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The authors characterize BK virus–specific cellular and humoral immunity in immunocompetent controls across a wide age range and in renal transplant recipients, and show that the level of immunity reflects phases of active viral replication either after primary infection in childhood or during reactivation after transplantation.

BK polyomavirus (BKPyV) infection is widespread and typically asymptomatic during childhood, but may cause nephropathy in kidney transplant recipients. However, there is only limited knowledge on BKPyV-specific immunity in children and adults, and its role in BKPyV-replication and disease posttransplant. We therefore characterized BKPyV-specific immunity from 122 immunocompetent individuals (1–84 years), 38 adult kidney recipients with (n = 14) and without BKPyV-associated complications (n = 24), and 25 hemodialysis (HD) patients. Blood samples were stimulated with overlapping peptides of BKPyV large-T antigen and VP1 followed by flow-cytometric analysis of activated CD4 T cells expressing interferon-γ, IL-2 and tumor necrosis factor-α. Antibody-levels were determined using enzyme-linked immunosorbent assay. Both BKPyV-IgG levels and BKPyV-specific CD4 T cell frequencies were age-dependent (p = 0.0059) with maximum levels between 20 and 30 years (0.042%, interquartile range 0.05%). Transplant recipients showed a significantly higher BKPyV-specific T cell prevalence (57.9%) compared to age-matched controls (21.7%) or HD patients (28%, p = 0.017). Clinically relevant BKPyV-replication was associated with elevated frequencies of BKPyV-specific T cells (p = 0.0002), but decreased percentage of cells expressing multiple cytokines (p = 0.009). In conclusion, BKPyV-specific cellular immunity reflects phases of active BKPyV-replication either after primary infection in childhood or during reactivation after transplantation. Combined analysis of BKPyV-specific T cell functionality and viral loads may improve individual risk assessment.

Introduction: Irradiation of brain tumors (BT) in children can lead to the loss of pituitary function, predominantly manifesting as deficiencies in GH and ACTH. Objective: To assess the incidence and nature of pituitary deficiency in relation to initial tumor location in children after radiotherapy of BT. Methods: Twenty survivors (16 males and 4 females) of radiation-treated BT aged 1.4–10.9 (median 3.6) yr at diagnosis were studied, 10 with supratentorial and 10 with infratentorial BT. Radiation doses to the hypothalamus-pituitary (HP) area ranged from 30 to 54 (median 45) Gray. Follow-up was 9.4–16.9 (median 12.2) yr. Basal pituitary hormone levels were measured every 6 months. When growth failure became evident or pituitary deficiency was suspected, provocation tests of the HP axis were performed to assess GH, ACTH, and TSH function. Results: GH deficiency (GHD) developed in 17/20 (85%) children. In 10 patients, it occurred 4 yr after radiotherapy and in 2, 11 and 12 yr after radiotherapy. Six (30%) patients developed secondary hypothyroidism and 4 (20%) developed ACTH deficiency. Precocious puberty occurred in 2 girls. The course of development and the severity of hormone deficiencies were similar for supratentorial and infratentorial tumors. Conclusion: The major hormonal effect of BT irradiation in children is GHD, which may sometimes take more than 10 yr to manifest. We confirm findings by others that ACTH insufficiency occurs less frequently in children than reported for adults. Tumor location has no prognostic significance regarding the loss of HP function.

Summary Quantitative determinations of platelet aggregation were made by a modified version of the Wu-Hoak-method in venous blood samples from ten healthy volunteers. It was demonstrated that the extent to which aggregates are formed depends on the rate of flow in the needle and on other methodical influences as well as on the platelet count. Accordingly, no definite conclusions concerning aggregation conditions in vivo can be drawn from the results obtained with venous blood samples.

Summary Quantitative measurements of platelet aggregation in samples of venous blood were made in altogether 66 healthy volunteers by a modified version of the method of Wu and Hoak. The formation of aggregates was found to be unaffected or at the most barely affected by such factors as sex, age, smoking, fatty food, physical exertion and medication with isoprenaline or ovulation inhibitors. No difference in the number of aggregates formed was noted between 12 control patients and 16 patients with myocardial infarcts or 14 with other conditions predisposing to arterial thrombosis. Anticoagulant therapy had no effect on aggregation. It is suspected that aggregation in vitro due to methodological factors may obscure any quantitative alterations in the formation of aggregation present in vivo.

Pays tribute to the late Henry Fillmore, whose musical career was divided into two periods of productivity: his time in Cincinnati, Ohio, where he learned and polished his skills in publishing, merchandising, performing, and conducting, and his retirement years, when he moved to Miami and worked with community bands and the University of Miami bands.