Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To identify genes and mechanisms involved in humoral immunity, we did a mouse genetic screen for mutations that do not affect the first wave of antibody to immunization but disrupt response maturation and persistence. The first two mutants identified had loss-of-function mutations in the gene encoding a previously obscure member of a family of Rho-Rac GTP-exchange factors, DOCK8. DOCK8-mutant B cells were unable to form marginal zone B cells or to persist in germinal centers and undergo affinity maturation. Dock8 mutations disrupted accumulation of the integrin ligand ICAM-1 in the B cell immunological synapse but did not alter other aspects of B cell antigen receptor signaling. Humoral immunodeficiency due to Dock8 mutation provides evidence that organization of the immunological synapse is critical for signaling the survival of B cell subsets required for long-lasting immunity.
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PMID:Dock8 mutations cripple B cell immunological synapses, germinal centers and long-lived antibody production. 1991 22

Hyperimmunoglobulin-E syndrome (HIES) is one of the primary immunodeficiency with the manifestations of recurrent infections especially with Staphylococcus aureus, characteristic facies, hyperextensibility of joints, multiple bone fractures, scoliosis, and delayed shedding of the primary teeth. It is a multisystem disease of autosomal dominant or recessive inheritance. Recently, the genetic causes of HIES (STAT3, TYK2, and DOCK8) were clarified.
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PMID:[Recent advances in the pathogenesis of hyper IgE syndrome]. 2019 May 5

Autosomal-recessive hyper-IgE syndrome (AR-HIES) is a combined immunodeficiency recently found to be associated with mutations of DOCK8. Clinically, this disorder is characterized beside recurrent bacterial complications, in particular by an unusual susceptibility to extensive cutaneous viral complications and by a high risk for squamous cell carcinoma. Here, we report on lasting control over the disorder in two patients by hematopoietic cell transplantation (HCT). Both patients were suffering from extensive long-lasting cutaneous viral complications, in particular from disfiguring molluscum contagiosum infections, when treated at the age of 10 and 17 years. Donors were matched unrelated, and conditioning was carried out with a combination of fludarabine, melphalan and BM-targeted radioimmunotherapy. Both patients developed stable, full donor cell chimerism, with the exception of persistent low-IgA serum levels and the exception of normal immune functions. Over the course of several months, cutaneous manifestations of viral disease resolved completely and both patients remain clinically well and free of infectious complications at 4 and 2 years, respectively, after transplantation. This represents the first report indicating HCT to be curative in patients with AR-HIES, which should be considered early before life-threatening complications develop, which include malignancies.
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PMID:Curative treatment of autosomal-recessive hyper-IgE syndrome by hematopoietic cell transplantation. 2062 10

DOCK8 immunodeficiency syndrome (DIDS) is a combined immunodeficiency characterized by recurrent viral infections, severe atopy, and early onset malignancy. Genetic studies revealed large, unique deletions in patients from different families and ethnic backgrounds. Clinical markers of DIDS include atopic dermatitis, allergies, cutaneous viral infections, recurrent respiratory tract infections, and malignancy. Immune assessments showed T cell lymphopenia, hyper-IgE, hypo-IgM, and eosinophilia. The impaired lymphocyte functions in DIDS patients appear central for disease pathogenesis.
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PMID:Genetic, clinical, and laboratory markers for DOCK8 immunodeficiency syndrome. 2117 72

The processes that normally generate and maintain adaptive immunity and immunological memory are poorly understood, and yet of fundamental importance when infectious diseases place such a major economic and social burden on the world's health and agriculture systems. Defects in these mechanisms also underlie the many forms of human primary immunodeficiency. Identifying these mechanisms in a systematic way is therefore important if we are to develop better strategies for treating and preventing infection, inherited disease, transplant rejection and autoimmunity. In this review we describe a genome-wide screen in mice for the genes important for generating these adaptive responses, and describe two independent DOCK8 mutant mice strains identified by this screen. DOCK 8 was found to play an essential role in humoral immune responses and to be important in the proper formation of the B cell immunological synapse.
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PMID:The essential role of DOCK8 in humoral immunity. 2117 73

Hyper-immunoglobulin E recurrent infection syndromes (HIES) have distinct features, with identified associated mutations of STAT3, TYK2, and DOCK8. Among 197 Taiwanese patients with primary immunodeficiency on a referral-base of over 23 million inhabitants, STAT3 (R382W and Q469R) and DOCK8 mutations (exon 1-9 deletion) were identified in two patients each from six AD-HIES and five AR-HIES patients, respectively. Aside from decreased Th17 and memory B cells, characteristic facies and pneumatocele were not mutually exclusive regardless of STAT3 and DOCK8 mutations. One with novel DOCK8 deletion had notable cytomegalovirus retinitis, cerebral vasculitis, lead deposition, and amenorrhea. In adolescence, three AD-HIES patients without STAT3 mutation died of myocardial infarction, staphylococcus sepsis, and proteus sepsis while receiving chemotherapy for lymphoma. Close follow-up of the HIES phenotype rather than identifying genetic mutations should be the cornerstone of intervention at this juncture because of relatively lower percentage of identifying mutations in Taiwanese HIES (4/11; 36.5%).
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PMID:Clinical, immunological and genetic features in Taiwanese patients with the phenotype of hyper-immunoglobulin E recurrent infection syndromes (HIES). 2132 46

Loss of function of DOCK8 is the major cause of autosomal recessive hyper IgE syndrome, a primary immunodeficiency with adaptive and innate immune dysfunction. Patients affected with ARHIES have atopic dermatitis and recurrent, potentially life-threatening viral and bacterial infections. Three consanguineous Pakistani siblings presented with severe atopic dermatitis and superinfection. Direct sequencing of DOCK8 in all three affected siblings demonstrated homozygosity for a deleterious, novel exon 14 frame shift mutation. Current newborn screening for severe combined immunodeficiency syndrome (SCID) and related T cell disorders relies on the quantitation of T Cell Receptor Excision Cells (TRECs) in dried blood spots (DBS). Significantly, both older affected siblings had undetectable TRECs, and TREC copy number was reduced in the youngest sibling. These findings suggest that AR-HIES may be detected by TREC newborn screening, and this diagnosis should be considered in the evaluation of newborns with abnormal TRECs who do not have typical SCID.
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PMID:Deficient T Cell Receptor Excision Circles (TRECs) in autosomal recessive hyper IgE syndrome caused by DOCK8 mutation: implications for pathogenesis and potential detection by newborn screening. 2187 21

In humans, DOCK8 immunodeficiency syndrome is characterized by severe cutaneous viral infections. Thus, CD8 T cell function may be compromised in the absence of DOCK8. In this study, by analyzing mutant mice and humans, we demonstrate a critical, intrinsic role for DOCK8 in peripheral CD8 T cell survival and function. DOCK8 mutation selectively diminished the abundance of circulating naive CD8 T cells in both species, and in DOCK8-deficient humans, most CD8 T cells displayed an exhausted CD45RA(+)CCR7(-) phenotype. Analyses in mice revealed the CD8 T cell abnormalities to be cell autonomous and primarily postthymic. DOCK8 mutant naive CD8 T cells had a shorter lifespan and, upon encounter with antigen on dendritic cells, exhibited poor LFA-1 synaptic polarization and a delay in the first cell division. Although DOCK8 mutant T cells underwent near-normal primary clonal expansion after primary infection with recombinant influenza virus in vivo, they showed greatly reduced memory cell persistence and recall. These findings highlight a key role for DOCK8 in the survival and function of human and mouse CD8 T cells.
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PMID:DOCK8 deficiency impairs CD8 T cell survival and function in humans and mice. 2200 77

The discovery that loss-of-function mutations in the gene DOCK8 are responsible for most forms of autosomal recessive hyper-IgE syndrome and some forms of combined immunodeficiency without elevated serum IgE has led to studies into the immunopathogenesis of this disease. In this review, we relate the clinical features of this disease to studies using patients' cells and a mouse model of Dock8 deficiency, which have revealed how DOCK8 regulates T and B cell numbers and functions. The results of these studies help to explain how the absence of DOCK8 contributes to patients' susceptibility to viral, fungal, and bacterial infections. However, unanswered questions remain regarding how the absence of DOCK8 also leads to high IgE and allergic disease, predisposition for malignancy, and unusual clinical features, such as CNS abnormalities and autoimmunity, observed in some patients.
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PMID:DOCK8 deficiency. 2223 27

To migrate efficiently through the interstitium, dendritic cells (DCs) constantly adapt their shape to the given structure of the extracellular matrix and follow the path of least resistance. It is known that this amoeboid migration of DCs requires Cdc42, yet the upstream regulators critical for localization and activation of Cdc42 remain to be determined. Mutations of DOCK8, a member of the atypical guanine nucleotide exchange factor family, causes combined immunodeficiency in humans. In the present study, we show that DOCK8 is a Cdc42-specific guanine nucleotide exchange factor that is critical for interstitial DC migration. By generating the knockout mice, we found that in the absence of DOCK8, DCs failed to accumulate in the lymph node parenchyma for T-cell priming. Although DOCK8-deficient DCs migrated normally on 2-dimensional surfaces, DOCK8 was required for DCs to crawl within 3-dimensional fibrillar networks and to transmigrate through the subcapsular sinus floor. This function of DOCK8 depended on the DHR-2 domain mediating Cdc42 activation. DOCK8 deficiency did not affect global Cdc42 activity. However, Cdc42 activation at the leading edge membrane was impaired in DOCK8-deficient DCs, resulting in a severe defect in amoeboid polarization and migration. Therefore, DOCK8 regulates interstitial DC migration by controlling Cdc42 activity spatially.
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PMID:DOCK8 is a Cdc42 activator critical for interstitial dendritic cell migration during immune responses. 2246 90


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