Search

Objectives: Our aims were to determine immunoglobulin and cytokine levels in cervical mucus obtained from women during each trimester of pregnancy and to compare these levels with those reported in normally menstruating women and in women taking oral contraceptives., Study Design: Cervical mucus samples were collected at specified intervals from 36 pregnant women. An enzyme-linked immunosorbent assay was used to quantitate the presence of immunoglobulins A and G and interleukins 1 beta, 6, and 10 in cervical mucus., Results: Immunoglobulin A in cervical mucus remained stable during each trimester of pregnancy (26 mg/dL). Cervical mucus immunoglobulin G decreased from a first-trimester high of 44.4 mg/dL to lower levels in the second and third trimesters. Levels of interleukin 1 beta increased significantly from the first trimester (4261 pg/mL) to 12,899 pg/mL in the second trimester (P <.01)., Conclusion: These data suggest a possible correlation of reproductive hormones and immunologic factors in the female reproductive tract during pregnancy.

Mucosal immunity in the female reproductive tract is influenced by immunoglobulins (Igs), cytokines, and reproductive hormones. Previous studies of reproductive-aged women demonstrated that IgA and IgG increases in cervical mucus corresponded to elevated levels of IL-1beta which occurred 1 day before the peak of endogenous estradiol production prior to ovulation. We sought to determine the effect of exogenous hormones on reproductive tract immunity in women on oral contraceptive pills (OCPs) and to compare the results with respect to naturally cycling women. Twelve women of reproductive age who had negative cervical cultures, a normal pap smear, and agreed to abstain from sexual intercourse during the study initiated OCPs. Cervical mucus and vaginal washes were collected at six intervals (2-3 days apart) throughout the treatment cycle. Fifteen naturally cycling women had similar samples collected prior to, during, and subsequent to ovulation. Cervical mucus samples were assayed for IgA, IgG, IL-1beta, IL-6, and IL-10 by enzyme-linked immunosorbent assay (ELISA). IgA, IgG and IL-1beta levels in women on OCPs paralleled increasing levels of norethindrone. Mean values of IgA increased from a low of 14.4+/-3.1 to 41.1+/-9.4 mg/dl and decreased significantly after the cessation of the pills (P < 0.001). In naturally cycling women, the largest quantities of Igs were detected prior to ovulation. By comparison, mean values of IgA in the cervical mucus of women on OCPs (24.4 mg/dl) exceeded peak levels of IgA in the cervical mucus of naturally cycling women (14.6 mg/dl). IgA was the predominant Ig detected in cervical mucus of women on OCPs. Both immunoglobulins in each group exhibited changes relative to their hormonal status. The increased levels of IgA in the cervical mucus of women on OCPs may explain the clinical observation of a lower incidence of sexually transmitted diseases.

Mucosal surfaces serve as the portal of entry for many viral, bacterial, and parasitic infections. Understanding the immunity at mucosal membranes is essential to enhancing protection and decreasing infections. To evaluate the humoral and cellular immunity in the female reproductive tract, 15 reproductive-age women with a history of regular, cyclic monthly menses were recruited for this study. The presence of immunoglobulins and cytokines in cervical mucus was correlated with the production of reproductive hormones in sera. Cervical mucus specimens were collected at each daily visit beginning on cycle day 8 and continuing for 5 days postovulation. Volunteers were monitored by daily urinary LH testing coupled with transvaginal ultrasonography to ascertain follicular collapse. The cervix was washed in sterile saline before aspirating the cervical mucus from the cervical canal. Collection volumes ranged between 50 and 800 microl and were considered to represent the total mucus produced. Estradiol displayed the characteristic biphasic pattern with a peak before ovulation and in the luteal phase. Both IgG (30 mg/dl) and IgA (15 mg/dl) had a biphasic pattern with peak immunoglobulin levels detected 1 day before the estradiol peak and increasing again just after ovulation. Peak interleukin 10 (40 pg/ml) levels corresponded precisely with estradiol peak levels just before ovulation. Peak interleukin 1beta (1.3 ng/ml) levels occurred approximately 1 day before the estradiol peak. No apparent pattern in interleukin 6 (150 pg/ml) could be ascertained. Our data suggest a correlation between the IgG and IgA immunoglobulin levels, interleukin 1beta and interleukin 10, in the female reproductive tract and estradiol levels in the circulation. The increase in immunoglobulins and cytokines occurs approximately 1 day before the peak estradiol production before ovulation. These data suggest a role for cytokines and hormones in the regulation of reproductive tract immunity.

The quantity and subclass distribution of IgA produced by the human uterine cervix may have a significant impact on the defence against sexually transmitted diseases as well as the regulation of fertility. Cervical mucus was obtained from 15 normal ovulating women around the time of ovulation. The total amounts of secreted IgA (including IgA1 and IgA2), IgG, and IgM were determined by ELISA. IgA was detected at high levels in all samples of cervical mucus. When ovulation was ascertained by daily urinary luteinizing hormone testing, IgA production was maximal 2-3 days before ovulation. Equal proportions of IgA1 and IgA2 were detected in cervical mucus, and 80% of the IgA occurred in the polymeric forms. The increased levels of IgA, the ratios of IgA1 to IgA2, and the predominance of polymeric IgA indicate that much of the IgA in human uterine cervical fluid originates from local production.

Objective: To determine the immunoglobulin (Ig) A subclass distribution of antibodies in the serum and cervical mucus (CM) of infertile women and to evaluate the effect of an IgA1 protease on the removal of sperm-bound antibodies., Methods: Twenty infertile women with antisperm antibodies in serum (n = 10) or in CM (n = 10) were recruited for this study. Monoclonal antibodies to human IgA1 and IgA2 were conjugated to immunobeads and the IgA subclass distribution of antisperm antibodies was determined for positive serum and CM samples. The effect of an IgA1 protease (isolated from Neisseria meningitidis strain HF13) on sperm-bound antibodies was evaluated by immunobead binding., Results: In serum, IgA1 subclass antisperm antibodies predominated (89%) when compared to IgA2 (11%). In CM IgA1 accounted for 62% and IgA2 accounted for 38% of the total IgA antisperm antibodies. Enzyme treatment was able to reduce dramatically the amount of serum IgA antibodies bound to sperm from 88% to 10%. Similarly, a significant reduction in CM antisperm antibodies was observed after enzymatic treatment with no loss in sperm motility., Conclusion: Cervical mucus antisperm antibodies have a higher proportion of IgA2 subclass suggesting a local production of IgA. Specific IgA1 protease treatment is capable of reducing the amount of immunobead-detectable IgA on sperm. Hamster sperm penetration assays are ongoing to determine if this treatment might improve sperm penetration rates with antibody positive sperm.

Problem: (1) To determine the IgA subclass distribution of antibodies in the serum and on the sperm of infertile male patients. (2) To determine the effect of an IgA1 protease on the binding of IgA antisperm antibodies (ASA)., Method: Fifteen infertile males with ASA in serum (10) or on sperm (5) were recruited for this study. Duration of infertility was at least one year. Monoclonal antibodies to human IgA1 and IgA2 were conjugated to immunobeads. The distribution of IgA1 and IgA2 subclass ASA was determined for positive serum and sperm samples. The effects of an IgA1 protease (isolated from Neisseria meningitidis strain HF13) on sperm-bound antibodies was evaluated by immunobead binding., Results: In serum, the IgA1 subclass ASA was predominate (91%) when compared with IgA2 (9%) subclass. Direct sperm-bound antibodies displayed a distribution more characteristic of the secretory immune system with IgA1 accounting for 63% and IgA2 accounting for 37% of the total IgA ASA. Enzyme treatment dramatically reduced the amount of serum IgA antibodies bound to sperm (P < 0.05). Similarly, a significant reduction in direct sperm-bound antibodies was observed after enzymatic treatment with no loss in sperm motility., Conclusions: (1) Although IgA1 direct sperm-bound antibodies were dominant, when compared with serum there was a higher proportion of IgA2 subclass, which suggests a local production of IgA. (2) Specific IgA1 protease treatment is capable of reducing the amount of immunobead-detectable IgA on sperm. Hamster oocyte sperm-penetration assays are ongoing to determine if this treatment might improve sperm penetration rates.

In comparison with normal individuals, sera of patients with alcoholic cirrhosis and other liver diseases had two to four times higher levels of immunoglobulin A and three to ten time higher levels of polymeric immunoglobulin A. The possible participation of the liver in the selective removal of polymeric immunoglobulin A from serum into bile was investigated by analyzing immunoglobulin A in serum and bile specimens obtained from a group of patients with T-tube drainage of the common bile duct. Gel filtration revealed three principal fractions of biliary immunoglobulin A: secretory immunoglobulin A with J chain and secretory component; polymeric immunoglobulin A associated with J chain; and monomeric immunoglobulin A devoid of J chain and secretory component. Secretory component-complexed immunoglobulin A composed only 50% or less of the total biliary immunoglobulin A. In comparison with immunoglobulin G, polymeric forms of immunoglobulin A appeared to be selectively transported into bile whereas monomeric immunoglobulin A was not. These data suggested that the liver selectively transports polymeric immunoglobulin A from serum into bile by both secretory component-dependent and -independent mechanisms.

Human tissues were examined for their ability to produce monomeric and polymeric forms of IgA in vitro. Mononuclear cells were examined for the presence of cytoplasmic immunoglobulins and J chain (by immunofluorescence) and for the amounts and molecular forms of intracellular and secreted IgA (by radioimmunoassay). Cultured bone marrow cells were the largest producers of total IgA, and approximately 90% of the secreted IgA was monomeric. Spleen cells also produced predominantly monomeric IgA. Intestinal lamina propria cells secreted the greatest amounts of polymeric IgA, but also produced significant amounts of monomeric IgA. Tonsillar, lymph node, and peripheral blood cells produced approximately equal proportions of monomeric and polymeric IgA. These results suggested that bone marrow may be a major source of serum monomeric IgA, and that lymphoid tissues associated with secretory surfaces may provide a greater proportion of polymeric IgA than other lymphoid tissues. There was a positive correlation between the production of polymeric IgA and the presence of cytoplasmic J chain; tissues that produced predominantly monomeric IgA generally displayed fewer cells containing cytoplasmic J chain.

Human peripheral blood lymphocytes (PBL) were cultured for various time periods (up to 8 d) in the presence of pokeweed mitogen (PWM), lipopolysaccharide, or Epstein-Barr virus. Cell-free supernates were fractionated on a standardized ultrogel AcA 22 column and the proportion of polymeric and monomeric IgA was determined by radioimmunoassay. The results demonstrate that PBL stimulated with these mitogens produce IgM and IgG with molecular characteristics identical to those found in serum, but that the IgA produced is predominantly of the polymeric type. To prove that this IgA represented disulfide bond-linked polymers rather than aggregated monomers, we have demonstrated that the high molecular weight IgA (a) maintains its polymeric form upon treatment with acidic buffers, (b) contains J chain, a glycoprotein associated only with polymeric immunoglobulins, and (c) dissociates to the monomeric form upon reduction of disulfide bonds. After 1 wk in culture, approximately 60% of the PWM-stimulated cells that contained IgA were positive for IgA2, whereas 40% were IgA1 positive as determined by immunofluorescence. Therefore, peripheral blood contains a population of lymphocytes with the potential to display, after appropriate stimulation and differentiation, characteristics similar to IgA cells found in external secretory tissues. The demonstration of the presence of such cells in the peripheral circulation suggests that these cells are precursors of IgA-producing plasma cells with the potential to populate mucosal tissues.