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Activated human B cells induce inflammatory fibroblasts with cartilage-destructive properties and become functionally suppressed in return.

May 20, 2015 By Manish Butte

Activated human B cells induce inflammatory fibroblasts with cartilage-destructive properties and become functionally suppressed in return.

Ann Rheum Dis. 2015 May 18;

Authors: Störch H, Zimmermann B, Resch B, Tykocinski LO, Moradi B, Horn P, Kaya Z, Blank N, Rehart S, Thomsen M, Lorenz HM, Neumann E, Tretter T

Abstract
BACKGROUND: Cross-talk between synovial fibroblasts (SF) and immune cells is suggested to play a crucial role in inflammation and chronification of rheumatoid arthritis (RA). The contribution of B cells in this process is poorly defined.
METHODS: Here, primary B cells from healthy donors were polyclonally activated and cocultured with SF of non-synovitic origin from patients with osteoarthritis.
RESULTS: In B-SF cocultures the concentrations of interleukin 6 (IL-6) and IL-8 increased manifold compared with single cultures even under physical separation and remained stable for several days after B-cell removal. Intracellular staining confirmed SF as key producers of IL-6 and IL-8, and B cells as main producers of tumour necrosis factor alpha (TNFα) and IL-1ß. Blocking experiments with a combination of anti-TNFα-antibodies and rIL-1RA significantly reduced SF cytokine production by up to 90%, suggesting that B-cell-derived TNFα and IL-1ß were crucial mediators of SF activation. Interestingly, B-cell cytokine production, CD25 expression and proliferation decreased in cocultures by at least 50%, demonstrating a negative regulatory loop towards the activated B cells. Inhibition of activin receptor-like kinase 5, a crucial component of the tumour growth factor ß (TGFß) signalling pathway, partly restored B-cell proliferation, suggesting a contribution of SF-derived TGFß in B-cell suppression. Besides cytokines, B-cell-activated SF also upregulated secretion of matrix metalloproteases such as MMP-3, thereby acquiring potential tissue destructive properties. This was confirmed by their invasion into human cartilage in the severe combined immunodeficiency mouse fibroblast invasion model in vivo.
CONCLUSIONS: Interaction with activated B cells leads to conversion of non-arthritic SF into SF with a proinflammatory and aggressive RA-like phenotype, thereby suggesting a new, so far unrecognised role for B cells in RA pathogenesis.

PMID: 25985971 [PubMed – as supplied by publisher]

Factors influencing success of clinical genome sequencing across a broad spectrum of disorders.

May 20, 2015 By Manish Butte

Factors influencing success of clinical genome sequencing across a broad spectrum of disorders.

Nat Genet. 2015 May 18;

Authors: Taylor JC, Martin HC, Lise S, Broxholme J, Cazier JB, Rimmer A, Kanapin A, Lunter G, Fiddy S, Allan C, Aricescu AR, Attar M, Babbs C, Becq J, Beeson D, Bento C, Bignell P, Blair E, Buckle VJ, Bull K, Cais O, Cario H, Chapel H, Copley RR, Cornall R, Craft J, Dahan K, Davenport EE, Dendrou C, Devuyst O, Fenwick AL, Flint J, Fugger L, Gilbert RD, Goriely A, Green A, Greger IH, Grocock R, Gruszczyk AV, Hastings R, Hatton E, Higgs D, Hill A, Holmes C, Howard M, Hughes L, Humburg P, Johnson D, Karpe F, Kingsbury Z, Kini U, Knight JC, Krohn J, Lamble S, Langman C, Lonie L, Luck J, McCarthy D, McGowan SJ, McMullin MF, Miller KA, Murray L, Németh AH, Nesbit MA, Nutt D, Ormondroyd E, Oturai AB, Pagnamenta A, Patel SY, Percy M, Petousi N, Piazza P, Piret SE, Polanco-Echeverry G, Popitsch N, Powrie F, Pugh C, Quek L, Robbins PA, Robson K, Russo A, Sahgal N, van Schouwenburg PA, Schuh A, Silverman E, Simmons A, Sørensen PS, Sweeney E, Taylor J, Thakker RV, Tomlinson I, Trebes A, Twigg SR, Uhlig HH, Vyas P, Vyse T, Wall SA, Watkins H, Whyte MP, Witty L, Wright B, Yau C, Buck D, Humphray S, Ratcliffe PJ, Bell JI, Wilkie AO, Bentley D, Donnelly P, McVean G

Abstract
To assess factors influencing the success of whole-genome sequencing for mainstream clinical diagnosis, we sequenced 217 individuals from 156 independent cases or families across a broad spectrum of disorders in whom previous screening had identified no pathogenic variants. We quantified the number of candidate variants identified using different strategies for variant calling, filtering, annotation and prioritization. We found that jointly calling variants across samples, filtering against both local and external databases, deploying multiple annotation tools and using familial transmission above biological plausibility contributed to accuracy. Overall, we identified disease-causing variants in 21% of cases, with the proportion increasing to 34% (23/68) for mendelian disorders and 57% (8/14) in family trios. We also discovered 32 potentially clinically actionable variants in 18 genes unrelated to the referral disorder, although only 4 were ultimately considered reportable. Our results demonstrate the value of genome sequencing for routine clinical diagnosis but also highlight many outstanding challenges.

PMID: 25985138 [PubMed – as supplied by publisher]

Clinical application of whole-genome sequencing in patients with primary immunodeficiency.

May 20, 2015 By Manish Butte

Clinical application of whole-genome sequencing in patients with primary immunodeficiency.

J Allergy Clin Immunol. 2015 May 13;

Authors: Mousallem T, Urban TJ, McSweeney KM, Kleinstein SE, Zhu M, Adeli M, Parrott RE, Roberts JL, Krueger B, Buckley RH, Goldstein DB

PMID: 25981738 [PubMed – as supplied by publisher]

Primary Immunodeficiencies with Elevated IgE.

May 15, 2015 By Manish Butte

Primary Immunodeficiencies with Elevated IgE.

Int Rev Immunol. 2015 May 13;

Authors: Mogensen TH

Abstract
In recent years a number of primary immunodeficiencies (PIDs) characterized by elevated Immunoglobulin E (IgE) levels have been uncovered and termed as Hyper-IgE syndrome (HIES). In addition to the elevated levels of IgE, patients with these PIDs display a spectrum of infections by staphylococci and fungi, and in some cases viruses, particularly affecting skin and lungs. Most of these PIDs also have a non-infectious phenotype, comprising musculoskeletal, vascular, and neurological abnormalities. The genetic basis for the majority of conditions with elevated IgE has now been established and includes mutations in STAT3, DOCK8, TYK2, and most recently PGM3 molecules. However, in some patients with the relevant phenotype, mutations in these molecules are not identified, suggesting additional genetic etiologies of HIES not yet discovered. As the immunological and molecular basis of HIES is being unraveled, important insights are emerging that may have implications for our understanding of basic principles of immunology and protective immunity as well as for the pathogenesis and clinical management of patients with these complex and challenging PIDs. In this review, are presented the current knowledge on the clinical presentation, infectious phenotype, and the genetic and immunological pathogenesis of hyper-IgE syndromes as well as some other PIDs with elevated levels of IgE.

PMID: 25970001 [PubMed – as supplied by publisher]

Clinical Immunogenicity of rHuPH20, a Hyaluronidase Enabling Subcutaneous Drug Administration.

May 15, 2015 By Manish Butte

Clinical Immunogenicity of rHuPH20, a Hyaluronidase Enabling Subcutaneous Drug Administration.

AAPS J. 2015 May 13;

Authors: Rosengren S, Dychter SS, Printz MA, Huang L, Schiff RI, Schwarz HP, McVey JK, Drake FH, Maneval DC, Kennard DA, Frost GI, Sugarman BJ, Muchmore DB

Abstract
Recombinant human PH20 hyaluronidase (rHuPH20) is used to facilitate dispersion of subcutaneously delivered fluids and drugs. This report summarizes rHuPH20 immunogenicity findings from clinical trials where rHuPH20 was co-administered with SC human immunoglobulin, trastuzumab, rituximab, or insulin. Plasma samples were obtained from evaluable subjects participating in ten different clinical trials as well as from healthy plasma donors. A bridging immunoassay and a modified hyaluronidase activity assay were used to determine rHuPH20-reactive antibody titers and neutralizing antibodies, respectively. rHuPH20-binding antibody populations from selected subjects with positive titers were affinity-purified and subjected to further characterization such as cross-reactivity with endogenous PH20. Among individual trials, the prevalence of pre-existing rHuPH20-reactive antibodies varied between 3 and 12%, excepting the primary immunodeficiency (PID) studies. Incidence of treatment-induced rHuPH20 antibodies was 2 to 18%, with the highest titers (81,920) observed in PID. No neutralizing antibodies were observed. Within most trials, the kinetics of antibody responses were comparable between pre-existing and treatment-induced antibody responses, although responses classified as persistent were more common in subjects with pre-existing titers. There was no association between antibody positivity and either local or systemic adverse events. Pre-existing and treatment-induced antibody populations were of similar immunoglobulin isotypes and cross-reacted to endogenous PH20 to similar extents. No cross-reactivity to PH20 paralogs was detected. rHuPH20 induces only modest immunogenicity which has no association with adverse events. In addition, antibodies purified from baseline-positive individuals are qualitatively similar to those purified from individuals developing rHuPH20-reactive antibodies following exposure to the enzyme.

PMID: 25967925 [PubMed – as supplied by publisher]

A Clinical and Laboratory Approach to the Evaluation of Innate Immunity in Pediatric CVID Patients.

May 13, 2015 By Manish Butte

A Clinical and Laboratory Approach to the Evaluation of Innate Immunity in Pediatric CVID Patients.

Front Immunol. 2015;6:145

Authors: Kutukculer N, Azarsiz E, Karaca NE, Ulusoy E, Koturoglu G, Aksu G

Abstract
Defective adaptive immune responses are well studied in common variable immunodeficiency (CVID) patients; however, more focus is needed on innate immune system defects to explain CVID’s clinical and laboratory heterogeneity. This is the first study comparing migratory function of granulocytes, oxidative burst activity of phagocytic cells, surface integrin expressions on neutrophils and lymphocytes, natural killer (NK) cell numbers and cytotoxic activity, natural killer T cells, lymphocyte subsets such as CD8(+)CD28(+), CD4(+)CTLA-4(+) cells in CVID patients (n: 20) and healthy controls (n: 26). The relationship between laboratory findings and some clinical was also investigated. CD3(+)CD8(+) T cytotoxic cells were found to be elevated in CVID patients, but CD3(+)CD8(+)CD28(+) or CD3(+)CD8(+)CD28(-) cells did not show any significant difference. CD4(+)CTLA-4(+) cell percentages were significantly lower in CVID patients compared to healthy controls. Severe CVID patients had decreased percentages of NK cells with increased NK cell cytotoxicity suggesting possibly increased activation. Furthermore, CD3(-)CD16(+)CD56(+)CD28(+) cells of CVID patients were elevated while percentage of CD28(-) NK cells was decreased. Neutrophil migration percentages were lower but and oxidative burst activity was not affected. CD11a expressions on these cells were depressed in contrast to increased expression of CD18. Innate immunity defects may affect the extent of recurrence and severity of infections in CVID. Our observations highlight some of these associations and indicate the need for further similar studies for improving better innate system evaluation batteries for these patients. Further phenotypic correlations of these analyses will help clinicians reach a more definitive target for the molecular genetic diagnostic of pediatric CVID patients.

PMID: 25964782 [PubMed]

Early-onset hypogammaglobulinemia: A survey of 44 patients.

May 12, 2015 By Manish Butte

Early-onset hypogammaglobulinemia: A survey of 44 patients.

J Allergy Clin Immunol. 2015 May 8;

Authors: Brignier AC, Mahlaoui N, Reimann C, Picard C, Kracker S, de Vergnes N, Rieux-Laucat F, Frange P, Suarez F, Neven B, Masseau A, Aladjidi N, Donadieu J, Corby A, Bienvenu B, Cony-Makhoul P, Fischer A, Cavazzana M, Durandy A

PMID: 25959671 [PubMed – as supplied by publisher]

The intersection of immune deficiency and autoimmunity.

May 12, 2015 By Manish Butte

The intersection of immune deficiency and autoimmunity.

Curr Opin Rheumatol. 2014 Sep;26(5):570-8

Authors: Maggadottir SM, Sullivan KE

Abstract
PURPOSE OF REVIEW: Immune deficiency and autoimmunity have been recognized as cotravelers for decades. This clinically oriented review brings together our evolving mechanistic understanding to highlight associations of particular relevance to rheumatologists.
RECENT FINDINGS: Conceptually, all autoimmunity derives from a loss of tolerance. This distinguishes it from autoinflammation in which the innate immune system is dysregulated without necessarily affecting tolerance. Studies have demonstrated the profound effects of signaling defects, apoptotic pathways and the ramifications of homeostatic proliferation on tolerance. This foundation has translated into an improved understanding of the specific associations of autoimmune diseases with immune deficiencies. This important foundation paves the way for personalized treatment strategies.
SUMMARY: This review identifies critical mechanisms important to conceptualize the association of primary immune deficiencies and autoimmunity. It highlights a growing appreciation of the hidden single gene defects affecting T-cells within the group of patients with early-onset pleomorphic autoimmunity.

PMID: 25014038 [PubMed – indexed for MEDLINE]

Immunoglobulin deficiency in patients with Streptococcus pneumoniae or Haemophilus influenzae invasive infections.

May 12, 2015 By Manish Butte

Immunoglobulin deficiency in patients with Streptococcus pneumoniae or Haemophilus influenzae invasive infections.

Int J Infect Dis. 2014 Feb;19:79-84

Authors: Martinot M, Oswald L, Parisi E, Etienne E, Argy N, Grawey I, De Briel D, Zadeh MM, Federici L, Blaison G, Koebel C, Jaulhac B, Hansmann Y, Christmann D

Abstract
OBJECTIVES: Immunoglobulin (Ig) deficiency is a well-known risk factor for Streptococcus pneumoniae or Haemophilus influenzae infections and noteworthy invasive diseases. However, the proportion of these deficiencies in cases of invasive disease is unknown. The objective of this study was to evaluate the rate of Ig deficiency in cases of invasive disease.
METHODS: A prospective study was conducted from January 2008 to October 2010 in two French hospitals. Measurement of Ig levels was carried out in patients hospitalized for invasive diseases.
RESULTS: A total of 119 patients were enrolled in the study, with nine cases of H. influenzae and 110 cases of S. pneumoniae invasive disease. There were 18 cases of meningitis, 79 of invasive pneumonia, and 22 other invasive diseases. Forty-five patients (37.8%) had an Ig abnormality, 37 of whom had an Ig deficiency (20 IgG <6g/l, four isolated IgA <0.7g/l, and 13 isolated IgM <0.5g/l), while eight had an elevated monoclonal paraprotein. Nineteen of these 45 patients had a clearly defined Ig abnormality, with five primary deficiencies (three common variable immunodeficiencies and two complete IgA deficiencies) and 14 secondary deficiencies, mainly lymphoproliferative disorders. All these deficiencies were either not known or not substituted.
CONCLUSIONS: Humoral deficiency is frequent in patients with S. pneumoniae or H. influenzae invasive disease and Ig dosage should be proposed systematically after such infections.

PMID: 24326288 [PubMed – indexed for MEDLINE]

Skin microbiome imbalance in patients with STAT1/STAT3 defects impairs innate host defense responses.

May 12, 2015 By Manish Butte

Skin microbiome imbalance in patients with STAT1/STAT3 defects impairs innate host defense responses.

J Innate Immun. 2014;6(3):253-62

Authors: Smeekens SP, Huttenhower C, Riza A, van de Veerdonk FL, Zeeuwen PL, Schalkwijk J, van der Meer JW, Xavier RJ, Netea MG, Gevers D

Abstract
BACKGROUND: Chronic mucocutaneous candidiasis (CMC) and hyper-IgE syndrome (HIES) are primary immunodeficiencies mainly caused by mutations in STAT1 and STAT3, respectively. CMC and HIES patients have an increased risk for skin and mucosal infections with fungal pathogens and Staphylococcus aureus. However, it is unknown whether the genetic defects in these patients also affect the skin and mucosal microbiome, which in turn may influence host defense mechanisms.
METHODS: The skin and oral microbiome of CMC and HIES patients was compared to that of healthy controls at five body sites using 16S rRNA sequencing. The influence of skin colonizers on the immune response was investigated using in vitro experiments.
RESULTS: The microbiome of CMC and HIES patients contained more Gram-negative bacteria, especially Acinetobacter spp., and less of the normal Corynebacterium spp. compared to healthy controls. Exposure of human primary leukocytes to Acinetobacter suppressed the cytokine response to Candida albicans and S. aureus, while the normal corynebacteria did not suppress cytokine responses.
DISCUSSION: These results demonstrate that central mediators of immune responses like STAT1 and STAT3 not only directly influence immune responses, but also result in changes in the skin microbiome that in turn can amplify the defective immune response against fungal and microbial pathogens.

PMID: 23796786 [PubMed – indexed for MEDLINE]