Biomedical subjects

I Kirman

Publications and source records attributed to I Kirman.

At least 19 recordsLinked to original sources

PubMed2006

Major surgical trauma induces proteolysis of insulin-like growth factor binding protein-3 in transgenic mice and is associated with a rapid increase in circulating levels of matrix metalloproteinase-9.

BACKGROUND: The authors previously demonstrated a significant decrease in plasma levels of intact insulin-like growth factor binding protein-3 (IGFBP-3) after major open but not after laparoscopic-assisted surgery in humans. They postulated that this decrease may have an effect on postoperative tumor growth. It also has been shown that plasma levels of matrix metalloproteinase-9 (MMP-9), a protease capable of degrading IGFBP-3, are transiently increased after open colectomy in humans. The authors aimed to develop an animal model that would allow further study of the effect that surgical trauma has on plasma levels IGFBP-3 and MMP-9. In addition, they set out to assess the concentration of MMP-9 in circulating monocytes before and after surgery. METHODS: The 30 mice included in this study were divided into three groups: sham laparotomy, carbon dioxide (CO2) pneumoperitoneum, and anesthesia control. All mice were IGFBP-3 transgenics (overexpressing human IGFBP-3) on a CD1 background. The mice were anesthetized using ketamine and xylazine. Blood was drawn retroorbitally 48 h before the procedure. The duration of the procedure was 30 min. The animals were killed 24 h postoperatively and blood was drawn. Intact IGFBP-3 levels were measured using a combination of Western blot analysis and enzyme-linked immunoassay (ELISA) at the two time points: before and after the operation. Plasma and peripheral blood mononuclear cell levels of MMP-9 were measured at each time point using zymography. Mononuclear cell lysates were used to determine intracellular MMP-9 levels. RESULTS: Plasma levels of intact IGFBP-3 were significantly lower than preoperative levels after sham laparotomy. A mean decrease of 76.6% was noted (p < 0.05). Zymography demonstrated significantly higher plasma MMP-9-related proteolytic activity than observed preoperatively after sham laparotomy (78.5 vs 42.3 Relative Units [RU]; p < 0.05). In the pneumoperitoneum group, no significant decrease was found between the pre- and postoperative levels of intact IGFBP-3. A nonsignificant increase in MMP-9 was noted after CO2 pneumoperitoneum (38 RU preoperatively vs. 46.4 RU postoperatively; p > 0.05). The anesthesia control group did not demonstrate a significant change in either circulating intact IGFBP-3 levels or MMP-9 levels. Mononuclear intracellular levels of MMP-9 were significantly lower after laparotomy than the preoperative levels (3 vs 37 RU). The postprocedure intracellular levels of MMP-9 were not significantly decreased in the pneumoperitoneum or anesthesia control group. CONCLUSION: Plasma levels of intact IGFBP-3, a cell growth regulating factor, were found to be decreased significantly after laparotomy. This decrease was not seen after pneumoperitoneum. Depletion of intact IGFBP-3 after laparotomy correlated with a rapid release of MMP-9 from mononuclear cells and an increase in circulating plasma MMP-9 levels. Matrix metalloproteinase-9 may play an important role in IGFBP-3 proteolysis after surgical trauma. Furthermore, circulating mononuclear cells are one source of MMP-9 after surgery. Finally, the model used reproduces events in humans after surgery, and thus should permit further study on the mechanism of IGFBP-3 proteolysis after surgical trauma.

Animals↗

PubMed2006

Altered plasma matrix metalloproteinase-9/tissue inhibitor of matrix [corrected] metalloproteinase-1 concentration during the early postoperative period in patients with colorectal cancer.

BACKGROUND: The authors have previously demonstrated that insulin-like growth factor binding protein-3 (IGFBP-3) is depleted in plasma for 1 to 3 days after major open surgery (OS), but not after laparoscopic surgery (LS). After surgery, IGFP-3 cleavage occurs rapidly and is likely attributable to altered plasma proteolytic activity. This study aimed to assess plasma proteolysis after both open and closed colorectal resection and, if possible, to identify a protease/protease inhibitor system affected by surgery. METHODS: Plasma from 88 patients with colorectal cancer (stages I-III) who underwent resection was obtained preoperatively (pre-OP) and on postoperative days (POD) 1 to 3. Plasma proteolytic activity was assessed via zymography. On the basis of the results, specific protease and protease inhibitor concentrations were next measured via enzyme-linked immunoassay (ELISA). Statistical analysis was performed using Wilcoxon's test. RESULTS: Early after surgery, zymography showed a predominant band representing a 92-kDa gelatinase corresponding to a proform of matrix metalloproteinase-9 (MMP-9), a protease known to cleave IGFBP-3. In OS patients, the mean concentration of plasma MMP-9 was significantly higher on POD 1 than at pre-OP (p < 0.003). On POD 2 and 3, no differences were noted. In the LS group, the mean levels of MMP-9 before and after surgery were comparable. The levels of a natural MMP-9 inhibitor, tissue inhibitor of metalloproteinase-1 (TIMP-1), also were measured. In the OS group, the level of TIMP-1 was significantly higher on POD 1 (p < 0.0003) and POD 2 (p < 0.01) and 3 (p < 0.01) than at pre-OP. In the LS group, a smaller but significant increase in TIMP-1 levels was found between the pre-OP sample and the POD 1 (p < 0.01) and POD 2 (p < 0.01) samples. No difference was noted on POD 3 (p = 0.1). CONCLUSIONS: Open surgery, but not laparoscopic surgery, is accompanied by a short-lived significant increase in MMP-9 levels, which likely accounts for the decrease in IGFBP-3 levels observed after OS. The transitory nature of MMP-9 imbalance may be attributable to the increase in TIMP-1 levels postoperatively.

Adenocarcinoma↗

PubMed2004

Open surgery induces a dramatic decrease in circulating intact IGFBP-3 in patients with colorectal cancer not seen with laparoscopic surgery.

BACKGROUND: As shown earlier by the authors via Western blot analysis, open (OS) but not laparoscopic surgery (LS) induces a qualitative decrease in plasma insulin-like growth factor-binding protein 3 (IGFBP-3) levels on postoperative day 1 (POD 1). Intact IGFBP-3 has tumor suppressive effects, but its degradation products do not. Enzyme linked immunoassay (ELISA) inevitably measures both. In this study, using a novel combined Western blot and ELISA analysis method, precise plasma levels of intact IGFBP-3 on POD2 after open and closed colorectal cancer resection (stage I-III) were determined. METHODS: This study included 15 OS patients with a mean incision length of 26.7 +/- 15.5 cm and 16 LS patients with a mean incision length of 5.3 +/- 3.1 cm. Intact IGFBP-3 levels were determined via ELISA and Western blot analysis in plasma collected preoperatively and postoperatively. RESULTS: In the OS patients, the mean preoperative concentration of intact 43-45 kDa IGFBP-3 protein was 1920 +/- 1430 ng/ml. It decreased dramatically on POD2 to 355 +/- 545 ng/ml (p < 0.005). In the LS group, no significant difference was noted between the preoperative level (1305 +/- 807 ng/ml) and the POD2 level (922 + 714 ng/ml). CONCLUSIONS: Open cancer resection, unlike its minimally invasive alternative, induces a dramatic decrease in concentration of intact IGFBP-3, which may have important implications with regard to colon cancer recurrence.

Colorectal Neoplasms↗

PubMed2003

Addition of interleukin-12 to GA733 tumor protein vaccine leads to development of tumor protective immunity despite surgical stress.

BACKGROUND: We have previously shown that preoperative vaccination with the GA733 protein does not inhibit tumor growth in mice undergoing open surgery or carbon dioxide insufflation. In this study we assessed the antitumor effect of a combined GA733 and interleukin-12 (IL-12) vaccine. METHODS: For this study, BALB/c mice were immunized with GA733, IL-12, or GA733 and IL-12, or they received no vaccine. Immediately after surgery (laparotomy or insufflation), GA733-transfected CT26 cells (C26-GA733) were injected subcutaneously into all mice. After 5 weeks, the mice were sacrificed, their tumors measured, GA733-specific antibodies determined by enzyme-linked immunoassay, and GA-733-specific cytotoxicity tested by flow cytometry using labeled C26-GA733 cells. RESULTS: Tumors were significantly (p < 0.05) smaller in both the insufflation and open groups that received combined GA733 and IL-12 than in their respective control subjects. Vaccination also induced a significant increase in the antibody and cell-mediated tumor-specific immunity. CONCLUSION: A preoperative vaccine consisting of GA733 and IL-12 inhibited postoperative tumor growth after open and closed surgery and allowed the mice to overcome the immunosuppressive effects of surgery.

Adjuvants, Immunologic↗

PubMed2003

The percentage of CD31+ T cells decreases after open but not laparoscopic surgery.

BACKGROUND: Efficient killing of tumor cells depends on T cells that migrate from the circulation to the peripheral tissues; these cells express CD31. This study was undertaken to determine the impact of open (OS) and laparoscopic (LS) colorectal surgery on the percentage of circulating CD3+CD31+ cells. METHODS: Peripheral blood was collected from 27 OS and 24 LS colon cancer patients preoperatively (preOP) and on postoperative days 1 (POD1) and 3 (POD3). CD31+ T cells were assessed by flow cytometry using monoclonal antibodies. RESULTS: In the OS group, the percentage of CD3+CD31+ cells was significantly lower in POD1 and POD3 samples compared to the preOP results. LS surgery did not result in a significant change in the percentage of these T cells. A significant correlation was found between the decrease in the percentage of CD3+CD31+ cells and the length of incision in OS patients. CONCLUSIONS: The percentage of CD3+CD31+ cells decreases following OS but not LS and may be related to incision length. This may compromise T cell function in the peripheral tissues in the postoperative period.

Adolescent↗

PubMed2003

Upregulation of interleukin-12 and -17 in active inflammatory bowel disease.

BACKGROUND: Cytokines are essential mediators of the intestinal inflammation during active episodes of inflammatory bowel disease (IBD). Interleukin (IL)-12 and IL-17 are potent immunoregulatory cytokines whose roles in the pathogenesis of IBD are unknown. The aim of this study was to evaluate the colonic expression of IL-12 and IL-17 genes in IBD. METHODS: Fifty-one patients (22 with ulcerative colitis (UC), 17 with Crohn disease (CD), and 12 controls) who underwent colonoscopy were included. IBD disease activity was determined using a clinical grading scale. The degree of inflammation, as well as the content of CD4+ T cells (synthesizing IL-17) and CD68+ macrophages (synthesizing IL-12) in colonic biopsies, was determined. The amounts of IL-12 and IL-17 mRNA were assessed by RT-PCR, using GAPDH as an internal standard. RESULTS: In colonic specimens, IL-17 mRNA expression was increased in moderately and severely active UC (P = 0.03) and in all degrees of activity in CD (P < 0.04). Levels of IL-12 mRNA were upregulated in both active UC and active CD compared to controls (P < 0.02). In cases of remission, IL-12 mRNA expression was similar to that found in control samples. Compared to controls, histological examination showed significant differences in signs of chronic and acute inflammation in UC (P < 0.01) and CD (P < 0.02), revealing a high correlation between clinical disease activity and histological scoring (r2 = 0.92, P < 0.005). Whereas CD4+ T cells were observed in lymphocyte aggregates located profound in the lamina propria, CD68+ macrophages were primarily found just underneath the surface epithelium. The density of CD4+ and CD68+ cells correlated significantly with the amounts of IL-17 and IL-12 mRNA, respectively (P < 0.05). CONCLUSION: The expression of both IL-12 and IL-17 mRNA is induced in active UC and CD and may thus be involved in sustaining the intestinal inflammation in IBD. Inhibition of IL-12 or IL-17 might be future therapeutic targets in IBD.

Adult↗

PubMed2002

Effect of surgical trauma on epithelial cell adhesion molecule (GA-733) vaccine-induced tumor resistance.

BACKGROUND: Surgical trauma inhibits immune function. Our goal was to study the effect of surgical intervention on the development of the immune response to epithelial cell adhesion molecule (EpCAM [GA-733]), a tumor-associated protein used for vaccination in colon cancer. METHODS: Recombinant GA-733 and monophosphoryl-lipid A (MPLA) were incorporated into biodegradable beads and implanted in the following groups of mice: control, insufflation, and laparotomy. After surgery, the mice were inoculated with GA-733-transfected C26 cells (C26-EpCAM). Plasma anti-GA733 IgG antibodies were detected in enzyme-linked immunoassay (ELISA). Killing specific to GA-733 was assayed by C26-EpCAM-killing assay. RESULTS: The difference in tumor size between immunized and nonimmunized animals was statistically significant only in control mice (p < 0.05). Greater cytotoxic response to C26-GA733 developed in all immunized mice groups than in their respective controls. However, anti-GA733 IgG increased significantly in the control and insufflation groups, but not in the laparotomy group. CONCLUSIONS: Combined GA-733 vaccine allows reduction of tumor growth in control but not in surgically managed animals. This vaccine can induce a specific-cell and antibody-mediated immune response. Open surgery leads to a decreased antibody response to the GA-733 tumor vaccine.

Adjuvants, Immunologic↗

PubMed2001

Combined whole tumor cell and monophosphoryl lipid A vaccine improved by encapsulation in murine colorectal cancer.

BACKGROUND: Whole autologous colon cancer vaccines in combination with various adjuvants have been used in both animals and humans. At this writing, vaccine regimens have been initiated in humans 3 to 6 weeks postoperatively. This delay between tumor resection and vaccination gives surviving tumor cells an opportunity to establish themselves. Vaccine administered either preoperatively or immediately after surgery, in theory, should be more effective. However, surgery-related immunosuppression may diminish the effectiveness of pre-operative or early postoperative vaccines. This problem may be overcome by limiting postoperative immunosuppression via the use of minimally invasive methods. Alternatively, the impact of the vaccine may be improved by encapsulating the vaccine, plus adjuvant, which in theory, should extend exposure time. Encapsulation of cancer vaccines in polysaccharide particles has not yet been studied. The goal of this study was to determine whether vaccine encapsulation, preoperative vaccination, and early postoperative vaccination affected the tumor burden. In addition, laparotomy and carbon dioxide insufflation were compared. METHODS: Vaccine was prepared from ultraviolet-irradiated C26 colon cancer cells in combination with monophosphoryl lipid A, either in suspension or entrapped in alginate beads. The C26 cell line and syngeneic BALB/c mice were used for all the studies. Tumor volumes were determined after excision of the tumors 2 weeks after inoculation in these studies. RESULTS: Encapsulated vaccine was more effective than the standard liquid vaccine. Significantly smaller tumors were noted in mice receiving encapsulated vaccine than in either the control group (p <0.01) or the liquid vaccine group (p <0.05). The use of a preoperative encapsulated vaccine was associated with significantly smaller tumors after laparotomy, pneumoperitoneum, or anesthesia alone when the tumors were established immediately after surgery. With an already established tumor, encapsulated vaccine, when given in the early postoperative period to mice that had undergone laparotomy or anesthesia alone was associated with significantly smaller tumors that those found in control animals. CONCLUSIONS: The incorporation of a whole-cell vaccine and monophosphoryl lipid A into alginate beads increases the efficacy of pre-operative and early postoperative tumor vaccines in the setting of both laparotomy and Carbon dioxide pneumoperitoneum. The use of perioperative vaccines may prove to be an effective way to immunize patients with cancer undergoing surgery.

Adenocarcinoma↗

PubMed2000

Colonic expression and synthesis of interleukin 13 and interleukin 15 in inflammatory bowel disease.

UNLABELLED: A dysregulated local immune reaction with unbalanced cytokine expression seems essential in inflammatory bowel disease (IBD), i.e. ulcerative colitis (UC) and Crohn's disease (CD). Since the roles of interleukin (IL-)13 and IL-15 remain unclear, this study aimed at studying intestinal expression of IL-13 and IL-15 in IBD. METHODS: In colonic biopsies from 24 UC, 18 CD, and 12 controls IL-13 and IL-15 were measured using ELISA, and their gene expressions were assessed by RT-PCR. Leukocytes were visualised histochemically. RESULTS: Concentrations of IL-13 were decreased in UC (median 56 pg/mg tissue; interquartile range 30-99 pg/mg) compared to CD (82 pg/mg tissue; 41-122;P=0.004) and controls (83 pg/mg tissue; 18-134;P>0.05), and lower in active UC (53 pg/mg tissue; 33-96) than in inactive UC (80 pg/mg tissue; 65-99;P=0.02). IL-15 concentrations were higher in CD patients (34 pg/mg tissue; 24-53) as compared to controls (20 pg/mg tissue; 15-21;P=0.001) whilst being 22 pg/mg tissue (15-32) in UC. IL-13 mRNA and IL-15 mRNA were detected in 20% and 15%, respectively. Infiltration of leukocytes correlated inversely with IL-13 levels (P=0.02). CONCLUSION: Active UC is associated with decreased colonic IL-13 suggesting that IL-13 levels are diminished as a part of UC exacerbations, or that exacerbations follow active downregulation of IL-13.

Adult↗

PubMed2000

Assessment of the degradation of denatured albumin solder by human urine.

PURPOSE: Several studies have been undertaken to evaluate the efficacy of human serum albumin (HSA) as a solder in urologic procedures. The purpose of this study was to evaluate whether albumin solder undergoes significant degradation in urine. MATERIALS AND METHODS: Laser denatured 25% HSA pellets were incubated at 37C for varying times with 1 ml. of either pooled human urine or control diluent solution adjusted to the same pH and osmolality as urine. To assess the contribution of enzymatic degradation, aliquots of urine were boiled and compared with non-boiled urine and diluent. The amount of solubilized HSA in solution was measured using the Bradford assay, while the degradation of albumin was detected by SDS-PAGE electrophoresis. RESULTS: Approximately 5% of the albumin was degraded over a period of 7 days following incubation at 37C, regardless of treatment. SDS-PAGE revealed only minor traces of degradation in urine and controls. The very slight degradation of denatured HSA appears to be non-enzymatic, as it was observed in both urine and diluent samples. CONCLUSIONS: HSA solder appears to be appropriate for use in urologic reconstructive surgery since it is not appreciably degraded in the presence of urine.

Albumins↗

PubMed2000

Interaction of nitric oxide and transforming growth factor-beta1 induced by angiotensin II and mechanical stretch in rat renal tubular epithelial cells.

PURPOSE: Changes in intrarenal pressure accompanying unilateral ureteral obstruction can result in tubular mechanical stretch and mediator release from renal tubules. Therefore, we examined the synthesis of nitric oxide and transforming growth factor-beta (TGF-beta), and their interaction in rat renal epithelial cells (NRK-52E) exposed to either angiotensin II or mechanical stretch. MATERIALS AND METHODS: NRK-52E were exposed to either angiotensin II or mechanical stretch. Nitrite and TGF-beta in the supernatant were assessed by the Greiss reaction and bioassay, respectively. The level of cell hypertrophy and intracellular TGF-beta protein was determined by flow cytometry. TGF-beta messenger RNA and inducible nitric oxide synthase protein were detected by reverse transcriptase polymerase chain reaction and Western blot, respectively. RESULTS: Angiotensin II stimulated TGF-beta1 and nitric oxide. The nitric oxide synthase inhibitor, N-nitro-L-arginine (L-NAME) or angiotensin II type I receptor blocker, losartan, inhibited nitric oxide and TGF-beta1 induced by angiotensin II. Flow cytometry showed that either L-NAME or losartan inhibited angiotensin II induced cell hypertrophy. TGF-beta1 inhibited iNOS protein and nitric oxide, whereas an anti-TGF-beta antibody enhanced iNOS. Mechanical stretch induced TGF-beta, inducible NOS protein and nitric oxide. However, TGF-beta expression was not affected by L-arginine or L-NAME when cells were exposed to mechanical stretch. CONCLUSIONS: These results demonstrate that nitric oxide is an intermediate in angiotensin II stimulated TGF-beta1 expression but not in stretch induced TGF-beta expression, and that TGF-beta1 is a negative regulator of nitric oxide in rat renal epithelial cells. The complex interaction of these cytokines may be a target for intervention in the fibrotic and apoptotic processes in the obstructed kidney.

Angiotensin II↗

PubMed1999

Effect of laser welding with human serum albumin on the expression of P-selectin on platelets.

BACKGROUND AND OBJECTIVE: Artery repair by means of laser energy induces activation of platelets with a risk of thrombosis and local inflammatory reactions. The aim of this study was to investigate the effect of human serum albumin, the most common solder in laser surgery, on platelet activation. STUDY DESIGN/MATERIALS AND METHODS: Platelet activation was evaluated in canine blood by using two-color flow cytometry with a phycoerythrin-labeled antibody to a common platelet marker, glycoprotein IIb/IIIa and fluorescein isothiocyanate-labeled antibody to a platelet activation molecule, P-selectin. Human serum albumin was applied in vitro and in vivo, as a solder during laser reconstruction of canine arteries. RESULTS: In vitro, albumin significantly (P < 0.01) reduces the expression of P-selectin on platelets. This is most likely related to the blockage of P-selectin by albumin, which binds to the platelet surface, as confirmed by flow cytometry with fluorescein isothiocyanate-labeled albumin. In vivo, application of albumin solder tended to result in a lower percentage of P-selectin-expressing platelets in laser-repaired arteries compared to suture-repaired arteries. CONCLUSION: Albumin decreases the percentage of P-selectin-expressing platelets in vitro. Further research may allow the platelet activation inhibiting properties of albumin to be further optimized in vivo.

Animals↗

PubMed1998

Maturation of B cell precursors is impaired in thymic-deprived nude and old mice.

We have previously reported that bone marrow B cell precursors from thymic-deprived nude and old mice express less recombination-activating gene-1 (RAG-1) mRNA than they do in young euthymic mice. We now report that both nude and old mice have decreased bone marrow pre-B cells and that fewer pre-B cells express RAG protein. This combination of events appears to be the basis for the lower level of bone marrow RAG mRNA in thymic-deprived mice. A link between thymic function and B cell development was suggested by the similar kinetics of thymic involution and of declining bone marrow RAG-1 gene expression during aging. Support for this hypothesis was obtained by demonstrating that injection of supernatant medium from activated CD8+ but not CD4+ young T cells from mice increases RAG mRNA, RAG protein, and the number of bone marrow pre-B cells in nude and old mice. Furthermore, in vivo CD8+ T cells also regulate bone marrow RAG gene expression. Thus, mice deficient in CD8+ T cells expressed levels of RAG-1 mRNA in their bone marrow that were only 10% of those observed in normal or CD4+ T cell-deficient mice. IL-16 was detected in the supernatant medium from activated T cell cultures, and injection of nanogram quantities of recombinant IL-16 (rIL-16) into nude or old mice increased the levels of RAG mRNA in bone marrow B cell precursors and the number of bone marrow pre-B cells. We conclude that the impaired development of B cells within the bone marrow of thymic-deprived nude and old mice can be reversed, at least in part, by the administration of rIL-16.

Aging↗

PubMed1998

Interleukin-15 and its role in chronic inflammatory diseases.

This review focuses on the biological effects of the newly discovered cytokine, interleukin 15 (IL-15), in chronic inflammatory disorders. IL-15 shares biological activities with IL-2, and like IL-2 it is a member of the four-helix bundle cytokine family. IL-15 interacts with a heterotrimeric receptor that consists of the beta and gamma subunits of the IL-2 receptor (IL-2R) as well as a specific, high-affinity IL-15-binding subunit, IL-1SRalpha. IL-15 is produced by macrophages and various other cells in response to environmental stimuli and infectious agents, and it is important for the growth and differentiation of T and B lymphocytes, natural killer cells, macrophages, and monocytes as well as it activates a number of important intracellular signaling molecules, including the Janus kinases and members of the transcription factor family of signal transducers and activators of transcription. These facts suggest that IL- 15 may play a pivotal role both in protective immune responses and in the pathogenesis of various chronic immuno-inflammatory disorders. The important new insight into the role of IL-15 in diseases such as rheumatoid arthritis, sarcoidosis, chronic hepatitis C, and ulcerative colitis are reviewed in this paper.

Animals↗

PubMed1998

Sex-selection of human spermatozoa: evolution of current techniques and applications.

Methods claiming to achieve sex selection by sperm sorting have existed for many years. Numerous applications for safe and effective selection procedures exist in current clinical practice, as sex-linked conditions could be theoretically eliminated by use of appropriate sperm for fertilization or insemination. Use of such techniques could also address the need to effect family balancing for some couples. Modern preconception sex-selection methods may be classified into two general types: those that attempt to segregate spermatozoa on the basis of subtle physical or kinetic features, and those that rely on distinctive nuclear characteristics unique either to X- or Y-chromosome bearing sperm. Laboratories providing sperm sexing using the former method have been available for some years, although the associated efficiency and reproducibility are controversial. Sex selection of spermatozoa by chromatin differences has been shown to achieve significant enrichment of X- or Y-chromosome bearing sperm, but clinical experience in humans is limited. The fundamental elements of the two approaches introduced here are reviewed and compared. Selected key historical concepts in sex selection by sperm sorting are outlined, followed by a summary of promising areas for future research.

Centrifugation, Density Gradient↗

PubMed1998

Increased apoptosis of bone marrow pre-B cells in old mice associated with their low number.

The number of bone marrow pre-B cells is significantly lower in 18- than in 2-month-old BALB/c mice. The percentage of apoptotic pre-B cells, freshly isolated or cultured, from 18-month-old mice was significantly greater than from 2-month-old mice. The increased percentage of apoptotic pre-B cells from old mice was associated with a decreased level of bcl-xL mRNA, detected by RT-PCR, and of Bcl-xL protein, detected by intracellular staining. Consistent with an age-associated increase in apoptosis in pre-B cells was the fact that significantly fewer pre-B cells were generated after in vitro cultures of pro-B cells from old as compared to young mice. Furthermore, fewer pre-B cells survived and fewer sIg-expressing B cells were generated in cultures of pre-B cells from old as compared to young mice. In addition, there was no detectable difference in the secretion of IL-7 by bone marrow cells from 2- or 18-month-old mice. Thus, increased apoptosis of bone marrow pre-B cells in old mice appears to contribute to their decreased number.

Aging↗

PubMed1998

The circulating common gamma chain (CD132) in inflammatory bowel disease.

OBJECTIVE: Inflammatory bowel disease (IBD) is characterized by T cell activation. Activated T cells shed interleukin-2 receptors (IL-2R) in a soluble form. A positive correlation between sIL-2Ralpha (CD25) and disease activity is well documented in IBD, whereas IL-2Rgamma (CD132) has not been investigated in this respect. Sera from 42 patients with ulcerative colitis (UC), 34 with Crohn's disease (CD), 31 healthy volunteers, and 12 patients with infectious enterocolitis were obtained. METHODS: Disease activity was scored according to a semiquantitative score for UC and CD. sIL-2R alpha chain and gamma chain were assessed by sandwich ELISA techniques using monoclonal antibodies specific for CD25 and CD132, respectively. RESULTS: The concentration of IL-2Ralpha chain (CD25) was found to be median 3.8 ng/ml in healthy volunteers versus 7.0 ng/ml in UC patients (p < 0.001), and 9.6 ng/ml in CD patients (p < 0.001). With respect to IL-2Rgamma (CD132), significantly higher amounts were found in CD patients: 6.6 ng/ml as compared with healthy controls <1.0 ng/ml (p < 0.004). A Kruskal-Wallis test revealed a significant correlation between alpha chain and disease activity in CD (p < 0.001), and further significantly higher gamma chain levels were found in active CD (p = 0.03). For UC patients, a statistically significant increase of the alpha chain with increasing disease activity (p < 0.01) was observed, whereas no significant changes of the gamma chain levels were found (p > 0.05). A difference of gamma chain levels were found between CD and UC in moderate and severe disease activity (p < 0.05). Further analyses revealed that mesalazine did not influence the IL-2Ralpha or -gamma concentration either in UC or in CD patients. CONCLUSION: An increased circulating level of the soluble common gamma chain (CD132) seems to be found in CD, and an overlap exists between CD and UC.

Adult↗

PubMed1998

H-Y antigen expression patterns in human X- and Y-chromosome-bearing spermatozoa.

PROBLEM: Restricted expression of H-Y antigen on Y-chromosome-bearing sperm has been reported in some species, although such preferential expression for H-Y antigen in human sperm has yet to be described. In this study, an immunomagnetic approach was used to characterize antigen expression patterns as a function of sex-chromosome content. METHOD OF STUDY: Human sperm was treated with monoclonal immunoglobulin (Ig) M antibodies directed against H-Y antigen. This preparation then was incubated with sheep antimouse IgM antibody affixed to paramagnetic beads, which then were exposed to a magnetic field and sorted. X- and Y-chromosome frequencies in the two subgroups of sperm were assayed by multiprobe fluorescent in situ hybridization (FISH). RESULTS: Sperm were immunomagnetically separated into two populations: a reactive group (presumably, H-Y Ag+); and a nonreactive group (presumably, H-Y Ag-). Triple-color FISH analysis of 1,600 spermatozoa (800 in each group) showed the antigen's expression to be somewhat more prevalent among Y-chromosome-bearing sperm (54.1%), but a large proportion of Y-chromosome-bearing sperm (49.0%) did not express this antigen. The difference was not significant (P = 0.43). CONCLUSIONS: The expression of H-Y antigen has a slightly higher frequency in human sperm containing the Y-chromosome, but its expression among X-chromosome-bearing sperm also is considerable. Current immunologic techniques relying on this antigen are unlikely to effect the sex selection of human sperm.

Animals↗