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Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) induces proliferation and differentiation of hematopoietic stem cells. Additionally, rhGM-CSF enhances the physiologic responses of adult polymorphonuclear leukocytes (PMN) especially with respect to oxidative metabolism and chemotaxis. Neonatal PMN are deficient in chemotaxis and have been demonstrated to have reduced oxidative responses in times of stress. We evaluated the priming effects of rhGM-CSF (1-100 pmol/L) on cord (neonatal) superoxide production and chemotaxis. Cord and adult PMN were incubated with 100 pmol/L rhGM-CSF (Amgen, 4 x 10(7) U/mg) for 0-120 min and stimulated with N-formyl-l-methionyl-l-leucyl-phenylalanine. RhGM-CSF enhanced O2- production at all time periods with maximal priming at 60 min (147.97 +/- 11.14% p less than or equal to 0.006) with less, but significant enhancement at 120 min (116.53 +/- 7.92% p less than or equal to 0.05). Maximal adult PMN O2- release occurred at 120 min (190.02 +/- 8.71% p less than or equal to 0.003) and was more pronounced than cord PMN.(ABSTRACT TRUNCATED AT 250 WORDS)

The laboratory and clinical experience of a single institution of 75 consecutive children undergoing bone marrow harvesting, 65 for subsequent autologous reinfusion and 10 for allogeneic infusion, was analysed and compared in detail with the adult literature. The median age was 9.3 years (range 6 months-20 years) with equal distribution between all childhood age groups. The median volume of marrow harvested was 15.94 ml/kg (range 4.94-27.7 ml/kg) and there was no significant difference within each age group. Fifty percent of autologous marrows (32/65) required Ficoll-Hypaque density separation and the other 50% (33/65) were separated by using the Cobe 2991 cell separator. Allogeneic harvests yielded 5.1 x 10(8) cells/kg vs 2.4 x 10(8) cells/kg for autologous harvests. Only 48% of children required red cell transfusions following this procedure (average volume 9.36 ml/kg). There were no episodes of postoperative fever or infection. There was only one episode of life-threatening morbidity (1.3%), a pulmonary embolus related to venous stasis from tumor obstruction. Lastly, the average time to engraftment following autologous reinfusion (n = 10) (neutrophils greater than or equal to greater than or equal to 500 x 10(6)/l for 2 days) was 19.8 +/- 5.3 (SD) days and time to platelet recovery (greater than or equal to 20 x 10(8)/l without transfusions) was 25.6 +/- 5.8 days. This study suggests that bone marrow harvesting in a large cohort of children with an active pediatric malignancy for a future autologous bone marrow transplantation is a safe and reliable procedure with a low incidence of serious morbidity.

The presence of neonatal (cord) lymphokine-activated killer (LAK) cell activity toward natural killer cell resistant Raji and Daudi cell lines has recently been reported from our laboratory. We investigated the future therapeutic use of LAK adoptive immunotherapy by examining LAK in vitro cytotoxicity from both neonatal and adult mononuclear cells against solid tumor cell lines of relevance to pediatric oncology: SH-SY5Y (neuroblastoma), SK-NM-C (neuroblastoma-neuroepithelioma), NEP-1 (Wilms' tumor), SK-ES-1 (Ewing's sarcoma), and A-204 (rhabdomyosarcoma). Cord and adult mononuclear cells were activated by recombinant IL-2 (100 mu/ml) for 5-7 days and added in an effector:target ratio of 40:1 to 51Cr-labeled target cells. Specific cell lysis was determined after a 4-h incubation. There was a significantly high level of cord and adult LAK cytotoxicity against Wilms' (76.4 +/- 9.8 versus 77.3 +/- 6.8%) and Ewing's (84.2 +/- 5.5 versus 71.1 +/- 6.5%) cell lines and significant but moderate LAK activity against neuroepithelioma (52.0 +/- 6.6 versus 55.4 +/- 4.5%) and rhabdomyosarcoma (46.6 +/- 5.7 versus 43.9 +/- 5.2%) cell lines. There was no difference between cord and adult LAK activity toward these targets. However, a differential response toward the more classical neuroblastoma cell line, SH-SY5Y, was noted with significantly more LAK cytotoxicity from cord mononuclear cells than adult mononuclear cells (51.2 +/- 6.9 versus 28.5 +/- 8.2%) (p less than or equal to 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Chediak-Higashi Syndrome (CHS) has been associated with recurrent bacterial infections and defective polymorphonuclear (PMN) leukocyte function. Confirmation of the diagnosis of CHS and defective PMN function was established in a 2-month-old with accelerated phase CHS. The diagnosis was confirmed by demonstrating reduced PMN degranulation (beta-glucuronidase release 34.1 +/- 0.9% versus 5.1 +/- 4% and lysozyme release 17.6 +/- 1.2% versus 11.1 +/- 7% (control versus CHS) and staphylococcal bacterial killing at 15' 51.4 +/- 3.6% versus 24.9 +/- .4% (control versus CHS). Additional studies using fluorescent cytometric analysis were made to investigate other etiologies of PMN dysfunction in CHS. Total cell density and PMN granularity, as measured by fluorescent-activated cell sorter side scatter analysis, was no different from CHS and age-matched controls. Although CHS is characterized by large PMN granular inclusions, right angle light scatter analysis in this study suggests that the total cell density within the PMN of patients with CHS is normal (D less than .01). PMN granular release of surface receptors was also studied using antibody binding and fluorescent analysis. OKM1 antibody-binding demonstrated significantly reduced C3bi (MO-1) receptor expression (13% of control) p less than 0.001. Decreased surface reception expression of C3bi receptors may play an additional role in defective PMN mobility, chemotaxis, and bactericidal activity in patients with CHS.