Blog

Mil Med. 2023 Dec 21:usad480. doi: 10.1093/milmed/usad480. Online ahead of print.

ABSTRACT

Common variable immunodeficiency (CVID) is the most common symptomatic primary immunodeficiency. It is characterized by hypogammaglobulinemia and can present with a broad range of symptoms including recurrent bacterial infections, autoimmunity, and malignancy. Rarely, it has been implicated with peripheral neuropathy. We present a case of CVID with peripheral neuropathy and a pathogenic heterozygous variant of IL-7 receptor gene. The patient is a 38-year-old female with a history of recurrent infections since childhood including pneumonia and sinus infections status post tonsillectomy and sinus surgery. She subsequently developed severe left leg and lower back pain that progressed to left foot drop and decreased sensation over the left leg. She was found to have severe hypogammaglobulinemia and poor polysaccharide and protein response, thus meeting criteria for CVID. Mononeuropathy is a rare finding in CVID. Genetic panel was performed and was significant for a single pathogenic variant in IL-7 receptor. Disruptions in the IL-7 and IL-7 receptor signaling pathway have been associated with autoimmunity such as rheumatoid arthritis and multiple sclerosis. Further investigation is indicated to determine the clinical significance of this variant.

PMID:38126802 | DOI:10.1093/milmed/usad480

Commun Med (Lond). 2023 Dec 20;3(1):189. doi: 10.1038/s43856-023-00412-8.

ABSTRACT

BACKGROUND: Primary immunodeficiency (PI) is a group of heterogeneous disorders resulting from immune system defects. Over 70% of PI is undiagnosed, leading to increased mortality, co-morbidity and healthcare costs. Among PI disorders, combined immunodeficiencies (CID) are characterized by complex immune defects. Common variable immunodeficiency (CVID) is among the most common types of PI. In light of available treatments, it is critical to identify adult patients at risk for CID and CVID, before the development of serious morbidity and mortality.

METHODS: We developed a deep learning-based method (named “TabMLPNet”) to analyze clinical history from nationally representative medical claims from electronic health records (Optum® data, covering all US), evaluated in the setting of identifying CID/CVID in adults. Further, we revealed the most important CID/CVID-associated antecedent phenotype combinations. Four large cohorts were generated: a total of 47,660 PI cases and (1:1 matched) controls.

RESULTS: The sensitivity/specificity of TabMLPNet modeling ranges from 0.82-0.88/0.82-0.85 across cohorts. Distinctive combinations of antecedent phenotypes associated with CID/CVID are identified, consisting of respiratory infections/conditions, genetic anomalies, cardiac defects, autoimmune diseases, blood disorders and malignancies, which can possibly be useful to systematize the identification of CID and CVID.

CONCLUSIONS: We demonstrated an accurate method in terms of CID and CVID detection evaluated on large-scale medical claims data. Our predictive scheme can potentially lead to the development of new clinical insights and expanded guidelines for identification of adult patients at risk for CID and CVID as well as be used to improve patient outcomes on population level.

PMID:38123736 | DOI:10.1038/s43856-023-00412-8

Lancet Reg Health Eur. 2023 Oct 13;35:100747. doi: 10.1016/j.lanepe.2023.100747. eCollection 2023 Dec.

ABSTRACT

BACKGROUND: Immunocompromised individuals are not optimally protected by COVID-19 vaccines and potentially require additional preventive interventions to mitigate the risk of severe COVID-19. We aimed to characterise and describe the risk of severe COVID-19 across immunocompromised groups as the pandemic began to transition to an endemic phase.

METHODS: COVID-19-related hospitalisations, intensive care unit (ICU) admissions, and deaths (01/01/2022-31/12/2022) were compared among different groups of immunocompromised individuals vs the general population, using a retrospective cohort design and electronic health data from a random 25% sample of the English population aged ≥12 years (Registration number: ISRCTN53375662).

FINDINGS: Overall, immunocompromised individuals accounted for 3.9% of the study population, but 22% (4585/20,910) of COVID-19 hospitalisations, 28% (125/440) of COVID-19 ICU admissions, and 24% (1145/4810) of COVID-19 deaths in 2022. Restricting to those vaccinated with ≥3 doses of COVID-19 vaccine (∼84% of immunocompromised and 51% of the general population), all immunocompromised groups remained at increased risk of severe COVID-19 outcomes, with adjusted incidence rate ratios (aIRR) for hospitalisation ranging from 1.3 to 13.1. At highest risk for COVID-19 hospitalisation were individuals with: solid organ transplant (aIRR 13.1, 95% confidence interval [95% CI] 11.2-15.3), moderate to severe primary immunodeficiency (aIRR 9.7, 95% CI 6.3-14.9), stem cell transplant (aIRR 11.0, 95% CI 6.8-17.6), and recent treatment for haematological malignancy (aIRR 10.6, 95% CI 9.5-11.9). Results were similar for COVID-19 ICU admissions and deaths.

INTERPRETATION: Immunocompromised individuals continue to be impacted disproportionately by COVID-19 and have an urgent need for additional preventive measures beyond current vaccination programmes. These data can help determine the immunocompromised groups for which targeted prevention strategies may have the highest impact.

FUNDING: This study was funded by AstraZeneca UK.

PMID:38115964 | PMC:PMC10730312 | DOI:10.1016/j.lanepe.2023.100747

J Clin Immunol. 2023 Dec 19;44(1):4. doi: 10.1007/s10875-023-01614-4.

ABSTRACT

Mutations affecting T-cell receptor (TCR) signaling typically cause combined immunodeficiency (CID) due to varying degrees of disturbed T-cell homeostasis and differentiation. Here, we describe two cousins with CID due to a novel nonsense mutation in LCK and investigate the effect of this novel nonsense mutation on TCR signaling, T-cell function, and differentiation. Patients underwent clinical, genetic, and immunological investigations. The effect was addressed in primary cells and LCK-deficient T-cell lines after expression of mutated LCK. RESULTS: Both patients primarily presented with infections in early infancy. The LCK mutation led to reduced expression of a truncated LCK protein lacking a substantial part of the kinase domain and two critical regulatory tyrosine residues. T cells were oligoclonal, and especially naïve CD4 and CD8 T-cell counts were reduced, but regulatory and memory including circulating follicular helper T cells were less severely affected. A diagnostic hallmark of this immunodeficiency is the reduced surface expression of CD4. Despite severely impaired TCR signaling mTOR activation was partially preserved in patients’ T cells. LCK-deficient T-cell lines reconstituted with mutant LCK corroborated partially preserved signaling. Despite detectable differentiation of memory and effector T cells, their function was severely disturbed. NK cell cytotoxicity was unaffected. Residual TCR signaling in LCK deficiency allows for reduced, but detectable T-cell differentiation, while T-cell function is severely disturbed. Our findings expand the previous report on one single patient on the central role of LCK in human T-cell development and function.

PMID:38112969 | DOI:10.1007/s10875-023-01614-4

Proc Natl Acad Sci U S A. 2023 Dec 26;120(52):e2310221120. doi: 10.1073/pnas.2310221120. Epub 2023 Dec 18.

ABSTRACT

The 21kD GTPase Rac is an evolutionarily ancient regulator of cell shape and behavior. Rac2 is predominantly expressed in hematopoietic cells where it is essential for survival and motility. The hyperactivating mutation Rac2^E62K also causes human immunodeficiency, although the mechanism remains unexplained. Here, we report that in Drosophila, hyperactivating Rac stimulates ovarian cells to cannibalize neighboring cells, destroying the tissue. We then show that hyperactive Rac2^E62K stimulates human HL60-derived macrophage-like cells to engulf and kill living T cell leukemia cells. Primary mouse Rac2^+/E62K bone-marrow-derived macrophages also cannibalize primary Rac2^+/E62K T cells due to a combination of macrophage hyperactivity and T cell hypersensitivity to engulfment. Additionally, Rac2^+/E62K macrophages non-autonomously stimulate wild-type macrophages to engulf T cells. Rac2^E62K also enhances engulfment of target cancer cells by chimeric antigen receptor-expressing macrophages (CAR-M) in a CAR-dependent manner. We propose that Rac-mediated cell cannibalism may contribute to Rac2^+/E62K human immunodeficiency and enhance CAR-M cancer immunotherapy.

PMID:38109551 | DOI:10.1073/pnas.2310221120

J Ethnopharmacol. 2023 Dec 14:117575. doi: 10.1016/j.jep.2023.117575. Online ahead of print.

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: The occurrence and development of atherosclerosis, a common chronic inflammatory vascular disease, are closely related to cardiovascular and cerebrovascular diseases. Banxia Baizhu Tianma Decoction (BBTD) is a representative traditional Chinese medicine formula that resolves phlegm, disperses wind, invigorates the spleen and eliminates dampness and is also a commonly used clinical medication for treating vascular diseases.

AIM OF THE STUDY: To explore the pharmacological mechanisms of BBTD in alleviating atherosclerosis, the present study was carried out by conducting an integrative analysis of aortic and perivascular adipose tissue (PVAT) proteomics and metabolomics.

MATERIALS AND METHODS: Eight-week-old ApoE-/- mice were randomly divided into the BBTD group and the model group, and nine age-matched C57BL/6J (C57) mice were used as the control group (n = 9). The C57 mice were fed a standard diet, while the ApoE^-/- mice were fed a high-fat, high-cholesterol diet for 12 weeks. Mice in the BBTD group were transgastrically administered BBTD at a dose of 17.8 g/kg/day for 8 weeks, while the model group and control group mice received an equivalent volume of saline by gavage. Histomorphology of the aortas and PVAT was assessed by HE staining, oil red O staining, Masson staining, and α-SMA and CD68 immunohistochemical methods. An integrative analysis of aortic proteomics, PVAT proteomics and PVAT metabolomics was conducted to study the pharmacological mechanisms of BBTD.

RESULTS: Compared to the model group, mice treated with BBTD had thicker fibrous caps, increased collagen content, less erosion of smooth muscle cells and infiltration of macrophages, as well as a relatively low inflammatory response level, suggesting that BBTD treatment reduced plaque vulnerability. Omics analysis suggested that BBTD treatment demonstrated anti-atherosclerotic effects and increased plaque stability in the aorta by activating the TGF-beta pathway. Simultaneously, BBTD inhibited PVAT inflammation levels (decreased the levels of MCP and IL-6). Proteomics and metabolomics of PVAT suggested that the targets of BBTD included upregulation of the α-linolenic acid metabolic pathway and downregulation of multiple inflammatory pathways, such as the NF-kappa B signalling pathway, primary immunodeficiency and Th17 cell differentiation in PVAT.

CONCLUSIONS: BBTD reduces the vulnerability of atherosclerotic plaques and inhibits the inflammatory phenotype of perivascular adipose tissue.

PMID:38103846 | DOI:10.1016/j.jep.2023.117575

J Clin Immunol. 2023 Dec 15;44(1):2. doi: 10.1007/s10875-023-01627-z.

ABSTRACT

The DNA polymerase δ complex (PolD), comprising catalytic subunit POLD1 and accessory subunits POLD2, POLD3, and POLD4, is essential for DNA synthesis and is central to genome integrity. We identified, by whole exome sequencing, a homozygous missense mutation (c.1118A > C; p.K373T) in POLD3 in a patient with Omenn syndrome. The patient exhibited severely decreased numbers of naïve T cells associated with a restricted T-cell receptor repertoire and a defect in the early stages of TCR recombination. The patient received hematopoietic stem cell transplantation at age 6 months. He manifested progressive neurological regression and ultimately died at age 4 years. We performed molecular and functional analysis of the mutant POLD3 and assessed cell cycle progression as well as replication-associated DNA damage. Patient fibroblasts showed a marked defect in S-phase entry and an enhanced number of double-stranded DNA break-associated foci despite normal expression levels of PolD components. The cell cycle defect was rescued by transduction with WT POLD3. This study validates autosomal recessive POLD3 deficiency as a novel cause of profound T-cell deficiency and Omenn syndrome.

PMID:38099988 | DOI:10.1007/s10875-023-01627-z

Front Pediatr. 2023 Nov 30;11:1329023. doi: 10.3389/fped.2023.1329023. eCollection 2023.

NO ABSTRACT

PMID:38098642 | PMC:PMC10720881 | DOI:10.3389/fped.2023.1329023

Ann Med Surg (Lond). 2023 Oct 20;85(12):5859-5862. doi: 10.1097/MS9.0000000000001436. eCollection 2023 Dec.

NO ABSTRACT

PMID:38098588 | PMC:PMC10718386 | DOI:10.1097/MS9.0000000000001436

Georgian Med News. 2023 Oct;(343):199-203.

ABSTRACT

Primary Immunodeficiency Disease (PID) represents a class of diverse illnesses marked by compromised immune system performance. For better patient outcomes, PIDs must be diagnosed and treated quickly. Medical graduates are essential to the detection and treatment of these illnesses. The purpose of this study was to evaluate medical students’ knowledge about PIDs in different Indian medical colleges. To perform this analytical investigation, college students from Maharashtra-area universities were enlisted between March and April of 2023. The participants received a questionnaire from mediators from every institution. Of the 500 students in the study, 66% were between the ages of 22 and 24 and 52% were female. Their understanding ratings had an average of 16.3±6.2 and varied between 4 and 32. A set of students classified as below average (86%) and a mean/above average (14%), were separated among the students. The largest percentage of above-average knowledge was demonstrated by VI-year participants (p<0.05). This investigation emphasizes how critical it is to provide focused educational activities to improve medical students’ comprehension of PIDs in India.

PMID:38096540