Delayed-type Hypersensitivity Reaction Research Articles

Tanshinone I inhibits the functions of T lymphocytes and exerts therapeutic effects on delayed-type hypersensitivity reaction via blocking STATs signaling pathways

Delayed-type hypersensitivity (DTH) reactions are a kind of chronic inflammatory diseases initiated by antigens and antigen-specific T cells. Currently, the therapy of DTH reactions is limited by the poor curative effects and serious adverse reactions of existing agents. In this study, we investigated the regulatory effects of tanshinone Ⅰ, a natural compound isolated from Salvia miltiorrhiza, on the functions of multiple immune cells and its therapeutic effects on DNFB-induced DTH reaction, and then explored its immunosuppressive mechanisms. The results showed that tanshinone Ⅰ at 5 to 20 μM moderately inhibited the activation of macrophages and dendritic cells, but did not weaken the activation of neutrophils. Tanshinone Ⅰ at 1 to 4 μM intensively suppressed the activation, proliferation, and differentiation of CD4+ and CD8+ T cells, and slightly affected the functions of B cells. Tanshinone Ⅰ administration markedly alleviated the edema, inflammatory response, and the infiltrations of CD4+ T cells, CD8+ T cells, and CD11b+ cells in ear tissues of mice which were induced DTH reactions by DNFB. Transcriptome analysis revealed that tanshinone Ⅰ strongly inhibited CD4+ T cells to express genes involving in cell proliferation, metabolism, activation, and differentiation. Furthermore, immunoblotting analysis showed that tanshinone Ⅰ selectively inhibited the phosphorylation of STAT3 and STAT5 in CD4+ T cells stimulated by anti-CD3e and anti-CD28 antibodies or IL-2. Collectively, tanshinone Ⅰ can strongly inhibit the functions of T lymphocytes, exert therapeutic effects on DTH reaction by blocking STATs signaling pathways, and has potential to be developed into therapeutic drug for DTH reactions.

In vitro diagnostics of drug allergies.

In vitro diagnostics for drug hypersensitivity reactions distinguish between serological and cellular-based tests. A serological test used for the diagnosis of immediate type reactions is the detection of specific IgE antibodies. The cellular tests include the basophil activation test for immediate type reactions and the lymphocyte transformation test, which is mainly used to detect delayed type hypersensitivity reactions. Further cellular-based tests are the CAST-ELISA and the mast cell activation test. None of the above-mentioned tests can definitively exclude an allergy if the result is negative. In addition, it is important to note that even a positive test result is not necessarily associated with an allergy but has to be interpreted in the clinical context.

Immunomodulatory properties of splenocytes treated with chlorpromazine in experimental aggression

Aggressive behavior is considered to be as one of the central symptoms of many neuropsychiatric disorders. It is a serious medical and biological problem associated both with high frequency and severity of manifestations and lack of selective correction means. The purpose of this study was to evaluate the functional phenotype of immune cells treated with chlorpromazine in aggressive animals in vitro, as well as the effect of transplantation of these cells on syngeneic aggressive recipient’s immune cells functional activity. Aggressive behavior was formed in active mice as a result of repeated experience of victories in agonistic interactions with animals with a submissive partner. Further, aggressive animals were isolated into individual cells and used as donors and recipients of immune cells. Immune cells were obtained under sterile conditions from suspension of spleen cells precultured with chlorpromazine. The level of spontaneous and mitogen-induced cell proliferation was assessed using a standard method of radioactive label incorporation. The quantitative content of cytokines in samples of treated with chlorpromazine cell cultures supernatant was determined by enzyme immunoassay using appropriate test systems. Further aggressive syngeneic recipients were intravenously injected with splenocytes precultured with chlorpromazine. The control group of animals was injected with splenocytes precultured under similar conditions, without the chlorpromazine addition. The recipients were assessed for the spleen cells proliferative activity and the intensity of humoral and cellular immune response using standard methods, by the number of antibody-forming spleen cells and severity of a delayed-type hypersensitivity reaction in response to T-dependent antigen introduction. It was found that treatment with chlorpromazine in vitro suppressed mitogen-stimulated proliferation of splenocytes in aggressive mice, without changing of spontaneous proliferation. It was also accompanied by some cytokines production decrease: IL-6, IL-2 and IFNã. When studying the humoral and cellular immune response intensity in aggressive recipients after transplantation of donor’s syngeneic splenocytes treated with chlorpromazine, a decrease in the intensity of humoral immune response was recorded. Transplantation of donor’s splenocytes treated with chlorpromazine was also accompanied by a decrease in spontaneous and mitogen-stimulated proliferation of splenocytes from aggressive recipients. Thus, the obtained data indicate the inhibitory effect of chlorpromazine on immune cell’s functional activity in aggressive mice, as well as the positive immunomodulatory effect of chlorpromazine-treated immune cells transplantation at aggressive behavior in experimental animals.

Allergic contact dermatitis in the beauty industry

Allergic contact dermatitis in the beauty industry is a common and growing problem in dermatology, due to both the annual increase in the popularity of existing beauty services and the emergence of new fashion trends. Cosmetic products in hairdressing, manicure, permanent makeup, eyelash extensions, tattooing and piercing contain a number of potent haptens, sensitization to which results in a classic delayed-type hypersensitivity reaction. The development of contact allergic reactions is important not only for consumers of these services, but also for hairdressers and beauty salon technicians themselves. Thus, hairdressers take first place in the incidence statistics of occupational contact dermatitis associated with allergens and haptens in hair dyes, products for bleaching, curling or straightening hair. In 65% of cases, allergic contact dermatitis to acrylates develops among manicurists within the first years of work. The basis of treatment for allergic contact dermatitis is external therapy using topical glucocorticosteroids. The article contains Russian and foreign literature data about the most common allergens in products used in hairdressing, permanent tattooing, eyelash extensions, manicure and piercing, on the prevalence and characteristics of allergic contact dermatitis in these areas of the beauty industry and our own clinical observations of the effectiveness of treatment of allergic contact dermatitis using Comfoderm K cream (methylprednisolone aceponate with ceramides in the base).

Drug fever-an immune-mediated delayed type hypersensitivity reaction to Vinca alkaloids in pediatric oncology patients, possibly mediated by cysteinyl leukotrienes.

Drug hypersensitivity reactions are common in pediatric hemato-oncology patients due to multiple factors including immune compromise and pharmacological complexities. Fever can signify severe delayed-type hypersensitivity reactions such as drug reaction with eosinophilia and systemic symptoms (DRESS) or drug-induced hypersensitivity syndrome (DIHS). The etiology of fever as an isolated hypersensitivity reaction to chemotherapeutic agents not fully understood. Here, we report three children with intracranial neoplasms experiencing recurrent febrile reactions following Vinca alkaloid-based chemotherapy, mitigated by cysteinyl leukotriene receptor antagonist therapy. We present a series of pediatric patients with diverse intracranial neoplasms who developed recurrent fever episodes after multiple courses of Vinca alkaloid-based chemotherapy. Treatment involved prophylactic and post-chemotherapy administration of a cysteinyl leukotriene receptor antagonist to prevent fever episodes and enable completion of chemotherapy regimens without protocol modifications or desensitization. All three patients experienced fever consistent with delayed-type hypersensitivity reactions to Vinca alkaloids. Prophylactic use of the leukotriene antagonist Montelukast successfully prevented fever recurrence, allowing uninterrupted completion of chemotherapy courses. Our findings suggest that Montelukast, a leukotriene antagonist, may be beneficial in managing fever as a delayed-type hypersensitivity reaction to Vinca alkaloids in pediatric patients. Further research is warranted to elucidate the underlying mechanisms and leukotriene pathways involved in drug-induced fever reactions.

Experimentally investigated “CoronaDerm-PS”-driven SARS-CoV-2-specific cellular immunity and safety

Novel coronavirus disease 2019, caused by the SARS-CoV-2, initiate humoral and cellular immune responses against diverse virus antigens. The assessment of SARS-CoV-2-specific is mainly carried out in routine practice by determining specific immunoglobulins. However, high variability in S-protein structure in new genovariants of SARS-CoV-2 virus and the lack of correlation between specific antibodies and CD8+ T-lymphocytes underlie false negative responses, and mass assessment of cellular immunity is complicated due to the complexity of applying ELISPOT and cytofluorometry techniques. To solve this issue, a diagnostic method was developed for assessing SARS-CoV-2-specific cellular immune response, which is based on a skin test followed by evaluating a delayed-type hypersensitivity reaction involving antigen-specific memory T-lymphocytes. A diagnostic preparation CoronaDerm-PS is based on Cord_PS, which is a hybrid recombinant protein consisting of parts of the SARS-CoV-2 structural proteins S, M, N, E. The specific activity of this chimeric antigen was analyzed in cultured T-lymphocyte activation test by assessing interferon-γ production using cytofluorometry. To investigate the chimeric antigen specific activity, a preclinical safety study with CoronaDerm-PS preparation in experimental animals was conducted. A dose-dependent developing skin reaction was observed in 90–100% of guinea pigs vaccinated by EpiVacCorona, CoviVac, Gam-COVID-Vac, which confirms a potential for assessing post-vaccination cellular immunity using CoronaDerm-PS preparation. Upon this, the presence of functionally active T-cell-antigenic epitopes in the recombinant polypeptide allows to evaluate SARS-CoV-2-specific response illustrated by detected response after Gam-COVID-Vac (S-protein) and EpiVacCorona (N-protein) vaccination. Thus, a skin test based on CoronaDerm-PS preparation may be a promising diagnostic tool for rapid mass screening requiring no specialized laboratory equipment for assessing populational SARS-CoV-2-specific immunity. Such a test is distinguished by advantages such as ease of analysis, high specificity and sensitivity. The final decision-making on using this test in a real-world practice may achieved after conducting further clinical safety and effectiveness trials.

Systemic and skin-limited delayed-type drug hypersensitivity reactions associate with distinct resident and recruited T cell subsets.

Delayed-type drug hypersensitivity reactions are major causes of morbidity and mortality. The origin, phenotype, and function of pathogenic T cells across the spectrum of severity require investigation. We leveraged recent technical advancements to study skin-resident memory T cells (TRMs) versus recruited T cell subsets in the pathogenesis of severe systemic forms of disease, Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) and drug reaction with eosinophilia and systemic symptoms (DRESS), and skin-limited disease, morbilliform drug eruption (MDE). Microscopy, bulk transcriptional profiling, and single-cell RNA-sequencing (scRNA-Seq) plus cellular indexing of transcriptomes and epitopes by sequencing (CITE-Seq) plus T cell receptor sequencing (TCR-Seq) supported clonal expansion and recruitment of cytotoxic CD8+ T cells from circulation into skin along with expanded and nonexpanded cytotoxic CD8+ skin TRM in SJS/TEN. Comparatively, MDE displayed a cytotoxic T cell profile in skin without appreciable expansion and recruitment of cytotoxic CD8+ T cells from circulation, implicating TRMs as potential protagonists in skin-limited disease. Mechanistic interrogation in patients unable to recruit T cells from circulation into skin and in a parallel mouse model supported that skin TRMs were sufficient to mediate MDE. Concomitantly, SJS/TEN displayed a reduced Treg signature compared with MDE. DRESS demonstrated recruitment of cytotoxic CD8+ T cells into skin as in SJS/TEN, yet a pro-Treg signature as in MDE. These findings have important implications for fundamental skin immunology and clinical care.

A phase I trial of vaccination with lethally irradiated lymphoma cells admixed with granulocyte-macrophage colony-stimulating factor secreting K562 cells for the treatment of follicular lymphoma

Several vaccine strategies have been tested for the treatment of follicular lymphoma; however, none have proven successful. In a phase I dose-escalation protocol, we developed a vaccine consisting of lethally irradiated whole lymphoma cells admixed with K562 cells that constitutively secreted granulocyte-macrophage colony-stimulating factor (GM-K562)(ClinicalTrials.gov identifier: NCT00487305). Patients with grade 1, 2, or 3 A follicular lymphoma were divided into 2 study tiers based on prior treatment and received a maximum of 6 vaccines. Vaccines contained dose levels of 5 × 106 or 1 × 107 GM-K562 cells admixed with autologous tumor cells at doses ranging from 1 × 105 to 5 × 107.Correlative studies did not demonstrate a significant immune response as assessed by delayed-type hypersensitivity reactions, B and T cell subsets, and natural killer cell subsets. Future vaccine studies should focus on identifying lymphoma-specific immunogenic proteins and modifying the vaccine immune adjuvant.

Anti-inflammatory Property of Ethanolic Extract of Cleome spinosa Leaves in an in vivo Model of Delayed-type Hypersensitivity

Objectives Delayed-type hypersensitivity (DTH) reactions represent a clinically important class of immune responses that have wide-ranging implications in various health and disease conditions. The existing anti-inflammatory drugs to treat DTH have several shortcomings including severe side-effects. Thus, a new plant-derived anti-inflammatory drug with no or less toxicity would be effective in treating DTH. The Cleome genus has been routinely used to cure various ailments including inflammation. This study investigates the anti-inflammatory properties of the ethanolic leaf extract of Cleome spinosa (CSE) in a DTH model for the first time. Materials and Methods DTH response was induced by 2, 4-di nitro-fluorobenzene in the mouse foot pad. Histological sectioning of the paw was carried out to find changes in the architecture of the tissue. Serum tumour necrosis factor-alpha (TNF-α) was estimated through enzyme linked immunosorbent assay (ELISA), and the bioactive compounds present in CSE were analysed through reversed phase-high-performance liquid chromatography. Results With CSE treatment, the oedema in the resensitized paw alleviated faster with no loss of digits compared to the controls. Histological study of the resensitized paw showed less dermal and sub-dermal thickening and less collagen deposition that regained normal tissue architecture during the healing process with CSE treatment. CSE treatment did not show any adverse haematological and histopathological changes in the visceral organs of mice. The level of serum TNF-α was found to be significantly lower with CSE treatment. CSE was found to be rich in phenol, flavonoids, tocopherol, carotene and phytosteroids. Conclusion The anti-inflammatory and immunomodulatory role of CSE against hapten-induced deleterious DTH inflammation suggests its therapeutic potential in treating inflammatory diseases and combating infections.

Study on the material basis and immunological enhancement activity of dangdi oral liquid

Studies have shown that a lot of traditional Chinese medicines could improve the immunity of the body. Dangdi oral liquid (DDO) was mainly composed of Angelica sinensis (Oliv.) Diels (Danggui), Rehmannia glutinosa Libosch. (Dihuang), Achyranthes bidentata Bl. (Niuxi), Glycyrrhiza uralensis Fisch. (Gancao). In this study, the rapid ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) method was used to identify the potentially effective compounds of DDO. Then the immune activity of DDO was measured by lymphocyte proliferation, macrophage phagocytic function, NK cell activity, delayed type hypersensitivity reaction, hemolytic plaque number, sIgA content and immune organ index. The results showed that a total of 51 compounds were identified. In addition, DDO could significantly promote the lymphocyte proliferation, improve macrophage phagocytic ability, NK cell activity, hemolytic plaque number, sIgA content and immune organ index compared with control group, and the medium dose possessed the best efficacy (P＜0.05). These results indicated that DDO could enhance the immunity of mice.

Yogurt Alleviates Cyclophosphamide-Induced Immunosuppression in Mice through D-Lactate.

Numerous studies have investigated the immunomodulatory effects of yogurt, but the underlying mechanism remained elusive. This study aimed to elucidate the alleviating properties of yogurt on immunosuppression and proposed the underlying mechanism was related to the metabolite D-lactate. In the healthy mice, we validated the safety of daily yogurt consumption (600 μL) or D-lactate (300 mg/kg). In immunosuppressed mice induced by cyclophosphamide (CTX), we evaluated the immune regulation of yogurt and D-lactate. The result showed that yogurt restored body weight, boosted immune organ index, repaired splenic tissue, recovered the severity of delayed-type hypersensitivity reactions and increased serum cytokines (IgA, IgG, IL-6, IFN-γ). Additionally, yogurt enhanced intestinal immune function by restoring the intestinal barrier and upregulating the abundance of Bifidobacterium and Lactobacillus. Further studies showed that D-lactate alleviated immunosuppression in mice mainly by promoting cellular immunity. D-lactate recovered body weight and organ development, elevated serum cytokines (IgA, IgG, IL-6, IFN-γ), enhanced splenic lymphocyte proliferation and increased the mRNA level of T-bet in splenic lymphocyte to bolster Th1 differentiation. Finally, CTX is a chemotherapeutic drug, thus, the application of yogurt and D-lactate in the tumor-bearing mouse model was initially explored. The results showed that both yogurt (600 μL) and D-lactate (300 mg/kg) reduced cyclophosphamide-induced immunosuppression without promoting tumor growth. Overall, this study evaluated the safety, immune efficacy and applicability of yogurt and D-lactate in regulating immunosuppression. It emphasized the potential of yogurt as a functional food for immune regulation, with D-lactate playing a crucial role in its immunomodulatory effects.

Abstract PO3-05-12: Randomized Phase 2 of Bria-IMT, an Allogenic Human Cell Line with Antigen Presenting Activity, in Heavily Pretreated Metastatic Breast Cancer

Abstract Introduction Despite progress in MBC, too many continue to succumb due to treatment resistance or intolerance. SV-BR-1-GM is an allogenic human breast cancer cell line with antigen presenting cell activity designed to overcome the immune-suppressive tumor microenvironment while being acceptable to extensively pretreated contemporary MBC patients. We report interim exploratory analysis of the ongoing RCT of the Bria-IMT regimens. Methods An interim exploratory analysis using preliminary partially available evaluable data of the ongoing prospective, randomized phase 2 (NCT03328026; 2018-present) of Bria-IMT (irradiated SV-BR-1-GM) with a PD-1check point inhibitor (CPI) every 3 weeks (25 patients dosed to date). Both regimens include cyclophosphamide 300 mg/m2 48-72 hours prior to intradermal Bria-IMT (~20 x 106 cells) followed by interferon-alpha at the inoculation sites 2 days later. The control arm used the original sequence with simultaneous start of Bria-IMT and CPI in cycle 1. The experimental arm started CPI in cycle 2 after the 2nd inoculation. Candida skin test was performed before cycle 1 to determine anergy status while delayed-type hypersensitivity skin test (DTH), defined as >5mm erythema & induration, was done at every cycle by intradermal injection of a small test dose of Bria-IMT prior to full dose inoculation. Results Median age: 58 (range 37-81); median prior therapies: 8 lines (range 4-18); 89% were grade 2/3 (n=18); 68% hormone receptor positive; 61% HER2 negative, 33% HER2 low, and 6% HER2 high; 33% triple negative. Overall, 53% of subjects had a clinical benefit as best response by BICR, PI or target lesion measurement. The two treatment arms were similar with a trend showing longer median durations on therapy (mDOT) of 3.7 mo in the experimental delayed CPI arm compared with mDOT = 2.9 for original sequence control arm. 47% of patients were anergic to candida. Among all anergic subjects, the mDOT was 3.5 compared to 2.5 mo for non-anergic patients. However, among anergic subjects, the alternative treatment arm had a lower risk of treatment discontinuation (improved HR) with mDOT of 3.7 compared to the 3.3 mo mDOT of the original treatment. 50% of anergic subjects eventually developed DTH to SV-BR-1-GM. mDOT was 4.0 mo for DTH+ pts vs 3.0 mo for those who did not mount DTH. Median OS was not yet reached; mean OS was higher in non-anergic vs anergic pts. Among those who developed an inoculation site reaction to Bria-IMT, OS was greater than for those who did not. Time on the Bria-IMT regimen exceeded the time on penultimate treatment in 22% of subjects while 33% of subjects with prior CPI use exceeded last therapy. AEs were mild with 28% of subjects (n=7) having > grade 3 events. The most common grade 3+ AE was lipase increase (n=3). One subject with encouraging changes in peripheral blood tumor markers and CTCs completed a PET study using Zr-89 crefmirlimab berdoxam, a zirconium-89 labelled truncated antibody specific to human CD8α (CD8 Immuno-PET) and demonstrated increased uptake in some metastatic lesions and draining lymph nodes. Updated results will be provided at the meeting. Conclusion Sequencing of CPI with Bria-IMT is associated with differential clinical outcome trends but not statistically significant in this interim preliminary exploratory analysis regardless of prior CPI use. Bria-IMT is immunogenic with clinical benefit demonstrated for both treatment schedules among patients with inducible DTH reactions. Patients who develop an immune response to Bria-IMT had an increase in OS compared to those who did not. The nodal localization of CD8+ cells on PET may indicate a systemic activation of CD8 positive lymphoid cells. It also provides support that the Bria-IMT + CPI combination immune-based therapy can result in an increase of CD8+ tumor infiltrating lymphocytes in breast cancer metastatic sites. These preliminary results will be evaluated in the ongoing randomized phase 3 pivotal registrational trial. Citation Format: Carmen Calfa, Chaitali Nangia, Minal Barve, John Knecht, Jarrod Holmes, Kendrith Roland, Ralph Boccia, Frances Valdes-Albini, Zach Gostout, Mingjin Chang, William Williams, Charles Wiseman, Bonnie Guerin, Shaker Dakhil, Giuseppe Del Priore, Saranya Chumsri. Randomized Phase 2 of Bria-IMT, an Allogenic Human Cell Line with Antigen Presenting Activity, in Heavily Pretreated Metastatic Breast Cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-05-12.

Effect of feeding Moringa oleifera based complete pellet feed on milk yield, composition, fatty acids, somatic cell count and cell mediated immunityin lactating goats

Lactation cum feeding trial was conducted on 12 female Barbari goats (Age approx. 2-3 years and mean body weight 34.72 ±1.28 kg) for 120 days after approximately one month of kidding and effect on milk production, milk constituents, somatic cell count, milk fatty acid profile and cell mediated immunity was studied. Animals were divided into two groups (Gr G and Gr M) of six each as per completely randomized design. Two types of complete pellet (Moringa oleifera and Cicer arietinum) based was formulated containing sundried Moringa biomass and Gram straw along with conventional feed ingredients. Lactating goats of Gr G was fed with gram straw based complete pellet feed while goats of Gr M was fed with Moringa based complete pellet feed. Both the complete pellet feeds were iso nitrogenous. No significant difference in body weight changes was recorded between groups. The milk production (g/day) was higher (Avg. 14.54%) in Gr M as compared to Gr G at different fortnight. No significant difference was reported in the milk composition. Milk fat, SNF, Protein and lactose was similar in both the groups. Milk Somatic cell count (×10 3/ml) was significantly (P<0.05) lower in lactating goats fed with Moringa based feed. Cell-mediated immune response assessed through delayed-type hypersensitivity (DTH) reaction against phyto haemagglutinin (PHA-P) was more pronounced in Gr M at 72 and 96 hrs.Higher concentration of unsaturated fatty acids (about 16.19%) and lower saturated fatty acids (about 5.49%) was reported in Gr M. Milk fatty acid profile indicators like Index of atherogenicity (IA) was lower while hypo/hyper cholesteremic ratio and health promoting index was higher in milk of moringa based pellet fed goats. Present study concluded that Barbari goats fed with Moringa based complete pellet feed produced higher milk yield with healthier fatty acid profile with low somatic cell counts.

Safety and immunogenicity of a polyvalent DNA–protein HIV vaccine with matched Env immunogens delivered as a prime–boost regimen or coadministered in HIV-uninfected adults in the USA (HVTN 124): a phase 1, placebo-controlled, double-blind randomised controlled trial

An effective HIV vaccine will most likely need to have potent immunogenicity and broad cross-subtype coverage. The aim of the HIV Vaccine Trials Network (HVTN) 124 was to evaluate safety and immunogenicity of a unique polyvalent DNA-protein HIV vaccine with matching envelope (Env) immunogens. HVTN 124 was a randomised, phase 1, placebo-controlled, double-blind study, including participants who were HIV seronegative and aged 18-50 years at low risk for infection. The DNA vaccine comprised five plasmids: four copies expressing Env gp120 (clades A, B, C, and AE) and one gag p55 (clade C). The protein vaccine included four DNA vaccine-matched GLA-SE-adjuvanted recombinant gp120 proteins. Participants were enrolled across six clinical sites in the USA and were randomly assigned to placebo or one of two vaccine groups (ie, prime-boost or coadministration) in a 5:1 ratio in part A and a 7:1 ratio in part B. Vaccines were delivered via intramuscular needle injection. The primary outcomes were safety and tolerability, assessed via frequency, severity, and attributability of local and systemic reactogenicity and adverse events, laboratory safety measures, and early discontinuations. Part A evaluated safety. Part B evaluated safety and immunogenicity of two regimens: DNA prime (administered at months 0, 1, and 3) with protein boost (months 6 and 8), and DNA-protein coadministration (months 0, 1, 3, 6, and 8). All randomly assigned participants who received at least one dose were included in the safety analysis. The study is registered with ClinicalTrials.gov (NCT03409276) and is closed to new participants. Between April 19, 2018 and Feb 13, 2019, 60 participants (12 in part A [five men and seven women] and 48 in part B [21 men and 27 women]) were enrolled. All 60 participants received at least one dose, and 14 did not complete follow-up (six of 21 in the prime-boost group and eight of 21 in the coadminstration group). 11 clinical adverse events deemed by investigators as study-related occurred in seven of 48 participants in part B (eight of 21 in the prime-boost group and three of 21 in the coadministration group). Local reactogenicity in the vaccine groups was common, but the frequency and severity of reactogenicity signs or symptoms did not differ between the prime-boost and coadministration groups (eg, 20 [95%] of 21 in the prime-boost group vs 21 [100%] of 21 in the coadministration group had either local pain or tenderness of any severity [p=1·00], and seven [33%] vs nine [43%] had either erythema or induration [p=0·97]), nor did laboratory safety measures. There were no delayed-type hypersensitivity reactions or vasculitis or any severe clinical adverse events related to vaccination. The most frequently reported systemic reactogenicity symptoms in the active vaccine groups were malaise or fatigue (five [50%] of ten in part A and 17 [81%] of 21 in the prime-boost group vs 15 [71%] of 21 in the coadministration group in part B), headache (five [50%] and 18 [86%] vs 12 [57%]), and myalgia (four [40%] and 13 [62%] vs ten [48%]), mostly of mild or moderate severity. Both vaccine regimens were safe, warranting evaluation in larger trials. US National Institutes of Health and US National Institute of Allergy and Infectious Diseases.

Structural characterization and immunostimulant activities of polysaccharides fractionated by gradient ethanol precipitation method from Panax ginseng C. A. Meyer.

Panax ginseng C. A. Meyer is a dual-purpose plant for medicine and food, its polysaccharide is considered as an immune enhancer. Four polysaccharides, WGP-20-F, WGP-40-F, WGP-60-F and WGP-80-F were obtained from ginseng via water extraction and gradient ethanol precipitation with different molecular weights (Mw) of 1.720 × 106, 1.434 × 106, 4.225 × 104 and 1.520 × 104Da, respectively. WGP-20-F and WGP-40-F which with higher Mw and a triple-helix structure are glucans composed of 4-ɑ-Glcp, do not show remarkable immunoregulatory effects. WGP-60-F and WGP-80-F are heteropolysaccharides mainly composed of 4-ɑ-Glcp and also contain t-ɑ-Araf, 5-ɑ-Araf and 3,5-ɑ-Araf. They are spherical branched conformations without a triple-helix structure and can effectively increase the index of immune organs, lymphocyte proliferation, activate macrophages to regulate the immune system in mice and further enhance immune functions by improving delayed-type hypersensitivity reaction and antibody response. These results indicated that WGP-60-F and WGP-80-F could be used as potential immune enhancers, and gradient ethanol precipitation can be applied for the preparation of ginseng bioactive polysaccharide.

Long-Term Survival and Immune Response Dynamics in Melanoma Patients Undergoing TAPCells-Based Vaccination Therapy.

Cancer vaccines present a promising avenue for treating immune checkpoint blockers (ICBs)-refractory patients, fostering immune responses to modulate the tumor microenvironment. We revisit a phase I/II trial using Tumor Antigen-Presenting Cells (TAPCells) (NCT06152367), an autologous antigen-presenting cell vaccine loaded with heat-shocked allogeneic melanoma cell lysates. Initial findings showcased TAPCells inducing lysate-specific delayed-type hypersensitivity (DTH) reactions, correlating with prolonged survival. Here, we extend our analysis over 15 years, categorizing patients into short-term (<36 months) and long-term (≥36 months) survivors, exploring novel associations between clinical outcomes and demographic, genetic, and immunologic parameters. Notably, DTHpos patients exhibit a 53.1% three-year survival compared to 16.1% in DTHneg patients. Extended remissions are observed in long-term survivors, particularly DTHpos/M1cneg patients. Younger age, stage III disease, and moderate immune events also benefit short-term survivors. Immunomarkers like increased C-type lectin domain family 2 member D on CD4+ T cells and elevated interleukin-17A were detected in long-term survivors. In contrast, toll-like receptor-4 D229G polymorphism and reduced CD32 on B cells are associated with reduced survival. TAPCells achieved stable long remissions in 35.2% of patients, especially M1cneg/DTHpos cases. Conclusions: Our study underscores the potential of vaccine-induced immune responses in melanoma, emphasizing the identification of emerging biological markers and clinical parameters for predicting long-term remission.

Current Insights into Tissue Injury of Giant Cell Arteritis: From Acute Inflammatory Responses towards Inappropriate Tissue Remodeling.

Giant cell arteritis (GCA) is an autoimmune disease affecting large vessels in patients over 50 years old. It is an exemplary model of a classic inflammatory disorder with IL-6 playing the leading role. The main comorbidities that may appear acutely or chronically are vascular occlusion leading to blindness and thoracic aorta aneurysm formation, respectively. The tissue inflammatory bulk is expressed as acute or chronic delayed-type hypersensitivity reactions, the latter being apparent by giant cell formation. The activated monocytes/macrophages are associated with pronounced Th1 and Th17 responses. B-cells and neutrophils also participate in the inflammatory lesion. However, the exact order of appearance and mechanistic interactions between cells are hindered by the lack of cellular and molecular information from early disease stages and accurate experimental models. Recently, senescent cells and neutrophil extracellular traps have been described in tissue lesions. These structures can remain in tissues for a prolonged period, potentially favoring inflammatory responses and tissue remodeling. In this review, current advances in GCA pathogenesis are discussed in different inflammatory phases. Through the description of these-often overlapping-phases, cells, molecules, and small lipid mediators with pathogenetic potential are described.

Tofacitinib: A Treatment Option for Recalcitrant Polymorphic Light Eruption and Its Mechanistic Rationale.

Background: Polymorphous light eruption is largely characterized by a delayed-type (type IV) hypersensitivity reaction to 1 or more undefined endogenous ultraviolet-induced skin antigens. Objectives: To evaluate the efficacy of tofacitinib in refractory cases of polymorphous light eruption. Methods: Seven patients who had failed multiple systemic treatments or relapsed within 2 weeks of existing systemic agents with concomitant photoprotection were offered tofacitinib after written consent. Results: Initiation of tofacitinib led to a marked reduction of itching (mean ± SD 3.1 ± 1.12 days) followed by clinical resolution (mean ± SD 2.6 ± 1.1 weeks). The duration of therapy ranged from 1 to 3 months (mean ± SD 2 ± 0.63 months), and 4 of 7 patients had a recurrence in 5.5 weeks and were again initiated on tofacitinib with a prompt response. Conclusion: Tofacitinib inhibits Janus kinase (JAK)1 and JAK3 thus it can abrogate the effects of the predominant cytokine milieu of polymorphic light eruption (PMLE) and thus reduce the expression of aberrant inflammatory T lymphocyte expression in PMLE.

Neutrophil infiltration in allergic contact dermatitis to nickel.

Allergic contact dermatitis (ACD) is traditionally recognized as a T-cell-mediated delayed-type hypersensitivity reaction. However, many patients with ACD have been reported to experience rapid-onset ACD reactions within hours of re-exposure on skin areas previously exposed to the contact allergen. In this study, three nickel-allergic patients were patch tested for nickel twice at the same skin site over 21 days. The results demonstrated that neutrophils are rapidly recruited to the skin sites previously exposed to nickel, leading to the rapid onset of ACD. Considering that many patients with ACD are frequently re-exposed to contact allergens on the same skin areas in their daily lives, we propose that mechanisms involved in neutrophil recruitment could be potential targets for future ACD treatment.

In Vitro and In Vivo Methods for Analysis of Nanoparticles' Potential toInduce Delayed-Type Hypersensitivity Reactions.

Delayed-type hypersensitivity (DTH) reactions are among the common reasons for drug withdrawal from clinical use during the post-marketing stage. Several in vivo methods have been developed to test DTH responses in animal models. They include the local lymph node assay (LLNA) and local lymph node proliferation assay (LLNP). While LLNA is instrumental in testing topically administered formulations (e.g., creams), the LLNP was proven to be predictive of drug-mediated DTH in response to small molecule pharmaceuticals. Global efforts in reducing the use of research animals lead to the development of in vitro models to predict test-materials' mediated DTH. Two such models include theanalysis of surface marker expression in human cell lines THP-1 and U-937. These tests are known as the human cell line activation test (hCLAT) and myeloid U937 skin sensitization test (MUSST or U-SENS), respectively. Here we describe experimental procedures for all these methods, discuss their in vitro-in vivo correlation, and suggest a strategy for applying these tests to analyze engineered nanomaterials and nanotechnology-formulated drug products.