scholarly journals Semen amyloids participate in spermatozoa selection and clearance

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Nadia R Roan ◽  
Nathallie Sandi-Monroy ◽  
Nargis Kohgadai ◽  
Shariq M Usmani ◽  
Katherine G Hamil ◽  
...  

Unlike other human biological fluids, semen contains multiple types of amyloid fibrils in the absence of disease. These fibrils enhance HIV infection by promoting viral fusion to cellular targets, but their natural function remained unknown. The similarities shared between HIV fusion to host cell and sperm fusion to oocyte led us to examine whether these fibrils promote fertilization. Surprisingly, the fibrils inhibited fertilization by immobilizing sperm. Interestingly, however, this immobilization facilitated uptake and clearance of sperm by macrophages, which are known to infiltrate the female reproductive tract (FRT) following semen exposure. In the presence of semen fibrils, damaged and apoptotic sperm were more rapidly phagocytosed than healthy ones, suggesting that deposition of semen fibrils in the lower FRT facilitates clearance of poor-quality sperm. Our findings suggest that amyloid fibrils in semen may play a role in reproduction by participating in sperm selection and facilitating the rapid removal of sperm antigens.

1997 ◽  
Vol 9 (1) ◽  
pp. 111 ◽  
Author(s):  
Mark P. Bradley ◽  
Lyn A. Hinds ◽  
Peter H. Bird

An orally-delivered immunocontraceptive vaccine is being developed for the control of fox populations. A number of genes (PH-20, LDH-C4, ZP3) encoding gamete proteins have been cloned, produced in recombinant expression systems and used in fertility trials to test the efficacy of these antigens. As the immunocontraceptive vaccine will be delivered in a bait, there is a requirement for a greater understanding of the immune responses of the reproductive mucosa in canids, and the assessment of the best vaccine delivery system that will evoke a mucosal antibody response. Several vaccine delivery systems including microencapsulated antigens, and both vaccinia virus and bacterial vectors are being investigated. Oral administration of Salmonella typhimurium recombinants expressing different fox sperm antigens stimulates both systemic IgG responses to the antigen and a mucosal immune response within the female reproductive tract in the fox, indicating that salmonella may have potential with respect to the oral delivery of antigen. The enhancement of mucosal immune responses to orally-delivered vaccines is also being examined, research focussing on the possible use of fox-specific cytokines or the β-subunit of cholera toxin in forming part of the vaccine construct.


2018 ◽  
Vol 4 (1) ◽  
pp. 132-136 ◽  
Author(s):  
Zafar Ahmed Bhuiyan ◽  
Md Giasuddin ◽  
Zahed Uddin Mahmood Khan

Infectious bronchitis virus (IBV) is a highly contagious viral disease of the chicken. It is possibly the most economically important viral respiratory disease of chicken after Avian Influenza and Newcastle disease. The virus also affects the female reproductive tract, causing poor quality of egg and loss of egg production. The study was conducted in four types of chicken (broiler, layer, sonali and Deshi) from 7 sub-districts under 4 districts of Bangladesh. Total 833 blood samples from 103 farms were collected and subjected to indirect ELISA test by commercially available IBV ELISA kits to detect specific antibodies against IBV. In overall 59.30% seroprevalence observed, 23.82% was found in broiler, 97.87% in layer, 71.83% in sonali and 83.46% in Deshi types of chickens. Broiler samples showed lowest seroprevalence with high CV (CV%=171.38), among them 76.18% were not seroconvert because of high maternal antibody or poor vaccine response. Layers showed highest seroprevalence with CV% 58.86 that is 18.00% chickens shows titer above 14000 which indicated field infection. Deshi chickens were not commercially vaccinated even though they had high seroprevalence rates 83.46% with mean titer 5333 and CV% 79.88, indicating that IBV is circulating as endemic diseases in the selected areas. Sonali chickens now reared as commercial chicken, have lower seroprevalence rates with mean titer 3160, CV% 128.39 indicating that these birds were not properly vaccinated as they required. To prevent the flocks from IBV, live and attenuated vaccination is required according to circulating strains.Asian J. Med. Biol. Res. March 2018, 4(1): 132-136


1968 ◽  
Vol 19 (5) ◽  
pp. 740-747 ◽  
Author(s):  
Seymour Katsh ◽  
Anthony Aguirre ◽  
Grace F. Katsh

Author(s):  
Mai M. Said ◽  
Ramesh K. Nayak ◽  
Randall E. McCoy

Burgos and Wislocki described changes in the mucosa of the guinea pig uterus, cervix and vagina during the estrous cycle investigated by transmission electron microscopy. More recently, Moghissi and Reame reported the effects of progestational agents on the human female reproductive tract. They found drooping and shortening of cilia in norgestrel and norethindrone- treated endometria. To the best of our knowledge, no studies concerning the effects of mestranol and norethindrone given concurrently on the three-dimensional surface features on the uterine mucosa of the guinea pig have been reported. The purpose of this study was to determine the effect of mestranol and norethindrone on surface ultrastructure of guinea pig uterus by SEM.Seventy eight animals were used in this study. They were allocated into two groups. Group 1 (20 animals) was injected intramuscularly 0.1 ml vegetable oil and served as controls.


Author(s):  
R.P. Apkarian ◽  
J.S. Sanfilippo

The synthetic androgen danazol, is an isoxazol derivative of ethisterone. It is utilized in the treatment of endometriosis, fibrocystic breast disease, and has a potential use as a contraceptive. A study was designed to evaluate the ultrastructural changes associated with danazol therapy in a rat model. The preliminary investigation of the distal segment of the rat uterine horn was undertaken as part of a larger study intended to elucidate the effects of danazol on the female reproductive tract.Cross-sections (2-3 mm in length) of the distal segment of the uterine horn from sixteen Sprague-Dawley rats were prepared for SEM. Ten rats in estrus served as controls and six danazol treated rats were noted to have alterations of the estrus cycle i.e. a lag in cycle phase or noncycling patterns. Specimens were fixed in 3% glutaraldehyde in 0.05M phosphate buffer containing CaCl2 at pH 7.0-7.4 and chilled to 4°C. After a brief wash in distilled water, specimens were passed through a graded series of ethanol, critical point dryed in CO2 from absolute ethanol, and coated with 6nm Au. Observations were made with an IS1-40 SEM operated at 15kV.


Author(s):  
Lawrence M. Roth

The female reproductive tract may be the site of a wide variety of benign and malignant tumors, as well as non-neoplastic tumor-like conditions, most of which can be diagnosed by light microscopic examination including special stains and more recently immunoperoxidase techniques. Nevertheless there are situations where ultrastructural examination can contribute substantially to an accurate and specific diagnosis. It is my opinion that electron microscopy can be of greatest benefit and is most cost effective when applied in conjunction with other methodologies. Thus, I have developed an approach which has proved useful for me and may have benefit for others. In cases where it is deemed of potential value, glutaraldehyde-fixed material is obtained at the time of frozen section or otherwise at operation. Coordination with the gynecologic oncologist is required in the latter situation. This material is processed and blocked and is available if a future need arises.


1966 ◽  
Vol 25 (2) ◽  
pp. 406-409 ◽  
Author(s):  
G. A. Schul ◽  
C. W. Foley ◽  
C. D. Heinze ◽  
R. E. Erb ◽  
R. B. Harrington

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