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Background: Free Hamstring, Bone patellar tendon-bone, Peroneus Longus, and quadriceps tendon grafts are widely being used for Anterior cruciate ligament (ACL) reconstruction with a satisfactory outcome. Free grafts are avascular and theirs tibial side fixation insufficiency is a potential cause of failure in ACL reconstruction. Tibial attachment preserving hamstring graft preserves the vascularity and mechanical strength on the tibial side, and could be a viable option in an anterior cruciate ligament (ACL) reconstruction, The authors describe the early outcome of the surgical technique of ACL reconstruction (ACLR) with tibial attachment sparing hamstring graft without implant on the tibial side. Material and methods: The hamstring insertion preserving five stranded graft was used for ACL reconstruction with adjustable endobutton for femoral side fixation and no implant for tibial side fixation. Thirty-six patients with one-year follow-ups were included in the study. Results: The mean length of the prepared graft attached to the tibia was 95.5 ± 4 mm, and the mean width was 8.6 ± 0.7 mm and 8.2 ± 0.6 mm on the tibial and femoral side respectively. None had a failure of graft till the final follow-up. The preoperative International knee documentation committee score (IKDC) mean score improved from 47.3 ± 8.9 to 87.3 ± 6.7 at one-year follow-up. The preoperative Lysholm score (LS) improved from 58.1 ± 12.8 to 90.4 ± 4.9 at one-year follow-up. Conclusion: Attachment-sparing hamstring graft with a femoral side-only implant is a simple, cost-effective technique that provides a satisfactory outcome.

Abstract Intrinsic metabolism shapes the immune environment associated with immune suppression and tolerance in settings such as organ transplantation and cancer. However, little is known about the metabolic activities in an immunosuppressive environment. In this study, we employed metagenomic, metabolomic, and immunological approaches to profile the early effects of the immunosuppressant drug tacrolimus, antibiotics, or both in gut lumen and circulation using a murine model. Tacrolimus induced rapid and profound alterations in metabolic activities within two days of treatment, prior to alterations in gut microbiota composition and structure. The metabolic profile and gut microbiome after seven days of treatment was distinct from that after two days of treatment, indicating continuous drug effects on both gut microbial ecosystem and host metabolism. The most affected taxonomic groups are Clostriales and Verrucomicrobiae (i.e., Akkermansia muciniphila), and the most affected metabolic pathways included a group of interconnected amino acids, bile acid conjugation, glucose homeostasis, and energy production. Highly correlated metabolic changes were observed between lumen and serum metabolism, supporting their significant interactions. Despite a small sample size, this study explored the largely uncharacterized microbial and metabolic events in an immunosuppressed environment and demonstrated that early changes in metabolic activities can have significant implications that may serve as antecedent biomarkers of immune activation or quiescence. To understand the intricate relationships among gut microbiome, metabolic activities, and immune cells in an immune suppressed environment is a prerequisite for developing strategies to monitor and optimize alloimmune responses that determine transplant outcomes.

Antigen-specific tolerance represents a promising strategy to treat type 1 diabetes and islet allograft rejection. Here, the authors deliver immune signals to lymph nodes to promote antigen-specific regulatory T cells and prevent disease in models of type 1 diabetes and allogenic islet transplantation.

Abstract The beneficial effects attributed to Bifidobacterium are largely attributed to their immunomodulatory capabilities, which are likely to be species- and even strain-specific. However, their strain-specificity in direct and indirect immune modulation remain largely uncharacterized. We have shown that B. pseudolongum UMB-MBP-01, a murine isolate strain, is capable of suppressing inflammation and reducing fibrosis in vivo. To ascertain the mechanism driving this activity and to determine if it is specific to UMB-MBP-01, we compared it to a porcine tropic strain B. pseudolongum ATCC25526 using a combination of cell culture and in vivo experimentation and comparative genomics approaches. Despite many shared features, we demonstrate that these two strains possess distinct genetic repertoires in carbohydrate assimilation, differential activation signatures and cytokine responses signatures in innate immune cells, and differential effects on lymph node morphology with unique local and systemic leukocyte distribution. Importantly, the administration of each B. pseudolongum strain resulted in major divergence in the structure, composition, and function of gut microbiota. This was accompanied by markedly different changes in intestinal transcriptional activities, suggesting strain-specific modulation of the endogenous gut microbiota as a key to immune modulatory host responses. Our study demonstrated a single probiotic strain can influence local, regional, and systemic immunity through both innate and adaptive pathways in a strain-specific manner. It highlights the importance to investigate both the endogenous gut microbiome and the intestinal responses in response to probiotic supplementation, which underpins the mechanisms through which the probiotic strains drive the strain-specific effect to impact health outcomes.

Fibroblastic reticular cells (FRCs) play important roles in tolerance by producing laminin α4 (Lama4) and altering lymph node (LN) structure and function. The present study revealed the specific roles of extracellular matrix Lama4 in regulating LN conduits using FRC-specific KO mouse strains. FRC-derived Lama4 maintained conduit fiber integrity, as its depletion altered conduit morphology and structure and reduced homeostatic conduit flow. Lama4 regulated the lymphotoxin β receptor (LTβR) pathway, which is critical for conduit and LN integrity. Depleting LTβR in FRCs further reduced conduits and impaired reticular fibers. Lama4 was indispensable for FRC generation and survival, as FRCs lacking Lama4 displayed reduced proliferation but upregulated senescence and apoptosis. During acute immunization, FRC Lama4 deficiency increased antigen flow through conduits. Importantly, adoptive transfer of WT FRCs to FRC Lama4–deficient mice rescued conduit structure, ameliorated Treg and chemokine distribution, and restored transplant allograft acceptance, which were all impaired by FRC Lama4 depletion. Single-cell RNA sequencing analysis of LN stromal cells indicated that the laminin and collagen signaling pathways linked crosstalk among FRC subsets and endothelial cells. This study demonstrated that FRC Lama4 is responsible for maintaining conduits by FRCs and can be harnessed to potentiate FRC-based immunomodulation.

Influence maximization in online social networks is a trending research area due to its use in many real-world domains. Influence maximization addresses the problem of identifying a k-size subset of nodes in a social network which can trigger a cascade of further adoptions, leading to maximum influence spread across the social network. In this paper, influence maximization has been proposed by combining a node’s connections and its actual past activity pattern. Analyzing node’s activity with respect to interaction frequency and self-similarity trend, provides a more realistic view of the node’s influence potential. Inspired by this concept, HAC-Rank algorithm has been proposed for identification of initial adopters based on both their connections and past behaviour. Furthermore, a Hurst-based Influence Maximization (HBIM) model for diffusion, wherein a node’s activation depends upon its connections and the self-similarity trend exhibited by its past activity, has also been proposed. For assessing the self-similarity trend in a node’s activity pattern, Hurst exponent (H) has been computed. Based on the results achieved, proposed algorithm has been found to perform better than other state-of-art algorithms for initial adopter identification.

The Programmed death-1 (PD-1) and its ligand PD-L1 are critical checkpoints in the regulation of immune responses. Here the authors implicate PD-L1 signalling at lymphatic endothelium in the regulation of transendothelial migration of T cells.

Abstract Recent clinical studies show activating multiple innate immune pathways drives robust responses in infection and cancer. Biomaterials offer useful features to deliver multiple cargos, but add translational complexity and intrinsic immune signatures that complicate rational design. Here a modular adjuvant platform is created using self‐assembly to build nanostructured capsules comprised entirely of antigens and multiple classes of toll‐like receptor agonists (TLRas). These assemblies sequester TLR to endolysosomes, allowing programmable control over the relative signaling levels transduced through these receptors. Strikingly, this combinatorial control of innate signaling can generate divergent antigen‐specific responses against a particular antigen. These assemblies drive reorganization of lymph node stroma to a pro‐immune microenvironment, expanding antigen‐specific T cells. Excitingly, assemblies built from antigen and multiple TLRas enhance T cell function and antitumor efficacy compared to ad‐mixed formulations or capsules with a single TLRa. Finally, capsules built from a clinically relevant human melanoma antigen and up to three TLRa classes enable simultaneous control of signal transduction across each pathway. This creates a facile adjuvant design platform to tailor signaling for vaccines and immunotherapies without using carrier components. The modular nature supports precision juxtaposition of antigen with agonists relevant for several innate receptor families, such as toll, STING, NOD, and RIG.

Aim: To delineate and analyze the mortality from COVID -19 in our institute during the devastating second wave of pandemic. Settings and Design: A retrospective cohort analysis. Methods and Materials: A comprehensive mortality analysis of 142 laboratory-confirmed severe acute respiratory syndrome coronavirus 2-infected deceased patients from our hospital's medical records was done. These patients presented with severe disease at the time of admission and were managed in intensive care units. Statistical Analysis Used: Statistical Package for Social Sciences software, IBM manufacturer, Chicago, USA, version 21.0 was used. Results: The number of deceased males (82, 62.6%) was higher than females (53, 37.3%). Median age of deceased patient was 57 (44.25–69.75) years. Most frequent comorbidities were diabetes mellitus (42, 29.6%) and hypertension (41, 28.9%). Most common symptoms being shortness of breath (137, 96.5%), fever (94, 66.2%) and cough (73, 51.4%). Median peripheral capillary oxygen saturation (SpO2) at time of admission was 86% (77.25–90). Median time interval from symptom onset to admission in hospital was 3 (2.25–5) days. Neutrophil lymphocyte ratio was more than 5 in 117 (90.7%) patients. Complications seen were acute respiratory distress syndrome in 82.3%, acute liver injury in 58.4%, acute kidney injury in 26.7%, sepsis in 13.3% and acute cardiac injury in 12% patients. The median high-resolution computed tomography score was 20 (17–22). Conclusions: Male and elderly patients with underlying comorbidities had poorer outcome and involvement of multiple organ systems was common. A short time interval between symptom onset and admission/mortality, particularly encountered was worrisome.

Climate change is the biggest challenge faced by the world. It has already started affecting the weather patterns leading to disruption of normal life. Detecting change helps to monitor and plan the Earth’s resources in an efficient manner. An important factor in climate change is the change in the green cover. Non-availability of standard datasets and limited labeled data points makes it difficult to attain high accuracies in change detection. In this paper, we have proposed a modified ensemble of extreme learning machines (mAEELM) for change detection in green cover to increase the accuracy of the change detection process. It uses Extreme Learning Machine (ELM) as the base classifier. Different ELMs are trained with different configuration so that they have different learning capabilities. These ELMs are combined to create an ensemble and it is then adapted based on the accuracy of the individual ELMs. The ensemble is then pruned to eliminate the ELMs which are not contributing towards the overall result of the ensemble, to make it more efficient. The proposed algorithm has been applied for detecting change on two areas of Gandhuan, Punjab and Chaparkaura Kham, Uttar Pradesh, India. The algorithm shows an average accuracy of 97.8% on both the datasets.

The lymph node (LN) is the primary site of alloimmunity activation and regulation during transplantation. Here, we investigated how fibroblastic reticular cells (FRCs) facilitate the tolerance induced by anti-CD40L in a murine model of heart transplantation. We found that both the absence of LNs and FRC depletion abrogated the effect of anti-CD40L in prolonging murine heart allograft survival. Depletion of FRCs impaired homing of T cells across the high endothelial venules (HEVs) and promoted formation of alloreactive T cells in the LNs in heart-transplanted mice treated with anti-CD40L. Single-cell RNA sequencing of the LNs showed that anti-CD40L promotes a Madcam1+ FRC subset. FRCs also promoted the formation of regulatory T cells (Tregs) in vitro. Nanoparticles (NPs) containing anti-CD40L were selectively delivered to the LNs by coating them with MECA-79, which binds to peripheral node addressin (PNAd) glycoproteins expressed exclusively by HEVs. Treatment with these MECA-79–anti-CD40L-NPs markedly delayed the onset of heart allograft rejection and increased the presence of Tregs. Finally, combined MECA-79–anti-CD40L-NPs and rapamycin treatment resulted in markedly longer allograft survival than soluble anti-CD40L and rapamycin. These data demonstrate that FRCs are critical to facilitating costimulatory blockade. LN-targeted nanodelivery of anti-CD40L could effectively promote heart allograft acceptance.

Perilla seed meal (PSM) is the by-product of the oil extraction industry and a potential source of bioactive compounds. Pulsed electric field, a non-thermal technology, can be used to recover heat labile bioactive compounds from plant materials such as perilla seed meal. This study found that pulsed electric field (PEF) assisted alkaline extraction influenced the protein content and antioxidant activity of perilla seed meal (PSM). Among all PEF parameters, electric field strength (EFS) and pulse width (PW) were found to be the most significant as judged by F-value. Consequently, a central composite rotatable experimental design was applied to investigate the effect of electric field strength (EFS) and pulse width against protein content, antioxidant activity, and total phenolic content (TPC) of PEF treated PSM extract. Compared to conventional alkaline extraction, an increase in the yield of protein content by 10.58%, antioxidant activity by 7.48%, and total phenolic content by 21.59% was recorded at the optimal values of electric field strength (4 kV/cm) and pulse width (120 µs). Moreover, Karl pearson correlational analysis revealed a strong relationship (linear, R2=0.963) between antioxidant activity and total phenolic content. The validation was done at 95% confidence level for which the predicted values were compared with the actual experimental values, and the means were found to be insignificantly different from each other (p > 0.05). Industrial relevance: Non-thermal extraction techniques such as pulsed electric field used in this study can be used for the recovery of valuable compounds from the food materials especially heat sensitive compounds. PEF treatment increased the extractability of the water-soluble compounds from the perilla seed meal (PSM) samples and increased the recovery of valuable compounds from PSM while maintaining the nutritional and functional viability. Hence, this technology is having the potential to be used as assistant technology for the extraction of heat sensitive components from the plant cells which may find its applications in neutraceutical and pharmaceutical industries.

Lymph node (LN) fibroblastic reticular cells (FRCs) define LN niches and regulate lymphocyte homeostasis through producing diverse extracellular matrix (ECM) components. We examined the role of ECM laminin α4 (Lama4) using FRC-Lama4 conditional KO Pdgfrb-Cre–/– × Lama4fl/fl mice. Single-cell RNA-sequencing (scRNA-Seq) data showed the promoter gene Pdgfrb was exclusively expressed in FRCs. Depleting FRC-Lama4 reduced Tregs and dendritic cells, decreased high endothelial venules, impaired the conduit system, and downregulated T cell survival factors in LNs. FRC-Lama4 depletion impaired the homing of lymphocytes to LNs in homeostasis and after allografting. Alloantigen-specific T cells proliferated, were activated to greater degrees in LNs lacking FRC-Lama4, and were more prone to differentiate into effector phenotypes relative to the Treg phenotype. In murine cardiac transplantation, tolerogenic immunosuppression was not effective in FRC-Lama4 recipients, which produced more alloantibodies than WT. After lung transplantation, FRC-Lama4–KO mice had more severe graft rejection with fewer Tregs in their LNs. Overall, FRC-Lama4 critically contributes to a tolerogenic LN niche by supporting T cell migration, constraining T cell activation and proliferation, and promoting Treg differentiation. Hence, it serves as a therapeutic target for immunoengineering.

In this paper the authors have tried to measure the impact of different variants of pulsating distributed denial of service attacks on the self-similar nature of the network traffic and to see if the variation in the H index could be used for distinguishing them from normal network traffic. Keywords: Network attacks, Anomalies, DDoS, Rate-based detection

The Internet of Things (IoT) is the next era of communication. Using the IoT, physical objects can be empowered to create, receive, and exchange data in a seamless manner. Various IoT applications focus on automating different tasks and are trying to empower the inanimate physical objects to act without any human intervention. The existing and upcoming IoT applications are highly promising to increase the level of comfort, efficiency, and automation for the users. To be able to implement such a world in an ever-growing fashion requires high security, privacy, authentication, and recovery from attacks. In this regard, it is imperative to make the required changes in the architecture of the IoT applications for achieving end-to-end secure IoT environments. In this paper, a detailed review of the security-related challenges and sources of threat in the IoT applications is presented. After discussing the security issues, various emerging and existing technologies focused on achieving a high degree of trust in the IoT applications are discussed. Four different technologies, blockchain, fog computing, edge computing, and machine learning, to increase the level of security in IoT are discussed.

Summary: Regulatory T cells (Tregs) express high levels of cell surface lymphotoxin alpha beta (LTα1β2) to activate the LT beta receptor (LTβR) on the lymphatic endothelial cells (LECs), modulating LEC adhesion molecules, intercellular junctions, and chemokines. We demonstrate a role for Tregs through this pathway to condition the permissiveness of lymphatic endothelia for transendothelial migration (TEM), thus gating leukocyte traffic. Human Tregs share the same property with murine Tregs. Activation of TLR2 on Tregs during inflammation specifically augments LTα1β2-LTβR signaling, which further enhances the permissiveness of LECs to facilitate TEM. The conditioning of endothelia may promote the resolution of inflammation by directing leukocytes out of tissues to lymphatic vessels and draining lymph nodes (dLNs). Thus, Tregs interact with lymphatic endothelia under homeostasis and inflammation and dictate endothelial permissiveness and gating mechanisms for subsequent leukocyte migration through endothelial barriers. : Piao et al. demonstrate that Tregs condition lymphatic endothelial cells (LECs) to be more permissive for the transendothelial migration (TEM) of other leukocytes. Activation of Toll-like receptor 2 on Tregs during inflammation specifically augments Treg LTα1β2 expression to intensify LTβR signaling in LECs for enhanced immune cell TEM. Keywords: regulatory T cells, lymphatic endothelial cells, Toll-like receptor 2, lymphotoxin, transendothelial migration

Lymphotoxin beta receptor (LTβR) signalling regulates leukocyte migration through the lymphatic endothelial layers. Here, the authors show that treatment of an LTβR-derived decoy peptide can target the non-classical NFκB pathway to inhibit T cell and dendritic cell migration and ameliorate contact hypersensitivity in mouse models.

The pleiotropic functions of lymphotoxin (LT)β receptor (LTβR) signaling are linked to the control of secondary lymphoid organ development and structural maintenance, inflammatory or autoimmune disorders, and carcinogenesis. Recently, LTβR signaling in endothelial cells has been revealed to regulate immune cell migration. Signaling through LTβR is comprised of both the canonical and non-canonical-nuclear factor κB (NF-κB) pathways, which induce chemokines, cytokines, and cell adhesion molecules. Here, we focus on the novel functions of LTβR signaling in lymphatic endothelial cells for migration of regulatory T cells (Tregs), and specific targeting of LTβR signaling for potential therapeutics in transplantation and cancer patient survival.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Nonstructural protein 5A (NS5A) of hepatitis C virus (HCV) serves dual functions in viral RNA replication and virus assembly. Here, we demonstrate that HCV replication complex along with NS5A and Core protein was transported to the lipid droplet (LD) through microtubules, and NS5A-Core complexes were then transported from LD through early-to-late endosomes to the plasma membrane via microtubules. Further studies by cofractionation analysis and immunoelectron microscopy of the released particles showed that NS5A-Core complexes, but not NS4B, were present in the low-density fractions, but not in the high-density fractions, of the HCV RNA-containing virions and associated with the internal virion core. Furthermore, exosomal markers CD63 and CD81 were also detected in the low-density fractions, but not in the high-density fractions. Overall, our results suggest that HCV NS5A is associated with the core of the low-density virus particles which exit the cell through a preexisting endosome/exosome pathway and may contribute to HCV natural infection.