TLR2 and TLR4 molecules and antigen-presenting cell compositions in cecal tonsils of broiler chicks (Gallus gallus domesticus) in the first two weeks of the post-hatch period.

Chickens do not have lymph nodes. Gut-associated lymphoid tissue is the major immunological organization for the digestive system. Cecal tonsils are an important part of this organization. This study is a descriptive and experimental study that was conducted to determine the histological development of the cecal tonsils and the distribution of Toll-like receptor (TLR) 2, TLR4 and antigen-presenting cells during the first 2 weeks of the chick's life. The tissue sections were stained using Crossmon's triple technique, Gordon and Sweet's silver impregnation, and streptavidin-biotin-peroxidase complex methods. The classical tonsil framework with fossa and tonsillar units were observed in 4 days cecal tissue. The web of reticular fibres forming the stroma of the tissue had the impression that the lymphoid cells filling in time. The development of cecal tonsil was completed histologically on the day 10 and following day 14 samples. Regardless of the antigenic stimulation, TLR2, TLR4 and CD83, major histocompatibility complex (MHC) class II molecules are present in proximal cecal tissue. However, CD83-positive dendritic cells in the germinal centre were first distinguished on day 7. Furthermore, the high antigen presentation capacity of the cecum with an intense MHC class II molecule expression was determined. Histological and immunohistochemical findings in this study revealed that both innate and adaptive cecal defence mechanisms were in the learning period during the first 2 weeks. The learning period of innate immunity may require more detailed research. However, the results obtained in this study will be taken into consideration in the vaccination programmes in chicks.

The potential protective role of folic acid against acetaminophen-induced hepatotoxicity and nephrotoxicity in rats.

Folic acid (FA), is a group B vitamin, has high reactive oxygen radicals quenching ability, resulting in protection against oxidative damage in aerobic cell. Acetaminophen (N-acetyl-p-aminophenol, APAP) is a nonsteroidal anti-inflammatory drug, and can promote oxidative damage in liver and kidney tissues. The aim of this study was to investigate whether folic acid has protective effects on oxidative liver and kidney injury caused by experimental APAP toxication. Forty female Sprague dawley rats were divided into 5 groups; control, APAP, FA, APAP+FA, and APAP+N-acetylcysteine (NAC) groups. APAP toxication was induced by oral gavage (3 g/kg bodyweight). FA (20 mg/kg bodyweight) and NAC (150 mg/kg bodyweight) were given by oral gavage to the specified groups. Oxidant and antioxidant parameter were determined in liver and kidney tissues. In addition, the liver and kidney tissues were histological evaluated. When compared with APAP group, superoxide dismutase (SOD) and catalase activities and glutathione levels were statistically higher, malondialdehyde (MDA) level and myeloperoxidase activity (except liver tissue) were statistically lower in both APAP+FA and APAP+NAC. Liver and kidney MDA level and kidney SOD activity were significantly lower in APAP+NAC group compared with APAP+FA group. Co-administration of NAC with APAP was found to provide protection, but hepatic cords were defective in some places and some glomerular tubules also had dilatation. Necrotic areas was reduced in the liver and the glomerular structure was in good condition in the APAP+FA group. As a result, FA might have a protective effect against APAP-induced hepato-nephrotoxicity and oxidative stress in rat.

Investigation of the effects of bisphenol-A exposure on lymphoid system in prenatal stage.

Bisphenol-A (BPA) used in the production of plastic materials is a temperature-soluble agent. It also has a steroid hormone-like activity; therefore, it poses a danger to human health. In our study, we aimed to investigate the effects of BPA on lymph node and spleen in male rats exposed to this agent during prenatal stage. The pregnant female rats were divided into four groups: control, sham, low dose (300 µg/kg BPA), and high dose (900 µg/kg BPA). BPA was dissolved in 1 mL of corn oil and administered to the pregnant rats every day during pregnancy. On the 21st and 45th day after the birth, male rats' lymph node and spleen samples were taken and histopathological examination was performed. Samples were stained with hematoxylin and eosin to determine the general histological appearance, and with CD3 and CD20 immunohistochemically. The results of staining were evaluated by H-score, and statistical analysis was performed. In the samples, BPA applications were not found to cause significant tissue damage. But there was a significant decrease in the immunoreactivities of CD3 and CD20 after BPA applications in both 21st and 45th day samples. After high dose BPA administration, decreased CD3 immunoreactivity was statistically significant. It is thought that BPA does not cause histologically significant tissue damage, but it may impair organ function at cellular level. The investigation of molecules involved in organ function will be useful in revealing the mechanisms that will cause dysfunction.

Protective effect of coenzyme Q10 against bisphenol-A-induced toxicity in the rat testes.

The present study was conducted to investigate the antioxidant, histomorphometric, histochemical, immunohistochemical, biochemical, and cytological effects of coenzyme Q10 (CoQ10) against bisphenol-A (BPA)-induced testicular toxicity in rats. A total of 40 adult male Wistar rats were divided into five equal groups. The control group remained untreated. The vehicle control group was administered corn oil (2 ml/kg/day), the BPA group was given BPA (100 mg/kg/day), the CoQ10 group was supplemented with CoQ10 (10 mg/kg/day), and the rats in the CoQ10-BPA group received CoQ10 (10 mg/kg/day) followed by BPA (100 mg/kg/day) 1 h later. The treatments were administered by oral gavage for 14 days. Results showed that the seminiferous tubule diameters (STDs) and seminiferous epithelium heights (SEHs) at stages VII-VIII and XII-XIV, number of undifferentiated embryonic cell transcription factor-1 (UTF-1) positive cells per tubule, UTF-1 positive tubules (%), plasma glutathione (GSH), and serum superoxide dismutase activities, testicular GSH activity and sperm viability (%) decreased whereas the number of terminal dUTP nick end labeling (TUNEL) positive cells per tubule, TUNEL positive tubules (%), testicular and serum malondialdehyde (MDA) levels, and the rate of mid-piece sperm abnormality increased in the BPA administered group. However, while the STDs at stages VII-VIII and XII-XIV, SEHs at stages VII-VIII, plasma GSH, and serum SOD activities increased, serum MDA level decreased in the CoQ10-BPA group. In conclusion, these results suggest a protective effect of CoQ10 against BPA-induced testicular toxicity in rats.

Histological and immunohistochemical studies of the proximal caecum and caecal tonsils of quail (Coturnix coturnix japonica).

The proximal caecum in quails consists of lymphoid and non-lymphoid structures. The caecal tonsils in the proximal part of the caecum are units of gut-associated lymphoid tissue in poultry. This study aimed to examine the histological characteristics of the proximal caecum, as well as compositions of dendritic cells (DCs) and antigen-presenting cells (APCs) in the caecal tonsil of quails. Tissue sections were stained with Crossman's triple, periodic acid-Schiff, Gordon and Sweet's silver, Congo red and methyl green-pyronin dyes, as well as immunohistochemically by the streptavidin-biotin-peroxidase complex method. Caecal lymphoid tissue was located in the lamina propria and submucosa. Germinative centres were observed within the lymphoid tissue. Reticular fibres were mainly distributed in the border area of the germinal centre with only a few fibres scattered in the centre. Plasma cells were observed in the subepithelial region and germinal centres. Eosinophil granulocytes were prevalent in the lymphoid tissue. Additionally, CD83-immunoreactive DCs and MHC class II immunoreactive APCs were present in the subepithelial area and diffuse lymphoid tissue. While DCs were seen in the germinal centres of tonsillar units, APCs were rarely present in the germinal centres, but they were noticed around the germinal centres. In conclusion, the histological structure of the proximal caecum in quails and the distributions of some immunological cells in the caecal tonsils were revealed. Therefore, the defensive role of the caecal tonsils in the digestive system may be better understood, and comparative studies may be carried out.

Histological investigations on thymus of male rats prenatally exposed to bisphenol A.

Bisphenol A is called as a endocrine-distrupting chemical because of the its steroid-like activity and it used in the construction of plastic containing materials. It is indicated that bisphenol A can pass the human serum, urine, follicular fluid, placenta and umblical cord as a result of the use of substances containing this agent. In this study, we aimed to investigate the effects of bisphenol A on the development of the thymus, a primary lymphoid organ which plays an important role in the specific immunity. The adult pregnant female rats were administered orally with bisphenol A (for 21 days) and postnatal thymus samples were obtained on day 21, 45 and 90 and were performed for histochemical and immunohistochemical staining for CD3, CD4, CD8 and CD79a and TUNEL assay for the apoptotic cells. Evaluation of all groups, CD3, CD4, CD8 and CD79a stainings were decreased in the experimental groups compared with control group. The apoptotic cells were determined in the all groups on day 90 as a result of the thymus involution. It is noted that there was not any histological and morphological damages in the rats prenatally exposed the bisphenol A. The effect of the bisphenol A is unknown in the future, but there is no problem in the adult rats.

MHC class II expression by mast cells in the genital tract of cows.

This work examined the presence of MHC class II molecules expressing mast cells in oviduct, uterus and vaginal tissues in cows. The tissue samples of five cows were collected from a local slaughterhouse. Toluidine blue pH 0.5 (TB) and avidin-biotin peroxidase complex (ABC) staining procedures applied to adjacent sections from tissue samples. It was determined that some TB + cells were also gave positive reaction with strept ABC staining for MHC II molecules. To our knowledge this is the first evidence indicating the presence of MHC class II molecules expressing mast cells in the cow.