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Inherited CARD9 deficiency in otherwise healthy children and adults with Candida species-induced meningoencephalitis, colitis, or both.

February 24, 2015 By Manish Butte

Inherited CARD9 deficiency in otherwise healthy children and adults with Candida species-induced meningoencephalitis, colitis, or both.

J Allergy Clin Immunol. 2015 Feb 19;

Authors: Lanternier F, Mahdaviani SA, Barbati E, Chaussade H, Koumar Y, Levy R, Denis B, Brunel AS, Martin S, Loop M, Peeters J, de Selys A, Vanclaire J, Vermylen C, Nassogne MC, Chatzis O, Liu L, Migaud M, Pedergnana V, Desoubeaux G, Jouvion G, Chretien F, Darazam IA, Schäffer AA, Netea MG, De Bruycker JJ, Bernard L, Reynes J, Amazrine N, Abel L, Van der Linden D, Harrison T, Picard C, Lortholary O, Mansouri D, Casanova JL, Puel A

Abstract
BACKGROUND: Invasive infections of the central nervous system (CNS) or digestive tract caused by commensal fungi of the genus Candida are rare and life-threatening. The known risk factors include acquired and inherited immunodeficiencies, with patients often displaying a history of multiple infections. Cases of meningoencephalitis, colitis, or both caused by Candida species remain unexplained.
OBJECTIVE: We studied 5 previously healthy children and adults with unexplained invasive disease of the CNS, digestive tract, or both caused by Candida species. The patients were aged 39, 7, 17, 37, and 26 years at the time of infection and were unrelated, but each was born to consanguineous parents of Turkish (2 patients), Iranian, Moroccan, or Pakistani origin. Meningoencephalitis was reported in 3 patients, meningoencephalitis associated with colitis was reported in a fourth patient, and the fifth patient had colitis only.
METHODS: Inherited caspase recruitment domain family, member 9 (CARD9) deficiency was recently reported in otherwise healthy patients with other forms of severe disease caused by Candida, Trichophyton, Phialophora, and Exophiala species, including meningoencephalitis but not colitis caused by Candida and Exophiala species. Therefore we sequenced CARD9 in the 5 patients.
RESULTS: All patients were found to be homozygous for rare and deleterious mutant CARD9 alleles: R70W and Q289* for the 3 patients with Candida albicans-induced meningoencephalitis, R35Q for the patient with meningoencephalitis and colitis caused by Candida glabrata, and Q295* for the patient with Candida albicans-induced colitis. Regardless of their levels of mutant CARD9 protein, the patients’ monocyte-derived dendritic cells responded poorly to CARD9-dependent fungal agonists (curdlan, heat-killed C albicans, Saccharomyces cerevisiae, and Exophiala dermatitidis).
CONCLUSION: Invasive infections of the CNS or digestive tract caused by Candida species in previously healthy children and even adults might be caused by inherited CARD9 deficiency.

PMID: 25702837 [PubMed – as supplied by publisher]

Detection of impaired IgG antibody formation facilitates the decision on early immunoglobulin replacement in hypogammaglobulinemic patients.

February 24, 2015 By Manish Butte

Detection of impaired IgG antibody formation facilitates the decision on early immunoglobulin replacement in hypogammaglobulinemic patients.

Front Immunol. 2015;6:32

Authors: Wolf HM, Thon V, Litzman J, Eibl MM

Abstract
Hypogammaglobulinemia (serum IgG lower than 2 SD below the age-matched mean) and clinical symptoms such as increased susceptibility to infection, autoimmune manifestations, granulomatous disease, and unexplained polyclonal lymphoproliferation are considered to be diagnostic hallmarks in patients with common variable immunodeficiency (CVID), the most frequent clinically severe primary immunodeficiency syndrome. In the present study, we investigated patients with hypogammaglobulinemia and no clinical or immunological signs of defective cell-mediated immunity and differentiated two groups on the basis of their IgG antibody formation capacity against a variety of different antigens (bacterial toxins, polysaccharide antigens, viral antigens). Patients with hypogammaglobulinemia and intact antibody production (HIAP) displayed no or only mild susceptibility to infections, while CVID patients showed marked susceptibility to bacterial infections that normalized following initiation of IVIG or subcutaneous immunoglobulin replacement therapy. There was a substantial overlap in IgG serum levels between the asymptomatic HIAP group and the CVID patients examined before immunoglobulin treatment. HIAP patients showed normal levels of switched B-memory cells (CD19(+)CD27(+)IgD(-)), while both decreased and normal levels of switched B-memory cells could be found in CVID patients. IgG antibody response to a primary antigen, tick-borne encephalitis virus (TBEV), was defective in CVID patients, thus confirming their substantial defect in IgG antibody production. Defective IgG antibody production against multiple antigens could also be demonstrated in an adult patient with recurrent infections but normal IgG levels. To facilitate early treatment before recurrent infections may lead to organ damage, the antibody formation capacity should be examined in hypogammaglobulinemic patients and the decision to treat should be based on the finding of impaired IgG antibody production.

PMID: 25699049 [PubMed]

[Hyper IgE syndrome: three case reports].

February 24, 2015 By Manish Butte

[Hyper IgE syndrome: three case reports].

Rev Chil Pediatr. 2014 Jun;85(3):328-36

Authors: Tagle C MT, Melys G A, Castillo M A, Norambuena R X, Quezada L A

Abstract
INTRODUCTION: Autosomal dominant Hyper IgE syndrome (HIES-AD) is a primary immunodeficiency associated with connective tissue, skeletal, vascular and brain disorders. The pathogenesis of immune deficiency lies in an alteration of Th17 cells which explains the special susceptibility of these patients to S. aureus and Candida infections.
OBJECTIVE: To describe three children diagnosed with hyper IgE syndrome and conduct a study on the subject, with special focus on the dominant form of the disease.
CASE REPORTS: 3 children with HIES-AD (2 males and one female) with eczema since birth, skin, ear, lung, and lymph node infections, and serum IgE levels over 2,000 IU/ml and eosinophilia values, treated with antibiotics and topically, and 7 year follow-up.
CONCLUSIONS: It is a rare condition that requires a high index of suspicion and early management of infections. One of its main diagnoses is atopic syndrome with recurrent infections but both conditions differ in context, response and resolution against infections and lack of other phenotypic characteristics.

PMID: 25697250 [PubMed – in process]

Unexpected reactions of the anti-IgA antibody particle gel immunoassay.

February 24, 2015 By Manish Butte

Unexpected reactions of the anti-IgA antibody particle gel immunoassay.

Transfus Med. 2014 Feb;24(1):55-7

Authors: Strobel E, von Meyer A

Abstract
BACKGROUND: The cause of allergic transfusion reactions remains often unknown, but in rare cases anti-immunoglobulin A (IgA) antibodies in patients with IgA-deficiency can be found. We report on the use of the DiaMed particle gel immunoassay (PaGIA) for detection of anti-IgA antibodies in patients with allergic transfusion reactions.
METHODS: The examination of the suspected adverse reactions included an anti-IgA antibody test (ID-PaGIA Anti-IgA antibody test; DiaMed GmbH, Cressier , Switzerland) and measurement of IgA concentration in the patient’s plasma. In the case of a discrepancy IgA subclasses were examined and neutralization of the anti-IgA antibodies by pure IgA was performed.
RESULTS: Of 142 patients tested for IgA concentration and anti-IgA antibodies, 8 gave positive results for the anti-IgA antibody test. In seven of these cases (4.9% of the patients tested) IgA levels were found to be normal, and in four of five so tested, the positive result could not be neutralized with purified IgA. Only one patient had confirmed IgA deficiency with anti-IgA antibodies that were neutralized by addition of purified IgA.
CONCLUSION: Cause and clinical relevance of a positive reaction of the anti-IgA antibody test in patients with normal total IgA and normal IgA subclasses remains unknown. Because of the high false positive rate we do not recommend this test as a screening test for anti-IgA antibodies when evaluating allergic transfusion reactions, but instead recommend measurement of total IgA in patient’s plasma or serum as a primary screen for IgA deficiency with antibodies as a cause of allergic transfusion reaction.

PMID: 24325384 [PubMed – indexed for MEDLINE]

Guidelines for genetic studies in single patients: lessons from primary immunodeficiencies.

February 20, 2015 By Manish Butte

Guidelines for genetic studies in single patients: lessons from primary immunodeficiencies.

J Exp Med. 2014 Oct 20;211(11):2137-49

Authors: Casanova JL, Conley ME, Seligman SJ, Abel L, Notarangelo LD

Abstract
Can genetic and clinical findings made in a single patient be considered sufficient to establish a causal relationship between genotype and phenotype? We report that up to 49 of the 232 monogenic etiologies (21%) of human primary immunodeficiencies (PIDs) were initially reported in single patients. The ability to incriminate single-gene inborn errors in immunodeficient patients results from the relative ease in validating the disease-causing role of the genotype by in-depth mechanistic studies demonstrating the structural and functional consequences of the mutations using blood samples. The candidate genotype can be causally connected to a clinical phenotype using cellular (leukocytes) or molecular (plasma) substrates. The recent advent of next generation sequencing (NGS), with whole exome and whole genome sequencing, induced pluripotent stem cell (iPSC) technology, and gene editing technologies-including in particular the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology-offer new and exciting possibilities for the genetic exploration of single patients not only in hematology and immunology but also in other fields. We propose three criteria for deciding if the clinical and experimental data suffice to establish a causal relationship based on only one case. The patient’s candidate genotype must not occur in individuals without the clinical phenotype. Experimental studies must indicate that the genetic variant impairs, destroys, or alters the expression or function of the gene product (or two genetic variants for compound heterozygosity). The causal relationship between the candidate genotype and the clinical phenotype must be confirmed via a relevant cellular phenotype, or by default via a relevant animal phenotype. When supported by satisfaction of rigorous criteria, the report of single patient-based discovery of Mendelian disorders should be encouraged, as it can provide the first step in the understanding of a group of human diseases, thereby revealing crucial pathways underlying physiological and pathological processes.

PMID: 25311508 [PubMed – indexed for MEDLINE]

Human T-lymphotropic virus type 1-infected cells secrete exosomes that contain Tax protein.

February 20, 2015 By Manish Butte

Human T-lymphotropic virus type 1-infected cells secrete exosomes that contain Tax protein.

J Biol Chem. 2014 Aug 8;289(32):22284-305

Authors: Jaworski E, Narayanan A, Van Duyne R, Shabbeer-Meyering S, Iordanskiy S, Saifuddin M, Das R, Afonso PV, Sampey GC, Chung M, Popratiloff A, Shrestha B, Sehgal M, Jain P, Vertes A, Mahieux R, Kashanchi F

Abstract
Human T-lymphotropic virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis. The HTLV-1 transactivator protein Tax controls many critical cellular pathways, including host cell DNA damage response mechanisms, cell cycle progression, and apoptosis. Extracellular vesicles called exosomes play critical roles during pathogenic viral infections as delivery vehicles for host and viral components, including proteins, mRNA, and microRNA. We hypothesized that exosomes derived from HTLV-1-infected cells contain unique host and viral proteins that may contribute to HTLV-1-induced pathogenesis. We found exosomes derived from infected cells to contain Tax protein and proinflammatory mediators as well as viral mRNA transcripts, including Tax, HBZ, and Env. Furthermore, we observed that exosomes released from HTLV-1-infected Tax-expressing cells contributed to enhanced survival of exosome-recipient cells when treated with Fas antibody. This survival was cFLIP-dependent, with Tax showing induction of NF-κB in exosome-recipient cells. Finally, IL-2-dependent CTLL-2 cells that received Tax-containing exosomes were protected from apoptosis through activation of AKT. Similar experiments with primary cultures showed protection and survival of peripheral blood mononuclear cells even in the absence of phytohemagglutinin/IL-2. Surviving cells contained more phosphorylated Rb, consistent with the role of Tax in regulation of the cell cycle. Collectively, these results suggest that exosomes may play an important role in extracellular delivery of functional HTLV-1 proteins and mRNA to recipient cells.

PMID: 24939845 [PubMed – indexed for MEDLINE]

Specific retrograde transduction of spinal motor neurons using lentiviral vectors targeted to presynaptic NMJ receptors.

February 20, 2015 By Manish Butte

Specific retrograde transduction of spinal motor neurons using lentiviral vectors targeted to presynaptic NMJ receptors.

Mol Ther. 2014 Jul;22(7):1285-98

Authors: Eleftheriadou I, Trabalza A, Ellison S, Gharun K, Mazarakis N

Abstract
To understand how receptors are involved in neuronal trafficking and to be able to utilize them for specific targeting via the peripheral route would be of great benefit. Here, we describe the generation of novel lentiviral vectors with tropism to motor neurons that were made by coexpressing onto the lentiviral surface a fusogenic glycoprotein (mutated sindbis G) and an antibody against a cell-surface receptor (Thy1.1, p75(NTR), or coxsackievirus and adenovirus receptor) on the presynaptic terminal of the neuromuscular junction. These vectors exhibit binding specificity and efficient transduction of receptor positive cell lines and primary motor neurons in vitro. Targeting of each of these receptors conferred to these vectors the capability of being transported retrogradely from the axonal tip, leading to transduction of motor neurons in vitro in compartmented microfluidic cultures. In vivo delivery of coxsackievirus and adenovirus receptor-targeted vectors in leg muscles of mice resulted in predicted patterns of motor neuron labeling in lumbar spinal cord. This opens up the clinical potential of these vectors for minimally invasive administration of central nervous system-targeted therapeutics in motor neuron diseases.

PMID: 24670531 [PubMed – indexed for MEDLINE]

CEACAM1 induces B-cell survival and is essential for protective antiviral antibody production.

February 19, 2015 By Manish Butte

CEACAM1 induces B-cell survival and is essential for protective antiviral antibody production.

Nat Commun. 2015;6:6217

Authors: Khairnar V, Duhan V, Maney SK, Honke N, Shaabani N, Pandyra AA, Seifert M, Pozdeev V, Xu HC, Sharma P, Baldin F, Marquardsen F, Merches K, Lang E, Kirschning C, Westendorf AM, Häussinger D, Lang F, Dittmer U, Küppers R, Recher M, Hardt C, Scheffrahn I, Beauchemin N, Göthert JR, Singer BB, Lang PA, Lang KS

Abstract
B cells are essential for antiviral immune defence because they produce neutralizing antibodies, present antigen and maintain the lymphoid architecture. Here we show that intrinsic signalling of CEACAM1 is essential for generating efficient B-cell responses. Although CEACAM1 exerts limited influence on the proliferation of B cells, expression of CEACAM1 induces survival of proliferating B cells via the BTK/Syk/NF-κB-axis. The absence of this signalling cascade in naive Ceacam1(-/-) mice limits the survival of B cells. During systemic infection with cytopathic vesicular stomatitis virus, Ceacam1(-/-) mice can barely induce neutralizing antibody responses and die early after infection. We find, therefore, that CEACAM1 is a crucial regulator of B-cell survival, influencing B-cell numbers and protective antiviral antibody responses.

PMID: 25692415 [PubMed – as supplied by publisher]

Epstein-Barr virus: dermatologic associations and implications: part II. Associated lymphoproliferative disorders and solid tumors.

February 19, 2015 By Manish Butte

Epstein-Barr virus: dermatologic associations and implications: part II. Associated lymphoproliferative disorders and solid tumors.

J Am Acad Dermatol. 2015 Jan;72(1):21-34; quiz 35-6

Authors: Eminger LA, Hall LD, Hesterman KS, Heymann WR

Abstract
Epstein-Barr virus (EBV) was the first human virus to be associated with oncogenesis. Over the past few decades, cumulative research has revealed that latent EBV infection may be implicated in the pathogenesis of a heterogeneous group of lymphoproliferative disorders and malignancies occurring in both immunocompetent and immunocompromised hosts. Many of these diseases have either primary or secondary cutaneous manifestations. Serologic studies and EBV-encoded RNA in situ hybridization stains have been used to show the association of EBV with disease; while these findings may imply a role, they do not equate with causation. In part II of this continuing medical education review, the salient features of EBV-associated lymphoproliferative disorders and solid tumors are detailed.

PMID: 25497918 [PubMed – indexed for MEDLINE]

Melanoma in patients with chronic lymphocytic leukemia and non-Hodgkin lymphoma.

February 19, 2015 By Manish Butte

Melanoma in patients with chronic lymphocytic leukemia and non-Hodgkin lymphoma.

J Am Acad Dermatol. 2015 Jan;72(1):78-84

Authors: Famenini S, Martires KJ, Zhou H, Xavier MF, Wu JJ

Abstract
BACKGROUND: The relationship between melanoma and chronic lymphocytic leukemia (CLL) or non-Hodgkin lymphoma (NHL) has been minimally investigated.
OBJECTIVE: The objective of this study was to examine the incidence of melanoma in patients with a history of CLL or NHL, and their associated mortality.
METHODS: Cohorts of Kaiser Permanente Southern California members with a history of CLL and NHL were identified. Age-adjusted incidence density rates of melanoma among patients with CLL or NHL were compared with rates of melanoma among the general population of Kaiser Permanente Southern California patients. The mortality of patients with melanoma was examined using Cox proportional hazards modeling.
RESULTS: The age-adjusted incidence rate per 100,000 person-years for melanoma among patients with either CLL or NHL was 107 (95% confidence interval 84.4-129.6) versus 25.9 among the general population (95% confidence interval 84.4-129.6, P < .001). Patients with melanoma and a history of CLL or NHL had 2.46 greater odds of death compared with those without CLL or NHL (95% confidence interval 1.77-3.41).
LIMITATIONS: This study was retrospective in nature; the International Classification of Diseases, Ninth Revision codes used may contain diagnostic errors; and only overall survival was used in our analysis.
CONCLUSIONS: Patients with a history of CLL or NHL have a higher incidence of melanoma. Patients with CLL or NHL who are subsequently given the diagnosis of melanoma have a higher mortality than patients with melanoma without a preceding diagnosis of CLL.

PMID: 25440434 [PubMed – indexed for MEDLINE]