Expression of a gene encoding a specific human sperm protein in Chinese hamster ovarian cells

The cDNA (RSD-2) encoding a human sperm protein (YWK-II) was isolated from a rat testis lambda gt11 expression library. Its nucleotide sequence was determined. The deduced polypeptide showed high identity with the transmembrane-cytoplasmic domains of A4 amyloid precursor protein of Alzheimer's disease. The RSD-2 was inserted into the EcoRI site of the pSV2-EP vector to construct the pSVRS-2 vector. Chinese hamster ovarian (CHO-dhfr) cells were cotransformed with pSV2-neo and pSVRS-2. mRNA and chromosomal DNA prepared from the transformed cells interacted with [32P]RSD-2 as probe by dot hybridization. The production of the YWK-II protein was determined by staining with the YWK-II mAb by an indirect immunofluorescence technique. There was marked staining of the cytoplasm. The RSD-2 cDNA encoding the YWK-II sperm was expressed in the transformed CHO cells. The pSV2-EP vector and the CHO cell expression system can be utilized to produce sperm proteins for antifertility studies.

Gene expression of human sperm component related to A4 amyloid precursor protein

Monoclonal antibodies were raised against a specific human sperm protein and designated as the YWK-II mAb. The partial cDNA encoding the protein was isolated from a rat testis lambda gt11 expression library and the amino acid sequence of the protein was deduced. The cytoplasmic-transmembrane domains of the deduced protein had high homology with the A4 amyloid precursor protein of Alzheimer's disease. To evaluate the stage of spermatogenesis when the gene was expressed, single-stranded 35S-labeled RNA probes were prepared from the cDNA. By an in situ hybridization technique the mRNA for the antigen was detected in germ cells at all stages of spermatogenesis. The finding that the gene is expressed in spermatogonia suggests possible involvement in the initiation of germ cell differentiation or in the detachment of spermatogonia from the basement membrane.

[Clinicopathological study of osteosarcoma of the jaw]

Eighty-five cases of osteosarcoma of the jaw were analyzed for clinical and histologic characters. According to the predominant histologic differentiation of the tumor, it was divided into osteoblastic, chondroblastic and fibroblastic type. Chondroblastic osteosarcoma was associated with the worst survival rate. The histologic grade was closely related to the prognosis of tumor.

Expression of a gene encoding a rabbit sperm membrane protein in mammalian cells

A general mammalian expression vector designated pSV2-EP was reconstructed by inserting an oligonucleotide fragment into pSV2-dhfr. This vector allowed insertion of cDNAs with EcoRI cohesive ends. The pSV2-EP contains a simian virus 40 (SV40) early promoter, origin for DNA replication, SV40 poly-A site, splicing site, an initiator ATG downstream from the promoter and an EcoRI site for the insertion of cDNA fragment screened from lambda gt11 expression libraries. A recombinant plasmid (pS-VRS-1) was constructed by inserting RSD-1, a cDNA encoding a rabbit sperm tail protein, into the EcoRI site of the pSV2-EP vector. Chinese hamster ovarian (CHO) dhfr-negative cells were cotransformed with pSV2-dhfr and pSVRS-1 by the calcium phosphate method. In selective culture medium without thymidine and hypoxanthine, several cell lines were obtained containing mRNA and DNA that hybridized with RSD-1. One of these transformed cell lines stained intensely with anti-rSMP-B antibodies, demonstrating that the RSD-1 was expressed in the transformed CHO cells.

Expression of a full-length nonstructural protein NS1 of bluetongue virus serotype 17 in Escherichia coli

The relative abundance of the nonstructural protein NS1 in bluetongue virus (BTV)-infected cells, the existence of NS1 in the BTV particles and the highly conserved NS1 gene among BTV serotypes indicate the diagnostic potential of using NS1 in detecting BTV infections. In this study a NS1 gene was expressed with the T7 RNA polymerase expression system to produce a full-length NS1 protein. Sheep anti-NS1 antibodies were raised with the E. coli-produced NS1 and used to show that the NS1 proteins of the five BTV serotypes in the Unites States were immunologically indistinguishable.

Development of a novel Bacillus subtilis cloning system employing its neutral protease as screen marker

Part of the pUC19 polylinker sequence (33 bp) was inserted into the pro-peptide-coding region of the Bacillus subtilis neutral protease-encoding gene to replace a 93-bp FspI-HindIII fragment. This in-frame sequence replacement had little effect on the expression and secretion of the neutral protease. This plasmid can therefore be used as a cloning vector, and recombinant clones can be directly identified on skim milk indicator plates by the loss of a clear ring (or halo) around the colonies. This novel cloning system offers several advantages over existing B. subtilis cloning vectors: (i) convenient direct screening of recombinants; (ii) the use of inexpensive indicator; (iii) no restriction on the use of host strains; and (iv) the availability of seven frequently used unique cloning sites: BamHI, XbaI, SalI, PstI, SphI, HindIII, and EcoRI. This system also has the potential to be used as an expression/secretion vector.

[Study on T-lymphocyte culture and function of T-lymphocyte subsets in patients with aplastic anemia]

T-lymphocytes form the peripheral blood of 12 patients with aplastic anemia (AA) and 4 patients with aplastic anaemia-paroxysmal hemoglobinuria syndrome (AA-PNH) were cultivated and their subsets were measured by monoclonal antibodies CD4, CD8, CD25 with indirect immunofluorescence technique. Change of the proportion of T-lymphocyte subsets was observed in 5 patients with AA after the mononuclear cells were activated with phytohemagglutinin (PHA). Its was shown that the number of CFU-T of the patients with AA was apparently decreased in comparison with that of normal controls (P less than 0.05). Disorder of T-lymphocyte subsets took place in patients with AA. The percentages of CD8 and CD25 lymphocytes were increased. The helper: suppressor T-lymphocytes (CD4:CD8) ratio was significantly increased (P less than 0.01). In the cases of AA-PNH, the number of CFU-T was significantly increased (P less than 0.01) and that of T-lymphocyte subsets did not change. The ratio of CD4/CD8 in 5 patients with AA was further decreased after activating mononuclear cells with PHA. These results showed that the increase of T-lymphocytes in patients with AA may account for the low level of CFU-T; the high level of CFU-T in patients with AA-PNH may be related to the multiplication of bone marrow cells. However, there may be a potential disorder of immune system on patients with AA at the same time.

A seral epidemiological study of HIV transmitted through human seral gamma-globulin preparations

In order to study the potential risk of transferring HIV through human seral gamma-globulin preparations (immunoglobulin), indirect immunofluorescent antibody test (IFA) and Western Blot (WB) assay were applied to 343 random samples (sera) with previous injection of imported human seral gamma-globulins (Ig) positive for Human Immunodeficiency Virus (HIV) antibodies between 1981-1987 for the detection of HIV antibodies. All results were negative and tests on all 23 controls who had previously received Ig made in China also gave negative results. However all 12 batches of imported Ig collected from the above-mentioned users, were positive for HIV antibodies when tested by WB and IFA. This study shows that under normal conditions, human seral gamma-globulin does not transmit HIV.

Expression in Escherichia coli of the Bacillus subtilis neutral protease gene (NPRE) lacking its ribosome binding site

Bacillus subtilis neutral protease (NprE) is first produced as a precursor, pre-pro-NprE, which consists of a signal peptide or prepeptide for secretion (27 amino acid residues) and a pro-peptide (194 amino acid residues) between the signal peptide and the mature protease. While the wildtype nprE gene could not be maintained in Escherichia coli, we have been able to show that expression and secretion of the neutral protease can be achieved from the nprE gene when its ribosome binding site (RBS) is removed. The results suggest that the failure to observe expression of the wildtype nprE gene is due to the lytic effect of the nprE gene product on E. coli host cells and that translation initiation in E. coli can be achieved even in the absence of a classical ribosome binding site.

Inhibition of leukocyte chemotaxis by immunosuppressive agents. Specific inhibition of lymphocyte chemotaxis by cyclosporine

Since chemotaxis is an important mechanism by which leukocytes are recruited to allografts during rejection, the effect of immunosuppressant agents on in vitro chemotactic responses of neutrophils, monocytes, and lymphocytes was studied. Cyclosporine caused profound inhibition of lymphocyte chemotaxis to three different chemotactic factors at pharmacologic levels but had no effect on neutrophil or monocyte chemotaxis. Methylprednisolone and azathioprine both inhibited chemotactic responses of neutrophils and monocytes as well as lymphocytes. These data suggest that immunosuppressant agents are potent inhibitors of leukocyte chemotaxis and that drugs differ as to which leukocyte cell type they inhibit. The selective action of cyclosporine might explain why this drug is ineffective in reversing established rejection episodes in which monocytes and neutrophils are also involved. Inhibition of leukocyte chemotaxis may be an important mode of action of immunosuppressant drugs, and drug regimes might be adjusted to cause selective inhibition of particular cell types.

Site directed mutagenesis of subunit 8 of yeast mitochondrial ATP synthase. Functional and import properties of a series of C-terminally truncated forms

The function of the positively charged C-terminal region of mitochondrially encoded subunit 8 of yeast mitochondrial ATP synthase was investigated using derivatives truncated at each of the 3 positively charged residues (Arg37, Arg42 and Lys47). Each construct, allotopically expressed in the nucleus, was tested for its ability to import and assemble functionally into ATP synthase in yeast cells unable to synthesize mitochondrial subunit 8. The efficiency of import of each construct into isolated wild-type yeast mitochondria was also determined. One construct truncated at the penultimate residue of subunit 8 (Lys47) functions in vivo and shows efficient import in vitro. Thus subunit 8 can function with only two positively charged residues. The remainder of the subunit 8 variants failed to rescue in vivo. Since they all show greatly reduced or undetectable import in vitro, presumably because of the increased hydrophobic character of the subunit 8 moiety in the chimaeric precursors, the status of these variants as regards assembly and function is not clear.

[Effect of drug volume on spinal anesthesia with isobaric tetracaine]

The effects of drug volume on spinal anesthesia with 10 mg tetracaine in 1 ml or 2 ml isobaric solution were studied in 100 demographically compatible patients in a randomized double-blind manner. Identical technique was used for every patient in the study except for the volume of anesthetic solutions. Drugs were administered in a lateral decubitus position and patients remained horizontal during the study. Hoghest cephalad spread of analgesia varied from T12-T3, with a median sensory level of T7 in those who received 2 ml solutions, compared with T12-T5 and a median level of T10 in those who received 1 ml solutions. The time for maximum spread was longer in 2 ml--group (7.54 +/- 1.76 min vs 4.85 +/- 1.54 min). The 2-segment regression times were 180 +/- 53.44 min (mean) with a range of 75-270 min, and 219 +/- 34.11 min (mean) with a range of 150-300 min respectively for the 2 ml--group and the 1 ml--group. The differences were statistically significant. Complete motor blockade of the lower extremities as assessed by the modified Bromage scale was achieved in 35 out of 50 patients given 2 ml solutions, while all those who received 1 ml solutions achieved complete motor blockade. The onset times of maximum blockade were 5.42 +/- 1.59 min (mean) with a range of 2-10 min, and 5.98 +/- 1.79 min (mean) with a range of 2-12 min respectively. The difference between the degree of maximum motor blockade was also statistically significant but was insignificant regarding the time to maximum motor blockade.(ABSTRACT TRUNCATED AT 250 WORDS)

Neutrophil activation--an important cause of tissue damage during liver allograft rejection?

Although neutrophils have been implicated as mediators of tissue damage in a variety of conditions, their role in graft rejection has not previously been studied. Peripheral neutrophil activation was assessed sequentially in 16 patients following liver transplantation by measuring the ability of neutrophils to respond to the chemotactic peptide FMLP, to release superoxide radicals, and to cause extracellular proteolysis. All three functions increased 1-2 days before episodes of acute rejection and only returned to normal after treatment with high-dose corticosteroids. Three patients who did not develop rejection showed no increase in neutrophil function. Lymphocytes isolated from patients with acute rejection produced factors that were both chemotactic for and capable of activating normal neutrophils. This study shows that neutrophil activation occurs during acute liver allograft rejection, possibly in response to lymphokine secretion, and suggests an important, and hitherto unrecognized, mechanism of graft damage during rejection.

Expression of a sperm protein gene during spermatogenesis in mammalian testis: an in situ hybridization study

In previous work a specific membrane protein with an estimated Mr of 20.1 kDa was purified from rabbit sperm tails and designated as rSMP-B protein. Antibodies were raised against rSMP-B protein and used to isolate and identify the cDNA coding the rSMP-B protein from a rat testis lambda gt11 expression library. The nucleotide sequence of the cDNA was determined in a previous study. Single-stranded 35S-labeled RNA probes were prepared. With the techniques of in situ hybridization, rSMP-B mRNA was detected in spermatids of rat and rabbit testis. The present results support our previous observation that immunization of male rabbits with the rSMP-B protein results in the arrest of spermatogenesis at the spermatid stage. Overall, rSMP-B protein appears to be involved in spermiogenesis, and the synthesis of the mRNA encoding the protein occurs in germ cells during the postmeiotic haploid phase of spermatogenesis.

Characterization of cDNA encoding a human sperm membrane protein related to A4 amyloid protein

A rat testis lambda gt11 cDNA library was screened with a monoclonal antibody raised against a human sperm membrane protein designated YWK-II. A clone was found with a cDNA insert composed of 1837 base pairs that contained an open reading frame coding for 191 amino acid residues. The deduced polypeptide contained a segment with high homology to the transmembrane-cytoplasmic domains of the A4 amyloid protein found in brain plaques of Alzheimer disease patients. A sequence of basic amino acid residues, Arg-Lys-Arg, was found instead of Lys-Lys-Lys at the probable membrane-cytoplasmic junction that may be a unique property of sperm membrane proteins.

Complex character of senS, a novel gene regulating expression of extracellular-protein genes of Bacillus subtilis

The senS gene of Bacillus subtilis, which in high copy number stimulates the expression of several extracellular-protein genes, has been cloned, genetically mapped, and sequenced. The gene codes for a highly charged basic protein containing 65 amino acid residues. The gene is characterized by the presence of a transcription terminator (attenuator) located between the promoter and open reading frame, a strong ribosome-binding site, and a strong transcription terminator at the 3' end of this monocistronic gene. The amino acid sequence of SenS showed partial homology with the N-terminal core binding domain region of bacterial RNA polymerase sigma factors and a helix-turn-helix motif found in DNA-binding proteins. The gene can be deleted without any effect on growth or sporulation.

Synthesis and refolding of human tissue-type plasminogen activator in Bacillus subtilis

A 1.6 kb cDNA fragment encoding the mature part of the human tissue-type plasminogen activator (t-PA) was subcloned into a Bacillus subtilis dual plasmid expression system [Le Grice et al., Gene 55 (1987) 95-103]. Expression of the tPA gene in this vector was regulated by the inducible Escherichia coli lac elements, as well as a strong phage-T5-derived promoter and ribosome-binding site preceding the polylinker. The 5' end of the tPA gene corresponding to the N terminus of mature t-PA was fused in phase to the third codon present in the polylinker region of the expression vector, p602/22, to form p602-t-PA. B. subtilis containing p602-t-PA, when induced with isopropyl-beta-D-thiogalactopyranoside, produced large amounts of immunoreactive t-PA (approx. 20 micrograms/ml). As expected, t-PA was not secreted into the culture media, but was localized in intracellular inclusion bodies and was found to be enzymatically inactive. However, enzymatic activity could be regained following complete reduction followed by slow oxidation of the solubilized inclusion bodies. The recombinant t-PA (rt-PA) showed, after purification, a smaller molecular size than melanoma t-PA, probably due to lack of glycosylation in the Bacillus system. Like melanoma t-PA, rt-PA exhibited tremendous stimulation of plasminogen activation in the presence of fibrin. Our results illustrate that B. subtilis, when supplied with the proper transcriptional/translational regulatory elements, can be an effective system for expression of heterologous gene products.

Bluetongue virus-17 fusion protein ns1 expressed in Escherichia coli by pUC vectors

The cDNA coding for the major nonstructural protein, NS1, of bluetongue serotype 17 (BTV-17) was cloned previously. Using pUC plasmids, we have successfully expressed the NS1 protein in Escherichia coli as a LacZ-NS1 fusion protein. The recombinant NS1 protein reacted with rabbit anti-BTV-17 antiserum, and was thus immunologically indistinguishable from the native BTV-17 NS1 protein. This was the first bluetongue viral protein to be produced in a bacterial system.

[Mechanism of active oxygen in cytocidal activity of tetrabromofluorescein]

Photosensitization induced by tetrabromofluorescein (eosin, 3.8 mumol/L) in ascites hepatoma cells or in normal kidney cells of mice was found to be significant. The cytocidal activity increased in proportion to the concentration of fluorescein as well as with irradiation time. ESR signals were not detected using a trapping agent, 2,2,6,6-tetramethyltetrahydroxy-piperidine (TMHP) which functions as a singlet oxygen probe. No effect on photosensitization by superoxide dismutase (SOD), NaN3, histidine, mannitol or beta-carotene were observed. However, catalase did decrease photosensitization. These results indicate that cytocidal activity is not related to 1O2, O2-. or OH., but is related to H2O2. The cytocidal activity of tetrabromofluorescein in ascites hepatoma cells is stronger than that in normal kidney cells.

[Effects of the specific gravity on spinal anesthesia with 0.5% tetracaine]

In a double-blind study, 0.5% tetracaine 10 mg in hyperbaric or isobaric solution was administered intrathecally at random to 102 adult patients. Except the variable under study, identical technique was used for every patient enrolled. Other influential factors were also under careful control. The extent and pattern of anesthesia were compared. The time for maximal spread was short, the mean times was 7.74 min and 7.8 min for hyper-and isobaric groups respectively, there was no differences statistically. (P less than 0.05). The maximum cephalad spread was T5 (mean, range T12-T3) for the hyperbaric solution and T7 (mean, range T10-T3) for the isobaric solution. The difference was 2 dermatomes and was statistically significant (P less than 0.01). Forty three patients (86%) in the hyperbaric group and 16 patients (30%) in the isobaric group had a sensory blockade higher than T6 level. The hyperbaric group has a much higher percentage of high blockade. The isobaric group has a more predictory lower blockade, but occasionally blockade up to T3 did occur. The 2-segment regression times were also statistically significant. That of hyperbaric group was 88.9 min (mean, range 60-150 min) and 180.5 min (mean, 75-270 min) in isobaric group with a P value less than 0.01. Statistically significant differences in regard to maximum motor blockade and its onset times were found between the two groups. Maximum motor blockade assessed by modified Bromage scale was degree 2 (mean, range 1-3) for the hyperbaric group and degree 3 (mean, range 2-3) for the isobaric group.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacillus subtilis subtilisin gene (aprE) is expressed from a sigma A (sigma 43) promoter in vitro and in vivo

In vitro studies demonstrated that the Bacillus subtilis subtilisin gene (aprE) could be transcribed by RNA polymerase holoenzyme reconstituted from core and sigma A factor obtained from vegetative cells. Upstream deletions (from -45) reduced the amount of transcription from the promoter. A deletion downstream of the promoter that overlapped a putative downstream minor promoter did not affect transcription from the sigma A promoter, which indicated that the putative downstream promoter is not utilized in vivo. S1 nuclease mapping studies showed that there was a low level of transcription from the subtilisin promoter during the growth phase and that the site of transcription initiation was the same during log and stationary phases. We conclude from these findings that there is only one promoter for the subtilisin gene and that it can be transcribed by the sigma A form of RNA polymerase in vitro.