Rlonocyte and polynlorphonuclcar neutrophil (I'hlN) chemotaxis was studied in cord blood fro111 healthy terrn infants. Rlonocytc chemotaxis was nor~llal to increased ( 1 15-12670) whereas PRlN che~~lotaxis was clecreasecl (79%) in comp:lrison with that of healthy atlult control subjects. Generation of chenlotactic factors fro111 cord sera was inlpairecl, being 55% of that generated by pooletl nornlal hunlan serulll (I'NIIS). Cord serunl was less inhibitory than poolecl adult hurilan scrtrni for adult tilonocytes when the cells were suspentled in 1070 serulli and testetl for chcn~otaxis. No inhibition of cherllotactic factors by either corcl or adult sera was observed. 'l'hc dissociation of cherllotactic response of the two tlifferent phagocytic cells may represent a protective ~ilecllanisril whereby one cell can corllpensatc for a clefect in the response o f the othcr.

A patient with severe combined immunodeficiency received seven transplants of bone marrow from an HLA-B-compatible and HLA-D-compatible unrelated donor in an attempt to provide immunologic reconstitution. The first four transplants achieved restricted engraftment with evidence of rudimentary immunologic function. A fifth transplant, given after low-dose cyclophosphamide, produced reconstituion of cell-mediated immunity. Marrow aplasia developed after recontamination with a nonpathogenic microflora. Transplantation of marrow previously stored in liquid nitrogen was ineffective. A subsequent transplant, administered after high-dose cyclophosphamide, achieved durable engraftment, with complete hematopoietic and immunologic reconstitution. Seventeen months after transplantation, full functional engraftment persists. Graft-versus-host disease has been chronic and moderately severe, but limited to the skin and oral mucosa. Transplantation of marrow from unrelated histocompatible donors may provide a useful treatment for patients with severe combined immunodeficiency or aplastic anemia who lack a matched sibling or related donor.

Thymic function was evaluated by quantitation of circulating thymic factor in patients with several forms of severe infantile immunodeficiency diseases. Direct quantitation of thymic factor in serum of patients with severe combined immunodeficiency revealed heterogeneity of this syndrome by this parameter, as was also shown by study of susceptibility of the marrow cells to differentiation in vitro. Thymic factor was not detectable in one patient with severe combined immunodeficiency, but was present in normal or near-normal concentrations in three others. Circulating levels of this hormonal activity were also not detectable in a patient with DiGeorge athymic syndrome. Following marrow or fetal liver transplantation, which corrected the severe combined immunodeficiency, thymic factor levels either increased slightly or did not change appreciably. Fetal thymic transplantation, which together with fetal liver transplantation corrected the immunodeficiency in one patient with severe combined immunodeficiency, was associated with increase of thymic factor to normal levels. Fetal thymus transplantation alone, which was employed to correct the immunodeficiency of DiGeorge athymic syndrome, caused an increase in thymic factor activity to normal or near normal levels in this patient.

No abstract

No abstract