G. R. Burgio

Serum IgG subclass concentrations in healthy subjects at different age: Age normal percentile charts

IgG subclass levels were determined in 448 normal children from 6 months to 18 years of age and in 141 healthy adults by radial immunodiffusion using monoclonal antibodies. Age-normal percentile values were calculated for each year of age up to 18 years for IgG1, IgG2, IgG3 and in adults for all four subclasses. The broad spread of IgG4 values in children did not permit calculation of reference values.

Ethical reappraisal of 15 years of cord-blood transplantation

Since the first successful use of cord blood as source of haemopoietic stem cells for transplantation in 1988, more than 2000 patients with malignant or non-malignant disorders have been treated with this procedure. Collection and storage of cord blood has prompted ethical considerations, mainly dealing with the issues of autonomy in making decisions about donation of cord blood, and of privacy and confidentiality in the tests required before use of placental cells for transplantation. The ethical implications of possible storage of cord-blood cells for autologous use has also been discussed. Preimplantation selection of HLA-matched embryos to obtain a donor of cells for cord-blood transplantation of a sibling with a life-threatening disease has raised the issue of the extent to which this approach complies with the principles of bioethics.

Selective IgA deficiency: Clinical and immunological evaluation of 50 pediatric patients

Fifty children with IgA deficiency were followed for 1 to 4 years from 1975 to 1978. Thirty-five had complete deficiency of serum IgA (<2.5 IU/ml) and 15 partial deficiency (serum IgA below the 10th centile for age). Patients with another associated immunodeficiency, such as ataxia-telangiectasia, were not included. Most children with complete deficiency of IgA had recurrent respiratory and/or gastrointestinal infections, about half with onset in the first year of life, while partial deficiency of IgA has probably little if any importance for anti-infectious immunity but is important in the pathogenesis of atopy. Atopic diseases were frequent in both groups. Chromosomal abnormalities were found in 2 patients: trisomy 21 in one and in the other a ring chromosome 18. No important defects in cellular immunity were detected but some isolated, borderline abnormalities were often present.

Immunology of the neonate

Immunologic Development: Introductory Remarks.- T-Cell Development.- Humoral Immunity in the Human Neonate.- Regulation of Antibody Synthesis in the Neonate.- The Ontogeny of the Immune Response: The Role of Maternal Factors.- Mononuclear Phagocyte Function in the Perinatal Period.- Mechanisms of Abnormal Neutrophil Function in the Human Neonate: Prospects for Therapy.- Complement Function in the Neonate.- Modulation of Nonspecific Defense Mechanisms in the Neonate.- T-Cell Development and Function: Relationship to Immunodeficiencies.- Activation and Functional Capacity of Neonatal T Cells: Analysis of Interleukin-2 and Interleukin-2 Receptor Responsiveness.- Development of Lymphocyte Responses to Herpes Simplex Virus Following Neonatal Infection.- T and NK Lymphocyte Subpopulations in the Neonate.- Analysis of the Immunological Dysregulation Underlying Defective Interferon ? Secretion in the Human Neonate.- Immunity and Infections in the Neonate.- Intravenous Gammaglobulin Replacement for Prophylaxis of Infection in Preterm Neonates.- Prevention of Atopy: Neonatal Aspects.- Treatment of Infants with Severe Combined Immunodeficiency by Bone Marrow or Fetal Liver Transplantation.- Summing Up.

A comparison of secretory antibodies in breast-fed and formula-fed infants over the first six months of life

In the present study salivary IgA, anti‐Escherichia coli, anti‐β‐lactoglobulin and anti‐poliovirus type 1 IgA and IgM in serum and saliva were evaluated longitudinally in 13 breast‐fed and 14 formula‐fed infants over the first six months of life. Salivary IgA was quantified by electroimmunodiffusion; specific IgA and IgM antibodies were determined in serum and saliva by ELISA. Salivary IgA was significantly lower at age one month in breast‐fed compared with formula‐fed infants but in breast‐fed infants salivary IgA increased with age and was significantly higher at six months than at one month. In both groups of infants, at the age of six months, salivary IgA levels were significantly lower than in adult controls. No significant differences in secretory anti‐E. coli were observed between the two groups of infants. Salivary anti‐poliovirus IgA and IgM antibodies increased transiently only to disappear in most babies at age six months, while anti‐β lactoglobulin IgA and IgM, present in saliva at all ages, showed a wide scatter. No important differences in specific serum IgA or IgM antibodies were observed either between the groups or at different times within the groups.

IgG subclass deficiency in patients with Down's syndrome and aberrant hepatitis B vaccine response.

Seventeen adult patients with Downs syndrome (DS) and 19 adult healthy references were vaccinated with a hepatitis B vaccine in order to study the IgG subclass response. An enzyme‐linked immunosorbent assay (ELISA) using monoclonal antibodies specific for IgG subclasses was employed. In spite of normal levels of total IgG1 and normal or even high levels of IgG3 in the DS patients, a significantly lower IgG1 response to the vaccine was observed in trisomic patients than in the references.

Immunodeficiency in Down's syndrome: Relationship between presence of human thyroglobulin antibodies and HBsAg carrier status

The relationship between the presence of hepatitis B surface antigen (HBsAg) and antibodies to human thyroglobulin (HTgAb) has been studied in 110 subjects with Downs syndrome (DS) from 4 months to 50 years of age and in 122 controls carefully matched for sex, age and socio-environmental conditions. The overall percentage of HBsAg carriers was 22.7 in DS and 6.6 in controls and that of HTgAb-positive subjects was 41.8 in DS and 19.7 in controls. In DS the frequency of HTgAb-positive subjects was very high, even in the youngest age groups in which the percentage of HBsAg carriers was relatively low; the latter thereafter showed a marked increase with age. A positive association between the presence of HBsAg and HTgAb was found only in the oldest age group of DS subjects. It is thus concluded that in DS the high frequency of HTgAb cannot be attributed to chronic hepatitis B virus infection. On the contrary, the presence of HTgAb might well represent an early “marker” of immunodeficiency and increased susceptibility to infection with hepatitis B virus.

Antiphospholipid antibodies in paediatrics

Antiphospholipid antibodies, i.e. circulating auto-antibodies to negatively charged phospholipids, are mainly observed in patients with systemic lupus erythematosus, but may also occur in individuals who lack evidence of a well-defined systemic disease. Several studies have suggested that they may play a direct role in the pathogenesis of recurrent vascular thrombosis, repeated abortions, and thrombocytopenia (socalled antiphospholipid antibody syndrome), although the mechanism by which this occurs is still poorly understood. The management of patients with antiphospholipid antibody-related thrombosis includes anti-aggregants, anticoagulants, corticosteroids, and cytotoxic drugs, but the optimum treatment is still controversial. Here we review the test systems used to detect antiphospholipid antibodies and their significance in paediatrics.

Cell-mediated cytotoxicity in down syndrome: impairment of allogeneic mixed lymphocyte reaction, NK and NK-like activities

Peripheral blood mononuclear cells (PBMC) from 16 non-institutionalized patients with Down syndrome (DS) were studied with various monoclonal antibodies and analysed for natural killer (NK), and NK-like activity. Lymphocyte proliferation and cytotoxic T-lymphocyte (CTL) cytotoxicity generated in mixed lymphocyte culture (MLC) were also evaluated in 11 DS patients. Phenotypic characterization of PBMC from DS subjects confirms our previous findings of high numbers of CD8+ lymphocytes and HNK-1+, and CD16+ cells. Lymphocyte proliferation and CTL cytotoxicity generated in MLC were low or absent in most patients. NK activity was low in almost all DS patients, while NK-like cytotoxicity generated in MLC was normal in the majority and did not correlate with NK activity from unstimulated PBMC.

Peripheral blood 'Rosette forming lymphocytes' in Down's syndrome

La reattività alla fitoemoagglutinina e la capacità di formare «rosette» con eritrociti di montone dei linfociti di sangue periferico è risultata significativamente depressa in soggetti adulti affetti da sindrome di Down. Si può ritenere che la funzione timo-dipendente vada incontro in questi pazienti ad un deterioramento assai più rapido che nella popolazione generale.