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We studied humoral and cellular immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 152 long-term care facility staff and 124 residents over a prospective 4-month period shortly after the first wave of infection in England. We show that residents of long-term care facilities developed high and stable levels of antibodies against spike protein and receptor-binding domain. Nucleocapsid-specific responses were also elevated but waned over time. Antibodies showed stable and equivalent levels of functional inhibition against spike-angiotensin-converting enzyme 2 binding in all age groups with comparable activity against viral variants of concern. SARS-CoV-2 seropositive donors showed high levels of antibodies to other beta-coronaviruses but serostatus did not impact humoral immunity to influenza or other respiratory syncytial viruses. SARS-CoV-2-specific cellular responses were similar across all ages but virus-specific populations showed elevated levels of activation in older donors. Thus, survivors of SARS-CoV-2 infection show a robust and stable immunity against the virus that does not negatively impact responses to other seasonal viruses.

Age is the strongest determinant of COVID-19 mortality, and over 2 billion people have received primary series vaccination with BNT162b2 (mRNA) or ChAdOx1 (adenoviral vector). However, the profile of sustained vaccine immunogenicity in older people is unknown. Here, we determine spike-specific humoral and cellular immunity to 8 months following BNT162b2 or ChAdOx1 in 245 people aged 80-98 years. Vaccines are strongly immunogenic, with antibodies retained in every donor, while titers fall to 23%-26% from peak. Peak immunity develops rapidly with standard interval BNT162b2, although antibody titers are enhanced 3.7-fold with extended interval. Neutralization of ancestral variants is superior following BNT162b2, while neutralization of Omicron is broadly negative. Conversely, cellular responses are stronger following ChAdOx1 and are retained to 33%-60% of peak with all vaccines. BNT162b2 and ChAdOx1 elicit strong, but differential, sustained immunogenicity in older people. These data provide a baseline to assess optimal booster regimen in this vulnerable age group.

Redox homeostasis is an integral part of many cellular processes, and its perturbation is associated with conditions such as diabetes, aging, and neurodegenerative disorders. Redox homeostasis or redox potential in organelles is maintained within a particular range to facilitate the organelle specific cellular redox reactions. Previous studies using yeast, cell systems, and nematodes have demonstrated that the Endoplasmic Reticulum (ER) has a more oxidizing environment while the cytosol exhibits a reducing redox potential. However, we know very little about how universal this phenomenon is. We created transgenic zebrafish (Danio rerio) lines with roGFP sensors targeted to the ER and cytosol for studying physiological redox potential at the systems level. In the process, we also characterized the ER-targeting signal sequence in D. rerio for the first time. Measurements of the redox state in live embryos found that the endoplasmic reticulum exhibits deviations from its expected oxidizing redox state in different regions of the developing embryos. The ER is far more reducing than expected in certain tissues of the embryo. Cytosol also exhibited unexpected redox states in some parts of the embryo. Notably, the brain showed regions with unexpected redox states in both the ER and the cytosol. Tissue-specific differences in ER-redox potential became even more evident in a transgenic line expressing the more sensitive roGFPiE variant. Thus, live monitoring of redox potential across the developing zebrafish embryos revealed unanticipated redox states of the ER that will require new biological definitions.

Allogeneic stem cell transplantation is used widely in the treatment of hematopoietic malignancy. However relapse of malignant disease is the primary cause of treatment failure and reflects loss of immunological graft versus leukaemia effect. We studied the transcriptional and phenotypic profile of CD8+ T cells in the first month following transplantation and related this to risk of subsequent relapse. Single-cell transcriptional profiling identified 5 discrete CD8+ T cell clusters. High levels of T cell activation and acquisition of a regulatory transcriptome were apparent in patients who went on to suffer disease relapse. A relapse-associated gene signature of 47 genes was then assessed in a confirmation cohort of 34 patients. High expression of the inhibitory receptor CD94/NKG2A on CD8+ T cells within the first month was associated with 4.8 fold increased risk of relapse and 2.7 fold reduction in survival over the subsequent 4 years. Furthermore, reduced expression of the activatory molecule CD96 was associated with 2.2 fold increased risk of relapse and 1.9 fold reduction in survival. This work identifies CD94 and CD96 as potential targets for CD8-directed immunotherapy in the very early phase following allogeneic transplantation with the potential to reduce long term relapse rates and improve patient survival.

Long term care facilities (LTCF) provide residential and/or nursing care support for frail and elderly people and many have suffered from a high prevalence of SARS-CoV-2 infection. Although mortality rates have been high in LTCF residents there is little information regarding the features of SARS-CoV-2-specific immunity after infection in this setting or how this may influence immunity to other infections. We studied humoral and cellular immunity against SARS-CoV-2 in 152 LTCF staff and 124 residents over a prospective 4-month period shortly after the first wave of infection and related viral serostatus to heterologous immunity to other respiratory viruses and systemic inflammatory markers. LTCF residents developed high levels of antibodies against spike protein and RBD domain which were stable over 4 months of follow up. Nucleocapsid-specific responses were also elevated in elderly donors but showed waning across all populations. Antibodies showed stable and equivalent levels of functional inhibition against spike-ACE2 binding in all age groups with comparable activity against viral variants of concern. SARS-CoV-2 seropositive donors showed high levels of antibodies to other beta-coronaviruses but serostatus did not impact humoral immunity to influenza or RSV. SARS-CoV-2-specific cellular responses were equivalent across the life course but virus-specific populations showed elevated levels of activation in older donors. LTCF residents who are survivors of SARS-CoV-2 infection thus show robust and stable immunity which does not impact responses to other seasonal viruses. These findings augur well for relative protection of LTCF residents to re-infection. Furthermore, they underlie the potent influence of previous infection on the immune response to Covid-19 vaccine which may prove to be an important determinant of future vaccine strategy.One sentence summeryCare home residents show waning of nucleocapsid specific antibodies and enhanced expression of activation markers on SARS-CoV-2 specific cells

The immune response to SARS-CoV-2 is critical in both controlling primary infection and preventing re-infection. However, there is concern that immune responses following natural infection may not be sustained and that this may predispose to recurrent infection. We analysed the magnitude and phenotype of the SARS-CoV-2 cellular immune response in 100 donors at six months following primary infection and related this to the profile of antibody level against spike, nucleoprotein and RBD over the previous six months. T-cell immune responses to SARS-CoV-2 were present by ELISPOT or ICS analysis in all donors and are characterised by predominant CD4+ T cell responses with strong IL-2 cytokine expression. Median T-cell responses were 50% higher in donors who had experienced an initial symptomatic infection indicating that the severity of primary infection establishes a ‘setpoint’ for cellular immunity that lasts for at least 6 months. The T-cell responses to both spike and nucleoprotein/membrane proteins were strongly correlated with the peak antibody level against each protein. The rate of decline in antibody level varied between individuals and higher levels of nucleoprotein-specific T cells were associated with preservation of NP-specific antibody level although no such correlation was observed in relation to spike-specific responses. In conclusion, our data are reassuring that functional SARS-CoV-2-specific T-cell responses are retained at six months following infection although the magnitude of this response is related to the clinical features of primary infection.

SARS-CoV-2 infection is generally mild or asymptomatic in children but a biological basis for this outcome is unclear. Here we compare antibody and cellular immunity in children (aged 3–11 years) and adults. Antibody responses against spike protein were high in children and seroconversion boosted responses against seasonal Beta-coronaviruses through cross-recognition of the S2 domain. Neutralization of viral variants was comparable between children and adults. Spike-specific T cell responses were more than twice as high in children and were also detected in many seronegative children, indicating pre-existing cross-reactive responses to seasonal coronaviruses. Importantly, children retained antibody and cellular responses 6 months after infection, whereas relative waning occurred in adults. Spike-specific responses were also broadly stable beyond 12 months. Therefore, children generate robust, cross-reactive and sustained immune responses to SARS-CoV-2 with focused specificity for the spike protein. These findings provide insight into the relative clinical protection that occurs in most children and might help to guide the design of pediatric vaccination regimens.

SARS-CoV-2 infection is generally mild or asymptomatic in children but the biological basis for this is unclear. We studied the profile of antibody and cellular immunity in children aged 3-11 years in comparison with adults. Antibody responses against spike and receptor binding domain (RBD) were high in children and seroconversion boosted antibody responses against seasonal Beta-coronaviruses through cross-recognition of the S2 domain. Seroneutralisation assays against alpha, beta and delta SARS-CoV-2 variants demonstrated comparable neutralising activity between children and adults. T cell responses against spike were >2-fold higher in children compared to adults and displayed a TH1 cytokine profile. SARS-CoV-2 spike-specific T cells were also detected in many seronegative children, revealing pre-existing responses that were cross-reactive with seasonal Alpha and Beta-coronaviruses. Importantly, all children retained high antibody titres and cellular responses at 6 months after infection whilst relative antibody waning was seen in adults. Spike-specific responses in children also remained broadly stable beyond 12 months. Children thus distinctly generate robust, cross-reactive and sustained immune responses after SARS-CoV-2 infection with focussed specificity against spike protein. These observations demonstrate novel features of SARS-CoV-2-specific immune responses in children and may provide insight into their relative clinical protection. Furthermore, this information will help to guide the introduction of vaccination regimens in the paediatric population.

Summary Chemotherapy pre-conditioning is an essential component of chimeric antigen receptor transduced cell therapy. Acute lymphopenia-induced proliferation (LIP) is known to be driven primarily by homeostatic cytokines, but little is known on the underlying mechanisms in humans. We undertook phenotypic and transcriptional analysis of T cells undergoing LIP two weeks post-myeloablative autograft stem cell transplantation. Strong IL-7 signaling was reflected in downregulated IL-7R expression on all T cells, including naive cells, along with parallel increased IL-2Rα expression. Notably, activated residual naive cells expressed Fas indicating recent TCR engagement. Moreover, proportion of Ki67 + FoxP3+ Tregs was almost doubled. Transcriptional analysis revealed increased fatty acid metabolism and interferon signaling responses. In contrast, TGF-β signaling was strongly suppressed. Thus, human LIP response is characterized by cytokine and TCR-driven proliferation which drives global T cell activation but also preferentially triggers regulatory cell expansion which may limit tumor-specific immunity. These features indicate potential therapeutic opportunities to manipulate immunotherapy regimens incorporating LIP conditioning protocols., Graphical abstract, Highlights • Lymphopenia drives global T cell activation with selective FoxP3+ T cell proliferation • naive T cells undergo TCR-mediated activation and effector populations expand • IL-7R is downregulated on all T cell subsets whilst IL-2Rα expression increases • Fatty acid metabolism & interferon-signaling increase; TGF-β responses suppressed, Immunology; Cell Biology

PD-1 is expressed on exhausted T cells in cancer patients but its physiological role remains uncertain. We determined the phenotype, function and transcriptional correlates of PD-1 expression on cytomegalovirus-specific CD4+ T cells during latent infection. PD-1 expression ranged from 10–85% and remained stable over time within individual donors. This ‘setpoint’ was correlated with viral load at primary infection. PD-1+ CD4+ T cells display strong cytotoxic function but generate low levels of Th1 cytokines which is only partially reversed by PD-1 blockade. TCR clonotypes showed variable sharing between PD-1+ and PD-1- CMV-specific cells indicating that PD-1 status is defined either during T cell priming or subsequent clonal expansion. Physiological PD-1+ CD4+ T cells therefore display a unique ‘high cytotoxicity-low cytokine’ phenotype and may act to suppress viral reactivation whilst minimizing tissue inflammation. Improved understanding of the physiological role of PD-1 will help to delineate the mechanisms, and potential reversal, of PD-1+ CD4+ T cell exhaustion in patients with malignant disease., Author summary PD-1 is expressed by a subset of CMV-specific CD4 T cells, we show expression is not associated with activation or ‘exhaustion’. We go onto show the size of the PD-1+ pool is established at primary infection, and expression remains stable on antigen specific cell populations and on individual cells, indicating expression is imprinted and controlled by a ‘set point’. PD-1 expressing CD4 T cells comprise cells with strong cytotoxicity but reduced cytokine production which may act to suppress viral reactivation whilst minimizing tissue inflammation.

Fatigueness of the driver is considered a major cause that account to a large numbers of death worldwide. Thus it becomes necessary to develop a system that can help reduce such accidents. During drowsy state, significant differences in the facial features of the driver are observed in comparison to the normal state. The system proposed in the paper is focused on detection as well as alarming the driver after recording the physiological state of the driver. We made use of the non-intrusive approach which monitors the subject in real-time, wherein the blinking of eyes as well as the mouth shape (yawn) of the operator are observed, and if the operator's eyes are shut for more than the threshold value, or the operator is yawning, or if both of them are detected at the same instance then the driver's state is concluded for precautions. The proposed system is designed using Python Language, and OpenCV application is used for image processing employing the use of Viola - Jones Algorithm for the detection of facial features.

The immune response to SARS-CoV-2 is critical in both controlling primary infection and preventing re-infection. However, there is concern that immune responses following natural infection may not be sustained and that this may predispose to recurrent infection. We analysed the magnitude and phenotype of the SARS-CoV-2 cellular immune response in 100 donors at six months following primary infection and related this to the profile of antibody level against spike, nucleoprotein and RBD over the previous six months. T-cell immune responses to SARS-CoV-2 were present by ELISPOT and/or ICS analysis in all donors and are characterised by predominant CD4+ T cell responses with strong IL-2 cytokine expression. Median T-cell responses were 50% higher in donors who had experienced an initial symptomatic infection indicating that the severity of primary infection establishes a ‘setpoint’ for cellular immunity that lasts for at least 6 months. The T-cell responses to both spike and nucleoprotein/membrane proteins were strongly correlated with the peak antibody level against each protein. The rate of decline in antibody level varied between individuals and higher levels of nucleoprotein-specific T cells were associated with preservation of NP-specific antibody level although no such correlation was observed in relation to spike-specific responses. In conclusion, our data are reassuring that functional SARS-CoV-2-specific T-cell responses are retained at six months following infection although the magnitude of this response is related to the clinical features of primary infection.

Summary Primary stimulation of T cells is believed to trigger unidirectional differentiation from naive to effector and memory subsets. Here we demonstrate that IL-7 can drive the phenotypic reversion of recently differentiated human central and effector memory CD8+ T cells into a naive-like phenotype. These “naive-revertant” cells display a phenotype similar to that of previously reported stem cell memory populations and undergo rapid differentiation and functional response following secondary challenge. The chromatin landscape of reverted cells undergoes substantial epigenetic reorganization with increased accessibility for cytokine-induced mediators such as STAT and closure of BATF-dependent sites that drive terminal differentiation. Phenotypic reversion may at least partly explain the generation of “stem cell memory” CD8+ T cells and reveals cells within the phenotypically naive CD8+ T cell pool that are epigenetically primed for secondary stimulation. This information provides insight into mechanisms that support maintenance of T cell memory and may guide therapeutic manipulation of T cell differentiation., Graphical Abstract, Highlights • γ-chain cytokines revert newly differentiated CD8+ T cells to a naive-like phenotype • These “naive-revertant” are primed for secondary challenge • Their chromatin landscape is reminiscent of memory cells • Specific signaling pathways and transcription factors are involved, Biological Sciences; Molecular Biology; Immunology

CD117 (cKit) is the receptor for stem cell factor (SCF) and plays an important role in early haemopoiesis. We show that CD117 is also expressed following priming of mature human CD8+ T cells in vitro and is detectable following primary infection in vivo. CD117 expression is mediated through an intrinsic pathway and is suppressed by IL-12. Importantly, the extent of CD117 expression is inversely related to the strength of the activating stimulus and subsequent engagement with cell-bound SCF markedly increases susceptibility to apoptosis. CD117 is therefore likely to shape the pattern of CD8+ T cell immunodominance during a primary immune response by rendering cells with low avidity for antigen more prone to apoptosis. Furthermore, CD117+ T cells are highly sensitive to apoptosis mediated by galectin-1, a molecule commonly expressed within the tumor microenvironment, and CD117 expression may therefore represent a novel and potentially targetable mechanism of tumor immune evasion.

End-stage differentiation of antigen-specific T-cells may precede loss of immune responses against e.g. viral infections after allogeneic stem cell transplantation (SCT). Antigen-specific CD8+ T-cells detected by HLA/peptide multimers largely comprise CD45RA-/CCR7- effector memory (TEM) and CD45RA+/CCR7- TEMRA subsets. A majority of terminally differentiated T-cells is considered to be part of the heterogeneous TEMRA subset. The senescence marker CD57 has been functionally described in memory T-cells mainly composed of central memory (TCM) and TEM cells. However, its role specifically in TEMRA cells remained undefined. Here, we investigated the relevance of CD57 to separate human CD8+ TEMRA cells into functionally distinct subsets. CD57- CD8+ TEMRA cells isolated from healthy donors had considerably longer telomeres and showed significantly more BrdU uptake and IFN-γ release upon stimulation compared to the CD57+ counterpart. Cytomegalovirus (CMV) specific T-cells isolated from patients after allogeneic SCT were purified into CD57+ and CD57- TEMRA subsets. CMV specific CD57- TEMRA cells had longer telomeres and a considerably higher CMV peptide sensitivity in BrdU uptake and IFN-γ release assays compared to CD57+ TEMRA cells. In contrast, CD57+ and CD57- TEMRA cells showed comparable peptide specific cytotoxicity. Finally, CD57- CD8+ TEMRA cells partially changed phenotypically into TEM cells and gained CD57 expression, while CD57+ CD8+ TEMRA cells hardly changed phenotypically and showed considerable cell death after in vitro stimulation. To the best of our knowledge, these data show for the first time that CD57 separates CD8+ TEMRA cells into a terminally differentiated CD57+ population and a so far functionally undescribed “young” CD57- TEMRA subset with high proliferative capacity and differentiation plasticity.

CMV reactivation is a major complication after allogeneic stem cell transplantation (SCT). Immune reconstitution of CMV-specific CTLs (CMV-CTLs) is essential for virus control. During CMV-CTL monitoring using mutated HLA/CMV tetramers selectively detecting high-avidity T cells, we observed coappearance of CMV-CTLs with low (CMV tetlow CTLs) and high tetramer binding (CMV tethigh CTLs) in 53/115 CMV IgG+ patients stem cell transplanted from CMV IgG+ donors. However, the relevance of these coappearing differentially tetramer binding (“dual”) CMV-CTLs was unclear. In this study, we investigated the kinetics, properties, and clinical impact of coappearing CMV tetlow and tethigh CTLs after allogeneic SCT. Patients with dual CMV-CTLs had more CMV tethigh than tetlow CTLs. Chimerism analysis of isolated CMV tetlow and tethigh CTLs revealed their exclusive donor origin. CMV tetlow and tethigh CTLs had an identical effector memory CD45RA−CCR7− and CD45RA+CCR7− T cell distribution, equal differentiation, senescence, and exhaustion marker expression and were negative for regulatory CD8+ T cell markers. Isolated CMV tetlow and tethigh CTLs were equally sensitive to CMV peptides in IFN-γ release and cytotoxicity assays. However, CMV tethigh CTLs proliferated more in response to low CMV peptide concentrations than tetlow CTLs. TCR repertoire analysis revealed that CMV tetlow and tethigh CTLs use different TCRs. Finally, dual CMV-CTLs were not associated with CMV antigenemia. In conclusion, these data show for the first time, to our knowledge, that both CMV tetlow and tethigh CTLs are functional effector T cells differing by proliferation, numbers in peripheral blood, and probably by their precursors without increasing the CMV reactivation risk after allogeneic SCT.

ObjectivesCisplatin-induced nephrotoxicity is the main cause for its dose-limited use in the treatment of various cancers and results in acute renal cell injury through generation of reactive oxygen species. Chrysin possess antioxidant, anti-inflammatory and anti-cancer properties. The aim of this study was to investigate the protective efficacy of chrysin against cisplatin-induced nephrotoxicity.MethodsThirty male Wistar rats were divided into five groups with six rats in each group. Group I served as control and received corn oil (vehicle of chrysin) for 14 days and 0.9% saline (vehicle of cisplatin) on day 14 only. Group II received a single intraperitoneal injection of cisplatin on day 14. Group III and IV were pretreated with two different doses of chrysin in addition to cisplatin and group V received chrysin only. Rats were examined for the effect of chrysin on cisplatin induced depletion of antioxidant enzymes, induction of lipid peroxidation and DNA damage in the kidney, utilizing a well-established model of cisplatin-induced nephropathy.Key findingsPretreatment with chrysin significantly attenuated cisplatin-induced renal oxidative damage by diminishing the DNA damage and toxicity markers, such as creatinine and blood urea nitrogen, lipid peroxidation and xanthine oxidase activity, accompanied by increase in enzymatic (catalase, glutathione peroxidase, glutathione reductase and glutathione-S-transferase) and non-enzymatic (reduced glutathione) antioxidant status. Histological findings further substantiated the protective efficacy of chrysin, which reduced cisplatin-induced renal damage.ConclusionsThe data of the present study suggest that chrysin effectively suppress cisplatin-induced renal injury by ameliorating oxidative stress.

Allogeneic stem cell transplantation can cure some patients with hematopoietic malignancy but relies on development of a donor T cell alloreactive immune response which develops very early but is difficult to study due to intense lymphopenia. We characterised the phenotype and functional profile of T cells at day 14 in patients undergoing transplantation. T cells were present at very low number but displayed intense proliferation with strong cytokine production. Oligoclonal expansions at day 14 came to represent a substantial fraction of the established T cell pool and were recruited into tissues affected by graft-versus-host disease. Transcriptional analysis uncovered a range of potential targets for immune manipulation including OX40L, TWEAK and CD70. These findings reveal that recognition of alloantigen rapidly drives naïve T cells towards a unique phenotype characterised by intense functional activation. Moreover they demonstrate that early clonal T cell responses are recruited to sites of subsequent tissue damage and provide a range of novel targets for potential therapeutic immunomodulation.

Alloreactive CD8+ T-cells mediate the curative graft-versus-leukaemia effect, the anti-viral immunity and graft-versus-host-disease (GvHD) after allogeneic stem cell transplantation (SCT). Thus, immune reconstitution with CD8+ T-cells is critical for the outcome of patients after allogeneic SCT. Certain miRNAs such as miR-146a or miR-155 play an important role in the regulation of post-transplant immunity in mice. While some miRNAs e.g. miR-423 or miR-155 are regulated in plasma or full blood during acute GvHD also in man, the relevance and expression profile of miRNAs in T-cells after allogeneic SCT is unknown. miR-625-3p has recently been described to be overexpressed in colorectal malignancies where it promotes migration, invasion and apoptosis resistance. Since similar regulative functions in cancer and T-cells have been described for an increasing number of miRNAs, we assumed a role for the cancer-related miR-625-3p also in T-cells. Here, we studied miR-625-3p expression selectively in CD8+ T-cells both in vitro and during immune reconstitution after allogeneic SCT in man. T-cell receptor stimulation lead to miR-625-3p upregulation in human CD8+ T-cells in vitro. Maintenance of elevated miR-625-3p expression levels was dependent on ongoing T-cell proliferation and was abrogated by withdrawal of interleukin 2 or the mTOR inhibitor rapamycin. Finally, miR-625-3p expression was analyzed in human CD8+ T-cells purified from 137 peripheral blood samples longitudinally collected from 74 patients after allogeneic SCT. miR-625-3p expression was upregulated on day 25 and on day 45, i.e. during the early phase of CD8+ T-cell reconstitution after allogeneic SCT and subsequently declined with completion of CD8+ T-cell reconstitution until day 150. In conclusion, this study has shown for the first time that miR-625-3p is regulated in CD8+ T-cells during proliferation in vitro and during early immune reconstitution after allogeneic SCT in vivo. These results warrant further studies to identify the targets and function of miR-625-3p in CD8+ T-cells and to analyze its predictive value for an effective immune reconstitution.

Cancer is a disease of uncontrolled cell growth in tissues. This growth may lead to metastasis, which is the invasion of adjacent tissue and infiltration beyond the site of initiation. Cancer is initiated by activation of oncogenes or inactivation of tumor suppressor genes. Nearly 10-30% of all adenocarcinomas are due to the mutations in the K-ras protooncogene. [1] Function and regulation of Bcl-2 proteins depends upon their interaction with other non-family member proteins, including NIP1, NIP2, NIP3, p53 BP2, Raf-1, CED-4, calcineurin, R-Ras and Bag-1 to form homo and hetero dimmers.[21] Bag1 belongs to the Bcl2 associated athanogene (BAG) family of multifunctional proteins. This widely expressed protein interacts with a number of signalling molecules (including Bcl2, HGF receptor and Raf1) as it regulates signalling molecules in pathways involving cell survival, growth and differentiation. [13] Bcl2 associated athanogene (BAG1) protein is involved in regulation of the Ras/Raf signal transduction pathway. Of particular relevance to tumour cells, BAG-1 interacts with the anti-apoptotic BCL-2 protein, various nuclear hormone receptors the 70 kDa heat shock proteins, Hsc70 and Hsp70; and serine/threonine kinase. Raf-1 which plays an important role in MAPK pathway.[2][3][4] Recent studies have shown that BAG-1 expression is frequently altered in malignant cells, and BAG-1 expression may have clinical value as a prognostic or predictive marker for various cancer types including breast cancer, prostate cancer and lung cancer.[6][7][8] (Fig 1) Interaction with chaperones may account for many of the pleiotropic effects associated with BAG-1 over expression. The finding that BAG-1 can independently associate with Raf-1 or Bcl-2 provides at least two mechanisms by which BAG-1 promotes cell survival. [20] Bcl2-associated athanogene (BAG) family proteins participate in a wide variety of cellular processes to regulate growth control pathways, including cell survival (stress response), proliferation, migration, signalling and apoptosis (Fig 2).[2][5][18] This family of cochaperones functionally regulates signal transduction proteins Raf/MEK/ERK and transcription factors important for cell stress responses, apoptosis, proliferation, cell migration and hormone action. In response to stress, they bind to heat shock proteins HSP70/HSC70 coordinating cell growth signals, by down-regulating the activity of serine/threonine kinase, Raf-1, which plays an important role in MAPK pathway. [5][9] The proteins show anti-apoptotic activity and increase the anti-cell death function of BCL-2 induced by various stimuli. Over expression of BAG-1 suppresses activation of caspases and

This paper proposes an RGB-based, secure technique to maintain and authenticate the integrity of a document. The novel Steganographic algorithm that we have proposed has its strength greatly enhanced by use of hybrid cryptography on data that is to be hidden in cover image. The secret message is converted into two kinds of plaintexts by subsequent ASCII and binary conversions and suitable bit stuffing. Two cipher texts are obtained using RSA and IDEA algorithms, which make up for a hybrid crypto-system. Both of these cipher texts are hidden in the cover image of the note using our novel, variable-length lSB-based Steganographic technique for data hiding in RGB images. One cipher text is used to determine the position for data hiding and the other cipher text is hidden in the lSBs of the color channel (that have minimum color contribution in the image) of the chosen pixels using variable length lSB based data embedding. Maximum intensity color channel is used to indicate which minimum intensity channel has how many bits of data embedded in it. We define the indicator and data channels from among the RGB color channels and use them for hiding of respective data in the cover image. Choosing such channels for hiding indicator and data bits, causes minimum distortion in the color of the pixels and such changes go undetected by Human Vision System (HVS).

Fourteen patients with myeloid leukemia (12 with acute and 2 with chronic myelogenous leukemia) were transplanted from their HLA-identical (n = 9) or haploidentical (n = 5) family donors with CD34-enriched stem cells (HSCT) without further immunosuppression. In order to induce a graft versus leukemia (GvL) effect and to investigate the possibility of controlling graft-versus-host disease (GvHD), the standard transplantation protocol was adapted to include transfusion of gene-modified donor T-cells after HSCT in 11 patients, 3 did not receive any T-cells. Donor-T-cells were transduced with the replication-deficient retrovirus SFCMM-3 which expresses the herpes simplex thymidine kinase (HSV-Tk) as a suicide gene and the truncated low affinity nerve growth factor receptor (ΔLNGFR) for selection purposes. After transfusion, SFCMM-3 transduced T-cells were detectable in all 11 patients by PCR and FACS analyses immediately after transfusion and during the follow up period (range: 1.1-11 years). Two of 9 patients developed acute GvHD: one of the skin, grade 1, 56 days after transfusion of the transduced cells, the other grade II which was successfully treated with ganciclovir. Loss of bcr-abl gene expression was achieved in one patient after expansion of transduced cells. Donor chimerism was stabilized after transfusion of transduced cells in all patients treated. In one patient a cytomegalovirus-reactivation was treated by the transfusion of gene-modified donor T-cells also indicating effectiveness of treatment. To date, 5 patients have relapsed, and died, one after a second HSCT. Two of the patients without transduced T-cells died due to relapse and 7 patients are alive and well and in complete clinical remission. Thus we have shown that transfusion of transduced T-cells is effective and safe in a long follow-up of 11 years post transfusion. Disclosures: No relevant conflicts of interest to declare.