scholarly journals Natural Immunity to HIV: A Delicate Balance between Strength and Control

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Johanne Poudrier ◽  
Valérie Thibodeau ◽  
Michel Roger

Understanding how the mucosal immune system in the human female reproductive tract might prevent or facilitate HIV infection has important implications for the design of effective interventions. We and others have established cohorts of highly-exposed, HIV-seronegative individuals, such as HIV-uninfected commercial sex workers, who have remained HIV-negative after more than 5 years of active prostitution. Observations obtained in studies of such individuals, who represent a model of natural immunity to HIV, indicate that HIV resistance may be associated with the host’s capacity to preserve systemic integrity by constraining immune activity and controlling inflammatory conditions at the mucosal point of entry. This likely necessitates the orchestration of balanced, first-line and adaptive immune responses.

2011 ◽  
Vol 56 (No. 6) ◽  
pp. 279-283 ◽  
Author(s):  
A. Gümen ◽  
A. Keskin ◽  
G. Yilmazbas-Mecitoglu ◽  
E. Karakaya ◽  
S. Cevik ◽  
...  

In several studies, hormones such as gonadotropin-releasing hormone (GnRH), prostaglandins and oxytocin were used to increase pregnancy rate by inducing ovulation and improving the sperm transport in the female reproductive tract in lactating dairy cattle. The objective of this study was to compare the effects of GnRH, prostaglandin F<sub>2&alpha;</sub> (PGF<sub>2&alpha;</sub>) and oxytocin treatments at the time of artificial insemination (AI) after spontaneous oestrus on the conception rate (CR) of lactating dairy cows. Oestrus was detected by visual observations by experienced personnel. All cows (n = 430, 308 Holstein-Frisian and 122 Swedish-Red dairy cows) were inseminated based on the am/pm rule by veterinarians of the farm. After AI, cows were alternately assigned to one of the four treatment groups: (1) GnRH (n = 113); (2) PGF<sub>2&alpha;</sub> (n = 106);<br />(3) oxytocin (n = 106) and (4) non-treated control (n = 105). Pregnancy diagnosis was performed 28&ndash;34 and 58&ndash;64 days post-insemination by transrectal ultrasonography. Conception rates on days 28&ndash;34 and 58&ndash;64 were not different among GnRH (46.0%; 52/113 and 44.3%; 50/113), PGF<sub>2&alpha;</sub> (37.7%; 40/106 and 35.9%; 38/106) and control (49.5%; 52/105 and 47.6%; 50/105) groups. However, conception rates were lower (P = 0.02) in oxytocin (31.1%; 33/106 and 30.2%; 32/106) than in GnRH and control groups on days 28&ndash;34 and 58&ndash;64. Other covariant factors, such as milk production, days in milk (DIM), breed, parity, service number did not affect the conception rate. Thus, there were no beneficial effects of treatments with GnRH and PGF2&alpha; at the time of AI, and oxytocin had an adverse effect on CR in lactating dairy cows in this study.


Reproduction ◽  
2011 ◽  
Vol 141 (6) ◽  
pp. 725-735 ◽  
Author(s):  
Lorraine Frew ◽  
Sarah J Stock

Antimicrobial peptides (AMPs) are small proteins produced by epithelial surfaces and inflammatory cells, which have broad-spectrum antimicrobial and immunomodulatory activities. They are known to be important in a number of infectious and inflammatory conditions and have been shown to be present in a number of sites throughout the female reproductive tract. Inflammation and infection are associated with a number of complications of pregnancy including preterm labor, and AMPs may play a key role in maintaining and protecting pregnancy. The aim of this review is to describe the expression and function of AMPs in the pregnant female reproductive tract and their relation to preterm labor.


Reproduction ◽  
2001 ◽  
pp. 649-655 ◽  
Author(s):  
K Yoshinaga ◽  
DK Saxena ◽  
T Oh-oka ◽  
I Tanii ◽  
K Toshimori

The monoclonal antibody mMN9 recognizes an antigenic molecule, equatorin, which is localized at the equatorial segment of the mammalian sperm acrosome. Our previous results using an IVF system indicated that mMN9 blocked sperm-oocyte fusion. Antibody-containing and control solutions were injected directly into the right and left oviductal ampullae, respectively, of anaesthetized female mice to assess the effect of mMN9 on fertilization in vivo. After hCG treatment, the females were mated, and their oviductal eggs and implanted embryos were examined. mMN9 was retained in the oviductal lumen at 20 h after injection. The rates of fertilization and concomitant pregnancy were significantly lower than in the control side (P < 0.05). In addition, histological studies showed no evidence of pathological changes in the female reproductive tract after the injections. These results indicate that mMN9 inhibits mouse fertilization significantly under in vivo conditions and that this injection method should be useful for studying the effects of antibodies and agents on fertilization in vivo.


Parasitology ◽  
1983 ◽  
Vol 86 (4) ◽  
pp. 59-83 ◽  
Author(s):  
J. Riley

SUMMARYPentastomids are arthropod parasites which attain maturity in the respiratory tracts of vertebrates. All pentastomids exhibit an obvious sexual dimorphism in that fully mature females are invariably much bigger than males. Unusually though, copulation, which happens only once in the lifetime of females, occurs when both sexes are approximately the same size and the uterus of the female is undeveloped. This is because sperm is stored in spermathecae which, being positioned at the junction of the oviduct and uterus, become more remote from the vagina as the uterus elongates during development. The provision of spermathecae for sperm storage allows oocytes, shed continuously from the ovary, to be fertilized from time to time. What renders this process quite remarkable, and possibly unique, is the extreme length of the patent period. In one species this can extend up to an estimated 10 years and is associated with an egg production of about 106eggs/female/year. Spermathecal structure provides some clues as to how prolonged sperm storage and the continuous fertilization of oocytes is accomplished. The upper region of the access duct is a narrow, chitinized tube which tapers to as little as 3 μm diameter at the point of entry into the spermatheca. The chitinous (?) lining of the spermatheca is relatively impermeable and apparently functions to totally isolate sperm from external influences: stored sperm are arranged in bundles and whorls and remain totally quiescent and inactive during the storage period. The entire spermatheca is invested by muscle fibres, the contraction of which will express small numbers of sperms through the narrow access duct. These are then reactivated by secretions from the female reproductive tract: the extreme narrowness of the spermathecal duct provides the fine adjustment of the system. The narrowness of the duct also creates problems during the process of insemination, since sperm discharged directly into the female reproductive tract would be unlikely to find the spermatheca through such a structure. Accordingly, the male cirrus is much modified to directly penetrate the spermathecal duct during copulation. Sperms, stored in the male seminal vesicle, are apparently activated prior to sperm transfer, and swim along the cirrus to be guided directly into the spermathecal lumen. Some unusual variations on the normal pentastomid life-cycle are discussed.


2019 ◽  
Vol 20 (7) ◽  
pp. 1649 ◽  
Author(s):  
José Murrieta-Coxca ◽  
Sandra Rodríguez-Martínez ◽  
Mario Cancino-Diaz ◽  
Udo Markert ◽  
Rodolfo Favaro ◽  
...  

The IL-36 subfamily of cytokines has been recently described as part of the IL-1 superfamily. It comprises three pro-inflammatory agonists (IL-36α, IL-36β, and IL-36γ), their receptor (IL-36R), and one antagonist (IL-36Ra). Although expressed in a variety of cells, the biological relevance of IL-36 cytokines is most evident in the communication between epithelial cells, dendritic cells, and neutrophils, which constitute the common triad responsible for the initiation, maintenance, and expansion of inflammation. The immunological role of IL-36 cytokines was initially described in studies of psoriasis, but novel evidence demonstrates their involvement in further immune and inflammatory processes in physiological and pathological situations. Preliminary studies have reported a dynamic expression of IL-36 cytokines in the female reproductive tract throughout the menstrual cycle, as well as their association with the production of immune mediators and cellular recruitment in the vaginal microenvironment contributing to host defense. In pregnancy, alteration of the placental IL-36 axis has been reported upon infection and pre-eclampsia suggesting its pivotal role in the regulation of maternal immune responses. In this review, we summarize current knowledge regarding the regulatory mechanisms and biological actions of IL-36 cytokines, their participation in different inflammatory conditions, and the emerging data on their potential role in normal and complicated pregnancies.


2002 ◽  
Vol 76 (2) ◽  
pp. 143-155 ◽  
Author(s):  
M.S. Mobarak ◽  
M.F. Ryan

AbstractThe ultrastructure of the dorsal oesophageal gland ampulla and its relationship with the oesophagus, oesophageal ultrastructure, and control mechanisms in oesophageal activity were studied. Terminal ducts of the sub-ventral glands open through the oesophageal crown at the base of the buccal cavity. The terminal duct of the dorsal oesophageal gland running through the dorsal gutter opens to the exterior at the rim ‘groove’ of the buccal capsule. The posterior oesophageal region is clavate and the cuticle of the lumen folds to form outlet valves, ‘valvulae’. An inconspicuous oesophago-intestinal valve (three lobes) connects oesophagus and intestine and is visualized in the open and shut position. In the female reproductive tract, with the exception of the uterus, the cells lie on a thick, irregular (convoluted) basal lamina. The apical plasma membrane of the uterus, and seminal receptacle, extend into the lumen by microvilli-like projections with which spermatozoa make intimate contact. The lumen of the uterus is filled with oocytes, fertilized and unfertilized. Testicular cells have two parts linked by a rachis. Spermatocytes are elongated with a large nucleus, distinct nuclear membrane, and many granules. The apical membrane of the rachis forms long microvilli-like projections with balloon-like tips. The amoeboid spermatozoa contain membrane specializations, a nucleus devoid of a membrane, and are enclosed by a pseudopodial-like extension.


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.


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