This review examines the role of skeletal maturity (‘bone age’, BA) assessment in clinical practice. BA is mainly used in children with the following conditions: short stature (addressed in part 1 of this review), tall stature, early or late puberty, and congenital adrenal hyperplasia (all addressed in part 2). Various manual and automatic methods of BA assessment have been developed. Healthy tall children tend to have advanced BA and healthy short children tend to have delayed BA in comparison to chronological age. Growth hormone (GH) treatment of children with GH deficiency leads to a catch-up in BA that is usually appropriate for the height of the child. Response to GH is dependent on BA delay in young children with idiopathic short stature, and GH dosage appears to affect BA acceleration. In chronic renal failure, BA is delayed until puberty but then increases due to increased sensitivity of the growth plate to sex steroids, thus further impairing adult height. The assessment of BA provides an important contribution to the diagnostic workup and management of children with short stature.

SHOX (short stature homeobox-containing gene) mutations causing haploinsufficiency have been reported in some individuals with idiopathic short stature and in many patients with Leri-Weill-dyschondrosteosis. Around 80% of SHOX mutations are complete gene deletions, whereas diverse point mutations account for the rest. The aim of this study was to estimate the prevalence of SHOX mutations in children with idiopathic short stature and to give an unbiased characterization of the haploinsufficiency phenotype of such children. We recruited 140 children (61 girls), in our clinic, with idiopathic short stature, which was defined by the presence of normal IGF-I and free T4; a normal karyotype in females; the absence of endomysium antibodies, of chronic organic, psychological, or syndromatic disease; and by the lack of clear signs of any osteodysplasia. Height, arm span, and sitting height were recorded, and subischial leg length was calculated. Two highly polymorphic microsatellite markers located around the SHOX coding region (CA-SHOX repeat and DXYS233) were PCR-amplified with fluorescent primers and separated in an automatic sequencing machine. Analysis of parental DNA was performed in the probands who had only one fragment size of each of both markers. SHOX haploinsufficiency caused by a SHOX deletion was confirmed in three probands (2%), all females, who carried a de novo deletion through loss of the paternal allele. Their auxological data revealed a significant shortening of arms and legs in the presence of a low-normal sitting height, when compared with the other 137 children tested. Therefore, the extremities-trunk ratio (sum of leg length and arm span, divided by sitting height) for total height was significantly lower in the three SHOX haploinsufficient probands, in comparison with the whole group. This observation was confirmed with the auxological data of five additional patients (four females) previously diagnosed with SHOX haploinsufficiency; all but the youngest girl had height-adjusted extremities-trunk ratios more than 1 sd below the mean. All children with SHOX haploinsufficiency exhibited at least one characteristic radiological sign of Leri-Weill-dyschondrosteosis in their left-hand radiography, namely triangularization of the distal radial epiphysis, pyramidalization of the distal carpal row, or lucency of the distal ulnar border of the radius. Our observations suggest that it is rational to limit SHOX mutation screening to children with an extremities-trunk ratio less than 1.95 + 1/2 height (m) and to add a critical judgment of the hand radiography.

Context: Adult height prediction is a common procedure in pediatric endocrinology, but it is associated with a considerable variability and bias from the bone age rating. Objective: A new method for adult height prediction is presented, based on automated bone age determination. Method: The method predicts the fraction of height left to grow from age and BoneXpert bone age. This is refined by drawing the prediction toward the population mean, or alternatively toward the height predicted from the parents’ heights. Boys’ body mass index and girls’ height at menarche can be included optionally as predictors. Participants: A total of 231 normal children from the First Zurich Longitudinal Study (1ZLS) were followed from age 5 until cessation of growth with annual x-rays of the left hand. A total of 198 normal children from the Third Zurich Longitudinal Study were used for validation. Results: The root mean square error of adult height prediction (Tanner-Whitehouse 3 method in parentheses considered as standard for accuracy) on the 1ZLS was 3.3 cm (3.5 cm) for boys aged 10–15 yr and 2.7 cm (3.1 cm; P < 0.005 for difference to Tanner-Whitehouse 3) for girls aged 8–13 yr. High body mass index before puberty negatively affected adult height of boys, independent of bone age. Conclusions: With the new method, adult height prediction has become objective because the dependence on manual bone age rating is eliminated. The method is well-suited to analyze large studies and provide a consistent body of evidence regarding the relation between maturation, body mass, and growth across populations, conditions, and ethnicities.

Summary: Positive selected haematopoietic stem cells are increasingly used for allogeneic transplantation with the CD34 antigen employed in most separation techniques. However, the recently described pentaspan molecule CD133 appears to be a marker of more primitive haematopoietic progenitors. Here we report our experience with a new CD133‐based selection method in 10 paediatric patients with matched unrelated (n = 2) or mismatched‐related donors (n = 8). These patients received a combination of stem cells (median = 29·3 × 10⁶/kg), selected with either anti‐CD34 or anti‐CD133 coated microbeads. The proportion of CD133⁺ selected cells was gradually increased from patient to patient from 10% to 100%. Comparison of CD133⁺ and CD34⁺ separation procedures revealed similar purity and recovery of target populations but a lower depletion of T cells by CD133⁺ selection (3·7 log vs. 4·1 log, P < 0·001). Both separation procedures produced >90% CD34⁺/CD133⁺ double positive target cells. Engraftment occurred in all patients (sustained primary, n = 8; after reconditioning, n = 2). No primary acute graft versus host disease (GvHD) ≥ grade II or chronic GvHD was observed. The patients showed a rapid platelet recovery (median time to independence from substitution = 13·5 d), whereas T cell regeneration was variable. Five patients are alive with a median follow‐up of 10 months. Our data demonstrates the feasibility of CD133⁺ selection for transplantation from alternative donors and encourages further trials with total CD133⁺ separated grafts.

Adenovirus infection after allogeneic hematopoietic stem cell transplantation is still causing significant morbidity and mortality, especially in children. It has been demonstrated that a sufficient host T-cell response is essential to clear the virus. Adoptive transfer of specific T-cell immunity from the donor to the recipient has become a new treatment option for patients with systemic adenoviral infection who lack specific T-cell responses. The adenoviral hexon protein was shown to be an immunodominant T-cell target. We describe here a Good Manufacturing Practice-compatible generation of hexon-specific T cells developed by isolating interferon-gamma-secreting T cells after stimulation of mononuclear cells ex vivo with hexon protein. Phenotypical and functional characterization of the generated, specific T-cell product resulted in a mixed population of CD4 and CD8-positive T cells with an intermediate effector memory phenotype. Isolated hexon-specific T cells showed high expansion potential in vitro and specific cytotoxicity. T-cell lines, directed against type 5 hexon protein showed good crossreactivity against viral strains from other adenovirus species. The availability for isolation of hexon-specific T cells among 76 hematopoietic stem cell transplantation donors showed in > 72% a sufficient T-cell response (0.05% of T cells). In conclusion, Good Manufacturing Practice-grade selection of adenovirus-specific T cells for adoptive immunotherapy by hexon-induced secretion of interferon-gamma has been established. Adoptive T-cell transfer could potentially restore T-cell immunity against adenovirus after allogeneic stem cell transplantation.