Immuno

Catastrophic antiphospholipid syndrome (CAPS) is a rare clinical form of antiphospholipid syndrome (APS) associated with life-threatening complications due to simultaneous thrombosis that may affect small and large vessels. It may be localized to the venous and/or arteries at the same time, and there are not available guidelines based on randomized clinical trials or large series. We here report a clinical case of CAPS with onset after resolution of oligo-symptomatic infection SARS-CoV-2, that had transient improvement with warfarin after recurrent thromboses occurred despite treatment off-label with low doses of low molecular weight heparin. Furthermore, we tried to trace a line by which a multidisciplinary team may set specific timing to have follow-up because of the high morbidity, mortality, and prolonged time of hospitalization. Full article

The SARS-CoV-2 pandemic ignited global efforts to rapidly develop testing, therapeutics, and vaccines. However, the rewards of these efforts were slow to reach many low- to middle-income countries (LMIC) across the African continent and globally. Therefore, two bead-based multiplexed serological assays were developed to determine SARS-CoV-2 exposure across four counties in Liberia. This study was conducted during the summer of 2021 on 189 samples collected throughout Grand Bassa, Bong, Margibi, and Montserrado counties. Our multiplexed immunoassay (MIA) detected elevated exposure to SARS-CoV-2 and multiple variant antigens. Additionally, we detected evidence of exposure to Dengue virus serotype 2, Chikungunya virus, and the seasonal coronavirus NL63. Our multiplexed inhibition test (MINT) was developed from the MIA to observe antibody-mediated inhibition of SARS-CoV-2 spike protein binding to its cognate cellular receptor ACE-2. We detected inhibitory antibodies in the tested Liberian samples, which were collectively consistent with a convalescent serological profile. These complementary assays serve to supplement existing serological testing needs and may enhance the technical capacity of scientifically underrepresented regions globally. Full article

Around 285 million people worldwide currently have type 2 diabetes and it is projected that this number will be surpassed by 2030. Therefore, it is of the utmost importance to enhance our comprehension of the disease’s development. The regulation of diet, obesity, and inflammation in type 2 diabetes is believed to play a crucial role in enhancing insulin sensitivity and reducing the risk of onset diabetes. Obesity leads to an increase in visceral adipose tissue, which is a prominent site of inflammation in type 2 diabetes. Dyslipidemia, on the other hand, plays a significant role in attracting activated immune cells such as macrophages, dendritic cells, T cells, NK cells, and B cells to visceral adipose tissue. These immune cells are a primary source of pro-inflammatory cytokines that are believed to promote insulin resistance. This review delves into the influence of elevated dietary free saturated fatty acids and examines the cellular and molecular factors associated with insulin resistance in the initiation of inflammation induced by obesity. Furthermore, it explores novel concepts related to diet-induced inflammation and its relationship with type 2 diabetes. Full article

Macrophages are myeloid phagocytic leukocytes whose functions are to protect against infections, mediate T-cell responses, and maintain tissue homeostasis. IL-12p40 monomer is a cytokine that is largely produced by macrophages, and it has, for the longest time, been considered a largely non-functional cytokine of the IL-12 family. However, new research has emerged that demonstrates that this p40 monomer may play a bigger role in shaping immune environments. To shed light on the specific effects of p40 monomer on macrophages and their surrounding environment, we showed, through cell culture studies, qPCR, ELISA, and immunofluorescence analyses, that the direct administration of recombinant p40 monomer to RAW 264.7 cells and primary lung macrophages stimulated the production of both pro-inflammatory (TNFα) and anti-inflammatory (IL-10) signals. Accordingly, p40 monomer prevented the full pro-inflammatory effects of LPS, and the neutralization of p40 monomer by mAb a3-3a stimulated the pro-inflammatory effects of LPS. Furthermore, we demonstrated that the intranasal administration of p40 monomer upregulated TNFα⁺IL-10⁺ macrophages in vivo in the lungs of mice. Collectively, these results indicate an important immunoregulatory function of p40 monomer in the upregulation of both pro- and anti-inflammatory molecules in macrophages. Full article

Hidradenitis Suppurativa (HS) is a debilitating cutaneous disease characterized by a vicious cycle of chronic inflammation and tissue destruction that stems from disruption of the skin microbiome and abnormal activation of both the innate and adaptive immune system. A hallmark of HS pathophysiology is dysregulation of both the innate and adaptive immune system. The role of immune system dysregulation in HS development has motivated researchers to explore the utility of biologic immunomodulators. In 2015, adalimumab, a tumor necrosis factor-α inhibitor, was approved by the Food and Drug Administration (FDA) for treatment of moderate-to-severe HS in the US. In 2023, secukinumab, an interleukin-17A (IL-17A) inhibitor, was approved by the European Medicines Agency for treatment of moderate-to-severe HS in Europe. Ongoing clinical trials have shown promising clinical responses to targeted therapies against other pro-inflammatory cytokines including IL-17, IL-12, IL-1, IL-36, IL-6, IL-10, interferon γ, C5a, and Janus kinase (JAK). We provide an update on the efficacy and clinical usage of targeted biologics in HS treatment. Full article

The kinetic responses of leukocyte subsets to exercise and their recovery may serve as indicators of immunological resilience. These time-dependent responses were investigated in healthy young men using a bicycle ergometer test. Fifteen recreationally active male cyclists (20–35 years, VO_2max 56.9 ± 3.9 mL kg⁻¹ min⁻¹) performed four exercise protocols with a 1 h duration in a cross-over design: at 70% of the maximal workload (Wmax) in a hydrated and a mildly dehydrated state, at 50% of the Wmax, and intermittently at 85/55% of the Wmax in blocks of 2 min. The numbers of lymphocytes, monocytes, neutrophils, eosinophils, basophils, thrombocytes, and NK cells (CD16 and CD56) were measured at different time points up to 24 h post-exercise. The total leukocyte counts and those of most subsets increased from the start of the exercise, peaking after 30–60 min of exercising. The neutrophil numbers, however, peaked 3 h post-exercise. The CD16^brightCD56^dim NK cells showed a 1.5-fold increase compared to the CD16^brightCD56^bright NK cells. Other than for MCP-1, no significant differences were found in the serum cytokine levels. Our results show that exercise intensity is reflected in different time-dependent changes in leukocyte subsets, which supports the concept that the exchange of immune cells between peripheral blood and tissues contributes to enhanced immune surveillance during strenuous exercise. Full article

Tumor necrosis factor α (TNF-α) is a multifunctional cytokine protein acknowledged as a vital mediator in cell differentiation, proliferation, and survival. Additionally, TNF-α is a crucial component of the host’s defense by mediating inflammatory and immune responses against various aggressive agents, including viruses, bacteria parasites, and tumors. However, excessive production can be detrimental to the body and is also implicated in developing several inflammatory and immune-mediated disorders. Therefore, there is great interest in studying its role and its modulation, in various diseases, both in in vitro, in vivo, and in silico experiments. In this review, we evaluated the structures of proteins related to TNF-α available in public databases. In addition, we described the main antibodies blocking this cytokine and its applications and commented on the potential of naturally produced binding molecules, such as TNF-α-binding proteins produced by ticks. We also discuss the role of structural bioinformatics techniques in understanding the mechanisms of chronic inflammatory diseases related to TNF-α. We hope that the data presented in this review will be useful for studies that aim to better understand the mechanisms of the interactions of TNF-α with other proteins and will lead to new drugs or treatments. Full article

Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by thrombotic or obstetric events occurring in individuals who have persistent antiphospholipid antibodies. Catastrophic antiphospholipid syndrome (CAPS) is a rare and potentially fatal form of APS characterized by severe thrombotic complications occurring in multiple organs over a short period of time or simultaneously. CAPS is associated with a high (50%) death rate. Infections, multi-organ failure, and cerebral and heart thrombosis represent the main complications of this syndrome. Generally, anticoagulants, glucocorticoids, therapeutic plasmapheresis (TPE), and intravenous immunoglobulin (IVIG) are used in combination for treatment. Multidisciplinary care involving different specialists from hematology, rheumatology, nephrology, infectious disease, critical care, and obstetrics is often required due to the complexity of the disease. Recent data emphasize the effectiveness of biologics such as anti-TNF-a monoclonal antibodies (adalimumab, certolizumab), anti-CD38 monoclonal antibody (daratumumab), BAFF/Blys inhibitor (belimumab), and BTK inhibitor (zanubrutinib) against CAPS. In order to understand the underlying causes of CAPS, one future possibility involves investigating and characterizing the hereditary and acquired risk factors associated with CAPS. Full article

Liver fibrosis is a complex, dynamic process associated with a broad spectrum of chronic liver diseases and acute liver failure, characterised by the dysregulated intrahepatic production of extracellular matrix proteins replacing functional liver cells with scar tissue. Fibrosis progresses due to an interrelated cycle of hepatocellular injury, triggering a persistent wound-healing response. The accumulation of scar tissue and chronic inflammation can eventually lead to cirrhosis and hepatocellular carcinoma. Currently, no therapies exist to directly treat or reverse liver fibrosis; hence, it remains a substantial global disease burden. A better understanding of the intricate inflammatory network that drives the initiation and maintenance of liver fibrosis to enable the rationale design of new intervention strategies is required. This review clarifies the most current understanding of the hepatic fibrosis cellular network with a focus on the role of regulatory T cells, and a possible trajectory for T cell immunotherapy in fibrosis treatment. Despite good progress in elucidating the role of the immune system in liver fibrosis, future work to better define the function of different immune cells and their mediators at different fibrotic stages is needed, which will enhance the development of new therapies. Full article

Zaire ebolavirus (EBOV) poses a significant threat to public health due to its high case fatality rate and epidemic potential. This is further complicated by the lack of precise immune correlates of protection and difficulties in conducting in vivo animal studies due to species specificity of Ebola virus disease (EVD) and classification as a biosafety level 4 pathogen. Related ebolaviruses have also contributed to the public health threat; Uganda recently experienced an outbreak of Sudan ebolavirus, which also had a high case fatality rate. Vaccination targeting EBOV has demonstrated significant efficacy; however, the protective cellular and humoral responses at play are still poorly understood. Vaccination for vulnerable populations such as pregnant women, young children, and immunocompromised individuals is still limited. Understanding vaccine correlates of protection (vCOP) is key to developing alternative vaccination strategies for these groups. Components of immunity such as neutralizing antibody and cell-mediated immunity are likely responsible for protective responses; however, existing research fails to fully define their roles in protection. Here we investigated vaccine-elicited antibody avidity as a potential correlate of protection and to further characterize the contribution of antibody avidity in protective and nonprotective vaccine responses. Full article

Advancements in sequencing and screening technology have made monoclonal antibodies more accessible, cost-effective, and precise. These drugs effectively target pathogens and cancer cells and even regulate metabolic pathways by focusing on specific intermediates. Monoclonal antibodies play a key role in mitigating a rise in occupation-related cancers, neurodegenerative disorders, and multidrug-resistant organisms. Here, we review the origins, mechanisms, and applications of this important drug class and explore future avenues for research. Full article

The impact of pre-existing common cold coronavirus (CCCoV) antibodies (Abs) on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immune responses and pathogenesis remains poorly defined. We evaluated these associations in a cohort of hospitalized patients with COVID-19 and respiratory failure of varying severity. Patients with respiratory failure from other causes (non-COVID-19) were evaluated as controls. We demonstrated a positive correlation between levels of CCCoV and SARS-CoV-2 Abs using CCCoV and SARS-CoV-2 N and S protein peptide-specific ELISA. Consistent with the above, moderately increased levels of CCCoV-specific Abs in non-COVID-19 vs. COVID-19 patients suggest potential protective effects. Further, higher SARS-CoV-2 N protein-specific and CCCoV Ab levels were observed among surviving vs. non-surviving COVID-19 positive patients. However, the highest SARS-CoV-2 N and S protein-specific IgG and IgA Ab levels were noted in the patients with the most severe clinical disease. Finally, advanced age, cancer and immunosuppression were associated with significantly higher mortality and reduced SARS-CoV-2 and CCCoV Ab levels. Thus, our data highlight that sufficient SARS-CoV-2 N protein-specific Ab responses improve clinical outcomes in severely ill COVID-19 patients. We also confirmed that pre-existing CCCoV-specific Abs do not inhibit the SARS-CoV-2 Ab response and may further reduce the prevalence and/or severity of COVID-19. Full article

Bone marrow is known as the site of hematopoiesis. What is not being described in textbooks of immunology is the fact that bone marrow is not only a generative, but also an antigen-responsive, immune organ. It is also a major storage site for antigen-specific memory B and T cells. That bone marrow is a priming site for T cell responses to blood borne antigens was discovered exactly 20 years ago. This review celebrates this important discovery. The review provides a number of examples of medical relevance of bone marrow as a central immune system, including cancer, microbial infections, autoimmune reactions, and bone marrow transplantation. Bone marrow mesenchymal stem cell-derived stromal cells provide distinct bone marrow niches for stem cells and immune cells. By transmitting anti-inflammatory dampening effects, facilitating wound healing and tissue regeneration mesenchymal stem cells contribute to homeostasis of bone and other tissues. Based on the evidence presented, the review proposes that bone marrow is a multifunctional and protective immune system. In an analogy to the central nervous system, it is suggested that bone marrow be designated as the central immune system. Full article

Immunoglobulin-like transcript 4 (ILT4) is an immunosuppressive molecule predominantly expressed on myeloid cells. Recent studies combining ILT4 suppression with programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) blockade have shown promising signs of activity in immune checkpoint inhibitor refractory patients. We theorized that coupling ILT4 and PD-1/PD-L1 blockade in a bispecific antibody (bsAb) may provide greater immune activating properties than combining the individual mAbs due to enhanced bridging of APCs to T cells. To test this approach, we developed CDX-585, a tetravalent ILT4xPD-1 IgG1-scFv bsAb from novel PD-1 and ILT-4 mAbs. CDX-585 is a potent antagonist of both PD-1 and ILT4. CDX-585 promotes M1 macrophage polarization and enhances pro-inflammatory cytokine secretion in response to lipopolysaccharide or CD40 agonist mAb treatment. In mixed lymphocyte reaction (MLR) assays, CDX-585 is more potent than the combination of parental antibodies. In a humanized NCG mouse SK-MEL-5 tumor model, CDX-585 exhibits greater antitumor activity than the combination of parental mAbs. A pilot study of CDX-585 in cynomolgus macaques confirmed a mAb-like pharmacokinetic profile without noted toxicities. These studies demonstrate that CDX-585 effectively combines ILT4 and the PD-1 blockade into one molecule that is more potent than the combination of the parental antibodies, providing the rationale to advance this bsAb into clinical studies. Full article

Osteoarthritis (OA) is the most common degenerative joint disease that causes chronic pain and disability. Different innate immune components, including macrophages, T cells, and neutrophils, participate in OA pathophysiology. Neutrophils are the most abundant circulating leukocytes with multiple specialized functions contributing to innate and adaptive immune functions. Although neutrophils produce proinflammatory cytokines and chemokines, reactive oxygen species (ROS), matrix-degrading enzymes, and neutrophil extracellular traps (NET) that promote joint degradation as the first recruit cells in an inflamed joint, these cells also play an important role in joint repair by regulating the immune response, releasing anti-inflammatory factors, and activating certain protective genes. In this review, various aspects of neutrophil biology, their role in inflammation and its association with OA, and possible therapeutic approaches to target neutrophils for the treatment of OA are described. Since neutrophils play a complex role in the pathophysiology of osteoarthritis, contributing to joint degradation as well as joint repair, targeting these cells is likely to pave the way for a potential therapeutic approach for the management of OA. Future studies are needed to investigate the use of targeted therapies to modulate neutrophil function and identify their subpopulations that are associated with osteoarthritis progression or response to treatment. Full article

Chemotherapy-refractive multiple myeloma (MM) is serious and life-threatening, and better treatments are urgently needed. BCMA is a prominent marker on the cell surface of MM cells, rendering it an accepted target for antibody therapy. Considering that MM is a liquid tumor and immunotherapy has enjoyed success against leukemia, we devise an approach designed to enhance NK cell activity against MM. Ordinarily, NK cells function to naturally survey the body and eliminate malignant cells. Our platform approach is designed to enhance NK function. A tri-specific immune-engaging TriKE is manufactured, consisting of a camelid nanobody VHH antibody fragment recognizing CD16 expressed on NK cells and an scFv antibody fragment specifically recognizing BCMA. These two fragments are crosslinked by the human cytokine interleukin-15 (IL-15) known to have prominent activating effects on NK cells. The molecule, when tested by flow cytometry, shows activation of NK cells in their numbers and activity. Additionally, the molecule demonstrates anti-cancer effects in an in vivo xenograft model of human MM. We believe that the drug will have the capability of enhancing NK cells at the site of the immune synapse, i.e., the effector:target cell interface, and this will promote cancer remissions. Full article

In terms of the global burden of disease, helminthiasis is the most common infectious disease in the world. In response to the disease, the human host develops an immunological response that occurs predominantly through the action of T helper 2 (Th2) cells and the interleukins IL-4, IL-5 and IL-13. However, other types of Th cells, such as Th9, are also involved in the defense against helminths, with the IL-9 produced by these cells promoting the induction of mastocytosis and the increased production of IgG1 and IgE, in addition to the increase in intestinal contractility that promotes the expulsion of worms. Together, IL-9 and IL-10, which is also produced by Th9, induce a type 2 inflammatory response characterized by the coordinated actions of innate lymphoid cells, mast cells, basophils and other cells that work together toward a single objective: the reduction of the parasitic burden. This review presents the latest findings on Th9 effector mechanisms in helminthic infections. Full article

The 19th century saw the development of vaccines, which were biological preparations designed to enhance immunity against specific diseases. Edible vaccines function by stimulating both systemic and mucosal immune responses against foreign pathogens, and they may potentially protect the host from autoimmunity. The mucosal surfaces provide a convenient and rapid route for delivering therapeutic small molecules. This is due to their large surface areas and easy administration. The effectiveness of mucosal immunization relies on the fact that mucous membranes represent the body’s largest immunogenic organ. Within this interface, there is a well-organized lymphatic structure known as MALT (mucosa-associated lymphoid tissue), which includes both T and B cells and encompasses the adaptive arms of the immune system. Oral vaccines specifically stimulate immune responses in the gut-associated lymphoid tissue (GALT), which consists of lymph nodes, Payer’s patches (where B cells make up about 75% of the population and T cells account for approximately 20%), and isolated lymphoid follicles within the gastrointestinal tract (GIT). However, a significant challenge in developing vaccines is the rapid degradation of antigens within the harsh environment of the digestive tract, which hampers effective protein delivery to the GIT. In light of recent proteomic analysis revealing strong up-regulation of the tryptophan catabolic enzyme indoleamine 2, 3-dioxygenase (IDO1) in DCs inoculated with the Cholera toxin B-subunit-Insulin fusion protein vaccine (CTB-INS), we are interested in investigating the effects of transgene integration into a selected plant cell as an edible vaccine. Full article

Breast cancer is the most commonly diagnosed cancer in women and is a leading cause of cancer death in women worldwide. Despite the available treatment options, such as surgery, chemotherapy, radiotherapy, endocrine therapy and molecular targeted therapy, breast cancer treatment remains a challenge. The advent of immunotherapy has revolutionized the treatment of breast cancer as it utilizes the host’s immune system to directly target tumor cells. In this literature review, we aim to summarize the recent advancements made in using immunotherapy for treating breast cancer patients. We discuss the different types of existing immunotherapies for breast cancer, including targeted therapy using monoclonal antibodies against breast cancer specific antigens and the use of immune checkpoint inhibitors to elicit an immune response against cancer cells. Finally, we consider the development of breast cancer vaccines that train the immune system to specifically recognize cancer cells and the future perspectives of immunotherapy for breast cancer. Full article