Prenatal diagnosis of chronic granulomatous disease

Diagnostic assays for chronic granulomatous disease and other neutrophil disorders

Inasmuch as neutrophils are the primary cellular defense against bacterial and fungal infections, disorders that affect these white cells typically predispose individuals to severe and recurrent infections. Therefore, diagnosis of such disorders is an important first step in directing long-term treatment/care for the patient. Herein, we describe methods to identify chronic granulomatous disease, leukocyte adhesion deficiency, and neutropenia. The assays are relatively simple to perform and cost effective and can be performed with equipment available in most laboratories.

Diagnostic assays for chronic granulomatous disease and other neutrophil disorders

Inasmuch as neutrophils are the primary cellular defense against bacterial and fungal infections, disorders that affect these white cells typically predispose individuals to severe and recurrent infections. Therefore, diagnosis of such disorders is an important first step in directing long-term treatment/care for the patient. Herein, we describe methods to identify chronic granulomatous disease (CGD), leukocyte adhesion deficiency (LAD), and neutropenia. The assays are relatively simple to perform, cost-effective, and can be performed with equipment available in most laboratories.

Developmental expression of NADPH phagocytic oxidase components in mouse embryos

We wished to determine when each of the four NADPH oxidase components p22 phagocytic oxidase (phox), gp91 phox, p47 phox, p67 phox is first expressed embryologically and whether the expression pattern occurs in a consistent temporal sequence or whether the four genes are expressed simultaneously. A deficiency of any one of them results in chronic granulomatous disease (CGD). mRNA transcripts and protein expression for p22 phox, gp91 phox, p47 phox, p67 phox was monitored in murine embryos at time of implantation (E5.5) until E 11.5, and in fetal liver, spleen, and limb bone marrow from E 14 until term (E 19). We observed that mRNA was first expressed for p22 phox at E 5.5, for p67 phox at E 7.0 and for p47 phox at E 7.5 before the onset of yolk sac hematopoiesis (E 8.0). gp91 Phox mRNA was first expressed at E 9.0. However, only p22 phox protein was expressed in circulating hemocytoblast by E 9.0. No other embryonic tissue contained phox proteins either before or after the establishment of hemocytoblastic circulation. The four specific mRNA transcripts and phox proteins were expressed in nests of developing granulocytes in liver by E 14 and the expression continued in the liver at E 16 and E 19. Spleen and limb bone marrow showed inconsistent results. Cord blood neutrophils contained all phox proteins. These studies confirm that the four CGD-related phox mRNA components of NADPH oxidase are expressed early in embryonic development and the expression occurs in a consistent sequential fashion but only p22 phox protein appears in embryonic hemocytoblast.

Prenatal diagnosis of chronic granulomatous disease (CGD) in four high risk male fetuses

Prenatal diagnosis of chronic granulomatous disease (CGD) was performed in four male high risk fetuses. The male sex was previously determined by an amniotic cell karyotype. Three kinds of test were performed on fetal blood obtained by umbilical venous puncture under fetoscopy at the 20th gestational week: nitroblue tetrazolium reduction (NBT) cytochemical test with phorbol myristate acetate (PMA) as activator; luminol enhanced chemiluminescence with activation by serum opsonized zymosan (STZ) or PMA; superoxide anion (0-2) production by measurement of the superoxide dismutase inhibitable reduction of cytochrome c with PMA as activator. Results were compared to those obtained in six fetuses investigated for other inherited diseases. In one case, absence of granulocyte defects was confirmed at birth. In three other cases, the tests showed deficient metabolic oxidative granulocytes. The pregnancy was terminated and the CGD diagnosis was confirmed on the products of abortion. The use of three different techniques performed on whole blood for CGD prenatal diagnosis is recommended instead of a single isolated test to ensure a higher confidence in the diagnosis.