• Parasites, Hosts and Diseases
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• v.27 no.2
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• pp.79-86
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• 1989

A pathogenic free-living amoeba, Naegleria fowleri, causes primary amoebic meningoencephalitis to human and experimental animals. This infection is rare, but the mortality is very high. Nowadays, drug treatment or active immunization of human or mice are being tried with partial effectiveness. This study shows passive immunization effect by transfer of immunized spleen cells, serum, or milk from immunized mother in mouse experimental model. Young BALB/c mice were immunized intraperitoneally with $2~3{\times}10^{6}$ trophozoites of N. fowleri, and spleen cells and sera were collected for injection to recipient mice. There were seven transfer groups, i.e., immunized mouse serum, spleen cells, serum and spleen cells, normal mouse serum, spleen cells, serum and spleen cells, and control group. Three days later, BALB/c mice were inoculated with $1{\times}10^{4}$ trophozoites of N. fowleri intranasally. After infection, decreased mortality ana prolonged survival time of mice were noted in immunized Bloops compared with non.immuniBed control group. The groups Injected with immunized spleen cells or normal serum shewed lower moltality than that of controls bult showed no changes of Serum IgG level. The groups injected with immunized serum or normal spleen cells showed increased serum IgG level after immunization but hundred percent mortality was observed. Mother mice were ifnfnunised increperitqneeliy with $2~3{\times}10^{6}$ trephozoites of N. fowleri at the end of pregnancy and weaning Period. Soon after the delivery, Jitters born of non-immunszed mother were matched with immunized mother for feeding immune milk. After three weeks, the litters were infected with $1{\times}10^{4}$ trophozeites of N. fowleri or sacrificed for serum collection to measure the IgG levels. The results show that anti-JV. fowleri IgG from mother was transferred to litter through milk but this IgG did not inauence the mortality or survival time of the infected mice.

• Journal of Microbiology and Biotechnology
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• v.21 no.4
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• pp.405-411
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• 2011

Avian influenza virus vaccines produced in oil-emulsified inactivated form with antigen content of at least 160 hemagglutinin units (HAU) induced immunity in birds. However, in addition to enhancing the effect of the adjuvant(s), other additional supplemented biological compounds included in inactivated vaccines could produce higher levels of antibody. We examined in chickens, Vietnamese ducks, and muscovy ducks the adjuvant effect of Sophy ${\beta}$-glucan (SBG), a ${\beta}$-1,3-1,6 glucan produced by the black yeast Aureobasidium pollulans strain AF0-202, when administered with an avian influenza H5 subtype vaccine. In Experiment 1, 40 chickens (ISA Brown hybrid), allocated to four groups of ten each, were immunized with Oil-H5N1(VN), Oil-H5N1(CN), Oil-H5N2(CN), and saline (control group), respectively. In Experiment 2, chickens (ISA Brown hybrid), muscovy ducks (French hybrid), and Vietnamese ducks (indigenous Vietnamese) were used to further assess the effect of SBG on immunogenicity of the Oil-H5N1(VN) Vietnamese vaccine. ELISA and hemagglutination inhibition (HI) assays were used to assess the antibody response. The H5 subtype vaccines initiated significantly higher immune responses in the animals dosed with SBG, with 1.0-1.5 $log_2$ higher HI titers and 10-20% ELISA seroconversion, compared with those not dosed with ${\beta}$-glucan. Notably, some of the animals dosed with SBG induced HI titers higher than 9.0 $log_2$ following boosting immunization. Taken together, our serial studies indicated that SBG is a potential effector, such as enhancing the immune response to the H5 vaccines tested.

• Journal of Microbiology and Biotechnology
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• v.30 no.6
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• pp.811-821
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• 2020

Mycobacterium tuberculosis produces mycolic acids which are relevant for persistence, recalcitrance to antibiotics and defiance to host immunity. c-di-GMP is a second messenger involved in transition from planktonic cells to biofilms, whose levels are controlled by diguanylate cyclases (DGC) and phosphodiesterases (PDE). The transcriptional regulator dosR, is involved in response to low oxygen, a condition likely happening to a subset of cells within biofilms. Here, we found that in M. bovis BCG, expression of both BCG1416c and BCG1419c genes, which code for a DGC and a PDE, respectively, decreased in both stationary phase and during biofilm production. The kasA, kasB, and fas genes, which are involved in mycolic acid biosynthesis, were induced in biofilm cultures, as was dosR, therefore suggesting an inverse correlation in their expression compared with that of genes involved in c-di-GMP metabolism. The relative abundance within trehalose dimycolate (TDM) of α-mycolates decreased during biofilm maturation, with methoxy mycolates increasing over time, and keto species remaining practically stable. Moreover, addition of synthetic c-di-GMP to mid-log phase BCG cultures reduced methoxy mycolates, increased keto species and practically did not affect α-mycolates, showing a differential effect of c-di-GMP on keto- and methoxy-mycolic acid metabolism.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.3 no.1
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• pp.99-128
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• 1997

In order to investigate the effects of Kyegyoksan on antitumor effects after Sarcoma 180 cells transplantation into the peritoneal cavity or left groin in mice, and immune depression in mice induced by methotrexate, the extracts of its herbal medicines were orally administered for 14 or 21 days. Experimental studies were performed for measureance of $IC_{50}$ in MTT assay, mean survival days, tumor and body weights for antitumor effects, delayed type hypersensitivity, hemagglutinine titer, hemolysin titer, rosette forming cells, interleukin-2 productivity, lymphocyte transformation, natural killer cell activity and phagocytic activity for immune responses in the immune depressed ICR mice, and SGOT, SGPT, BUN and creatinine for liver and kidney protective function in SO-rats. The results were obtained as follows: 1. From the results of MTT assay, the Kyegyoksan exstracts for SUN-1 and SUN-C4 were inhibited cell viability. 2. Mean survival time in Kyegyoksan-treated group was slightly increased with no effectiveness, as compared with the control group. 3. Tumor weight in Kyegyoksan-treated group was depressed with the statistical significance, as compared with the control group(p<0.01). 4. Body weight in Kyegyoksan-treated group was incresed with the statistical significance, as compared with the control group(p<0.05). 5. Delayed type hypersensitivity in Kyegyoksan-treated group was slightly incresed with no effctiveness, as compared with the control group. 6. Hemagglutinin titer in Kyegyoksan-treated group was incresed with the statistical significance(p<0.05), but hemolysin titer was slightly incresed with no effectiveness, as compared with the control group. 7. Rosette forming cells in Kyegyoksan-treated group was incresed with the statistical significance, as compared with the control group(p<0.001). 8. Interleukin-2 productivity in Kyegyoksan-treated group was incresed with the statistical significance, as compared with the control group(p<0.001). 9. Lymphocyte transfomation in Kyegyoksan-treated group was incresed with the statistical significance, as compared with the control group(p<0.01). 10. Natural killer cell activity in Kyegyoksan-treated group at E/T ratio 100 : 1 was incresed with the statistical significance(p<0.01), but at E/T ratio 50 : 1 and 10 : 1 was slightly incresed with no effectiveness, as compared with the control group. 11. Phagocytic activity in Kyegyoksan-treated group was slightly incresed with no effectiveness, as compared with the control group. 12. The levels of serum glutamic oxalacetic transaminase, serum glutamic pyruvic transaminase, blood urea nitrogen and serum creatinine in Kyegyoksan-treated group were not effective change, as compared with the control group. According to the above results, it could be suggested that Kyegyoksan have prominent antitumor effects, enhance both cellular and humoral immunity, and have no injury to liver and kidney functions.

• Clinical and Experimental Pediatrics
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• v.48 no.5
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• pp.506-511
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• 2005

Purpose : Streptococcus pneumoniae serotype 6B and 6A are important pathogens in pneumococcal infections. It is commonly assumed that the 6B vaccines elicit antibodies cross-reacting with the 6A serotype and the cross-reactive antibodies protect against infections of 6A. To examine this assumption, we measured the opsonophagocytic capacity to serotype 6A and 6B in adults. Methods : Twenty-four adults were immunized with pneumococcal PS vaccine that contains 6B PS. Their preimmune and postimmune sera were studied for the capacity to opsonize 6B and 6A serotypes with opsonophagocytic killing assay. Results : Opsonization titers to 6B were significantly higher than those to 6A in preimmune and postimmune sera. Because significant increasesof opsonization titers were observed in adults with polysaccharide vaccines for 6A(cross-reactive) serotype as well as for 6B(vaccine) serotype, 6B PS in vaccine elicited cross-protective antibodies to 6A, but not in all cases. One adult did not have detectable levels of opsonization titers to 6A after immunization. Conclusion : Although 6B PS in pneumococcal PS vaccine elicits antibodies cross-reacting with 6A serotype in some adults, it may not occur always. This study should be extended to other age groups such as children and elderly people. The presence of the cross-protection should be directly determined in clinical trials of the pneumococcal vaccines as well as during the postlicensure monitoring surveys by serotyping the clinical isolates of pneumococci.

• Journal of Nutrition and Health
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• v.37 no.6
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• pp.431-439
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• 2004

Scutellariae Radix (Scu.), one of the immune-regulatory substances, is recognized to play the role in the metabolic process of inflammation, allergy and immunity. It has been traditionally used in the Oriental medicine to treat inflammatory bowel diseases (IBD). The purpose of this study was to evaluate the effects of water extracts of Scutellariae Radix on the spleen lymphocyte immune function in the Balb/c female mice treated with dextran sodium sulfate (DSS) to induce colitis. Water extract of Scutellariae Radix (100 mg/kg) and sulfasalazine (50 mg/kg) were administrated orally for 2 weeks of experimental period. Mice were divided into three experimental groups randomly: DSS group (5％ DSS was ad libitum for 5 days) as control group, DSS ＋ Scu. (water extracts of Scutellariae Radix for 2 weeks after 5％ DSS was ad libitum for 5 days) as experimental group, and DSS ＋ Sulfasalazine group (Sulfasalazine for 2 weeks after 5％ DSS was ad libitum for 5 days) as positive control group. Levels of Ig A, Ig E, CD4$^{＋}$, CD8$^{＋}$, TNF-$\alpha$ and other cytokines were measured. Treatment of DSS for 5 days induced bowel inflammation and the treatment with Scu. water exteract and sulfasalazine significantly recovered the damage. The length of intestine of DSS group was significantly shorter than that of other groups. The serum and fecal concentration of Ig A of SS ＋ Scu group was higher than those of DSS group. The contents of CD4$^{＋}$ T cells was higher in the DSS ＋ Scu. group than the other groups and CD8$^{＋}$ T cells was the lowest in DSS ＋ Sulfasalazine group. The Ig A level of cultured supernatant of spleen lymphocyte was the highest, while the Ig E level was the lowest in SS ＋ Scu group. The concentration of TNF-$\alpha$, cytokine secreted from the Th1 cell in the supernatant spleen lymphocyte, was the highest in the DSS group and the lowest in the DSS ＋ Scu. group. The concentration of IFN-${\gamma}$ and ll...-12 was lower in the DSS ＋ Scu. group than those of the other groups. The concentration of IL-4 in the supernatant of spleen lymphocyte was the lowest in the DSS ＋ Scu. group but IL-10 was not significantly different. Based on these findings, water extract of Scutellariae Radix exhibited the inhibitory effect via IL-4 production thereby inhibited the production of Ig E and strengthened immune system, and alleviated injury in DSS- induced colitis mice model.

• Environmental Mutagens and Carcinogens
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• v.22 no.2
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• pp.112-124
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• 2002

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been reported to exert detrimental toxicities on various organ systems including reproductive, cardiovascular, nervous, or dermal system. Immunomodulatory effects of TCDD is thymic atrophy, downregulation of cytotoxic T or B lymphocyte differentiation and activation, which were demonstrated using experimental animals, whereas immunotoxicity in human has not been investigated well. This study was proceeded to evaluate general immunologic spectrum of the Korean Vietnam War veterans exposed to TCDD during their operation, and compare with that of the non-exposed control subjects with similar age. Regarding composition and quantity, immune cells in peripheral blood collected from the TCDD-exposed was not much different from those of the control except decreased red blood cell, hemoglobin and hematocrit level. Furthermore, plasma IgG2, G3, and G4 isotype distribution was similar between two groups, but IgG1 level was significantly lowered in the TCDD-exposed, indicating a TCDD-mediated functional alteration of B cells. Significantly enhanced level of IgE in plasma, a hallmark of dermal or respiratory allergic response, was also observed in the TCDD-exposed compared with that of the control. Elevated generation of IL-4 and IL-10 was resulted from in vitro stimulation of T cells with PMA plus ionomycin or PHA, respectively, from the TCDD-exposed in comparison to those of the control, suggesting a skewed type-2 response. In addition, the level of IFN${\gamma}$, a multifunctional cytokine for T cell-mediated immunity, was lowered in the TCDD-exposed with upregulation of tumor necrosis factor $\alpha$. The present study suggests that TCDD exposure disturbs immunohomeostasis in humans observed as an aberrant plasma IgE and IgG1 levels and dysregulation of T cell activities.

• Parasites, Hosts and Diseases
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• v.56 no.4
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• pp.325-334
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• 2018

Toxoplasma gondii is an apicomplexan zoonotic protozoan parasite that infects most species of warm-blooded animals, including humans. The heavy incidence and severe or lethal damage caused by T. gondii infection clearly indicate a need for the development of an effective vaccine. T. gondii GRA8 is a member of the dense granules protein family and is used as a marker of acute infection. In the present study, we evaluated the protective immunity induced by DNA vaccination based on a recombinant eukaryotic plasmid, pDsRed2-GRA8, against acute toxoplasmosis in mice. BALB/c mice were intramuscularly immunized with the pDsRed2-GRA8 plasmid and then challenged by infection with the highly virulent GFP-RH strain of T. gondii. The specific immune responses and protective efficacy against T. gondii of this vaccine were analyzed by measuring cytokine and serum antibody titers, splenocyte proliferation assays, and the survival times of mice after challenge. Our results showed that mice immunized with pDsRed2-GRA8 demonstrated specific humoral and cellular responses, induced higher IgG antibody titers with predominant IgG2a production; increased levels of IL-10, IL-12 (p70), $IFN-{\gamma}$, $TNF-{\alpha}$, and splenocyte proliferation; and prolonged survival times compared to those of control mice. The present study showed that DNA immunization with pDsRed2-GRA8 induced humoral and cellular immune responses, and all immunized mice showed greater Th1-type immune responses and longer survival times than those of control mice. These results indicated that T. gondii GRA8 DNA immunization induces a partial protective effect against acute toxoplasmosis.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.4031-4036
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• 2012

Background: The negative signaling provided by interactions of the co-inhibitory molecule, programmed death-1 (PD-1), and its ligands, B7-H1 (PD-L1) and B7-DC (PD-L2), is a critical mechanism contributing to tumor evasion; blockade of this pathway has been proven to enhance cytotoxic activity and mediate antitumor therapy. Here we evaluated the anti-tumor efficacy of AAV-mediated delivery of the extracellular domain of murine PD-1 (sPD-1) to a tumor site. Material and Methods: An rAAV vector was constructed in which the expression of sPD-1, a known negative regulator of TCR signals, is driven by human cytomegalovirus immediate early promoter (CMV-P), using a triple plasmid transfection system. Tumor-bearing mice were then treated with the AAV/sPD1 construct and expression of sPD-1 in tumor tissues was determined by semi quantitative RT-PCR, and tumor weights and cytotoxic activity of splenocytes were measured. Results: Analysis of tumor homogenates revealed sPD-1 mRNA to be significantly overexpressed in rAAV/sPD-1 treated mice as compared with control levels. Its use for local gene therapy at the inoculation site of H22 hepatoma cells could inhibit tumor growth, also enhancing lysis of tumor cells by lymphocytes stimulated specifically with an antigen. In addition, PD-1 was also found expressed on the surfaces of activated CD8+ T cells. Conclusion: This study confirmed that expression of the soluble extracellular domain of PD-1 molecule could reduce tumor microenvironment inhibitory effects on T cells and enhance cytotoxicity. This suggests that it might be a potential target for development of therapies to augment T-cell responses in patients with malignancies.

• Parasites, Hosts and Diseases
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• v.49 no.2
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• pp.115-123
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• 2011

Toxoplasma gondii Korean isolate (KI-1) tachyzoites were inoculated intraduodenally to BALB/c mice using a silicon tube, and the course of infection and immune responses of mice were studied. Whereas control mice, that were infected intraperitoneally, died within day 7 post-infection (PI), the intraduodenally infected mice survived until day 9 PI (infection with $1{\times}10^5$ tachyzoites) or day 11 PI (with $1{\times}10^6$ tachyzoites). Based on histopathologic (Giemsa stain) and PCR (B1 gene) studies, it was suggested that tachyzoites, after entering the small intestine, invaded into endothelial cells, divided there, and propagated to other organs. PCR appeared to be more sensitive than histopathology to detect infected organs and tissues. The organisms spread over multiple organs by day 6 PI. However, proliferative responses of splenocytes and mesenteric lymph node (MLN) cells in response to con A or Toxoplasma lysate antigen decreased significantly, suggesting immunosuppression. Splenic $CD4^+$ and $CD8^+$ T-Iymphocytes showed decreases in number until day 9 PI, whereas IFN-${\gamma}$ and IL-10 decreased slightly at day 6 PI and returned to normal levels by day 9 PI. No TNF-${\alpha}$ was detected throughout the experimental period. The results showed that intraduodenal infection with KI-1 tachyzoites was successful but did not elicit significant mucosal immunity in mice and allowed dissemination of T. gondii organisms to systemic organs. The immunosuppression of mice included reduced lymphoproliferative responses to splenocytes and MLN cells to mitogen and low production of cytokines, such as IFN-${\gamma}$, TNF-${\alpha}$, and IL-10, in response to T. gondii infection.