HY-specific T cells are presumed to play a role in acute graft-versus-host disease (aGVHD) after female-to-male stem cell transplantation (SCT). However, infiltrates of these T cells in aGVHD... Show moreHY-specific T cells are presumed to play a role in acute graft-versus-host disease (aGVHD) after female-to-male stem cell transplantation (SCT). However, infiltrates of these T cells in aGVHD-affected tissues have not yet been reported. We evaluated the application of HLA-A2/HY dextramers for the in situ detection of HY-specific T cells in cryopreserved skin biopsy specimens. We applied the HLA-A2/HY dextramers on cryopreserved skin biopsy specimens from seven male HLA-A2(+) pediatric patients who underwent stem cell transplantation with confirmed aGVHD involving the skin. The dextramers demonstrated the presence of HY-specific T cells. In skin biopsy specimens of three male recipients of female grafts, 68% to 78% of all skin-infiltrating CD8(+) T cells were HY-specific, whereas these cells were absent in biopsy specimens collected from sex-matched patient-donor pairs. Although this study involved a small and heterogeneous patient group, our results strongly support the hypothesis that HY-specific T cells are actively involved in the pathophysiology of aGVHD after sex-mismatched stem cell transplantation. Show less
IJspeert, H.; Lankester, A.C.; Berg, J.M. van den; Wiegant, W.; Zelm, M.C. van; Weemaes, C.M.R.; ... ; Burg, M. van der 2011
Artemis deficiency is known to result in classical T-B- severe combined immunodeficiency (SCID) in case of Artemis null mutations, or Omenn's syndrome in case of hypomorphic mutations in the... Show moreArtemis deficiency is known to result in classical T-B- severe combined immunodeficiency (SCID) in case of Artemis null mutations, or Omenn's syndrome in case of hypomorphic mutations in the Artemis gene. We describe two unrelated patients with a relatively mild clinical T-B- SCID phenotype, caused by different homozygous Artemis splice-site mutations. The splice-site mutations concern either dysfunction of a 5' splice-site or an intronic point mutation creating a novel 3' splice-site, resulting in mutated Artemis protein with residual activity or low levels of wild type (WT) Artemis transcripts. During the first 10 years of life, the patients suffered from recurrent infections necessitating antibiotic prophylaxis and intravenous immunoglobulins. Both mutations resulted in increased ionizing radiation sensitivity and insufficient variable, diversity and joining (V(D)J) recombination, causing B-lymphopenia and exhaustion of the naive T-cell compartment. The patient with the novel 30 splice-site had progressive granulomatous skin lesions, which disappeared after stem cell transplantation (SCT). We showed that an alternative approach to SCT can, in principle, be used in this case; an antisense oligonucleotide (AON) covering the intronic mutation restored WT Artemis transcript levels and non-homologous end-joining pathway activity in the patient fibroblasts. Genes and Immunity (2011) 12, 434-444; doi:10.1038/gene.2011.16; published online 10 March 2011 Show less
Veltrop-Duits, L.A.; Vreeswijk, T. van; Heemskerk, B.; Thijssen, J.C.P.; Seady, R. el; Zijde, E.M.J.V.D.; ... ; Schilham, M.W. 2011
Background. Human adenovirus (HAdV) infections are frequent in children after allogeneic stem cell transplantation (SCT) and may become fatal. Whether these infections occur through reactivation of... Show moreBackground. Human adenovirus (HAdV) infections are frequent in children after allogeneic stem cell transplantation (SCT) and may become fatal. Whether these infections occur through reactivation of endogenous virus or transmission via the graft remains a matter of debate. Methods. In a cohort of 24 pediatric patients who received SCT, infections with 1 or more of 5 serotypes of HAdV (1, 2, 5, 6, and 31) were detected by culture. Neutralizing antibody (NAb) titers were measured in vitro by means of a virus neutralization assay. Results. In 11 patients the infection was restricted to 1 site as demonstrated by culture only, and in 13 patients the HAdV infection was disseminated because plasma samples contained HAdV DNA. The 5 most commonly encountered HAdV serotypes caused 35 infectious episodes after SCT. Serum titers of NAb against these 5 serotypes of HAdV were measured before and after transplantation. High titers of NAb against a certain serotype in the recipient prior to SCT, reflecting previous infection, appeared to predispose for infection with the same serotype after SCT. In only 1 case of 41 independent samples of graft material, a very low level of HAdV DNA was detected. Antibody responses after SCT were detected in 21 of 35 infectious episodes. Conclusions. Together, these data suggest that adenoviral complications after SCT are caused by reactivation of endogenous persistent HAdV rather than by de novo infection from the donor or environment. This finding may offer a strategy of prophylactic treatment of high-risk patients before SCT to prevent infectious complications after allogeneic SCT. Show less
Autosomal-recessive immunodeficiency, centromeric instability, and facial anomalies (ICF) syndrome is mainly characterized by recurrent, often fatal, respiratory and gastrointestinal infections.... Show moreAutosomal-recessive immunodeficiency, centromeric instability, and facial anomalies (ICF) syndrome is mainly characterized by recurrent, often fatal, respiratory and gastrointestinal infections. About 50% of patients carry mutations in the DNA methyltransferase 3B gene (DNMT3B) (ICF1). The remaining patients carry unknown genetic defects (ICF2) but share with ICF1 patients the same immunological and epigenetic features, including hypomethylation of juxtacentromeric repeat sequences. We performed homozygosity mapping in five unrelated ICF2 patients with consanguineous parents and then performed whole-exome sequencing in one of these patients and Sanger sequencing in all to identify mutations in the zinc-finger- and BTB (bric-a-bric, tramtrack, broad complex)-domain-containing 24 (ZBTB24) gene in four consanguineously descended ICF2 patients. Additionally, we found ZBTB24 mutations in an affected sibling pair and in one patient for whom it was not known whether his parents were consanguineous. ZBTB24 belongs to a large family of transcriptional repressors that include members, such as BCL6 and PATZ1, with prominent regulatory roles in hematopoietic development and malignancy. These data thus indicate that ZBTB24 is involved in DNA methylation of juxtacentromeric DNA and in B cell development and/or B and T cell interactions. Because ZBTB24 is a putative DNA-binding protein highly expressed in the lymphoid lineage, we predict that by studying the molecular function of ZBTB24, we will improve our understanding of the molecular pathophysiology of ICF syndrome and of lymphocyte biology in general. Show less
Autosomal-recessive immunodeficiency, centromeric instability, and facial anomalies (ICE) syndrome is mainly characterized by recurrent, often fatal, respiratory and gastrointestinal infections.... Show moreAutosomal-recessive immunodeficiency, centromeric instability, and facial anomalies (ICE) syndrome is mainly characterized by recurrent, often fatal, respiratory and gastrointestinal infections. About 50% of patients carry mutations in the DNA methyltransferase 3B gene (DNMT3B) (ICF1). The remaining patients carry unknown genetic defects (1072) but share with ICF1 patients the same immunological and epigenetic features, including hypomethylation of juxtacentromeric repeat sequences. We performed homozygosity mapping in five unrelated ICF2 patients with consanguineous parents and then performed whole-exome sequencing in one of these patients and Sanger sequencing in all to identify mutations in the zinc-finger- and BTB (bric-a-bric, tramtrack, broad complex)-domain-containing 24 (ZBTB24) gene in four consanguineously descended ICF2 patients. Additionally, we found ZBTB24 mutations in an affected sibling pair and in one patient for whom it was not known whether his parents were consanguineous. ZBTB24 belongs to a large family of transcriptional repressors that include members, such as BCL6 and PATZ1, with prominent regulatory roles in hematopoietic development and malignancy. These data thus indicate that ZBTB24 is involved in DNA methylation of juxtacentromeric DNA and in B cell development and/or B and cell interactions. Because ZBTB24 is a putative DNA-binding protein highly expressed in the lymphoid lineage, we predict that by studying the molecular function of ZBTB24, we will improve our understanding of the molecular pathophysiology of ICF syndrome and of lymphocyte biology in general. Show less
In myasthenia gravis (MG), the neuromuscular transmission is impaired mainly by auto-antibodies against the acetylcholine receptor (AChR) or MuSK. In about 5% of the MG patients, however, the auto... Show moreIn myasthenia gravis (MG), the neuromuscular transmission is impaired mainly by auto-antibodies against the acetylcholine receptor (AChR) or MuSK. In about 5% of the MG patients, however, the auto-antigen is still unknown. We investigated whether these idiopathic MG patients (iMG) have auto-antibodies against ErbB proteins, which influence the AChR density at the NMJ. Our results show reduced mRNA expression levels of ErbB4 in thymus tissue of iMG patients compared to AChR-MG and non-MG patients, but we could not detect anti-ErbB antibodies in sera of iMG patients. Therefore, our results do not support a role for ErbB receptors as auto-antigens in iMG patients. (C) 2010 Elsevier B.V. All rights reserved. Show less
Suwannalai, P.; Scherer, H.U.; Woude, D. van der; Ioan-Facsinay, A.; Jol-van der Zijde, C.M.; Tol, M.J.D. van; ... ; Trouw, L.A. 2011
Objectives Anti-citrullinated protein antibodies (ACPA) are highly specific for rheumatoid arthritis (RA) and have been implicated in disease pathogenesis. Recent ongoing evidence indicates that... Show moreObjectives Anti-citrullinated protein antibodies (ACPA) are highly specific for rheumatoid arthritis (RA) and have been implicated in disease pathogenesis. Recent ongoing evidence indicates that the ACPA response broadens before precipitation of full-blown RA, as indicated by a more extensive isotype usage and an increased citrullinated epitope recognition profile. Nonetheless, the evolution of the ACPA response is still poorly understood and might intrinsically differ from the protective responses against pathogens. Methods The avidity and the avidity maturation of ACPA in relation to the avidity of antibodies against recall antigens were analysed. Results The avidity of ACPA was significantly lower than the avidity of antibodies to the recall antigens tetanus toxoid and diptheria toxoid. Moreover, ACPA did not show avidity maturation during longitudinal follow-up and ACPA avidity was also relatively low in patients who displayed extensive isotype switching. Conclusions These observations indicate that the natural evolution of ACPA differs from the development of antibodies against recall antigens. These data also indicate that ACPA avidity maturation and isotype switching are disconnected, whereby extensive isotype switching occurs in the setting of restricted avidity maturation. Intrinsic differences between the RA-specific autoantibody system and protective antibody responses against pathogens could be of relevance for designing novel B cell-targeted therapies for RA. Show less
Suwannalai, P.; Scherer, H.U.; Woude, D. van der; Ioan-Facsinay, A.; Jol-van der Zijde, C.M.; Tol, M.J.D. van; ... ; Trouw, L.A. 2011
OBJECTIVES Anti-citrullinated protein antibodies (ACPA) are highly specific for rheumatoid arthritis (RA) and have been implicated in disease pathogenesis. Recent ongoing evidence indicates that... Show moreOBJECTIVES Anti-citrullinated protein antibodies (ACPA) are highly specific for rheumatoid arthritis (RA) and have been implicated in disease pathogenesis. Recent ongoing evidence indicates that the ACPA response broadens before precipitation of full-blown RA, as indicated by a more extensive isotype usage and an increased citrullinated epitope recognition profile. Nonetheless, the evolution of the ACPA response is still poorly understood and might intrinsically differ from the protective responses against pathogens. METHODS The avidity and the avidity maturation of ACPA in relation to the avidity of antibodies against recall antigens were analysed. RESULTS The avidity of ACPA was significantly lower than the avidity of antibodies to the recall antigens tetanus toxoid and diptheria toxoid. Moreover, ACPA did not show avidity maturation during longitudinal follow-up and ACPA avidity was also relatively low in patients who displayed extensive isotype switching. CONCLUSIONS These observations indicate that the natural evolution of ACPA differs from the development of antibodies against recall antigens. These data also indicate that ACPA avidity maturation and isotype switching are disconnected, whereby extensive isotype switching occurs in the setting of restricted avidity maturation. Intrinsic differences between the RA-specific autoantibody system and protective antibody responses against pathogens could be of relevance for designing novel B cell-targeted therapies for RA. Show less
Bartelink, I.H.; Jol-van der Zijde, E.M.; Boelens, J.J.; Bredius, R.G.M.; Egberts, A.C.G.; Danhof, M.; ... ; Knibbe, C.A.J. 2011
Homozygous CD19 mutations lead to an antibody deficiency due to disruption of the CD19 complex and consequent impaired signaling by the B-cell antigen receptor. We studied the effects of... Show moreHomozygous CD19 mutations lead to an antibody deficiency due to disruption of the CD19 complex and consequent impaired signaling by the B-cell antigen receptor. We studied the effects of heterozygous CD19 mutations on peripheral B-cell development and antibody responses in a large family with multiple consanguineous marriages. Sequence analysis of 96 family members revealed 30 carriers of the CD19 mutation. Lymphocyte subset counts were not significantly different between carriers and noncarriers in three different age groups (0-10 years; 11-18 years; adults). B cells of carriers had reduced CD19 and CD21 median expression levels, and had reduced proportions of transitional (0-10 years) and CD5(+) B cells (adults). CD19 carriers did not show clinical signs of immunodeficiency; they were well capable to produce normal serum Ig levels and had normal responses to primary and booster vaccinations. The frequency of mutated V-kappa alleles was not affected. Heterozygous loss of CD19 causes some changes in the naive B-cell compartment, but overall in vivo B-cell maturation or humoral immunity is not affected. Many antibody deficiencies are not monogenetic, but likely caused by a combination of multiple genetic variations. Therefore, functional analyses of immune cell function should be carried out to show whether heterozygous mutations contribute to disease. Genes and Immunity (2010) 11, 523-530; doi:10.1038/gene.2010.22; published online 6 May 2010 Show less
Faaij, C.M.J.M.; Willemze, A.J.; Revesz, T.; Balzarolo, M.; Tensen, C.P.; Hoogeboom, M.; ... ; Annels, N.E. 2010
Chemokine receptor/ligand interactions orchestrate the migration of cells to peripheral tissues such as the skin. We analysed chemokine receptor expression by acute myeloid leukaemic (AML) cells... Show moreChemokine receptor/ligand interactions orchestrate the migration of cells to peripheral tissues such as the skin. We analysed chemokine receptor expression by acute myeloid leukaemic (AML) cells present in peripheral blood (n = 7), bone marrow (n = 6), or skin (n = 11) obtained from 15 paediatric AML patients with skin involvement and in 10 AML patients without skin involvement. High percentages of circulating CCR2(pos) AML cells were only detected in patients with extramedullary disease. Skin-residing AML cells displayed a different set of receptors in situ, namely: CCR5, CXCR4, CXCR7 and CX3CR1. These results suggest the involvement of different chemokine/chemokine receptor interactions in homing and retention of AML blasts in the skin. Pediatr Blood Cancer 2010;55:344-348. (C) 2010 Wiley-Liss, Inc. Show less
Relapse of pediatric acute lymphoblastic leukemia (ALL) remains the main cause of treatment failure after allogeneic stem cell transplantation (alloSCT). A high level of minimal residual disease ... Show moreRelapse of pediatric acute lymphoblastic leukemia (ALL) remains the main cause of treatment failure after allogeneic stem cell transplantation (alloSCT). A high level of minimal residual disease (MRD) before alloSCT has been shown to predict these relapses. Patients at risk might benefit from a preemptive alloimmune intervention. In this first prospective, MRD-guided intervention study, 48 patients were stratified according to pre-SCT MRD level. Eighteen children with MRD level >= 1 x 10(-4) were eligible for intervention, consisting of early cyclosporine A tapering followed by consecutive, incremental donor lymphocyte infusions (n = 1-4). The intervention was associated with graft versus host disease >= grade II in only 23% of patients. Event-free survival in the intervention group was 19%. However, in contrast with the usual early recurrence of leukemia, relapses were delayed up to 3 years after SCT. In addition, several relapses presented at unusual extramedullary sites suggesting that the immune intervention may have altered the pattern of leukemia recurrence. In 8 out of 11 evaluable patients, relapse was preceded by MRD recurrence (median 9 weeks, range 0-30). We conclude that in children with high-risk ALL, immunotherapy-based regimens after SCT are feasible and may need to be further intensified to achieve total eradication of residual leukemic cells. Leukemia (2010) 24, 1462-1469; doi:10.1038/leu.2010.133; published online 10 June 2010 Show less
