Expression of scatter factor in human bladder carcinoma

BACKGROUND

Scatter factor (SF) is a protein secreted by stromal (supporting) cells that induces disruption of intercellular junctions and stimulates motility and invasiveness of carcinoma cells. SF is also a potent inducer of angiogenesis (new blood vessel formation), a process required for tumor growth and dissemination. Invasion and angiogenesis are characteristics of biologically aggressive tumors, suggesting that the accumulation of SF within tumors might promote progression to a more malignant phenotype.

PURPOSE

This study was designed to determine if SF is overexpressed in carcinoma of the bladder and to evaluate the potential mechanisms that might account for such overproduction.

METHODS

We measured the SF content in urine from 20 patients with carcinoma of the bladder and various control groups. We also measured expression of SF in bladder tumor extracts, histologic sections of tumors, and cell culture models, using a variety of techniques, including enzyme-linked immunosorbent assays, immunohistochemistry, and Western and Northern blot analyses. Statistical comparisons were performed using two-tailed t tests.

RESULTS

Urinary SF content was found to be significantly elevated in patients with bladder carcinoma as compared with normal control subjects (P < .001), patients with benign prostatic hypertrophy (P = .0055), and patients with prostate carcinoma, another genitourinary malignancy (P = .002). Extracts of bladder cancers, especially those from high-grade, invasive tumors, contained very high levels of SF. Both SF and its proto-oncogene (c-met)-encoded receptor were detected in bladder carcinoma tissue sections by immunostaining. Three different bladder carcinoma cell lines produced no detectable SF but produced very high titers of a high-molecular-weight (> 30 kd), heat-sensitive protein that stimulates SF production by stromal cell types. High titers of a similar SF-inducing activity were detected in vivo, in bladder carcinoma extracts, and in the urine of patients with bladder carcinoma.

CONCLUSIONS

Our results suggest that SF is overproduced in bladder carcinomas and accumulates within the tumor and in the urine. Overproduction of SF may result from an abnormal urothelial-stromal interaction in which dysplastic or carcinomatous urothelium secretes factors that stimulate SF expression by bladder wall stromal cells.

IMPLICATION

Quantitation of SF in the urine and tumor deserves further study as a possible marker of urothelial malignancy.

Preliminary structure determination of the capsular polysaccharide of Vibrio cholerae O139 Bengal Al1837

Vibrio cholerae O139 Bengal has recently been identified as a cause of epidemic cholera in Asia. In contrast to V. cholerae O1, V. cholerae O139 Bengal has a polysaccharide capsule. As determined by high-performance anion-exchange chromatography and 1H nuclear magnetic resonance analysis, the capsular polysaccharide of V. cholerae O139 Bengal strain Al1837 has six residues in the repeating subunit; this includes one residue each of N-acetylglucosamine, N-acetylquinovosamine (QuiNAc), galacturonic acid (GalA), and galactose and two residues of 3,6-dideoxyxylohexose (Xylhex). The proposed structure is [formula: see text]

Sphincterotomy: long-term complications and warning signs

Transurethral sphincterotomy is a commonly performed operation in spinal cord injury patients. Sixty-three patients who have had transurethral sphincterotomy were evaluated at our spinal cord injury unit for the risk and possible predictors of long-term outcome associated with this procedure. In addition to history and physical examination, all patients had urine culture, blood urea and creatinine, intravenous pyelogram and/or KUB with renal ultrasound, 4 channel videourodynamics, voiding cystourethrogram, and cystocopy when indicated. Their mean age was 53 years, and their level of injury was cervical 32, thoracic 25, and lumbar 6. The mean time since injury was 27 years (3-50), and the mean follow-up since their last sphincterotomy was 11 years (2-30). The mean number of sphincterotomies was 1.74 (1-4). Urine culture revealed bacteruria (asymptomatic) in 48 and sterile urine in 15 patients. Renal function was normal in 61 patients and abnormal in 2 patients. Videourodynamics revealed detrusor hyperreflexia in 60, detrusor areflexia in 3, abnormal detrusor compliance in 9, and detrusor sphincter dyssynergia in 34 patients. The mean Leak point pressure was 36.4 cm H2O (5-100), and the mean maximum detrusor pressure was 54.7 cm H2O (12-100). Nineteen (30%) patients had significant upper tract complications including; renal calculi, atrophic kidney, vesicoureteral reflux, and renal scarring with impaired renal function. Fifty percent of upper tract complications developed more than 2 years after sphincterotomy. Thirty patients had lower tract complications including; recurrent symptomatic urinary tract infection, bladder stones, urethral diverticulum, urethral stricture, bladder neck stenosis, and recurrent epididymitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Familial microcephaly with severe neurological deficits: a description of five affected siblings

Autosomal recessive microcephaly is usually characterized by normal developmental milestones and minor neurological deficits. In this report, we describe five siblings in one family with marked microcephaly, intractable seizures, quadriplegia and profound mental retardation. The recurrence risk of microcephaly when associated with devastating neurological deficits, as exemplified by this family, may be high and in such cases, the role of appropriate genetic counseling is of utmost importance.

Coagulation protein function. II. Influence of thiols upon acetaldehyde effects

It has been reported that prolonged prothrombin time may be a result of the interaction of acetaldehyde (AcH) with clotting proteins to form alkylated inactive products. The current investigation focuses on the influence of L-cysteine (CysH), DL-homocysteine (HC), D-penicillamine, N-acetyl-L-cysteine (NAC), L-serine and L-alanine at 0.01 M concentrations, lactalbumin hydrolysate (2 mg/ml), and 1.0 mM dithiothreitol (DTT) on clotting time as well as their interaction with AcH. The sulfhydryl amino acids, as well as DTT prolonged clotting upon preincubation with plasma. Cysteine and NAC, upon addition to plasma prior to the addition of AcH, exhibited a prolongation of clotting time compared to that of AcH alone. On sequential addition of serine, alanine, or lactalbumin hydrolysate to plasma followed by the addition of acetaldehyde, a prolongation of clotting time comparable to that of AcH alone was exhibited. When HC and penicillamine were added to plasma prior to the addition of AcH, a prolonged clotting time was observed, which was significantly less than that of AcH alone. Premixing of serine, alanine, and lactalbumin hydrolysate with AcH for 20 min prior to addition to the plasma reduced the effectiveness of AcH in prolonging clotting time as compared to successive additions of the amino acid and AcH. Since CysH and penicillamine have been reported to form cyclic adducts with AcH, it is suggested that a similar possibility exists for penicillamine and for HC. The reversible cyclic adduct formation reported for CysH may explain why cysteine did not lower the prolonged clotting time induced by AcH.(ABSTRACT TRUNCATED AT 250 WORDS)

The capsule and O antigen in Vibrio cholerae O139 Bengal are associated with a genetic region not present in Vibrio cholerae O1

Vibrio cholerae O139 Bengal, although closely related to V. cholerae O1 El Tor, produces a polysaccharide capsule and has a distinct O antigen. We have identified a chromosomal region of at least 11 kb, as defined by three TnphoA mutations, that is required for the expression of both polysaccharides. Electron microscopy and sodium dodecyl sulfate-polyacrylamide gel electrophoresis show that these TnphoA mutants have lost the abilities both to express capsule and to produce lipopolysaccharide beyond the core oligosaccharide. Reactivity with O139 typing serum and resistance to serum are also lost in the mutants. DNA probes for this region do not hybridize with O1 V. cholerae but do react with other vibrios, implying that the region was recently acquired.

Ten-year course of schizophrenia--the Madras longitudinal study

Ninety first-episode patients fulfilling ICD-9 criteria for schizophrenia were followed up prospectively for 10 years. Complete assessments were possible on 76. The pattern of illness was good in 67% of the cases, and the commonest patterns was one with recurrent episodes. Predictors of poor course and longer time spent in psychosis were identified. All positive and negative symptoms showed a steep decline at the end of 10 years. The results are discussed in the context of longitudinal research on the course of schizophrenia in developing countries.

Acetaldehyde alters coagulation protein function

Acetaldehyde is the first metabolite of ethanol and has the potential to react with proteins and alter their function. This study evaluated the function of clotting proteins that had been preincubated with acetaldehyde as compared to those incubated with buffer or ethanol as controls. Thrombin, fibrinogen, thromboplastin, or whole plasma were preincubated with 1.8-447 mM acetaldehyde, 1.7-429 mM ethanol, or buffer for varying time periods prior to use in a clotting assay. Clot formation was measured with an automatic fibrometer. Acetaldehyde prolonged the clotting time but ethanol did not. These experiments indicate that circulating acetaldehyde would have the potential to react with proteins of the clotting system and alter their function. Therefore, it is possible that not all of the abnormalities in coagulation in alcohol abusers result from inadequate hepatic synthesis. Perhaps some of the deranged coagulation may be the result of the interaction of acetaldehyde with coagulation proteins.

Regulation of scatter factor production via a soluble inducing factor

Scatter factor (SF) (also known as hepatocyte growth factor [HGF]) is a fibroblast-derived cytokine that stimulates motility, proliferation, and morphogenesis of epithelia. SF may play major roles in development, repair, and carcinogenesis. However, the physiologic signals that regulate its production are not well delineated. We found that various human tumor cell lines that do not produce SF secrete factors that stimulate SF production by fibroblasts, suggesting a paracrine mechanism for regulation of SF production. Conditioned medium from these cell lines contained two distinct scatter factor-inducing factor SF-IF activities: a high molecular weight (> 30 kD), heat sensitive activity and a low molecular weight (< 30 kD) heat stable activity. Further studies revealed that SF-producing fibroblasts also secrete factors that stimulate their own SF production. We characterized the < 30-kD SF-IF activity from ras-3T3 (clone D4), a mouse cell line that overproduces both SF and SF-IF. The < 30-kD filtrate from ras-3T3 conditioned medium induced four- to sixfold increases in expression of SF biologic activity, immunoreactive protein, and mRNA by multiple SF-producing fibroblast lines. Ras-3T3 SF-IF activity was stable to boiling, extremes of pH, and reductive alkylation, but was destroyed by proteases. We purified ras-3T3 SF-IF about 10,000-fold from serum-free conditioned medium by a combination of ultrafiltration, cation exchange chromatography, and reverse phase chromatography. The purified protein exhibited electrophoretic mobility of about 12 kD (reduced) and 14 kD (nonreduced) by SDS-PAGE. The identity of the protein was verified by elution of biologic activity from gel slices. Purified SF-IF stimulated SF production in a physiologic concentration range (about 20-400 pM). Its properties and activities were distinct from those of IL-1 and TNF, two known inducers of SF production. We suggest that SF-IF is a physiologic regulator of SF production.

Central opioid receptor subtype mediation of isoproterenol-induced drinking in rats

Opioid receptor subtype antagonists differentially alter different types of water intake such that mu2 receptors modulate deprivation-induced water intake, kappa receptors modulate hypertonic saline-induced water intake, and mu2, delta1 and kappa receptors modulate water intake following Angiotensin II (ANG II). Water intake stimulated by peripheral administration of the beta-adrenergic agonist, isoproterenol is attenuated by naloxone and is thought to be mediated by release of renin and production of ANG II. The present study examined whether systemic and i.c.v. administration of general opioid antagonists and central administration of specific opioid receptor subtype antagonists would selectively alter water intake following isoproterenol in rats. Both systemic (1 mg/kg s.c.) and central (1-20 micrograms) naltrexone reduced water intake induced by isoproterenol (25 micrograms/kg s.c.) over a 2-h period. The mu receptor antagonist, beta-funaltrexamine (B-FNA: 1-20 micrograms), but not the mu1 antagonist, naloxonazine (50 micrograms), dose-dependently reduced isoproterenol drinking. Both the kappa antagonist, nor-binaltorphamine (Nor-BNI, 5-20 micrograms) and the delta1 antagonist, [D-Ala2, Leu5, Cys6]-enkephalin (DALCE, 1-40 micrograms) also dose-dependently reduced isoproterenol drinking. These data implicate mu2, kappa and delta1 sites in the opioid modulation of isoproterenol drinking.

Clinical and angiographic variables affecting the progression of coronary artery disease as determined by quantitative angiography

To assess by serial quantitative angiography, the significance of clinical and angiographic variables that affect the progression of coronary artery disease (CAD). Progression of disease by sequential angiography is unpredictable and the role of clinical risk factors controversial. Various intervention trials have demonstrated less progression and even regression in hyperlipidemic patients. Correlates of progression have included a younger age, unstable angina, and greater involvement of the coronary arteries, with few studies looking at angiographic features of individual lesions. Serial angiograms on 74 patients were analyzed by computer assisted quantitative angiography using absolute measurements. A total of 99 diseased segments were analyzed for progression defined as an absolute reduction of 20% in luminal cross-sectional area. A preliminary correlation coefficient was calculated for each of the clinical and angiographic variables to detect any association with progression, and the odds ratio determined. The presence of any of the clinical risk factors-diabetes, hypertension, serum cholesterol, smoking, and a family history of coronary disease could not predict progression. The use of beta blockers was three times less likely to be associated with progression (odds ratio 0.33). While the presence of distal disease was associated with progression of a more proximal lesion (odds ratio 2.4), eccentricity, branch point location, lesion length, calcification, thrombus, or the presence of collaterals did not influence progression of disease in an individual segment. In conclusion, the presence of any of the clinical risk factors could not predict progression of disease in an individual coronary segment as determined by serial quantitative angiography, and the use of beta blockers and the absence of coexistent distal disease was associated with less progression of disease in an individual coronary segment. This may be related to changes in wall stress, reduced platelet interactions, and the integrity and permeability of the vascular endothelium to lipids.

Splenic reimplantation does not affect outcome in chronic canine model

The effects of septic insult were compared in a canine model of splenic reimplantation. Sequential changes in hematologic, hepatic, and immunologic function were monitored biweekly in 18 dogs during 10 months after splenectomy, splenectomy with reimplantation, or sham operation. There was no significant difference in these measures between the two groups. At the end of the 10-month period, spleen scans with technetium (99Tc) labeled, heat-damaged RBCs were obtained on the reimplanted dogs. 99Tc scanning revealed no active splenic implants at 10 months. All dogs were then infected with intravenous Type III pneumococcus for 9 consecutive days. There were no measurable hematologic, hepatic, or immunologic differences between groups before or after the septic insult. These animals were then sacrificed for histologic analysis of the splenic reimplants. Reimplant histology showed active germinal centers, but the surrounding pulp was fibrotic and lymphocyte-depleted. Splenic reimplantation in this canine model yields no apparent benefit.

Expression of scatter factor/hepatocyte growth factor is regionally correlated with the initiation of sperm motility in murine male genital tract: is scatter factor/hepatocyte growth factor involved in initiation of sperm motility?

Based upon findings that the scatter factor/hepatocyte growth factor (SF/HGF) has strong mitogenic and motogenic properties, and that the sperm cell acquires its fertilizing capacity and motility in the distal parts of mammalian epididymis, the present study was conducted to investigate the role of SF/HGF in initiation of sperm cell motility. This was investigated by determining the expression of SF/HGF in various regions of the murine male genital tract by scatter and cell tracking assays using MDCK epithelial cells, Western blot procedure, and the immunohistochemical procedure using paraffin sections of various regions of the male genital tract. The findings from all these assays indicate that SF/HGF is differentially expressed in various parts of the male genital tract with slight or no expression in the testes, caput epididymis, and vas deferens, and with the highest expression in cauda and corpus (distal) epididymis followed by expression in the corpus (proximal) epididymis. This region-specific SF/HGF expression pattern coincides with the pattern of acquiring the fertilizing capacity and motility by the sperm cell during its transit through the male genital tract. However, wherever SF/HGF was expressed in the male genital tract, its molecular weight was slightly higher (Mr, 82 kD), compared to the SF/HGF expressed in various other somatic tissues (Mr, 78 kD), indicating that the genital tract SF/HGF may be a different molecular species that shares some immunoreactive epitopes with the somatic cell SF/HGF. Incubation of immotile sperm from caput epididymis with the purified human placental SF/HGF of 78 kD initiated motility in 5-15% of sperm population. These results strongly suggest that the SF/HGF-like activity is expressed in the male genital tract in a region-specific manner, and this activity may have a role in initiation of sperm motility acquired during its transit through the epididymis in mammals.

Spontaneous improvement in a patient with the hepatopulmonary syndrome assessed by serial exercise tests

A 37 year old patient with chronic active hepatitis progressing to cirrhosis presented with increasing breathlessness and was found to be hypoxic with finger clubbing. A progressive exercise study with measurement of oxygen saturation (SaO2) showed abnormally high ventilation and desaturation to 81% at 100 W. Serial studies over nearly two years showed, first, deterioration, then improvement with lower ventilation and higher saturation levels at all work loads. This could not be correlated with any change in treatment with azathioprine, prednisolone, or propranolol.

Scatter factor modulates the metastatic phenotype of the EMT6 mouse mammary tumor

EMT6 is a transplantable mouse mammary tumor cell line that has been utilized widely as a model system to study the effects of various treatments on local tumor growth and pulmonary metastasis. In this study, we examined the cellular mechanisms by which scatter factor (SF), a fibroblast-derived cytokine that stimulates epithelial cell motility, may contribute to tumor-cell dissemination, using the EMT6 model system. In vitro, SF stimulated EMT6 cell motility, invasiveness and cell-surface expression of urokinase (an enzyme required for cell migration through tissue). SF differentially stimulated EMT6 cell adhesion to and migration onto surfaces coated with collagen I and laminin. EMT6 cells treated in vitro with SF and injected i.v. into isogeneic BALB/c-Rw mice showed a small but significant increase (1.7-fold) in lung colony formation as compared with control cells. For EMT6 cells in vitro, SF had no effect on DNA synthesis, cell proliferation, cell size distribution, or in vitro colony-forming ability. Thus, the increase in lung colonization may be due to enhanced ability of SF-treated cells to adhere to subendothelial basement membrane or to invade through tissue. Studies of the tissue distribution of SF in BALB/c-Rw mice demonstrated high levels of active factor in the lung. Thus, the presence of endogenous pulmonary SF may have reduced the degree to which SF treatment stimulated EMT6 lung colonization. Significant SF activity was also found in extracts of EMT6 tumors. Cultured EMT6 cells did not produce SF, but did produce high titers of a soluble low-molecular-weight protein activity that is capable of stimulating SF production in human fibroblasts 3- to 5-fold. EMT6 tumor extracts contained high titers of a similar SF-inducing activity. These observations suggest that SF may contribute to the invasive and metastatic phenotype of EMT6 cells via a paracrine mechanism in which tumor cells induce the production of SF in stromal fibroblasts.

Effect of hepatocyte growth factor/scatter factor and other growth factors on motility and morphology of non-tumorigenic and tumor cells

Using an automated cell analyzer system, the effect of hepatocyte growth factor/scatter factor (HGF/SF), epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), endothelial acidic fibroblast growth factor (a-FGF), platelet derived growth factor (PDGF), and recombinant human insulinlike growth factor (IGF) on the motility and morphology of Madin-Darby canine kidney (MDCK), rat hepatomas, C2, and H5-6 and murine mammary carcinoma (EMT-6) cells was investigated. Treatment of MDCK cells with HGF/SF, bFGF, EGF, and a-FGF resulted in an increase in average cell velocity and in the fraction of moving cells. Cells treated with the PDGF and IGF did not show significant alterations in velocity. MDCK cells treated with each growth factor were classified into groups of "fast" and "slow" moving cells based on their average velocities, and the average morphologic features of the two groups were quantitated. Fast-moving cells had larger average area, circularity, and flatness as compared to slow-moving cells. Factors that stimulated cell movement also induced alterations in cell morphologic parameters including spreading, flatness, area, and circularity. HGF/SF also scattered and stimulated motility of C2 and H5-6 hepatoma cells. In contrast to MDCK cells, there was no significant difference between the morphology of the fast moving and slow moving C2 and H5-6 cells. These studies suggest that growth factor cytokines have specific effects on motility of normal and tumor cells.

Delusions of pregnancy

We report five cases of delusions of pregnancy of whom three were women and four had chronic schizophrenia. We draw the attention of clinicians to this symptom which is not as rare as has previously been thought.

3-Methylglutaconic aciduria in the Iraqi-Jewish 'optic atrophy plus' (Costeff) syndrome

Eleven new patients of Iraqi-Jewish origin with bilateral optic atrophy, neurological abnormalities ('optic atrophy plus' syndrome) and 3-methylglutaconic aciduria (type III) are described. Clinical abnormalities in decreasing order of frequency were bilateral optic atrophy, extrapyramidal signs, spasticity, ataxia, dysarthria and cognitive deficit. An association with age was found only for spasticity. Spasticity, extrapyramidal signs and optic atrophy frequently led to major disability, in contrast to ataxia, dysarthria and cognitive deficit. The combined excretion of 3-methylglutaconic and 3-methylglutaric acid ranged between 9 and 187 mmol/mol creatinine. The primary enzymatic defect possibly may reside in the mitochondrial respiratory chain.

Cloning and characterization of the human t(3;6)(p14;p11) translocation breakpoint associated with hematologic malignancies

The t(3;6)(p14;p11) chromosome translocation was identified in a family in which three members developed hematologic malignancies. To help characterize the region on chromosome 3 surrounding this translocation breakpoint, two flanking lambda clones, MS156 and MJ1525, were linked by pulsed-field gel electrophoresis to the same 510-kb NotI fragment on chromosome 3. MS156 was localized to a region proximal to the breakpoint of a der(3) chromosome somatic cell hybrid (derived from the t(3;6) cell line), and MJ1525 localized distal to the breakpoint. MJ1525 was used to screen the CEPH yeast artificial chromosome (YAC) library, which revealed a YAC, 195F3, that spanned the breakpoint. Subcloning into Lambda DASH II and production of a contiguous array of overlapping lambda clones revealed a clone, L17, that spanned the breakpoint. A rare restriction endonuclease map for the YAC 195F3 was constructed, and multiple clusters of rare restriction sites within the YAC were identified, possibly indicating the disruption of a gene by the t(3;6) translocation breakpoint.

Rat placental hepatocyte growth factor/scatter factor: purification, characterization, and developmental regulation

In view of significant species-specific sequence differences between human and rat placental hepatocyte growth factor (HGF)/scatter factor (SF), the rat placental HGF/SF (rpSF) was purified, and its properties compared with human placental HGF/SF (hpSF). Like hpSF, rpSF scattered Madin-Darby canine kidney cells at 1-2 ng/ml and is composed of two subunits of 60 kDa and 30 kDa. Higher amounts (> 50%) of uncleaved 90-kDa form was present in the HGF/SF preparations from both human and rat placentas. Rat placental SF reacts with antibodies raised against hpSF in rabbits and chickens. The SF activity when expressed per gram rat placental tissue rises rapidly up to 9 days and then levels off. When expressed per milligram tissue protein it also increases rapidly up to 9 days and then declines. The expression of HGF/SF mRNA during development parallels that of HGF/SF activity. The specific activity of HGF/SF receptor (c-met) mRNA also appears to peak at 6 days. These findings suggest that (i) in spite of significant (> 10%) sequence differences between rpSF and hpSF, they exhibit similar structural, biologic, and immunologic characteristics and (ii) HGF/SF and its receptor are expressed in high amounts on Day 6 and then decline in developing placenta.

Manifestations of coronary atherosclerosis in young trauma victims--an autopsy study

OBJECTIVES

The aim of this study was to look at the prevalence of coronary atherosclerosis, its severity and site of involvement in patients < 35 years old who died from noncardiac trauma.

BACKGROUND

Autopsies performed on casualties of the Korean War revealed coronary artery involvement in 77.3% of the hearts studied, and data after the Vietnam War noted the presence of atherosclerosis in 45% of casualties with severe disease in 5%, suggesting a decline in the prevalence of coronary atherosclerosis in young men.

METHODS

One hundred eleven victims of noncardiac trauma (86.4% white with a mean age of 26 +/- 6 years) underwent pathologic examination of their coronary arteries to estimate the presence and severity of coronary atherosclerosis grossly, microscopically and through computerized planimetry. Identified segments of the coronary arteries were sectioned at 3-mm intervals, stained with special stains and after microscopic examination transferred to videotape and digitized to allow estimation of the percent compromise in the lumen area by atherosclerotic plaque.

RESULTS

Signs of coronary atherosclerosis were seen in 78.3% of the total study group, with > 50% narrowing in 20.7% and > 75% narrowing in 9%. No demographic or anatomic features separated the groups with less or more severe involvement of their coronary arteries. Proximal involvement was more common except in the right coronary artery, which was as frequently involved distally.

CONCLUSIONS

The overall prevalence of coronary atherosclerosis in a young, predominantly male study group was comparable with that noted after the Korean War. Left main or significant two- and three-vessel involvement was noted in 20% of the group studied and emphasizes the need for aggressive risk factor modification in this group.

Identification of a cDNA for a human high-molecular-weight B-cell growth factor

Proliferation is necessary for many of the phenotypic changes that occur during B-cell maturation. Further differentiation of mature B cells into plasma cells or memory B cells requires additional rounds of proliferation. In this manuscript, we describe a cDNA for a human B-cell growth factor we call high-molecular-weight B-cell growth factor (HMW-BCGF). Purified HMW-BCGF has been shown to induce B-cell proliferation, inhibit immunoglobulin secretion, and selectively expand certain B-cell subpopulations. Studies using antibodies to HMW-BCGF and its receptor have suggested that HMW-BCGF, while produced by T cells and some malignant B cells, acts predominantly on normal and malignant B cells. The HMW-BCGF cDNA was identified by expression cloning using a monoclonal antibody and polyclonal antisera to HMW-BCGF. Protein produced from the cDNA induced B-cell proliferation, inhibited immunoglobulin secretion, and was recognized in immunoblots by anti-HMW-BCGF antibodies. The amino acid sequence of HMW-BCGF deduced from the cDNA predicts a secreted protein of 53 kDa with three potential N-linked glycosylation sites. The identification of this cDNA will allow further studies examining physiologic roles of this cytokine. We propose to call it interleukin 14.

Recurrent metabolic decompensation in profound carnitine palmitoyltransferase II deficiency

A 3-year-old boy had recurrent episodes of lethargy, encephalopathy, and hepatomegaly accompanied by hypoglycemia, elevated liver aminotransferase and creatine kinase values, and nonketotic dicarboxylic aciduria; the serum carnitine level was moderately reduced. Carnitine palmitoyltransferase II activity was decreased in lymphocytes and fibroblasts. Therapy with L-carnitine and a diet low in long-chain triglycerides did not prevent recurrent episodes.