The severe combined immunodeficient-human peripheral blood stem cell (SCID-huPBSC) mouse: a xenotransplant model for huPBSC-initiated hematopoiesis

Mononuclear cells (MNCs) containing peripheral blood stem cells (PBSCs) were obtained from solid-tumor patients undergoing mobilizing chemotherapy followed by granulocyte colony-stimulating factor for PBSC transplantation-supported dose-intensified anticancer chemotherapy and were transplanted into unconditioned "nonleaky" young severe combined immunodeficient mice. Multilineage engraftment was shown by flow cytometry and immunocytochemistry using monoclonal antibodies to various human cell surface antigens as well as identification of human immunoglobulin in murine sera. Within a dose range of MNCs suitable for transplantation (10 to 36 x 10(6) cells/graft) the number of CD34+ cells injected (optimal at > 0.7 x 10(6)/graft) determined the yield of human cells produced in recipient animals. Engraftment of hu PBSC preparations resulted in prolonged generation of physiologic levels of human cytokines including interleukin-3 (IL-3), IL-6, and granulocyte- macrophage colony-stimulating factor, which were detectable in the murine blood over a period of at least 4 months. In vivo survival of immature human progenitor cells was preserved even 9 months after transplantation. Because human IL-3 is known to stimulate early hematopoiesis, a rat fibroblast cell line was stably transfected with a retroviral vector carrying the human IL-3 gene and cotransplanted subcutaneously as additional source of growth factor. Cotransplants of this cell line producing sustained in vivo levels of circulating human IL-3 for at least 12 weeks significantly accelerated the process of engraftment of huPBSC and spurred the spread of mature human cells to the murine spleen, liver, thymus, and peripheral blood. Cotransplants of allogeneic human bone marrow stromal cells derived from long-term cultures resulted in a comparable--though less prominent--support of engraftment.     

B-cell growth factor receptor expression and B-cell growth factor response of leukemic B cell precursors and B lineage lymphoid progenitor cells

The purpose of this study was to analyze the expression of B cell growth factor (BCGF) receptors and to elucidate the biologic effects of biochemically purified natural BCGF at the B cell precursor stage of human B lineage lymphoid differentiation. The specific binding of radioiodinated high-mol-wt BCGF (125I-HMW-BCGF) and low-molecular-wt BCGF (125I-LMW-BCGF) to fresh marrow blasts from B cell precursor acute lymphoblastic leukemia (ALL) patients was initially investigated. The estimated number of radioiodinated BCGF molecules bound per blast ranged from undetectable to 24.3 X 10(3) for HMW-BCGF, and from 11.5 X 10(3) to 457.8 X 10(3) for LMW-BCGF. In 3H-TdR incorporation assays, 75% of cases showed a significant response to LMW-BCGF with a median stimulation index of 9.3. By comparison, only 33% of cases showed a significant response to HMW-BCGF with a median stimulation index of 2.4. Subsequently, B cell precursor colony assays were performed to assess and compare the biologic effects of BCGF on leukemic B lineage lymphoid progenitor cells. Among 28 cases studied, 57% responded to both HMW-BCGF and LMW-BCGF, 21% responded only to LMW-BCGF, and the remaining cases showed no proliferative response to either growth factor. The response patterns of virtually pure populations of FACS- sorted leukemic B cell precursors were essentially identical to the proliferative responses of unsorted leukemic B-cell precursors. Synergistic effects between HMW-BCGF and LMW-BCGF were observed in 80% of the cases that responded to both. The numbers of cell-bound radioiodinated BCGF molecules, the stimulation indices, as well as the number of B cell precursor colonies in BCGF-stimulated cultures showed a marked interpatient variation. Patients with structural chromosomal abnormalities (SCAs) involving 12p11-13 or patients with a Philadelphia chromosome showed a greater HMW-BCGF response at the level of leukemic progenitor cells than did other patients (P = .02). The LMW-BCGF response was significantly greater for patients with SCA than for patients without SCA (P = .04). The response of leukemic progenitor cells to HMW-BCGF or LMW-BCGF did not correlate with sex, age, disease status, FAB morphology, WBC at diagnosis, or immunophenotype. To our knowledge, this study represents the first detailed analyses of BCGF receptor expression and BCGF effects in B cell precursor ALL. The data presented provide direct evidence for the expression of functional receptors for both HMW-BCGF and LMW-BCGF in B cell precursor ALL.     

Alagille's syndrome associated with cystic renal disease

Although renal abnormalities have been described in children with Alagille's syndrome, cystic kidney disease has not often been documented, and then usually only at necropsy. Three children with Alagille's syndrome are described, in two of whom a unilateral multicystic dysplastic kidney was detected by prenatal ultrasound; in the other, a solitary cortical cyst was found later in childhood. All have normal renal function, growth, and liver synthetic function but continue to have clinical and biochemical signs of cholestasis. These cases show that unilateral cystic kidney disease with or without renal dysplasia may be associated with Alagille's syndrome, that the clinical course is not necessarily unfavourable, and that Alagille's syndrome should be included in the differential diagnosis of cystic kidney disorders associated with cholestatic liver disease. Patients with Alagille's syndrome should be evaluated by renal ultrasound.     

Delirium Tremens

The varied clinical manifestations and management of 14 male patients with delirium tremens (DT) have been studied. Eight patients were initially hospitalised for diseases unrelated to ethanol abuse i.e. 2 each for gun shot wound, myocardial infarction and stroke, and one each for pneumonia and gastroenteritis. One patient was going through withdrawal because of prodrome of viral hepatitis before he was hospitalised for uncontrolled agitation and delirium. Two known cases of mild essential hypertension on dietary therapy reported for agitation, abnormal behaviour, a single episode of tonic clonic seizure and hypertensive encephalopathy as they could not/did not get alcohol for 3 days. Three patients presented denovo with DT without concomitant illness. The other features besides delirium and hallucinations were tremulousness in 10, tachycardia in 12, fever in 3, diaphoresis in 2 and tonic clonic seizures in 4 patients. The symptoms fluctuated markedly at short intervals and 2 patients did not have any features of sympathetic overactivity. Altered hepatic biochemical parameters and ketonuria with normal blood sugar were noted in 4 and one patients respectively. Other biochemical parameters including serum electrolytes were normal. CT scan brain done for 5 patients revealed subdural haematoma in one. Cerebro spinal fluid (CSF) and EEG findings were noncontributory. All made good recovery with heavy doses of intravenous vitamin B complex, glucose and oral benzodiazepine. Short course of haloperidol was used in 2 patients. Two patients developed pancreatitis during follow up. All patients made complete recovery, and 8 patients have been followed for 8 to 12 months without relapse. The reason for hospitalisation in such cases is often unrelated to alcohol abuse; hence a detailed history of alcoholism is mandatory to identify those at risk as well as for prompt treatment and decreasing the mortality.Key Words: Alcohol withdrawal, Concomitant illnesses, Delirium, Precipitating events