Enhanced phagocytic activity of neutrophils caused by administration of egg white derivatives (EWD) in cats injected with cyclophosphamide (CPA)

Lactiplantibacillus plantarum DLPT4 Protects Against Cyclophosphamide-Induced Immunosuppression in Mice by Regulating Immune Response and Intestinal Flora

In this study, the strain Lactiplantibacillus plantarum DLPT4 was investigated for the immunostimulatory activity in cyclophosphamide (CTX)-induced immunosuppressed BALB/c mice. L. plantarum DLPT4 was administered to BALB/c mice by oral gavage for 30 days, and CTX was injected intraperitoneally from the 25th to the 27th days. Intraperitoneal injection of CTX caused damage to the thymic cortex and intestines, and the immune dysfunction of the BALB/c mice. L. plantarum DLPT4 oral administration exerted immunoregulating effects evidenced by increasing serum immunoglobulin (IgA, IgG, and IgM) levels and reducing the genes expression of pro-inflammatory factors (IL-6, IL-1β, and TNF-α) of the CTX-induced immunosuppressed mice. The results of the metagenome-sequencing analysis showed that oral administration of L. plantarum DLPT4 could regulate the intestinal microbial community of the immunosuppressed mice by changing the ratio of Lactiplantibacillus and Bifidobacterium. Meanwhile, the abundance of carbohydrate enzyme (CAZyme), immune diseases metabolic pathways, and AP-1/MAPK signaling pathways were enriched in the mice administrated with L. plantarum DLPT4. In conclusion, oral administration of L. plantarum DLPT4 ameliorated symptoms of CTX-induced immunosuppressed mice by regulating gut microbiota, influencing the abundance of carbohydrate esterase in the intestinal flora, and enhancing immune metabolic activity. L. plantarum DLPT4 could be a potential probiotic to regulate the immune response.

Immune-enhancement effects of tuna cooking drip and its enzymatic hydrolysate in Balb/c mice

Tuna cooking drip (TCD) is a protein rich by-product of canned tuna processing that is typically discarded. In this study, the immune-enhancing activities of TCD and its enzymatic hydrolysate (EH-TCD) were investigated by intraperitoneally administering Balb/c male mice with TCD and EH-TCD for 2 weeks. This administration resulted in an increase in the weight of the spleen and thymus (200-800 mg/kg) and enhanced the proliferation rates of splenocytes (200-800 mg/kg). TCD and EH-TCD significantly increased the production of immunostimulatory cytokines (interleukin-10 and interleukin-2). In addition, TCD and EH-TCD increased serum IgG1 and IgG2a levels in a concentration-dependent manner. Particularly, EH-TCD had a greater immune-enhancing effect than TCD. These results suggest that TCD and EH-TCD exert immune-enhancing effects through an IgG antibody response and T cell activation, and EH-TCD can be used as an immunostimulatory agent.

Oyster (Crassostrea gigas) hydrolysates produced on a plant scale have antitumor activity and immunostimulating effects in BALB/c mice

Oyster extracts have been reported to have many bioactive peptides. But the function of oyster peptides produced by proteolysis is still unknown. In this study, the oligopeptide-enriched hydrolysates from oyster (Crassostrea gigas) were produced using the protease from Bacillus sp. SM98011 at laboratory level, and scaled up to pilot (100 L) and plant (1,000 L) levels with the same conditions. And the antitumor activity and immunostimulating effects of the oyster hydrolysates in BALB/c mice were investigated. The growth of transplantable sarcoma-S180 was obviously inhibited in a dose-dependent manner in BALB/c mice given the oyster hydrolysates. Mice receiving 0.25, 0.5 and 1 mg/g of body weight by oral gavage had 6.8%, 30.6% and 48% less tumor growth, respectively. Concurrently, the weight coefficients of the thymus and the spleen, the activity of natural killer (NK) cells, the spleen proliferation of lymphocytes and the phagocytic rate of macrophages in S180-bearing mice significantly increased after administration of the oyster hydrolysates. These results demonstrated that oyster hydrolysates produced strong immunostimulating effects in mice, which might result in its antitumor activity. The antitumor and immunostimulating effects of oyster hydrolysates prepared in this study reveal its potential for tumor therapy and as a dietary supplement with immunostimulatory activity.

Immunostimulating effects of the polyphenol-rich fraction of sugar cane (Saccharum officinarum L.) extract in chickens

The phagocytic activity of peripheral blood leukocytes (PBL) in chickens orally administered sugar cane extracts (SCE) or polyphenol-rich fraction (PRF) of SCE (500 mg/kg/day) for 3 consecutive days increased significantly, when compared with that of saline-administered control chickens. Chickens orally administered SCE or PRF (500 mg/kg/day) for 3 consecutive days showed significantly higher antibody responses against sheep red blood cells and Brucella abortus than control chickens. In addition, oral administration of SCE or PRF also resulted in a significant increase in the number of IgM- and IgG-plaque forming cell responses of PBL, intestinal leukocytes and splenocytes, when compared with those of control chickens. Furthermore, delayed type hypersensitivity responses to human gamma globulin significantly increased in chickens orally administered SCE or PRF, compared with those of control chickens when evaluated on the basis of net increased wattle thickness at 24, 48 and 72 h after challenge. These results suggest that PRF of SCE has an immunostimulating effect in chickens.

Immunomodulating capacity of commercial fish protein hydrolysate for diet supplementation

Dietary proteins harbour bioactive peptides that can be released by a fermentation process. Fish proteins are a valuable and little-exploited source of potentially active biopeptides. The aim of this research was to evaluate the effects of a commercially available fermented fish protein concentrate (Seacure) (FPC) derived from a fermentation process, on the mucosal immune response in a murine model. BALB/c mice received the FPC or the non-fermented powder at different concentrations (0.20, 0.25 or 0.30mg/ml) for 2, 5 or 7 consecutive days. At the end of each feeding period, histological studies of the gut were carried out and the phagocytic activity of peritoneal macrophages, the number of IgA+ cells in the small intestine lamina propria and bronchial tissue and the number of IL-4+, IL-6+, IL-10+, IFNgamma+ and TNFalpha+ cells in the small intestine lamina propria were determined. Different accumulative doses of FPC did not induce any inflammatory immune response and the normal morphology of the small intestine was not affected. Phagocytic activity of peritoneal macrophages was enhanced following FPC administration at 0.3mg/ml for 7 consecutive days. The number of IgA+ cells increased in the small intestine lamina propria but not in the bronchial tissue. IL-4, IL-6 and IL-10 were all significantly increased in the lamina propria of the small intestine of animals that received FPC. At the same time, some pro-inflammatory cytokines such as IFNgamma and TNFalpha also increased, but the intestinal homoeostasis was maintained and no tissue damage was observed. We conclude that FPC is an immunomodulating food with a demonstrated capacity to enhance non-specific host defense mechanisms.

Egg white derivatives induce tumor necrosis factor-α expression in porcine peripheral blood mononuclear cells

Porcine PBMC derived phagocytic activity in peripheral blood polymorphonuclear cells (PMN) induced by egg white derivatives (EWD) treatment was analyzed at the protein and mRNA level. EWD alone failed to induce phagocytic activity of PMN measured by flow cytometry. But PMN phagocytosis was enhanced by culture supernatant from PBMC treated with EWD, human (h)rTNF-alpha and porcine (p)rIL-1beta, respectively. To identify this phagocytic inducing factor, the culture supernatant was partially purified by gel filtration. Only fraction 8 revealed the enhanced PMN phagocytic activity. This fraction also had a high cross-reactivity with anti-prTNF-alpha polyclonal (p)Ab but not with anti-prIL-1beta pAb, as measured by ELISA, indicating that the culture supernatant from PBMC treated with EWD was independent from IL-1beta. The enhanced PMN phagocytic activity of fraction 8 was also inhibited by anti-prTNF-alpha pAb. Both fraction 8 and hrTNF-alpha produced a single protein band between 16 and 18kDa upon analysis by sodium-dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting using anti-prTNF-alpha pAb, suggesting that the promoter of PMN phagocytosis is TNF-alpha, a 16-18 kDa protein produced by EWD-stimulated PBMC. Porcine TNF-alpha mRNA expression in porcine PBMC analyzed by RT-PCR was also increased by addition of EWD. This study strongly suggests that the immunoenhancing effect of EWD on the phagocytic response of porcine PMN is mediated through TNF-alpha produced by PBMC stimulated with EWD. In addition, the expression of porcine TNF-alpha on PBMC is also increased when stimulated with EWD.

Preventive and therapeutic effects of sugar cane extract on cyclophosphamide-induced immunosuppression in chickens

Effects of oral administration of sugar cane extract (SCE) on immunosuppression in chickens treated with cyclophosphamide (CPA) were evaluated. Three-week-old inbred chickens were inoculated into the crop with SCE (500 mg/kg/day) for three consecutive days before or after injection of CPA 12 or 20 mg/chicken. At the last day of SCE or CPA treatment, all chickens were immunized intravenously with sheep red blood cells (SRBC) and Brucella abortus (BA). Chickens administered SCE showed a significant increase in body weight, gain in body weight/day, relative weight of the bursa of Fabricius and antibody responses to SRBC and BA than untreated control chickens. Chickens injected with CPA alone showed significantly decreased body weight, gain in body weight/day, relative weight of the bursa and antibody responses to SRBC and BA, showing immunosuppression in the bursa-dependent immune system. All chickens administered SCE before or after the treatment with CPA showed significantly higher values in body weight, gain in body weight/day, relative bursal weight and antibody responses to both antigens, when compared to chickens treated with CPA alone. In histological examination, chickens administered SCE showed a typical bursa with well constituted follicles, although chickens treated with CPA alone showed a severely atrophied bursa with rudimentary follicles and enormous proliferation of interfollicular connective tissue. Chickens treated with SCE and CPA showed a well-reconstituted bursa with almost normal structure. These results suggest that SCE has functionally and morphologically reconstituting effects on the bursa-dependent immune system in immunosuppressed chickens induced by injection of CPA.

Immunostimulating and growth-promoting effects of sugar cane extract (SCE) in chickens

Polymorphonuclear cells of the peripheral blood in the chicken significantly increased their phagocytosis when cultured with sugar cane extract (SCE; 250-1,000 microg/ml) for 24 hr. Chickens orally administered SCE (500 mg/kg/day) for 3 or 6 consecutive days at 1 week of age showed significantly higher body weight and gain in body weight/day and a lower food conversion ratio within the growing period of 6 weeks than physiological saline-administered control chickens. Furthermore, oral administration of SCE also resulted in significantly higher immune responses against sheep red blood cells and Brucella abortus. These results suggest that SCE has immunostimulating and growth promoting effects in chickens.

Feline interleukin-8 expression in peripheral blood mononuclear cells induced by egg white derivatives

Feline peripheral blood mononuclear cells (PBMC)-derived chemotactic factor induced by egg white derivatives (EWD) treatment was analyzed at the protein and messenger ribonucleic acid (mRNA) level. EWD itself was not active chemotactic for feline peripheral blood polymorphonuclear cells (PMN). But chemotaxis of PMN was enhanced by either culture supernatant from PBMC treated with EWD or human recombinant (hr) interleukin (IL)-8. Both hr IL-8 and the culture supernatant from PBMC treated with EWD yielded a distinct band, molecular weight of 6-8kDa, in sodium-dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) with 15% loading gel. Therefore, to identify this chemotactic factor, culture supernatant from PBMC treated with EWD was partially purified by anion exchange chromatography on diethylaminoethyl (DEAE)-Sepharose CL-6B and concentrated by ultrafiltration. Only the fraction, which was eluted with 0.3M NaCl, showed a high concentration of total protein and also enhanced the chemotactic activity of PMN. This activity was thereafter designated as eluate. The chemotactic activity of eluate was inhibited by anti-hr IL-8 polyclonal antibody (pAb). A single protein band with 6-8kDa was shown in both the eluate and hr IL-8 when analyzed by SDS-PAGE and Western blotting using anti-hr IL-8 pAb, suggesting that the chemotactic factor for feline PMN is IL-8, 6-8kDa, produced by PBMC treated with EWD. The physicochemical characteristics of eluate were stable in heated (60-100 degrees C), acid (pH 3.0), and alkaline (pH 9.0) conditions. The eluate under these conditions also showed a distinct band in molecular weight of 6-8kDa in SDS-PAGE and Western blotting and was very active in chemotactic activity of PMN.IL-8 mRNA gene expression on feline PBMC was analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) assay using a series of oligonucleotides, each 22 mer, derived from feline IL-8. Feline IL-8 mRNA showed low level in 3-h incubation without EWD, but it was increased in a dose-dependent manner by addition of EWD. Following EWD (10 microg/ml) treatment, IL-8 mRNA expression was rapidly increased up to 6h and decreased by 12h although it was not expressed in freshly prepared PBMC. This study strongly suggested that immunoenhancing effect of EWD on chemotactic response of PMN is mediated by feline IL-8, 6-8kDa, produced by PBMC stimulated with EWD. In addition, the expression of feline IL-8 mRNA on PBMC is increased when stimulated with EWD.