Elevated Antibody Levels Research Articles

Protective efficacy and immune responses of largemouth bass (Micropterus salmoides) immunized with an inactivated vaccine against the viral hemorrhagic septicemia virus genotype IVa

Viral hemorrhagic septicemia virus (VHSV) poses a significant threat to the aquaculture industry, prompting the need for effective preventive measures. Here, we developed an inactivated VHSV and revealed the molecular mechanisms underlying the host's protective response against VHSV. The vaccine was created by treating VHSV with 0.05 % formalin at 16 °C for 48 h, which was determined to be the most effective inactivation method. Compared with nonvaccinated fish, vaccinated fish exhibited a remarkable increase in survival rate (99 %) and elevated levels of serum neutralizing antibodies, indicating strong immunization. To investigate the gene changes induced by vaccination, RNA sequencing was performed on spleen samples from control and vaccinated fish 14 days after vaccination. The analysis revealed 893 differentially expressed genes (DEGs), with notable up-regulation of immune-related genes such as annexin A1a, coxsackievirus and adenovirus receptor homolog, V-set domain-containing T-cell activation inhibitor 1-like, and heat shock protein 90 alpha class A member 1 tandem duplicate 2, indicating a vigorous innate immune response. Furthermore, KEGG enrichment analysis highlighted significant enrichment of DEGs in processes related to antigen processing and presentation, necroptosis, and viral carcinogenesis. GO enrichment analysis further revealed enrichment of DEGs related to the regulation of type I interferon (IFN) production, type I IFN production, and negative regulation of viral processes. Moreover, protein-protein interaction network analysis identified central hub genes, including IRF3 and HSP90AA1.2, suggesting their crucial roles in coordinating the immune response elicited by the vaccine. These findings not only confirm the effectiveness of our vaccine formulation but also offer valuable insights into the underlying immunological mechanisms, which can be valuable for future vaccine development and disease management in the aquaculture industry.

Skin appendage abnormalities in hypothyroidism: understanding and management

Introduction and purpose Thyroid ailments are frequently encountered in medical practice, often intertwined with a variety of conditions that may or may not share common underlying factors. Among the organs profoundly influenced by these disorders is the skin, which manifests a diverse array of clinical presentations. However, the exact changes in the structure of skin appendages have not been well studied. Changes in hair structure or nail findings may be helpful in early diagnosis of thyroid disorders and therefore are important for dermatologist education. Hair loss can be a very uncomfortable and embarrassing ailment. Many diseases, nutritional deficiencies, stress and other factors can affect the hair condition and even induce its falling out. This review seeks to explore the numerous skin disorders arising directly or indirectly from thyroid irregularities, offering an updated understanding of the interplay between thyroid function and skin health. State of Knowledge It is well-established in scientific literature that thyroid gland disorders, particularly hypothyroidism, induce metabolic deceleration, influencing the inadequate nourishment of skin appendages, resulting in skin dryness and fragility. Patients commonly report pallor, cold intolerance, and deteriorating hair and nail quality. Conclusion We noticed strong correlation between hair loss and the autoimmune process during the dysfunction of thyroid. Euthyroidism plays an important role in hair cycle and any changes can disturb its proper development. In Hashimoto disease elevated levels of antibodies negatively influence hair cycle by excessively inducing telogen phase. Moreover, the blood vessels of the skin constrict disrupting the blood flow which affects hair follicles.

Developmentand validation of carbodiimide-activated ELISA plate for quantifying IgG levels against Streptococcus pneumoniae capsular polysaccharides.

Background:Conventional microtiter plates lack the surface strength needed for effective binding of pneumococcalpolysaccharide antigens. This study tackles the limitation by altering the surface of polystyrene plates through carbodiimide activation under acidic pH conditions.Method:The microtiter plates were activated with carbodiimide coupling agents, N,N'-Dicyclohexylcarbodiimide (DCC) and N-Hydroxysuccinimide (NHS). They were subsequently coated with 13 pneumococcal antigens at a concentration of 5 μg/ml with a pH of 3.5. The IgG antibody titer was assessed utilizing the World Health Organization (WHO) ELISA protocol for 30 human serum samples. In addition, validation experiments were conducted to evaluate specificity and precision.Results: The modified plates exhibited two-times higher antibody titers compared to conventional plates across all 13 serotypes. Observations revealed elevated antibody levels, with geometric concentrations ranging between 0.96 μg/ml and 4.24 μg/ml.Conclusion:Carbodiimide activation and acidic pH modification of microtiter plates enhance sensitivity and specificity in detecting pneumococcal antibodies, critical for vaccination planning and immunity assessment.

Comparative analysis through propensity score matching in thyroid cancer: unveiling the impact of multiple malignancies.

The incidence of thyroid cancer is on the rise worldwide, with childhood exposure to radiation being the sole acknowledged catalyst for its emergence. Nonetheless, numerous other factors that may pose risks are awaiting thorough examination and validation. This retrospective study aims to explore the malignancies linked to thyroid cancer and contrast the survival rates of those afflicted with a solitary tumor versus those with multiple primary neoplasms (MPN). This retrospective study examined data from King Hussein Cancer Center (KHCC), Jordan. Among 563 patients diagnosed with thyroid cancer, 30 patients had thyroid malignancy as part of MPN. For a 1:3 propensity score-matched analysis, 90 patients with only a primary thyroid malignancy were also enrolled. Hematologic and breast malignancies were among the most frequent observed cancers alongside thyroid neoplasm. Patients who had MPN were diagnosed at older age, had higher body mass index and presented with higher thyroglobulin antibody levels (p < 0.05 for each). Additionally, MPN patient displayed a stronger family history for cancers (p= 0.002). A median follow-up duration of 135 months unveiled that MPN patients faced a worse 5-year survival compared to their counterparts with a singular neoplasm (87% vs 100% respectively; p < 0.01). However, no distinction emerged in the 5-year event-free survival between these two groups. MPN correlates with a significantly altered survival outcome of thyroid cancer patients. The diagnosis of thyroid carcinoma at an older age, accompanied by elevated initial thyroglobulin antibody levels and a notable familial predisposition, may raise concerns about the potential occurrence of synchronous or metachronous tumors.

Antibody longevity and waning following COVID-19 vaccination in a 1-year longitudinal cohort in Bangladesh

COVID-19 vaccines have been effective in preventing severe illness, hospitalization and death, however, the effectiveness diminishes with time. Here, we evaluated the longevity of antibodies generated by COIVD-19 vaccines and the risk of (re)infection in Bangladeshi population. Adults receiving two doses of AstraZeneca, Pfizer, Moderna or Sinopharm vaccines were enrolled at 2–4 weeks after second dosing and followed-up at 4-monthly interval for 1 year. Data on COVID-like symptoms, confirmed COVID-19 infection, co-morbidities, and receipt of booster dose were collected; blood was collected for measuring spike (S)- and nucleocapsid (N)-specific antibodies. S-specific antibody titers reduced by ~ 50% at 1st follow-up visit and continued to decline unless re-stimulated by booster vaccine dose or (re)infection. Individuals infected between follow-up visits showed significantly lower S-antibody titers at preceding visits compared to the uninfected individuals. Pre-enrolment infection between primary vaccination dosing exhibited 60% and 50% protection against reinfection at 5 and 9 months, respectively. mRNA vaccines provided highest odds of protection from (re)infection up to 5 months (Odds Ratio (OR) = 0.08), however, protection persisted for 9 months in AstraZeneca vaccine recipients (OR = 0.06). In conclusion, vaccine-mediated protection from (re)infection is partially linked to elevated levels of S-specific antibodies. AstraZeneca vaccine provided the longest protection.

Desensitization therapy for elevated donor-specific antibody levels in haploidentical transplantation in Chilean patients

Allogeneic stem cell transplantation (ALOSCT) is curative for several hematological diseases. Unrelated donors and cord blood stem cells are valid options but haploidentical donors (HAPLO) have been considered the main source of stem cells in several countries, partly due to easy access and low cost of the transplantation process. Unfortunately, some patients have antibodies against the HLA epitopes from family haploidentical donors (donor-specific antibodies [DSA]) which are associated with engraftment failure and lethality. A few strategies exist to reduce or eliminate HLA antibodies that bind to these receptors. In this study, we present our experience with DSA desensitization by retrospectively examining a cohort from our hospital program. Between 2012 and 2023, we performed 243 ALOSCTs, of which 142 were from HAPLO and 56 were from unrelated donors. Nine patients (7%) had elevated DSA levels, most of which were female patients and mostly HAPLO. The median fluorescence intensity for these patients was 22,490 (19,000-28,560). Most of these high DSA patients (80%) received a desensitization procedure that involves plasmapheresis, rituximab, and immunoglobulin. The remaining 20% had severe infections during transplantation, and received rituximab monotherapy instead. The median dose of stem cells infused was 6.5 x 10^6 CD34/kg. Graft-versus-host disease (GVHD) preventative measures for all patients involved post-transplantation cyclophosphamide. Primary graft failure was observed in 45% of DSA elevated patients. For the remaining patients, median granulocyte and platelet engraftment were 14 d (12-16) and 16 d (13-18), respectively. Mortality in patients who did not receive engraftment was 100%. The incidence of mild, chronic GVHD was 15%. In conclusion, the desensitization of DSA in patients provided a 55% rate of engraftment and survival. However, a 45% rate of primary graft failure continued to pose a challenge in patients with DSA and required the development of improved strategies to reduce elevated transplant-related mortality.

LAG3 regulates antibody responses following kidney transplantation

Abstract Lymphocyte activation gene-3 (LAG3) is a coinhibitory receptor expressed by a range of immune cells. The immunomodulatory potential of LAG3 is being explored in cancer and autoimmunity fields but not in transplantation. Using our mouse kidney transplant models we sought to address the role of LAG3 in graft rejection. Untransplanted LAG3-/- mice have elevated heterologous immunity against a panel of alloantigens. Recipient LAG3 deficiency results in rapid rejection of MHC-mismatched renal allografts that are spontaneously accepted by WT recipients, with graft histology characteristic of antibody mediated rejection (ABMR). Antagonistic LAG3 antibody treatment of WT recipients enhanced anti-donor immune responses and induced kidney damage typical of chronic rejection, indicating that LAG3 regulates de novo alloresponses. Recipient B cell depletion, but not CD8+ T cells, prevented kidney allograft rejection in LAG3-/- recipients further supporting ABMR as the mechanism of graft loss. Posttransplant, follicular T cells and plasma cells are among LAG3 expressing immune cells. To identify the mechanism we used T or B cell conditional LAG3 knockout recipients, neither reject the allograft but both had elevated levels of donor specific antibodies (DSA), indicating LAG3 expression on either T or B cells is sufficient to regulate anti-donor humoral immunity. Our results identify LAG3 as a regulator of DSA following kidney transplantation and a potential therapeutic target for ABMR.

JMJD6 Autoantibodies as a Potential Biomarker for Inflammation-Related Diseases.

Inflammation is closely associated with cerebrovascular diseases, cardiovascular diseases, diabetes, and cancers, and it is accompanied by the development of autoantibodies in the early stage of inflammation-related diseases. Hence, it is meaningful to discover novel antibody biomarkers targeting inflammation-related diseases. In this study, Jumonji C-domain-containing 6 (JMJD6) was identified by the serological identification of antigens through recombinant cDNA expression cloning. In particular, JMJD6 is an antigen recognized in serum IgG from patients with unstable angina pectoris (a cardiovascular disease). Then, the serum antibody levels were examined using an amplified luminescent proximity homogeneous assay-linked immunosorbent assay and a purified recombinant JMJD6 protein as an antigen. We observed elevated levels of serum anti-JMJD6 antibodies (s-JMJD6-Abs) in patients with inflammation-related diseases such as ischemic stroke, acute myocardial infarction (AMI), diabetes mellitus (DM), and cancers (including esophageal cancer, EC; gastric cancer; lung cancer; and mammary cancer), compared with the levels in healthy donors. The s-JMJD6-Ab levels were closely associated with some inflammation indicators, such as C-reactive protein and intima-media thickness (an atherosclerosis index). A better postoperative survival status of patients with EC was observed in the JMJD6-Ab-positive group than in the negative group. An immunohistochemical analysis showed that JMJD6 was highly expressed in the inflamed mucosa of esophageal tissues, esophageal carcinoma tissues, and atherosclerotic plaques. Hence, JMJD6 autoantibodies may reflect inflammation, thereby serving as a potential biomarker for diagnosing specific inflammation-related diseases, including stroke, AMI, DM, and cancers, and for prediction of the prognosis in patients with EC.

Exacerbated lung inflammation in offspring with high maternal antibody levels following secondary RSV exposure.

Respiratory syncytial virus (RSV) is the primary cause of bronchiolitis-related hospitalizations among children under 5 years of age, with reinfection being common throughout life. Maternal vaccination has emerged as a promising strategy, delivering elevated antibody levels to newborns for immediate protection. However, limited research has explored the protective efficacy of maternal antibodies (matAbs) against secondary RSV infections in offspring. To address this gap, we employed a mouse model of maternal RSV vaccination and secondary infection of offspring to evaluate lung pathology following RSV reinfection in mice with varying levels of maternal antibody (matAb). Additionally, we aimed to investigate the potential causes of exacerbated lung inflammation in offspring with high matAb levels following secondary RSV exposure. Our findings revealed that offspring with elevated levels of maternal pre-F antibody demonstrated effective protection against lung pathology following the initial RSV infection. However, this protection was compromised upon reinfection, manifesting as heightened weight loss, exacerbated lung pathology, increased expression of RSV-A N genes, eosinophilia, enhanced IL-5, IL-13, MUC5AC, and eosinophils Major Basic Protein (MBP) production in lung tissue compared to offspring lacking matAbs. Importantly, these unexpected outcomes were not attributed to antibody-dependent enhancement (ADE) resulting from declining matAb levels over time. Notably, our findings showed a decline in secretory IgA (sIgA), mucosal IgA, and mucosal IgG levels in offspring with high matAb levels post-primary RSV challenge. We propose that this decline may be a critical factor contributing to the ineffective protection observed during secondary RSV exposure. Overall, these findings offer valuable insights into maternal vaccination against RSV, contributing to a comprehensive understanding and mitigation of potential risks associated with maternal RSV vaccination.

In vitro enhancement of Zika virus infection by preexisting West Nile virus antibodies in human plasma-derived immunoglobulins revealed after P2 binding site-specific enrichment.

Human immunoglobulin preparations contain a diverse range of polyclonal antibodies that reflect past immune responses against pathogens encountered by the blood donor population. In this study, we examined a panel of intravenous immunoglobulins (IGIVs) manufactured over the past two decades (1998-2020) for their capacity to neutralize or enhance Zika virus (ZIKV) infection in vitro. These IGIVs were selected specifically based on their production dates in relation to the occurrences of two flavivirus outbreaks in the U.S.: the West Nile virus (WNV) outbreak in 1999 and the ZIKV outbreak in 2015. As demonstrated by enzyme-linked immunosorbent assay (ELISA) experiments, IGIVs made before the ZIKV outbreak already harbored antibodies that bind to various peptides across the envelope protein of ZIKV because of the WNV outbreak. Using phage display, the most dominant binding site was mapped precisely to the P2 peptide between residues 211 and 230 within domain II, where BF1176-56, an anti-ZIKV monoclonal antibody, also binds. When tested in permissive Vero E6 cells for ZIKV neutralization, the IGIVs, even after undergoing rigorous enrichment for P2 binding specificity, failed, as did BF1176-56. Meanwhile, BF1176-56 enhanced ZIKV infection in both FcγRII-expressing K562 cells and human peripheral blood mononuclear cells. However, for enhancement by the IGIVs to be detected in these cells, a substantial increase in their P2 binding specificity was required, thus linking the P2 site with ZIKV enhancement in vitro. Our findings warrant further study of the significance of elevated levels of anti-WNV antibodies in IGIVs, considering that various mechanisms operating in vivo may modulate ZIKV infection outcomes.IMPORTANCEWe investigated the capacity of intravenous immunoglobulins manufactured previously over two decades (1998-2020) to neutralize or enhance Zika virus infection in vitro. West Nile virus antibodies in IGIVs could not neutralize Zika virus initially; however, once the IGIVs were concentrated further, they enhanced its infection. These findings lay the groundwork for exploring how preexisting WNV antibodies in IGIVs could impact Zika infection, both in vitro and in vivo. Our observations are historically significant, since we tested a panel of IGIV lots that were carefully selected based on their production dates which covered two major flavivirus outbreaks in the U.S.: the WNV outbreak in 1999 and the ZIKV outbreak in 2015. These findings will facilitate our understanding of the interplay among closely related viral pathogens, particularly from a historical perspective regarding large blood donor populations. They should remain relevant for future outbreaks of emerging flaviviruses that may potentially affect vulnerable populations.

Role of Maternal Antibodies in the Protection of Broiler Chicks against Campylobacter Colonization in the First Weeks of Life.

Thermophilic Campylobacter species are the most common cause of bacterium-mediated diarrheal disease in humans globally. Poultry is considered the most important reservoir of human campylobacteriosis, but so far, no effective countermeasures are in place to prevent the bacterium from colonizing broiler flocks. This study investigated maternal antibodies' potential to offer protection against Campylobacter in broiler chicks via a field trial and an immunization trial. In the field trial, breeder flocks with high and low anti-Campylobacter antibody levels in the yolk were selected based on serological screening. Offspring were subsequently monitored for maternal antibodies and Campylobacter prevalence during early life. Although maternal antibodies declined rapidly in the serum of broilers, offspring from flocks with lower anti-Campylobacter antibody levels seemed to be more susceptible to colonization. In the immunization trial, breeders from a seropositive breeder flock were vaccinated with an experimental bacterin or subunit vaccine. Immunization increased antibody levels in the yolk and consequently in the offspring. Elevated maternal antibody levels were significantly associated with reduced Campylobacter susceptibility in broilers at 2 weeks old but not at 1 and 3 weeks old. Overall, the protective effect of maternal immunity should be cautiously considered in the context of Campylobacter control in broilers. Immunization of breeders may enhance resistance but is not a comprehensive solution.

Antiphospholipid Patients Admitted in the Intensive Care Unit: What Must The Rheumatologist Know?

Antiphospholipid syndrome (APS) is a rare systemic autoimmune disorder that can escalate into a 'thrombotic storm' called the catastrophic antiphospholipid syndrome (CAPS), frequently requiring ICU admission for multiple organ failure. This review aims to offer insight and recent evidence on critically-ill APS patients. The CAPS classification criteria define this condition as the involvement of at least three organs/systems/tissues within less than a week, caused by small vessel thrombosis, in patients with elevated antiphospholipid antibodies levels. These criteria do not encompass the full spectrum of critically-ill thrombotic APS patients and they need to be cautiously used for the bedside diagnosis of CAPS. Thrombocytopenia is the laboratory hallmark of CAPS, sometimes dropping below 20G/L, but a complete thrombotic microangiopathy pattern is infrequent. Anticoagulation is the pivotal treatment for APS and CAPS, associated with improved outcome. Triple therapy - the combination of anticoagulation, high-dose corticosteroids, and either plasma exchange or intravenous immunoglobulins - remains the standard treatment for CAPS patients. Eculizumab, an anti-C5 monoclonal antibody, may be useful in refractory patients. Despite significant progress, CAPS mortality rate remains high. Its diagnosis and management are complex, requiring a close multidisciplinary cross talk between APS specialists and intensivists.

Elevated levels of anti-Golgi antibodies: An early sign of seronegative rheumatoid arthritis.

Anti-Golgi antibodies are uncommon antibodies that exhibit specific, polarized cytoplasmic staining on the Hep-2 substrate. The objective of our study was to identify the clinical and laboratory features associated with anti-Golgi antibodies. We examined 4.5 years of data from a Turkish tertiary hospital in this retrospective cohort analysis. The indirect immunofluorescence staining patterns, antinuclear antibody (ANA) titres and clinical data of all patients were obtained from the hospital record system. A total of 146,055 ANAs were detected, of which 224 patients (0.15%) exhibited anti-Golgi antibody staining. In total, 39.4% of diagnosed patients had autoimmune diseases (AIDs). Of the AIDs, 26 (46.4%) were rheumatoid arthritis (RA). This is a very high rate and another remarkable point is that 17 (65.3%) of these patients had seronegative RA. High-titre results (1 ≥ 1/320) were more common in patients with AID. Anti-Ro52 was prevalent in 50% of extractable nuclear antigen (ENA)-positive patients, making it a remarkable finding. The majority of individuals with high-titre anti-Golgi antibodies had AID, particularly RA. The majority of these patients also tested negative for anti-cyclic citrullinated peptide (anti-CCP) and rheumatoid factor (RF). Finally, high-titre anti-Golgi antibodies may be an important serologic marker for seronegative RA in the Turkish population.

Elevated herpesvirus antibody levels linked to schizophrenia and bipolar disorder

IntroductionPrevious research has implicated herpes simplex virus 1 (HSV1) and cytomegalovirus (CMV) in severe mental illness (SMI) with conflicting results. Both pathogens have high universal seroprevalence, are neurotropic and after the primary infection typically establish a persistent latent infection with periodic reactivations. Increased immunoglobin G (IgG) concentrations are considered to be attributable to an increased infection severity with more frequent reactivations or host immune system alterations.ObjectivesWe assessed the HSV1 and CMV IgG concentrations in previously infected (seropositive) patients with SMI and healthy controls (HC). We hypothesized that seropositive patients would show higher IgG concentrations than seropositive HC.MethodsWe included 765 patients, 515 with schizophrenia (SZ) and 250 with bipolar disorder (BP), and 541 HC. HSV1 and CMV IgG seropositivity and concentrations were measured with immunoassays. 355 patients, mean age 33 years, 45% females, and 238 HC, mean age 35 years, 44% females, were HSV1 seropositive (HSV1+) while 447 patients, mean age 33 years, 50% females, and 296 HC, mean age 34 years, 47% females, were CMV seropositive (CMV+). In our main analysis among seropositive participants, we investigated the main effect of patient/control status on HSV1 and CMV IgG concentrations.ResultsThere were no significant differences in CMV or HSV1 seropositivity frequencies between patients with SZ, patients with BP and HC. Among seropositive participants, patients had higher HSV1 (p&lt;0.001) and CMV (p=0.018) IgG concentrations than HC; stratifying by diagnosis, both patients with SZ (p=0.001) and patients with BP (p=0.001) had higher HSV1 IgG concentrations than HC, while patients with SZ, but not BP, had higher CMV (p=0.045) IgG concentrations than HC (Image). For HSV1, higher IgG concentrations were associated with higher general (p=0.017), negative (p=0.041) and positive (p=0.028) psychotic symptom scores.Image:ConclusionsSeropositive patients with SMI showed higher HSV1 and CMV IgG concentrations than seropositive HC suggesting that patients suffer a more severe infection or exhibit an altered immune response when contracting the pathogens. For HSV1, higher IgG concentrations were linked to more psychotic symptoms.Disclosure of InterestD. Andreou: None Declared, N. E. Steen: None Declared, K. N. Jørgensen: None Declared, T. Ueland: None Declared, L. Wortinger: None Declared, L. Mørch-Johnsen: None Declared, R. Yolken: None Declared, O. Andreassen Consultant of: Consultant to HealthLytix, Speakers bureau of: Received speaker’s honorarium from Lundbeck and Sunovion, I. Agartz Speakers bureau of: Received speaker’s honorarium from Lundbeck

Field testing of recombinant subunit vaccines against Teladorsagia circumcincta in lambing ewes demonstrates a lack of efficacy in the face of a multi-species parasite challenge

IntroductionWe previously demonstrated efficacy of an 8-antigen recombinant subunit vaccine against a single species homologous Teladorsagia circumcincta challenge in lambs and in lambing ewes in pen trials. We subsequently demonstrated efficacy of a simplified, 2-antigen, version of this vaccine in lambs in pen trials. Here, we test both vaccines in lambing ewes in a field setting.MethodsIn the work presented here, 12 adjacent plots were seeded with a mixed infection of several common species of parasitic nematodes of sheep in temperate regions, including T. circumcincta. Ewes (n = 144), in groups of 12, grazed for 2 years on these plots and, in the first year, six of these groups of ewes were vaccinated with a 2-antigen prototype vaccine against T. circumcincta prior to mating and then again prior to lambing. In the following year these ewes were immunised again, this time with the 8-antigen prototype vaccine against T. circumcincta prior to mating and then prior to lambing. Throughout both seasons antigen-specific serum antibody levels in ewes and faecal worm egg counts (FEC) in ewes and their lambs were monitored, along with nematode species diversity at lambing.ResultsImmunised ewes produced elevated serum antibody levels to each of the vaccine antigens following immunisation but their FEC levels were not statistically significantly impacted by vaccination with either vaccine. FEC levels were also not impacted in lambs co-grazing the pastures with these immunised ewes. Nematode species diversity was not significantly impacted by vaccination in either year.DiscussionThe immunosuppressive effects of co-infecting gastrointestinal nematodes, the absence of vaccine cross-protection against co-infecting species and the influence of the periparturient relaxation in immunity probably all contributed to the inability of either vaccine to protect against T. circumcincta infection in field trials in the work presented here.

Abstract 6746: A B-cell targeted TLR9 agonist antibody conjugate potentiates cancer vaccine efficacy and rejuvenates vaccine responses in the elderly

Abstract TLR9 agonists (unmethylated CpG oligodeoxynucleotides) are clinically validated as vaccine adjuvants and cancer therapeutics1,2. We developed a Toll-like Receptor Agonist Antibody Conjugate (TRAAC) comprised of a potent TLR9 agonist (T-CpG) conjugated to an antibody against CD22, a receptor restricted to B cells (TAC-001). Systemically administered TAC-001 delivers T-CpG to B cells, resulting in TLR9 activation, and innate and adaptive anti-tumor immunity3. TAC-001 is being evaluated as an immunotherapy in a Phase 1 clinical trial in patients with advanced solid tumors (NCT05399654)4. In this study, we investigated whether TAC-001 mouse surrogate, mCD22 TRAAC, can potentiate cancer vaccine efficacy using preclinical vaccination models. Human Nectin-4 ectodomain protein (N4, 94% homology to its mouse ortholog) was used as a neoantigen-like vaccine, alone and in combination with mCD22 TRAAC, MPLA (a TLR4 agonist), or unconjugated T-CpG. Mice were immunized, then challenged 2 months later with syngeneic CT26 tumors expressing N4. Mice in treatment combination cohorts that resisted tumor development were split into two groups and rechallenged 3.5 months later with a more aggressive tumor, syngeneic 4T1 or 4T1 expressing N4. The combination of vaccine with mCD22 TRAAC was the only treatment able to inhibit growth of the 4T1-N4 tumor. No efficacy was observed in mice inoculated with parental 4T1, thereby demonstrating neoantigen vaccine specific anti-tumor immunity. An MHCI restricted peptide of HER2/neu, GP2, fused to a B cell epitope peptide, P4, and conjugated to KLH, was used as another vaccine model5. GP2-P4-KLH was administered to mice alone or in combination with mCD22 TRAAC or unconjugated T-CpG. Ex vivo GP2/GP2-P4 stimulation of lymphoid organ immune cells from mice treated with vaccine plus mCD22 TRAAC resulted in elevated Granzyme B, IFNγ and IL17A levels, indicating that mCD22 TRAAC enhances T cell activation and cytotoxic activity. Lastly, to investigate the effect of mCD22 TRAAC in elderly mice, SARS-CoV-2 spike protein was used as a vaccine. Spike was administered alone or in combination with mCD22 TRAAC, MPLA or T-CpG. Combining mCD22 TRAAC with vaccine resulted in high levels of spike neutralizing IgG in both youth and elderly cohorts, showing that mCD22 TRAAC rejuvenates vaccine responses in elderly. In all studies, mCD22 TRAAC led to the most potent vaccine recall response, with high antigen specific IgG titers skewing towards a Th1 phenotype, as shown by elevated levels of effector function antibodies of IgG2a subclass and increased IFNγ production. These findings provide a strong rationale for combining TAC-001 with cancer vaccines. References1Hyer et al., Vaccine 2018; 36(19) 2Long et al., Annals of Oncology 2018; 29(8) 3Kuo et al., Cancer Research 2021; 81(13)4Perez et al., JITC 2023; 11(1) 5Nordin et al., Cancers 2021; 13(19) Citation Format: Maja Z. Bonacorsi, Amy Chen, Ons Harrabi, Min Li, Emma R. Sangalang, Danielle Fontaine, Janet Sim, Pavel Strop, Hong I. Wan, Maria Jose Costa. A B-cell targeted TLR9 agonist antibody conjugate potentiates cancer vaccine efficacy and rejuvenates vaccine responses in the elderly [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6746.

Amikacin Liposome Inhalation Suspension in the Real-World Management of Refractory Mycobacterium avium Complex Pulmonary Disease.

The increasing prevalence of Mycobacterium avium complex (MAC) pulmonary disease poses a significant therapeutic challenge, particularly due to the limited efficacy and systemic toxicity associated with conventional guideline-based therapy. Amikacin liposome inhalation suspension (ALIS) has been developed, yet its real-world application remains underreported. This retrospective analysis, conducted from March 2021 to February 2024, examined ALIS's clinical use in patients aged 20 years or older with refractory MAC pulmonary disease at our institution. The primary objective of this study is to describe the patient characteristics and clinical trajectories associated with the initiation of ALIS therapy in real-world settings for individuals diagnosed with MAC pulmonary disease. Of 11 patients initiated on ALIS, one was excluded due to financial constraints impacting continuation. The analysis proceeded with the remaining 10 subjects. The mean age of participants was 70.2 years, with a predominance of female patients (n = 7, 70%) and a higher incidence of M. avium infections (n = 6, 60%). Forty percent of the cohort (n = 4) had a history of ethambutol-induced optic neuritis leading to the cessation of the drug. The average interval from the initiation of guideline-based therapy to the start of ALIS was 8.5 ± 6.9 years (mean ± standard deviation). The majority (80%) presented with positive Gaffky scores at ALIS initiation, and a significant proportion exhibited resistance to clarithromycin and ethambutol. Comorbid conditions, including diabetes and previous cancer, were noted. The study also observed elevated anti-MAC antibody levels. Treatment duration varied, with fatigue leading to discontinuation in two cases. Treatment-emergent adverse events were documented in individual patients, each presenting with grade 1 severity: hemoptysis (n = 1, 10%), elevated creatinine levels (n = 1, 10%), and dysphonia (n = 2, 20%) were observed, respectively. Correlation analysis revealed a significant inverse relationship between body mass index (BMI) and ALIS discontinuation due to fatigue, and a positive correlation between Gaffky scores and C-reactive protein (CRP) levels. These results underscore the potential benefits and limitations of ALIS, suggesting that timely intervention and comprehensive healthcare support are crucial for optimal outcomes in the treatment of advanced MAC pulmonary disease.

Discovering peptides and computational investigations of a multiepitope vaccine target Mycobacterium tuberculosis

Mycobacterium tuberculosis (MTB) is the causative agent of tuberculosis (TB), a prevalent airborne infectious disease. Despite the availability of the Bacille Calmette-Guerin vaccine, its global efficacy remains modest, and tuberculosis persists as a significant global public health threat. Addressing this challenge and advancing towards the End MTB Strategy, we developed a multiepitope vaccine (MEV) based on immunoinformatics and computational approaches. Immunoinformatics screening of MBT protein identified immune-dominant epitopes based on Major Histocompatibility Complex (MHC) allele binding, immunogenicity, antigenicity, allergenicity, toxicity, and cytokine inducibility. Selected epitopes were integrated into an MEV construct with adjuvant and linkers, forming a fully immunogenic vaccine candidate. Comprehensive analyses encompassed the evaluation of immunological and physicochemical properties, determination of tertiary structure, molecular docking with Toll-Like Receptors (TLR), molecular dynamics (MD) simulations for all atoms, and immune simulations. Our MEV comprises 534 amino acids, featuring 6 cytotoxic T lymphocyte, 8 helper T lymphocyte, and 7 linear B lymphocyte epitopes, demonstrating high antigenicity and stability. Notably, molecular docking studies and triplicate MD simulations revealed enhanced interactions and stability of MEV with the TLR4 complex compared to TLR2. In addition, the immune simulation indicated the capacity to effectively induce elevated levels of antibodies and cytokines, emphasizing the vaccine's robust immunogenic response. This study presents a promising MEV against TB, exhibiting favorable immunological and physicochemical attributes. The findings provide theoretical support for TB vaccine development. Our study aligns with the global initiative of the End MTB Strategy, emphasizing its potential impact on addressing persistent challenges in TB control.

Antibody level comparison after porcine epidemic diarrhea vaccination via different immunization routes.

Porcine epidemic diarrhea (PED) is a disease extremely harmful to pig health. Intramuscular and Houhai acupoint injections are the main immunization routes to prevent and control PED. This study aimed to evaluate the efficacy of these two routes in pregnant sows based on serum IgG, IgA, and neutralizing antibody levels. PED virus (PEDV) immunoprophylaxis with live-attenuated and inactivated vaccines was administered. The vaccinations for the intramuscular injections elevated IgG and neutralizing antibody levels more than Houhai acupoint injections at most timepoints after immunization. However, the anti-PEDV IgA antibodies induced by vaccination with the two immunization routes did not differ significantly. In conclusion, intramuscular injections are better than Houhai acupoint injections for PEDV vaccination of pregnant sows.

Free PEG Suppresses Anaphylaxis to PEGylated Nanomedicine in Swine.

Covalent conjugation of poly(ethylene glycol) (PEG) is frequently employed to enhance the pharmacokinetics and biodistribution of various protein and nanoparticle therapeutics. Unfortunately, some PEGylated drugs can induce elevated levels of antibodies that can bind PEG, i.e., anti-PEG antibodies (APA), in some patients. APA in turn can reduce the efficacy and increase the risks of allergic reactions, including anaphylaxis. There is currently no intervention available in the clinic that specifically mitigates allergic reactions to PEGylated drugs without the use of broad immunosuppression. We previously showed that infusion of high molecular weight free PEG could safely and effectively suppress the induction of APA in mice and restore prolonged circulation of various PEGylated therapeutics. Here, we explored the effectiveness of free PEG as a prophylaxis against anaphylaxis induced by PEG-specific allergic reactions in swine. Injection of PEG-liposomes (PL) resulted in anaphylactoid shock (pseudoanaphylaxis) within 1-3 min in both naïve and PL-sensitized swine. In contrast, repeated injection of free PEG alone did not result in allergic reactions, and injection of free PEG effectively suppressed allergic reactions to PL, including in previously PL-sensitized swine. These results strongly support the further investigation of free PEG for reducing APA and allergic responses to PEGylated therapeutics.