5, and IL-13, orchestrate the recruitment and activation of the primary effector cells of the allergic response: the mast cells and the eosinophils
  • Glutathione is the most abundant nonprotein sulfhydryl compound in almost all cells. This tripeptide plays a significant role in many biological processes. It also constitutes the first line of the cellular defense mechanism against oxidative injury along with SOD, ascorbate, vitamin E, and catalase, and is the major intracellular redox buffer in ubiquitous cell types
  • We have shown that glutathione redox status, namely the balance between intracellular reduced (GSH) and oxidized (GSSG) glutathione, in murine antigen-presenting cells (APC) plays a central role in determining which of the reductive and oxidative APC predominate during immune status, and the balance between reductive and oxidative APC regulates Th1/Th2 balance through production of IL-12
  • we have also shown that exposure of human alveolar macrophages to the Th1 cytokine IFN-γ or the Th2 cytokine IL-4 either increases or decreases the GSH/GSSG ratio, respectively, which regulates Th1/Th2 balance through IL-12 production
  • the ability to generate a Th1 or Th2 type response has turned out to depend not only on T cells but also on the intracellular glutathione redox status of APC
  • Th1 cytokine IFN-γ and Th2 cytokine IL-4 increases and decreases the GSH/GSSG ratio, respectively, and that this ratio influences LPS-induced IL-12 production from alveolar macrophages
  • the ability to generate a Th1 or Th2 response is dependent on glutathione redox status of APC
  • administration of γ-GCE elevates GSH level and GSH/GSSG ratio in the lung, and ameliorates AHR and eosinophilic airway inflammation by altering the Th1/Th2 balance and suppressing chemokine production and eosinophil migration in a mouse asthma model
  • Nathan Goodyear on 07 Jul 16
     
    glutathione redox reaction plays an important role in the ability to balance Th1 and Th2 and thus disease potential i.e. asthma as this study example.  
Nathan Goodyear

Interleukin‐2 enhances the natural killer cell response to Herceptin‐coated H... - 1 views

onlinelibrary.wiley.com/...%3AAID-IMMU3016%3E3.0.CO%3B2-J

IL-2 breast cancer cancer NK cells HER-2 immunotherapy

shared by Nathan Goodyear on 18 Jun 18 - No Cached
  • administration of low‐dose IL‐2 results in expansion of a CD3– / CD56+ NK cell population in patients with advanced cancer
  • approximately 20 % will overexpress theHer2 / neu proto‐oncogene
  • In breast cancer, Her2 / neu overexpression is associated with a worse histologicalgrade, decreased relapse‐free and overall survival periods, and altered sensitivity to chemotherapeutic regimens
  • ...17 more annotations...
  • NK cells are large granular lymphocytes that comprise approximately 10 % of circulating lymphocytes
  • all human NK cells express the CD56 antigen
  • treatment with various concentrations of IL‐2 in vivo may induce distinct functions within the NK cell compartment and, therefore, may have profound effects on NK cell‐mediated cytotoxicity
  • CD56bright
  • CD56dim
  • We show here that ADCC conducted by NK cells in vitro is enhanced by IL‐2 activation and is critically dependent on interactions between FcγRIII on NK cells and Herceptin‐coated tumor targets
  • administration of low‐dose IL‐2 to patients results in the marked expansion of a CD56+ population of immune effectors with the ability to lyse antibody‐coated cancer targets
  • NK cells represented only 7 % of lymphocytes prior to therapy but comprised over 50 % of the population after 10 weeks of low‐dose IL‐2
  • These data suggest that the enhanced ADCC seen following the expansion of NK cells with low‐dose IL‐2 is likely due to an increase in the overall number of NK cells
  • co‐administration of IL‐2 with rhu4D5 mAb will enhance activation of NK cell effector functions
  • Stimulation of NK cells with IL‐2 resulted in a significant increase in the lysis of rhu4D5‐coated targets
  • We have shown that costimulation with IL‐2 plus rhu4D5 results in significant production of IFN‐γ by NK cells with concomitant up‐regulation of cell‐surface activation and adhesion molecules
  • It has been previously demonstrated that continuous low‐dose IL‐2 can expand a CD56+ lymphocyte population, and we have now shown that this cell population is a potent mediator of ADCC against rhu4D5 mAb‐coated Her2 / neu+ targets
  • These results suggest that administration of low‐dose IL‐2 can be used to expand NK cell numbers, while higher doses may be used to enhance their cytolytic capacity in the setting of mAb therapy
  • we have demonstrated that NK cell lysis of Her2 / neu+ breast cancer cell lines in the presence of rhu4D5 mAb is markedly enhanced following stimulation with IL‐2
  • we have presented evidence that administration of low‐dose IL‐2 in vivo results in the expansion of a potent NK cell effector population
  • Our experiments suggest that NK cells costimulated with IL‐2 and immobilized IgG can secrete potent immunomodulatory cytokines which may serve to potentiate the anti‐tumor immune response.
  • Nathan Goodyear on 18 Jun 18
     
    low dose IL-2 found to expand NK levels in conjuction in with herceptin in HER-2 positive breast cancer cell lines.
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