Epstein-Barr virus nuclear antigen 2 specifically induces expression of the B-cell activation antigen CD23

Epstein-Barr virus (EBV) infection of EBV-negative Burkitt lymphoma (BL) cells induces some changes similar to those seen in normal B lymphocytes that have been growth transformed by EBV. The role of individual EBV genes in this process was evaluated by introducing each of the viral genes that are normally expressed in EBV growth-transformed and latently infected lymphoblasts into an EBV-negative BL cell line, using recombinant retrovirus-mediated transfer. Clones of cells were derived that stably express the EBV nuclear antigen 1 (EBNA-1), EBNA-2, EBNA-3, EBNA-leader protein, or EBV latent membrane protein (LMP). These were compared with control clones infected with the retrovirus vector. All 10 clones converted to EBNA-2 expression differed from control clones or clones expressing other EBV proteins by growth in tight clumps and by markedly increased expression of one particular surface marker of B-cell activation, CD23. Other activation antigens were unaffected by EBNA-2 expression, as were markers already expressed on the parent BL cell line, including BL markers (cALLA and BLA), proliferation markers (transferrin receptor and BK19.9), and cell adhesion-related molecules (LFA-1 and LFA-3). Increased CD23 expression in cells expressing EBNA-2 was apparent from monoclonal anti-CD23 antibody binding to the cell surface, from immunoprecipitation of the 45-kDa and 90-kDa CD23 proteins with monoclonal antibody, and from RNA blots probed with labeled CD23 DNA. The results indicate that EBNA-2 is a specific direct or indirect trans-activator of CD23. This establishes a link between an EBV gene and cell gene expression. Since CD23 has been implicated in the transduction of B-cell growth signals, its specific induction by EBNA-2 could be important in EBV induction of B-lymphocyte transformation.

A bicistronic Epstein-Barr virus mRNA encodes two nuclear proteins in latently infected, growth-transformed lymphocytes

EBNA2 is a nuclear protein expressed in all cells latently infected with and growth transformed by Epstein-Barr virus (EBV) infection (K. Hennessy and E. Kieff, Science 227:1230-1240, 1985). The nucleotide sequence of the EBNA2 mRNA (J. Sample, M. Hummel, D. Braun, M. Birkenbach, and E. Kieff, Proc. Natl. Acad. Sci. USA 83:5096-5100, 1986) revealed that it begins with a 924-base open reading frame that has an unusual potential translational initiation site (CAAATGG). This open reading frame is followed by 138 nucleotides with only one highly unlikely translational initiation site (TACATGC), which would translate a pentapeptide before the next stop codon. The last part of the mRNA is the open reading frame which encodes EBNA2. In this paper, we demonstrate that the 924-base open reading frame translates a 40-kilodalton protein in vitro or in murine cells transfected with the EBNA2 cDNA under control of the murine leukemia virus long terminal repeat. A protein of identical size was detected in EBV-transformed, latently infected human lymphocyte nuclei by using antibody specific for the leader open reading frame expressed in bacteria. Therefore, this is a rare example of a mRNA which translates two proteins from nonoverlapping open reading frames. Since the protein encoded by the leader of the EBNA mRNA is expressed in all nuclei of a latently infected cell line, it was designated EBNA-LP. EBNA-LP localizes to small intranuclear particles and differs in this respect from EBNA1, EBNA2, or EBNA3. EBNA-LP is not expressed in an EBV-transformed marmoset lymphocyte cell (B95-8) or in one EBV-infected Burkitt tumor cell line (Raji) but is expressed in three other Burkitt tumor cell lines (Namalwa, P3HR-1, and Daudi).

Suppressor T cell clones from patients with acute Epstein-Barr virus-induced infectious mononucleosis

Suppression and/or cytotoxicity are believed to play an important role in the defense against Epstein-Barr virus (EBV) infection. To analyze the role of suppressor T cells in relation to EBV, we sought to clone and study these T cells. Analysis of 152 T cell clones derived from the peripheral blood of two patients with acute EBV-induced infectious mononucleosis (IM) yielded 11 highly suppressive clones that had no cytotoxic activity for the natural killer sensitive K562 cell line, an autologous EBV-infected cell line, or an allogeneic EBV-infected B cell line. Four of six suppressor T cell clones also profoundly inhibited EBV-induced immunoglobulin production, and five of five clones delayed the outgrowth of immortalized cells. These results indicate that during acute IM, suppressor T cells capable of inhibiting B cell activation in the absence of cytotoxicity can be identified, and may play a key role in the control of EBV infection.

Ocular complications in strabismus fixus convergens

Two cases of strabismus fixus are described. Histopathological examination of the eyeballs from both patients revealed the following complications of this rare disorder: ocular ischemia, atrophy of the optic nerve, and old central retinal artery occlusion. These complications are likely to be secondary to the mechanical stretching and torsion of the optic nerve with subsequent strangulation of its blood supply. Early surgical correction of strabismus fixus is recommended.

The acidosis of cholera. Contributions of hyperproteinemia, lactic acidemia, and hyperphosphatemia to an increased serum anion gap

To study the metabolic acidosis that occurs during the diarrhea of cholera, we examined the serum anion gap in 21 patients with hypovolemic shock due to Vibrio cholerae infection. Measurements of serum electrolytes, as well as divalent cations and the anionic contributions of serum proteins, lactate, phosphate, and serum creatinine, were made at the time of admission, after rehydration, and during convalescence. At the time of admission, the mean serum concentration of sodium was 134.8 mmol (meq) per liter, that of chloride was 103.2 mmol per liter, and that of bicarbonate was 11.4 mmol per liter; the mean anion gap was 20.2 mmol per liter. The mean serum creatinine concentration was 2.48 mg per deciliter. The low serum bicarbonate level and the high serum anion gap were corrected by rehydration. The increased serum anion gap was caused by hyperproteinemia, lactic acidemia, and hyperphosphatemia, with anionic contributions to the rise in anion gap estimated as protein, 5.5 meq per liter; lactate, 2.5 meq per liter; and phosphate, 2.5 meq per liter. The hyperproteinemia was attributed to dehydration, the lactic acidemia to shock, and the hyperphosphatemia to acidosis and transient renal failure. The mean concentrations of serum calcium and magnesium were slightly elevated but did not affect the increased anion gap. These results indicate that severe cholera causes acidosis with relatively little change in serum chloride but an increased serum anion gap. The acidosis is more profound than would be expected on the basis of stool losses of bicarbonate, because of superimposed lactic acidemia and renal failure.

Epstein-Barr virus immortalization of normal cells of B cell lineage with nonproductive, rearranged immunoglobulin genes

Most continuous cell lines derived by EBV immortalization of peripheral blood cells are composed of phenotypically mature B lymphocytes, and secrete Ig. Occasionally, EBV-immortalized cell lines have failed to secrete Ig. Expansion and characterization of one of these EBV-induced cell lines, VDS-O, showed that in addition to a lack of Ig secretion, surface and intracytoplasmic Ig were absent. Cell surface phenotyping revealed that VDS-O belongs to the B cell lineage, because it expresses the B cell restricted antigens B1 and B4, while it lacks T cell and monocyte-associated determinants. Analysis of the Ig gene organization in VDS-O revealed that the Ig genes are rearranged for both heavy (gamma) and light (kappa) chains. However, the expected gamma-heavy chain and/or kappa-light chain RNA species were not detected. These findings demonstrate the existence in normal peripheral blood of cells of B cell lineage susceptible to EBV immortalization that have Ig genes that are rearranged but are nonproductive.

Epstein-Barr virus immortalization of normal cells of B cell lineage with nonproductive, rearranged immunoglobulin genes

Most continuous cell lines derived by EBV immortalization of peripheral blood cells are composed of phenotypically mature B lymphocytes, and secrete Ig. Occasionally, EBV-immortalized cell lines have failed to secrete Ig. Expansion and characterization of one of these EBV-induced cell lines, VDS-O, showed that in addition to a lack of Ig secretion, surface and intracytoplasmic Ig were absent. Cell surface phenotyping revealed that VDS-O belongs to the B cell lineage, because it expresses the B cell restricted antigens B1 and B4, while it lacks T cell and monocyte-associated determinants. Analysis of the Ig gene organization in VDS-O revealed that the Ig genes are rearranged for both heavy (gamma) and light (kappa) chains. However, the expected gamma-heavy chain and/or kappa-light chain RNA species were not detected. These findings demonstrate the existence in normal peripheral blood of cells of B cell lineage susceptible to EBV immortalization that have Ig genes that are rearranged but are nonproductive.

Expression of the Epstein-Barr virus nuclear protein 2 in rodent cells

A 3.0-kilobase-pair Epstein-Barr virus (EBV) DNA segment necessary for lymphocyte immortalization encodes at least part of a nuclear protein (EBNA2) which is characteristically expressed in latently infected, immortalized cells. A 1.5-kilobase open reading frame within this DNA segment has now been inserted into a murine leukemia virus (MuLV)-derived expression vector (pZIP-NEO-SV(X)1) which provides for transcription of heterologous DNA but not for translational start. Transfection of the recombinant DNA into NIH 3T3 cells resulted in expression of a full-sized EBNA2 which localized to the cell nucleus. Significant new evidence is thereby provided that this 1.5 kilobase open reading frame includes a translational start site and encodes the entire EBNA2 protein. Transfection of the recombinant DNA into a helper cell line (psi am22b) providing amphotropic MuLV-packaging functions resulted in the release of a recombinant MuLV carrying the EBNA2 gene. This recombinant virus can infect rodent cells and convert them to stable EBNA2 expression. Rat-1 cells infected with the MuLV EBNA2 recombinant expressed EBNA2 and grew more rapidly in medium supplemented with 1 or 0.5% fetal calf serum than did Rat-1 cells infected with MuLV vector lacking EBNA2. The Rat-1 cells expressing EBNA2 remained contact inhibited, anchorage dependent, and nontumorigenic in nude mice. Different EBV isolates have one of at least two EBNA2 alleles. Despite divergence between the two alleles, a human serum recognized the prototype EBNA2 allele (EBNA2A) as well as the variant EBNA2B allele characteristic of some Burkitt tumor EBV isolates. The EBNA2B allele was also expressed from the MuLV-derived vector. The reproducible expression of EBNA2A or EBNA2B from these recombinant vectors will facilitate analysis of the EBNA2A and EBNA2B phenotypes.

Definitive identification of a member of the Epstein-Barr virus nuclear protein 3 family

Some Epstein-Barr virus (EBV) immune human antisera are known to react with a 142-kDa protein, EBV-encoded nuclear antigen 3 (EBNA3), which, like EBNA1 and EBNA2, is likely to be involved in the establishment of latent infection or growth transformation. We have now constructed gene fusions between Escherichia coli lacZ and an EBV DNA open reading frame (BERF1; BamHI E fragment rightward open reading frame 1), which is transcribed into an mRNA in latently infected cells. Purified hybrid protein from one of these constructs, chosen because of its reactivity with EBNA3-positive human antisera, was used to affinity purify the specific antibody from human antiserum. This specific antibody was used to prove that EBNA3 is encoded, at least in part, by BERF1, and that EBNA3 is in the nucleus of each latently infected cell. In rodent cells, BERF1 encodes a 120- to 130-kDa protein, which translocates to the nucleus and is recognized by EBNA3-positive human antisera. Two other proteins similar in size to EBNA3 are detected in latently infected cells by EBV immune human antisera. Two EBV open reading frames related to BERF1 may encode these proteins.

Thyroid disorders in systemic lupus erythematosus

Of 319 patients with systemic lupus erythematosus (SLE), nine had thyrotoxicosis, three had hypothyroidism, and two had thyroiditis. This prevalence seems greater than that of similar thyroid disorders seen in the general population. It is suggested that patients with autoimmune thyroid disorders may develop SLE or vice versa. This association requires confirmation by prospective study.

Surgical repair of visceral artery occlusions in Takayasu's disease

We describe the surgical management of six patients with occlusive disease of the visceral arteries caused by Takayasu's arteritis. All patients suffered from renovascular hypertension and, in addition, three of the patients also had symptoms of mesenteric angina. Surgical repair is recommended in the "burn-out" phase of the disease when further progression of the disease is unlikely. Revascularization of the kidneys was by autotransplantation to the iliac vessels. Mesenteric or celiac artery inflow was provided by an extra-anatomic vein bypass graft from the iliac artery. In all cases distal disease-free vessels were available for reconstructive surgery.

Candida retinitis in bare lymphocyte syndrome

Bare lymphocyte syndrome (BLS) is a rare, severe combined immunodeficiency characterized by lack of expression of HLA A, B and C antigens and the absence of B2 microglobulins. Patients with BLS exhibit functional deficiency of both T and B cells resulting in bacterial as well as viral and fungal infection. Ophthalmic findings in this group of disorders have not been reported. We present a case of candida retinitis in a terminally ill 5-year-old girl with BLS.

Functional constituents of the active site of human neutrophil collagenase

A series of chemical modification reactions has been carried out to identify functional constituents of the active site of human neutrophil collagenase. The enzyme is reversibly inhibited by the transition metal chelating agent 1,10-phenanthroline, and inhibition is fully reversed by zinc. Removal of weakly bound metal ions by gel filtration inactivates collagenase, and activity is fully restored on immediate readdition of calcium. The enzyme is unaffected by reagents that modify serine, cysteine, and arginine residues. However, reaction with the carboxyl reagents cyclohexylmorpholinocarbodiimide and Woodward's Reagent K lowers the activity of the enzyme substantially. Acetylimidazole inactivates the enzyme, but activity is completely restored on addition of hydroxylamine. The enzyme is also inactivated by tetranitromethane, indicating that it contains an essential tyrosine residue. Acylation of collagenase with diethyl pyrocarbonate, diketene, acetic anhydride, or trinitrobenzenesulfonate inactivates the enzyme, and activity is not restored on addition of hydroxylamine, indicating the presence of an essential lysine residue.

Ocular findings in the facioauriculovertebral sequence (Goldenhar-Gorlin syndrome)

We reviewed the ocular findings in 57 consecutive patients with the facioauriculovertebral sequence (Goldenhar-Gorlin syndrome). Epibulbar choristomas were detected in 18 cases (32%), a much lower occurrence than reported previously. Various motility disorders (11 cases, 19%), blepharoptosis or narrow palpebral fissures (seven cases, 12%), eyelid colobomas (six cases, 11%), and lacrimal drainage system anomalies (six cases, 11%) were more frequent than previously noted. These ocular findings were more common in the patients with epibulbar choristomas. Of the various features of the Goldenhar-Gorlin syndrome (skin tags, microtia, hemifacial microsomia, and vertebral anomalies), only skin tags correlated positively with the laterality of epibulbar choristomas. Preauricular and facial tags represent choristomas, explaining their association with epibulbar choristomas and the laterality they share.

Keshan disease: an endemic cardiomyopathy in China

Keshan disease is an endemic cardiomyopathy in China. Morphologically, the condition is characterized by multifocal necrosis and replacement fibrosis of the myocardium, resulting in acute or chronic heart failure. Some patients with Keshan disease show the clinical features of congestive (dilated) cardiomyopathy, but the pathologic features of the two conditions are different. The etiology of Keshan disease remains unknown. It is likely that numerous agents work synergistically to cause the disease.

Mesangial IGM in minimal change glomerular disease: a clinicopathological study in a Malaysian population

During a 6 yr period, 105 (69%) of 153 patients in whom a histological diagnosis of minimal change glomerular disease was made had renal biopsy tissue suitable for immunofluorescence examination. Thirty seven (35%) patients showed glomerular mesangial deposits of IgM. All the patients presented with the nephrotic syndrome. We found no significant difference in age and sex prevalence, presentation, response to therapy and glomerular morphology between IgM positive and IgM negative groups. This study suggests that there is no necessity to categorize IgM positive minimal change glomerular disease as a separate entity.

Mechanism of NaCl secretion in rectal gland tubules of spiny dogfish (Squalus acanthias). III. Effects of stimulation of secretion by cyclic AMP

Segments of rectal gland tubules (RGT) the spiny dogfish (Squalus acanthias) were perfused in vitro to study the cellular mechanism by which NaCl secretion is stimulated. Transepithelial PD (PDte), transepithelial resistance (Rte), the PD across the basolateral membrane (PDbl), the fractional resistance of the lumen membrane (FR1), and the cellular activities for Cl-, Na+, and K+ (alpha cell x) were measured. In series 1 the effects of stimulation (S) (dbcAMP 10(-4, adenosine 10(-4), and forskolin 10(-6) mol x 1(-1) on these parameters were recorded and compared to nonstimulated state (NS). PDte increased from -1.9 +/- 0.2 mV to -11.0 +/- 0.9 mV (n = 51). PDbl depolarized from -86 +/- 1 to -74 +/- 1.4 mV (n =52), Rte fell from 29 +/- 2.8 to 21 +/- 2 omega cm2 (n = 23), and FR1 fell from 0.96 +/- 0.005 to 0.79 +/- 0.04 (n = 9). alpha cell K+ was constant (123 +/- 13 versus 128 +/- 17 mmol x 1(-1) (n = 6), but alpha cell cl- fell significantly from 48 +/- 4 to 41 +/- 3 mmol x 1(-1) (n = 7). alpha cell Na+ increased from 11 +/- 2.1 to 29.5 +/- 6.6 mmol x 1(-1) (n = 4). In series 2 the conductivity properties were examined by rapid K+, and Cl- concentration steps on the basolateral and luminal cell side respectively in NS and S states. In NS-segments reduction of bath K+ led to a hyperpolarization of PDbl with a mean slope of 28 +/- 1.3 mV/decade (n = 9) (as compared to 19 mV/decade for S-state).(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired cutis laxa and multiple myeloma

We report a patient with acquired cutis laxa and multiple myeloma, and the possible association between the two conditions is discussed.