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Blood Transfusion = Trasfusione Del... Jun 2024Transfusion medicine is facing new challenges from therapies which interfere with pre-transfusional tests, such as monoclonal antibodies targeting blood-cell antigens....
BACKGROUND
Transfusion medicine is facing new challenges from therapies which interfere with pre-transfusional tests, such as monoclonal antibodies targeting blood-cell antigens. Anti-CD38 monoclonal antibodies, widely used to treat multiple myeloma, cause panreactivity of indirect antiglobulin test; this can be resolved by treating cells with dithiothreitol to disrupt the CD38 disulphide bonds expressed on red blood cell surfaces. Interference mitigation strategy with dithiothreitol, however, has some drawbacks: it entails losing the traceability of results and the denaturation of blood group systems sensitive to reducing agents; it takes time to perform and quality controls are lost.
MATERIALS AND METHODS
Panels were treated with 0.2 mol/L dithiothreitol and stored for 30 days with a commercial preservative solution. On day 30, we measured the hemolysis indices and ability to eliminate daratumumab and isatuximab interference in the treated cells using indirect antiglobulin test. We also tested the stability of erythrocyte antigenic structure by screening 42 samples with known antibodies; tests were repeated on day 1, 7, 15 and 30. All indirect antiglobulin testing was performed on gel card.
RESULTS
After 30 days from treatment, panels preserved in preservative solution showed hemolysis indices comparable to untreated panels: all cases of interference by anti-CD38 in pre-transfusional tests were successfully mitigated. All antibodies were detected after 30 days, except for KEL system antibodies, as expected, although there was a detectability of anti-Kell antibodies in high titer samples (the first detection in dithiothreitol-treated cells since 1983).
DISCUSSION
We propose the Extended Lifetime Protocol; a simple card-based method which is cheap and traceable, that combines the strengths of anti-CD38 mitigation strategies. It makes it possible to treat and store, at the same time, a sufficient volume of red blood cells, that can be used for the following 30 days, to avoid any delay in transfusional requests.
PubMed: 38949853
DOI: 10.2450/BloodTransfus.779 -
Polish Archives of Internal Medicine Jul 2024There is little data on the development of dermal lesions in patients with inflammatory bowel disease (IBD) treated with anti - tumor necrosis factor-α (anti-TNF-α),...
Dermal lesions associated with anti-tumor necrosis factor-α therapy in patients with inflammatory bowel disease: findings from an inflammatory bowel disease tertiary center in Poland.
INTRODUCTION
There is little data on the development of dermal lesions in patients with inflammatory bowel disease (IBD) treated with anti - tumor necrosis factor-α (anti-TNF-α), while their characteristics, clinical course, and impact on treatment are of great concern.
OBJECTIVES
The aim of this study is to assess the prevalence, risk factors, and clinical sequelae of dermal lesions in IBD patients treated with anti-TNF-α antibodies.
PATIENTS AND METHODS
This retrospective, single-center study evaluated 541 IBD patients treated with anti-TNF-α drugs and compared them with 688 IBD anti-TNF-α-naïve patients.
RESULTS
A significant higher prevalence of dermal lesions was noted during the anti-TNF-α therapy of 30.9% patients versus 16.4% (P <0.001). Risk factors for dermal lesions were higher body mass index (BMI), Crohn's disease located in the small intestine, and longer duration of therapy. Some types of dermal lesions were associated with anti-TNF-α therapy: infusion reactions and injection site reactions, cutaneous infection, psorasiform reactions, and lupus-like symptoms. Dermal lesions (alopecia, lupus-like symptoms, melanoma, and psoriasis) occurred in 5.9% of patients who discontinued or changed anti-TNF-α therapy.
CONCLUSIONS
We observed a higher prevalence of dermal lesions in patients with IBD undergoing anti-TNF-α therapy, although the development of such lesions rarely necessitated a change in or discontinuation of treatment. Patients with IBD should undergo regular dermatological follow-up, which may improve the detection of dermal lesions. Moreover, biological therapy in IBD patients requires close collaboration with an experienced dermatologist.
PubMed: 38949562
DOI: 10.20452/pamw.16789 -
JPMA. the Journal of the Pakistan... Jun 2024Common variable immunodeficiency (CVID) is the most prevalent primary immunodeficiency disorder with different phenotypes and aetiologies. It is characterised by...
Common variable immunodeficiency (CVID) is the most prevalent primary immunodeficiency disorder with different phenotypes and aetiologies. It is characterised by hypogammaglobulinaemia, defects in specific antibody response, erroneous activation and proliferation of T cells, leading to increased risk of recurrent infections. In CVID, "Variable" refers to the heterogeneity of clinical presentations, which include recurrent infections, autoimmunity, enteropathy, and increased risk of malignancies. This wide spectrum of disease manifestations and being a diagnosis of exclusion poses a diagnostic challenge. It is pertinent to mention that CVID along with associated complications is the commonest symptomatic primary antibody deficiency but is scarcely mentioned in local literature. The main aim of presenting this case is to impress upon the importance of systematic immunological workup in cases of suspected immunodeficiency to prevent morbidity and mortality.
Topics: Humans; Common Variable Immunodeficiency; Developing Countries; Male; Female; Adult
PubMed: 38948994
DOI: 10.47391/JPMA.9376 -
BioRxiv : the Preprint Server For... Jun 2024The serotonin 2A receptor (5-HT R) and the metabotropic glutamate 2 receptor (mGluR2) form heteromeric G protein-coupled receptor (GPCR) complexes through a direct...
The serotonin 2A receptor (5-HT R) and the metabotropic glutamate 2 receptor (mGluR2) form heteromeric G protein-coupled receptor (GPCR) complexes through a direct physical interaction. Co-translational association of mRNAs encoding subunits of heteromeric ion channels has been reported, but whether complex assembly of GPCRs occurs during translation remains unknown. Our data reveal evidence of co-translational modulation in and mRNAs following siRNA-mediated knockdown. Interestingly, immunoprecipitation of either 5-HT R or mGluR2, using an antibody targeting epitope tags at their N-terminus, results in detection of both transcripts associated with ribonucleoprotein complexes containing RPS24. Additionally, we demonstrate that the mRNA transcripts of and associate autonomously of their respective encoded proteins. Validation of this translation-independent association is extended using mouse frontal cortex samples. Together, these findings provide mechanistic insights into the co-translational assembly of GPCR heteromeric complexes, unraveling regulatory processes governing protein-protein interactions and complex formation.
PubMed: 38948858
DOI: 10.1101/2024.06.17.599432 -
BioRxiv : the Preprint Server For... Jun 2024The renin-angiotensin system is a highly characterized integrative pathway in mammalian homeostasis whose clinical spectrum has been expanded to lung disorders such as...
The renin-angiotensin system is a highly characterized integrative pathway in mammalian homeostasis whose clinical spectrum has been expanded to lung disorders such as chronic obstructive pulmonary disease (COPD)-emphysema, idiopathic pulmonary fibrosis (IPF), and COVID pathogenesis. Despite this widespread interest, specific localization of this receptor family in the mammalian lung is limited, partially due to the imprecision of available antibody reagents. In this study, we establish the expression pattern of the two predominant angiotensin receptors in the human lung, and , using complementary and comprehensive bulk and single-cell RNA-sequence datasets that are publicly available. We show these two receptors have distinct localization patterns and developmental trajectories in the human lung, pericytes for and a subtype of alveolar epithelial type 2 cells for . In the context of disease, we further pinpoint localization to the COPD-associated subpopulation of alveolar epithelial type 2 (AT2 ) and localization to fibroblasts, where their expression is upregulated in individuals with COPD, but not in individuals with IPF. Finally, we examine the genetic variation of the angiotensin receptors, finding associated with lung phenotype (i.e., cystic fibrosis) via rs1403543. Together, our findings provide a critical foundation for delineating this pathway's role in lung homeostasis and constructing rational approaches for targeting specific lung disorders.
PubMed: 38948835
DOI: 10.1101/2024.06.17.599425 -
BioRxiv : the Preprint Server For... Jun 2024The extent to which live orally-administered rotavirus (RV) vaccines elicit protective immunity is highly heterogeneous. We hypothesized microbiota composition might...
BACKGROUND & AIMS
The extent to which live orally-administered rotavirus (RV) vaccines elicit protective immunity is highly heterogeneous. We hypothesized microbiota composition might influence vaccine efficacy.
METHODS
We tested this concept by examining extent to which colonizing mice with segmented filamentous bacteria (SFB) influenced RV vaccine efficacy.Influence of human microbiomes on RV vaccination was studied via administering germ-free mice fecal microbial transplants (FMT) from children with robust or minimal RV vaccine responsiveness. Post-FMT, mice were subjected to vaccination and challenge doses of RV.
RESULTS
SFB administration resulted in a phenotype reminiscent of RV vaccine failure, i.e. minimal generation of RV antigens and, consequently, lack of anti-RV antibodies resulting in proneness to RV challenge once SFB levels diminished. Transplant of microbiomes from children to mice recapitulated donor vaccination phenotype. Specifically, mice receiving FMT from high-responding children exhibited high levels of fecal RV antigen shedding and RV antibodies in response to RV vaccination and, concomitantly, were impervious to RV challenge. In contrast, mice receiving FMT from children who had not responded to RV vaccination exhibited only modest responses to RV challenge and, accordingly, remained prone to RV challenge. Microbiome analysis ruled out a role for SFB but suggested that RV vaccine failure might involve . Oral administration of cultured to gnotobiotic mice partially recapitulated the RV vaccine non-responder phenotype. Analysis of previously-reported microbiome data found C. perfringens abundance in children associated with RV vaccine failure.
CONCLUSION
Microbiota composition influences RV vaccine virus infection and, consequently, protective immunity. may be one, perhaps of many, bacterial species harbored in the intestine of RV-vaccine non-responders that influences RV vaccine outcomes.
PubMed: 38948828
DOI: 10.1101/2024.06.17.599343 -
BioRxiv : the Preprint Server For... Jun 2024Both endogenous antibodies and a subset of antibody therapeutics engage Fc gamma receptor (FcγR)IIIa / CD16a to stimulate a protective immune response. Increasing the...
Both endogenous antibodies and a subset of antibody therapeutics engage Fc gamma receptor (FcγR)IIIa / CD16a to stimulate a protective immune response. Increasing the FcγRIIIa/IgG1 interaction improves the immune response and thus represents a strategy to improve therapeutic efficacy. FcγRIIIa is a heavily glycosylated receptor and glycan composition affects antibody-binding affinity. Though our laboratory previously demonstrated that natural killer (NK) cell N-glycan composition affected the potency of one key protective mechanism, antibody-dependent cell-mediated cytotoxicity (ADCC), it was unclear if this effect was due to FcγRIIIa glycosylation. Furthermore, the structural mechanism linking glycan composition to affinity and cellular activation remained undescribed. To define the role of individual amino acid and N-glycan residues we measured affinity using multiple FcγRIIIa glycoforms. We observed stepwise affinity increases with each glycan truncation step with the most severely truncated glycoform displaying the highest affinity. Removing the N162 glycan demonstrated its predominant role in regulating antibody-binding affinity, in contrast to four other FcγRIIIa N-glycans. We next evaluated the impact of the N162 glycan on NK cell ADCC. NK cells expressing the FcγRIIIa V158 allotype exhibited increased ADCC following kifunensine treatment to limit N-glycan processing. Notably, an increase was not observed with cells expressing the FcγRIIIa V158 S164A variant that lacks N162 glycosylation, indicating the N162 glycan is required for increased NK cell ADCC. To gain structural insight into the mechanisms of N162 regulation, we applied a novel protein isotope labeling approach in combination with solution NMR spectroscopy. FG loop residues proximal to the N162 glycosylation site showed large chemical shift perturbations following glycan truncation. These data support a model for the regulation of FcγRIIIa affinity and NK cell ADCC whereby composition of the N162 glycan stabilizes the FG loop and thus the antibody-binding site.
PubMed: 38948809
DOI: 10.1101/2024.06.17.599285 -
BioRxiv : the Preprint Server For... Jun 2024Flow cytometry is a widely used technique for immune cell analysis, offering insights into cell composition and function. Spectral flow cytometry allows for...
Flow cytometry is a widely used technique for immune cell analysis, offering insights into cell composition and function. Spectral flow cytometry allows for high-dimensional analysis of immune cells, overcoming limitations of conventional flow cytometry. However, analyzing data from large antibody panels can be challenging using traditional bi-axial gating strategies. Here, we present a novel analysis pipeline designed to improve analysis of spectral flow cytometry. We employ this method to identify rare T cell populations in aging. We isolated splenocytes from young (2-3 months) and aged (18-19 months) female mice then stained these with a panel of 20 fluorescently labeled antibodies. Spectral flow cytometry was performed, followed by data processing and analysis using Python within a Jupyter Notebook environment to perform batch correction, unsupervised clustering, dimensionality reduction, and differential expression analysis. Our analysis of 3,776,804 T cells from 11 spleens revealed 34 distinct T cell clusters identified by surface marker expression. We observed significant differences between young and aged mice, with certain clusters enriched in one age group over the other. Naïve, effector memory, and central memory CD8 and CD4 T cell subsets exhibited age-associated changes in abundance and marker expression. Additionally, γδ T cell clusters showed differential abundance between age groups. By leveraging high-dimensional analysis methods borrowed from single-cell RNA sequencing analysis, we identified age-related differences in T cell subsets, providing insights into the immune aging process. This approach offers a robust, free, and easily implemented analysis pipeline for spectral flow cytometry data that may facilitate the discovery of novel therapeutic targets for age-related immune dysfunction.
PubMed: 38948780
DOI: 10.1101/2024.06.19.599633 -
BioRxiv : the Preprint Server For... Jun 2024Cachexia is a wasting syndrome comprised of adipose, muscle, and weight loss observed in cancer patients. Tumor loss-of-function mutations in , a regulator of the...
Cachexia is a wasting syndrome comprised of adipose, muscle, and weight loss observed in cancer patients. Tumor loss-of-function mutations in , a regulator of the energy sensor AMP-activated protein kinase, induce cancer cachexia (CC) in preclinical models and are associated with cancer-related weight loss in NSCLC patients. Here we characterized the relevance of the NSCLC-associated cachexia factor growth differentiation factor 15 (GDF15) in several patient-derived and genetically engineered -mutant NSCLC cachexia lines. Both tumor mRNA expression and serum concentrations of tumor-derived GDF15 were significantly elevated in multiple mice transplanted with patient-derived -mutated NSCLC lines. GDF15 neutralizing antibody administered to mice transplanted with patient- or mouse-derived -mutated NSCLC lines suppressed cachexia-associated adipose loss, muscle atrophy, and changes in body weight. The silencing of in multiple human NSCLC lines was also sufficient to eliminate circulating GDF15 levels and abrogate cachexia induction, suggesting that tumor and not host tissues represent a key source of GDF15 production in these cancer models. Finally, reconstitution of wild-type in a human loss-of-function NSCLC line that normally induces cachexia correlated with the absence of tumor-secreted GDF15 and rescue from the cachexia phenotype. The current data provide evidence for tumor-secreted GDF15 as a conduit and a therapeutic target through which NSCLCs with loss-of-function mutations promote cachexia-associated wasting.
PubMed: 38948776
DOI: 10.1101/2024.06.14.598891 -
BioRxiv : the Preprint Server For... Jun 2024Patients aged 65 years and older account for an increasing proportion of patients with traumatic brain injury (TBI). Older TBI patients experience increased morbidity...
UNLABELLED
Patients aged 65 years and older account for an increasing proportion of patients with traumatic brain injury (TBI). Older TBI patients experience increased morbidity and mortality compared to their younger counterparts. Our prior data demonstrated that by blocking α4 integrin, anti-CD49d antibody (aCD49d Ab) abrogates CD8+ T-cell infiltration into the injured brain, improves survival, and attenuates neurocognitive deficits. Here, we aimed to uncover how aCD49d Ab treatment alters local cellular responses in the aged mouse brain. Consequently, mice incur age-associated toxic cytokine and chemokine responses long-term post-TBI. aCD49d Ab attenuates this response along with a T helper (Th)1/Th17 immunological shift and remediation of overall CD8+ T cell cytotoxicity. Furthermore, aCD49d Ab reduces CD8+ T cells exhibiting higher effector status, leading to reduced clonal expansion in aged, but not young, mouse brains with chronic TBI. Together, aCD49d Ab is a promising therapeutic strategy for treating TBI in the older people.
GRAPHIC ABSTRACT
. The aged brain has long been resided by a population of CD8 T cells that's exhaustive and dysfunctional. Post TBI, due to BBB impairment, functional CD8 T cells primarily migrate into the brain parenchyma. Aged, injury-associated microglia with upregulated MHC class I molecules can present neoantigens such as neuronal and/or myelin debris in the injured brains to functional CD8+ T, resulting in downstream CD8+ T cell cytotoxicity. aCD49d Ab treatment exerts its function by blocking the migration of functional effector CD8 T cell population, leading to less cytotoxicity and resulting in improved TBI outcomes in aged mice.
PubMed: 38948775
DOI: 10.1101/2024.06.17.596673