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S Isojima

Publications and source records attributed to S Isojima.

At least 55 records · Page 3Linked to original sources
PubMed1988

Analyses of epididymal sperm surface antigens by monoclonal antibodies against hamster spermatozoa.

BALB/c mice were immunized with spermatozoa from cauda epididymides of hamsters and the immune spleen cells were fused with mouse myeloma cells (P3U1). Seven hybridomas (GHS-1,-2,-3,-4,-5,-6, and -7) that produced monoclonal antibodies (Mabs) binding to the epididymal spermatozoa were established. Three Mabs (GHS-3,-4, and -6) were IgM and the other four were IgG1. All Mabs reacted to hamster spermatozoa from cauda epididymides but none of the Mabs except GHS-5 and -7 reacted to spermatozoa in testis. GHS-5 and -7 Mabs bound to the acrosome region of spermatozoa in both testis and epididymis. The antigens corresponding to GHS-2, -4, and -6 Mabs appeared to be excreted from epithelial cells of caput epididymis, while those to GHS-1 and -3 Mabs seemed to be produced in cauda epididymis. Both groups of the antigens bound to the surface of spermatozoa during their epididymal transit. Immunoblotting analyses of epididymal fluid showed that the antigen epitopes corresponding to GHS-1,-2,-3,-4, and -6 Mabs were distributed to multiple components with different molecular weights ranging from over 100 to 25 kd. The distribution patterns of the epitopes corresponding to GHS-1 and -3 Mabs and GHS-2,-4, and -6 Mabs were very similar, respectively, but each group pattern was quite different from each other. GHS-5 Mab reacted to a component of sperm extract with a molecular weight of around 94 kd, while GHS-7 Mab failed to recognize any components transblotted.

Acrosome↗
PubMed1988

Immunogenicity of a 92kDa component of porcine zona pellucida isolated using a monoclonal antibody (3A4-2G1) exclusively cross-reactive with porcine and human zonae pellucidae.

Three monoclonal antibodies (Mabs) to solubilized porcine zona pellucida (s-PZP) were produced. They reacted exclusively to porcine and human zonae pellucidae (ZPe) and two of them blocked sperm penetration of ZP in humans by collaborating with goat anti-mouse gamma-globulin serum as a second antibody. The antigen corresponding to one of these Mabs (Mab 3A4-2G1) was fractionated from s-PZP by immunoaffinity chromatography bound Mab 3A4-2G1. The antigen corresponding to Mab 3A4-2G1 was further fractionated by SDS-PAGE and the protein band corresponding to 92kDa was found to react to Mab 3A4-2G1, as demonstrated by Western blotting. The 92kDa fraction of s-PZP was isolated and injected into mice with complete and incomplete Freund's adjuvants to obtain an antiserum. It was shown that the antiserum to the 92kDa molecule reacted in a tissue-specific manner to human ZP and exhibited a strong inhibitory effect on sperm penetration of ZP of human oocytes.

Animals↗
PubMed1988

Characterization of a small immunoreactive HCG-like component isolated from urine of a patient with choriocarcinoma.

An immunoreactive hCG-like substance with low molecular weight was isolated from the urine of a patient with choriocarcinoma and its characteristic properties were studied. The urinary hCG preparation was fractionated by gel filtration on a Sephadex G75 column and each fraction was assayed for hCG activities by an enzyme linked immunosorbent assay using a monoclonal antibody to hCG (Mab-5D4). Two immunoreactive hCG peaks were obtained. One was coeluted with ordinary hCG and the other was eluted after hCG-alpha. After refractionation on the same column, the hCG peak (Ag-2) with low molecular weight was radioiodinated with 125INA and applied to an immunoaffinity column bound Mab-5D4 for further purification. The purified 125I-labelled Ag-2 showed a high binding activity to a conventional rabbit anti-hCG serum and Mab-5D4. This Mab had binding specificity to hCG, hCG-beta and LH but not to hCG-alpha. However, this fraction did not bind to Mab-6E4 which possessed binding activities only to hCG, hCG-alpha and LH, nor to Mab-2F8 which was specific only to hCG. Autoradiography after SDS-Page of the immune precipitate which was made by 125I-labelled Ag-2 and Mab-5D4, revealed that the Ag-2 had a molecular weight of approximately 14,000 daltons. Lectin (LeH) affinity chromatography of the urinary hCG specimen from the same patient revealed that it contained two kinds of immunoreactive hCG. One did not bind to LeH column but the other did. A small immunoreactive molecule (Ag-2) was detected in the LeH-unbound fraction but not in the LeH-bound fraction. These results suggest that choriocarcinoma patients excrete in the urine a small LeH-unbound immunoreactive component which contains an antigen epitope common to hCG, hCG-beta and LH.

Antibodies, Monoclonal↗
PubMed1988

Production of heavy-chain class-switch variants of human monoclonal antibody by recombinant DNA technology.

We have previously established a human-mouse heterohybridoma (H6-3C4), which produced a human sperm-immobilizing antibody (mu, lambda of human type). The human rearranged immunoglobulin mu-chain and lambda-chain genes were cloned from the hybridoma H6-3C4. The cloned V region of the heavy chain (VH) gene was ligated to human immunoglobulin gamma 1-heavy chain constant region (C gamma 1) genes. This resulted in the heavy-chain class-switch from mu-chain to gamma 1-chain of H6-3C4 antibody. The class-switched heavy-chain gene as well as the cloned lambda-chain gene were introduced into mouse myeloma cell line X63Ag8.653 by protoplast fusion and electroporation. The stable transformants produced the human IgG monoclonal antibody, which fully retained specificity to human sperm cells and sperm-immobilizing activity.

Animals↗
PubMed1988

[Bovine cervical mucus as a substitute of human cervical mucus].

The sperm penetration test (SPT) in cervical mucus (CM) is an important test in screening for sperm-CM incompatibility. For a routine SPT, a sufficient amount of preovulatory CM is necessary, but the amount of human CM is often inadequate. We examined estrous bovine CM as a substitute for human CM in the SPT. Preovulatory human CM and estrous bovine CM were collected and stored frozen at -20 degrees C until use. After being thawed at room temperature, the two CM samples were compared as to their pH, spinnbarkeit and ferning patterns, and it was found that they are quite similar. In Kremer's method of SPT, sperm penetration distance, density and motility were similar in human and bovine CM for 12 hours, but thereafter sperm motility became much lower in bovine CM than in human CM. The results of SPT with spermatozoa from patients with oligozoospermia were quite similar in both CMs. When spermatozoa pretreated with antisperm antibody were used for SPT, sperm penetration was completely blocked in human CM, but no inhibition was seen in bovine CM. From these results, we conclude that bovine CM can be substituted for human CM for some, but not all, purposes.

Animals↗
PubMed1987

Identification of an H antigen-like blood group antigen in sera of cancer patients using a novel monoclonal antibody raised against endometrial carcinoma.

An IgM class monoclonal antibody (MAb) was derived by immunizing BALB/c mice with a human endometrial carcinoma cell line. This MAb, termed C12, exhibited strong reactivity against endometrial carcinoma, but lesser reactivity against normal endometria. The antigen recognized by MAb C12 (C12 antigen) was detected by radiometric assay in sera from patients with various carcinomas, but not in sera from patients without carcinomas or in sera from normal individuals. MAb C12 was found to agglutinate blood type O erythrocytes, but not A, B, or AB erythrocytes. To clarify the specificity of MAb C12, tissue staining experiments were performed in parallel using MAb C12, Ulex europaeus lectin I (anti-H), and a monoclonal anti-H antibody. In endometrial carcinoma tissues, both H and C12 antigens increased, but the C12 antigen showed a prominent increase, in contrast to the H antigen. Further, the C12 antigen was not found in endothelial cells of blood type O patients. In sera, the level of the H antigen varied according to the host's blood type. The sera from blood type O individuals possessed higher levels of the H antigen than those with blood type A or B. Thus, the H antigen showed no value as a tumor-associated serum marker. In contrast, the presence of the C12 antigen in sera was not determined by ABO blood group status. Thus, MAb C12 was demonstrated to be a unique MAb that reacts with an H-like antigen occurring in the sera of patients with carcinomas irrespective of ABO blood group status. MAb C12 may prove to be a useful marker for cancer patient serum.

ABO Blood-Group System↗
PubMed1987

Establishment of a murine monoclonal antibody against human clear cell carcinoma and analysis of the corresponding antigen.

A murine monoclonal antibody (Mab) 4B6, immunoglobulin M (IgM), lambda chain, against human clear cell carcinoma of the ovary was established. Mab 4B6 reacted specifically to clear cell carcinomas, but failed to react to other types of ovarian carcinomas, such as mucinous, serous carcinoma, and also failed to react to human normal organ tissues. Mab 4B6 recognized antigenic determinants located on the membranes of carcinoma cells. Antigenic substances corresponding to Mab 4B6 were detected in sera of patients with ovarian clear cell carcinoma by using Sandwich radiometric assays performed with Mab 4B6-coated microplates and 125I-Mab 4B6. Gel filtration on Sephacryl S-300 revealed that the antigen corresponding to Mab 4B6 possessed a molecular weight of 50 to 60 kDa. Furthermore, after periodic acid and enzyme treatments, it was suggested that the antigen epitope corresponding to Mab 4B6 contains a carbohydrate moiety.

Adenocarcinoma↗
PubMed1987

Establishment and characterization of a human hybridoma secreting monoclonal antibody with high titers of sperm immobilizing and agglutinating activities against human seminal plasma.

Peripheral blood lymphocytes isolated from an infertile woman possessing strong sperm immobilizing and agglutinating antibodies were stimulated by culturing with poke-weed mitogen (PWM) and spermatozoa from a healthy donor for 5 days. The stimulated lymphocytes were fused with mouse myeloma NS-1 by PEG-1000. Fused growing hybrid cells were observed in 58 of 96 wells, and 22 of these showed the production of human immunoglobulin. Among the 22, one hybridoma clone (H6-3C4) was found to produce human IgM (lambda) with strong sperm immobilizing and agglutinating activities. The supernatant from the culture medium contained approximately 1.5 microgram IgM/ml and the antibody titers were 5000 SI50 units on sperm immobilization and 1:1600 dilutions on sperm agglutination. The hybridoma H6-3C4 has continuously produced high titers of antibody exhibiting sperm immobilizing and agglutinating activities over 8 months and contains chromosomes of acrocentric type from mouse and metacentric type from human. The monoclonal antibody (Mab) H6-3C4 reacted specifically to human seminal plasma, ejaculated spermatozoa and male accessory gland but not to testis, any other somatic tissues, or secreted fluids tested. Immunofluorescence staining indicated that the antigen corresponding to Mab H6-3C4 was present over the surface of ejaculated spermatozoa. The binding of Mab H6-3C4 to human spermatozoa was blocked by the serum of the patient from whom the lymphocytes were obtained for cell fusion.

Adult↗
PubMed1987

Successful delivery in a female with thrombotic thrombocytopenic purpura.

A 28-year-old female, who suffered from thrombotic thrombocytopenic purpura (TTP) in the 14th week of her first pregnancy, recovered after a plasma exchange followed by an induced abortion. From six months after the abortion, she no longer required plasma infusions every 3-4 weeks to prevent a relapse of TTP manifested as thrombocytopenia, and complete remission continued until her next pregnancy. In her second pregnancy, she had an immediate relapse of TTP and responded to plasma infusion until the 24th week. However, the TTP gradually became resistant to plasma infusion, and developed into toxemia with edema, hypertension and proteinuria in the 27th week. Although the TTP was alleviated by the infusion of large amounts of plasma, the placenta failed as the result of numerous white infarcts. She delivered a 948 g live baby by cesarean section in the 33rd week. The baby had transient thrombocytopenia but did not suffer from TTP. The mother required plasma infusions every 3-4 weeks for about five months, and she has continued in remission.

Adult↗
PubMed1987

[Successful application of in vitro fertilization and embryo replacement in the treatment of infertile women with sperm immobilizing antibody].

Thirteen infertile patients (18 cycles) with sperm immobilizing antibodies were subjected to in vitro fertilization and embryo replacement (IVF-ER) therapy during 12 months from January to December 1985. Four patients became pregnant, two of them delivered healthy babies at term and 2 had abortions at 5 weeks and 12 weeks of gestation, respectively. In the same duration, 24 patients (28 cycles) with tubal factor and 4 patients (5 cycles) with male factor for infertility were subjected to IVF-ER, and two patients with tubal factor became pregnant and delivered healthy babies at term. In the patients with immunological factor, fertilization and cleavage rates per mature oocyte were 85.9% (55 fertilized/64 oocytes) and 81.3% (52 cleaved/64 oocytes) respectively, while the fertilization rates in patients with tubal factor and male factor were 70.5% (62 fertilized/88 oocytes) and 50.0% (6 fertilized/12 oocytes) respectively and all fertilized eggs in these patients developed to the cleavage stage. Thus fertilization and cleavage rates for mature oocytes from the patients with the immunological factor were slightly better than those with the tubal factor and much better than those with the male factor. The antisperm antibody titers (SI50) in sera determined by the quantitative sperm immobilization test ranged from 20 to 243 units while those in follicular fluids ranged from 21 to 160 units in the patients with the immunological factor. The follicular sperm immobilizing antibodies could be detected in any patient who had the antibodies in the serum. Immunoglobulin (IgG, IgA, IgM) concentrations in follicular fluids were not significantly different from each other in the patients with immunological, tubal and male factor for infertility.

Adult↗
PubMed1986

Microimmunofluorescence using Terasaki plates and direct plate freezing method--rapid and reliable screening system of hybridomas.

Microimmunofluorescence using Terasaki plates and a direct plate freezing method were combined for effective screening of hybridoma supernatants. The microplates, in which the fused cells (myeloma and spleen cells) were cultured and hybridoma colonies were growing, were frozen after harvest of supernatants and saved at -80 C for several weeks without affecting antibody production ability of hybridomas. Microimmunofluorescence was performed in Terasaki plates on which target cells were attached by poly-L-lysine and glutaraldehyde or by short time culture of the cells in Terasaki plates. The direct plate freezing method prevented initial hybridoma cells from changes or disappearance of antibody productions during screening of hybridoma supernatants; the microimmunofluorescence staining method permits fast and detailed estimation of specificity of antibodies of hybridomas by saving time and minimal consumption of supernatant for checking. The combination of these two methods is a powerful tool for obtaining desired monoclonal antibodies.

Animals↗
PubMed1986

Affinity to lectin, biological and immunological characteristics of human chorionic gonadotropins from pregnant women and trophoblastic tumour patients.

To compare the affinity to lectin of human chorionic gonadotropins (hCG) from pregnant women and trophoblastic tumour patients, a small amount of urine was fractionated by a lentil lectin (LcH) affinity chromatography. The LcH-bound fractions were eluted with 2% mannoside solution, and each fraction was assayed for hCG activities by radioimmunoassay. In pregnant women, more than 90% of hCG immunoactivity in urine was bound to the LcH column and eluted from it, whereas 8 to 26% and 37 to 51% of the activity were not adsorbed to the affinity column and were recovered in the LcH-unbound fraction in the patients with hydatidiform mole and choriocarcinoma, respectively. These results suggest that LcH affinity chromatography of urinary hCG contributes to differential diagnosis between pregnancy and trophoblastic tumours. To characterize the properties of hCG from the urine of choriocarcinoma patients, with or without the LcH affinity, hCG activities in both LcH-unbound and LcH-bound fractions were measured by in vivo and in vitro bioassays and each of the activities was compared with the activities measured by radioimmunoassay. The results showed that the LcH-unbound fraction contained hCG molecules defecting to induce the biological activity of hCG in vivo.

Animals↗
PubMed1986

A human-mouse hybridoma producing monoclonal antibody against human sperm coating antigen.

Since anti-sperm antibodies were first discovered in the sera of women, the relationship of these antibodies to sterility has been studied by many investigators. In order to determine the antigens of spermatozoa responsible for raising antibodies to spermatozoa in humans, many studies have been carried out by purifying human spermatozoa cell membrane and seminal plasma components. Since it was found that the purification was difficult by physiochemical procedures, the immunoaffinity chromatography bound monoclonal antibody (Mab) to spermatozoa antigens was attempted for this purpose. The establishment of hybridomas producing Mabs to human seminal plasma and human spermatozoa was reported by Shigeta et al. (1980), Isojima, Koyoma & Fujiwara (1982), Lee et al. (1982) and Isahakia & Alexander (1984). The ordinary approaches to obtain the Mabs consisted of xenogenic immunization with human semen and cell fusion of immunized spleen cells with mouse myeloma cells. However, the antigenic epitopes of human spermatozoa, which induced antibody production, are xenogenic for the mouse, and therefore there is a possibility that there is a difference in recognized antigenic epitopes in humans as isotypic and in mice as xenogenic. In order to study these antigenic epitopes, which correspond to antibodies against spermatozoa in women, the establishment of human-mouse hybridomas, which produced anti-semen antibodies as produced in sterile women, became essential. In these studies, we used recently developed cell fusion techniques to fuse immunized human peripheral lymphocytes with mouse myeloma cells.

Animals↗
PubMed1986

The development of a contraceptive vaccine by purification of antigens from gametes.

There are several ways to make immunological contraceptive vaccines. We are trying to purify gamete antigens from human seminal plasma and porcine zona pellucida (ZP) by using several monoclonal antibodies (Mabs) for this purpose. A human seminal antigen relevant to sperm immobilization with corresponding antibody was purified by immunoaffinity chromatography-bound Mab 1C4. This antigen was common to human milk protein but is different from lactoferrin. It was termed "ferrisplan" and was secreted mainly from the epithelial cells of seminal vesicle and adhered to the midpiece and postnuclear cap region of spermatozoa. Another Mab 2C6 reacted only to the SP component but not to other organ extract including human milk protein. The corresponding antigen to Mab 2C6 is aimed to purify by using high performance liquid chromatography and immunoaffinity chromatography-bound Mab 2C6. Several Mabs to porcine ZP antigens common to human ZP did not block human in vitro fertilization unless the second antibody (anti-mouse gamma-globulin) was used. It is speculated that porcine ZP will not contain the antigenic component that relates to sperm receptor of human ZP. Therefore, an antigenic molecule located close to sperm receptor of human ZP must be purified from the porcine ZP by using immunoaffinity chromatography-bound Mab and other biochemical methods, expecting production of a corresponding antibody that blocks the fertilization in humans.

Animals↗
PubMed1985

Production and characterization of monoclonal antibodies to cross-reactive antigens of human and porcine zonae pellucidae.

Three monoclonal antibodies (Mabs), 3A4-2G1, 1D5-2B7 and 1F2-1B8 were produced against heat-solubilized porcine zona pellucida (ZP). Each Mab stained intact ZP but no other pig tissues using immunofluorescence staining. All three Mabs stained selectively zonae pellucidae (ZPe) from pigs and humans but not from hamsters, rats or mice, and showed no inhibitory effect on sperm binding to human oocytes. When goat antiserum to mouse gamma-globulin was added to human oocytes pre-treated with 3A4-2G1 or 1D5-2B7, sperm binding to oocytes was completely blocked with formation of immune precipitates around them. SDS-PAGE analysis of the immune precipitates of 125I-labeled porcine zona proteins and Mab showed that the antigen binding 3A4-2G1 was mainly composed of components with approximate molecular weights of 92,000, 65,000 and 23,000 and the antigen binding 1D5-2B7 contained two components with approximate molecular weights of 57,000 and 49,000, respectively. The epitope of ZP antigen, corresponding to 3A4-2G1, was found to be present in the molecule of 92,000 daltons as demonstrated by enzyme immunostaining of the proteins after blotting to nitrocellulose membrane from SDS-PAGE gels.

Animals↗