Selective cyclooxygenase 2 inhibitor induces indefinite survival of fully allogeneic cardiac grafts and generates CD4+ regulatory cells

Platelet aggregation and response to aspirin therapy in cardiac allograft vasculopathy

BACKGROUND

Long-term survival after heart transplantation (HTx) is compromised by cardiac allograft vasculopathy (CAV) characterized by coronary macro- and microvascular disease. The pathogenesis of CAV is unclear and may involve coronary thrombosis. We investigated whether HTx patients with CAV had higher platelet aggregation and turnover than HTx patients without CAV and healthy controls. Furthermore, we investigated the anti-platelet effect of low-dose aspirin in HTx patients.

METHODS

We included 57 patients who had undergone HTx (median 8.3 years from HTx) and 57 healthy controls. Platelet aggregation was measured on-aspirin and off-aspirin using impedance aggregometry with adenosine diphosphate (ADP) and arachidonic acid (AA). We evaluated platelet turnover by flow cytometry, CAV burden by coronary angiography and echocardiography, and microvascular function by echocardiographic coronary flow velocity reserve (CFVR).

RESULTS

Off-aspirin, HTx patients with CAV (n = 21) had higher ADP-induced platelet aggregation than healthy controls (p < 0.01) and HTx patients without CAV (n = 36) (p < 0.05). Aspirin treatment reduced AA-induced platelet aggregation in both HTx groups, but HTx patients with CAV had higher platelet aggregation on-aspirin than HTx patients without CAV (p < 0.05). Platelet turnover did not differ between HTx patients with CAV and HTx patients without CAV (p > 0.34). HTx patients with lower CFVR values had higher platelet aggregation than HTx patients with higher CFVR values (p < 0.05).

CONCLUSIONS

Off-aspirin, platelet aggregation was higher in HTx patients with CAV than in HTx patients without CAV and healthy controls. On-aspirin, platelet aggregation was higher in HTx patients with CAV than in HTx patients without CAV. Aspirin monotherapy may not provide sufficient platelet inhibition in HTx patients with CAV.

Inducción de tolerancia por vía oral en trasplante de órganos y tejidos. Revisión de la Literatura

Introducción. La tolerancia oral es la supresión de la respuesta inmune a antígenos administrados con anterioridad por vía oral; su inducción tiene el propósito de evitar el uso de fármacos inmunosupresores, los cuales, dado que son poco específicos a antígenos, vuelven al huésped más susceptible de contraer infecciones y desarrollar neoplasias.Objetivos. Realizar una revisión de la literatura sobre los referentes teóricos más relevantes de la inducción de a tolerancia oral en lo que respecta al trasplante de órganos y tejidos para demostrar que el uso de esta alternativa terapéutica es viable en pacientes trasplantados.Materiales y métodos. Se realizó una revisión de la literatura en PubMed, MEDLINE, LILACS y Embase mediante la siguiente estrategia de búsqueda: periodo de publicación: sin límites; idiomas: Inglés y Español; tipo de artículos: estudios caso-control, revisiones sistemáticas y de la literatura; términos de búsqueda: “T-Lymphocytes, Regulatory”, “Autoimmunity”, Immunosuppression”, “Immune system” and “Immune Tolerance”, y sus equivalentes en español.Resultados. La búsqueda inicial arrojó 719 registros, sin embargo solo 99 abordaban la inducción de la tolerancia oral. Una vez los registros duplicados y los artículos sin acceso a texto completo fueron removidos, se incluyeron 72 estudios en la revisión.Conclusiones. La administración oral de antígenos es una opción efectiva para inducir tolerancia inmunológica en pacientes trasplantados (modelos murinos), pues elimina los efectos adversos que conlleva la terapia inmunosupresora actualmente utilizada.

Induction of Regulatory CD4+ Cells and Prolongation of Fully Major Histocompatibility Complex Mismatched Murine Cardiac Allograft by Shigyakusan

Shigyakusan (also known as Tsumura Japan [TJ]-35) is composed of peony, bitter orange, licorice, and Bupleuri radix is used for cholecystitis and gastritis as an anti-inflammatory agent. We investigated the effect of TJ-35 on alloimmune response in a murine heart transplantation model. CBA mice that underwent transplantation of a C57BL/6 (B6) heart were assigned to four groups: no treatment, TJ-35-exposed, each component-exposed, or each component missing-exposed. The four groups above each received oral administration of TJ-35, each component, or TJ-35 with each component missing from the day of transplantation until 7 days, respectively. Untreated CBA recipients rejected B6 cardiac grafts acutely (median survival time [MST], 7 days). TJ-35-exposed CBA recipients had significantly prolonged B6 allograft survival (MST, 20.5 days). However, MSTs of CBA recipients that had been administered each component and TJ-35 with each component missing did not reach that of TJ-35-exposed recipients. Adoptive transfer of CD4⁺ splenocytes from TJ-35-exposed primary allograft recipients resulted in significant prolonged allograft survival in naïve secondary recipients (MST, 63 days). Flow cytometry studies showed that the percentage of CD4⁺CD25⁺Foxp3⁺ cell population was increased in TJ-35-exposed CBA recipients. In conclusion, TJ-35-induced prolongation of fully allogeneic cardiac allografts and may generate regulatory CD4⁺CD25⁺Foxp3⁺ cells in our model. The effect seemed to require all components of TJ-35.

Treadmill exercise induces murine cardiac allograft survival and generates regulatory T cell

Exercise therapy has been associated with improvement in functional capacity and quality of life. The role of exercise therapy in heart transplant recipients is of great interest for the transplant society, although concerning the effect of exercise therapy, there is little knowledge at present. We analyzed the effects of exercise on alloimmune responses in murine cardiac allograft transplantation. CBA mice (H2^k) underwent transplantation of C57Bl/6 (H2^b) hearts and exercised on a treadmill. Untreated CBA recipients rejected C57Bl/6 cardiac grafts acutely (median survival time [MST], 7 days). CBA recipients treated with treadmill for 1 week after transplantation, and for 1 week both before and after transplantation prolonged allograft survivals (MSTs, 35 and 18 days, respectively). However, treadmill exercise recipients for 1 week before transplantation were not effective to allograft survival (MST, 8 days). Adoptive transfer of whole splenocytes and CD4⁺ cells from treadmill exercise recipients significantly prolonged allograft survival in naive secondary recipients (MSTs, 30 and 52 days, respectively), suggesting that regulatory cells was generated after treadmill exercise. Moreover, flow cytometry studies showed that CD4⁺CD25⁺Foxp3⁺ cell population increased in treadmill exercise recipients. Therefore, postoperative but not pre-operative exercise could induce prolongation of survival of fully allogeneic cardiac allografts and generate CD4⁺CD25⁺Foxp3⁺ regulatory T cells.

Fox smell abrogates the effect of herbal odor to prolong mouse cardiac allograft survival

Background

Herbal medicines have unique odors, and the act of smelling may have modulatory effects on the immune system. We investigated the effect of olfactory exposure to Tokishakuyaku-san (TJ-23), a Japanese herbal medicine, on alloimmune responses in a murine model of cardiac allograft transplantation.

Methods

Naïve or olfactory-dysfunctional CBA mice underwent transplantation of a C57BL/6 heart and were exposed to the odor of TJ-23 until rejection. Some naïve CBA recipients of an allograft were given olfactory exposure to Sairei-to (TJ-114), trimethylthiazoline (TMT), individual components of TJ-23, or a TJ-23 preparation lacking one component. Adoptive transfer studies were performed to determine whether regulatory cells were generated.

Results

Untreated CBA mice rejected their C57BL/6 allografts acutely, as did olfactory-dysfunctional CBA mice exposed to the odor of TJ-23. CBA recipients of a C57BL/6 heart given olfactory exposure to TJ-23 had significantly prolonged allograft survival, whereas those exposed to the odor of TJ-114, TMT, one component of TJ-23, or TJ-23 lacking a component did not. Secondary allograft recipients that were given, at 30 days after transplantation, either whole splenocytes, CD4⁺ cells, or CD4⁺CD25⁺ cells from primary recipients exposed to the odor of TJ-23 had indefinitely prolonged allograft survival.

Conclusions

Prolonged survival of cardiac allografts and generation of regulatory cells was associated with exposure to the odor of TJ-23 in our model. The olfactory area of the brain may have a role in the modulation of immune responses.

An agonistic anti-BTLA mAb (3C10) induced generation of IL-10-dependent regulatory CD4+ T cells and prolongation of murine cardiac allograft

BACKGROUND

The co-inhibitory receptor B and T lymphocyte attenuator (BTLA) has been implicated in the regulation of autoimmunity and may potentially play an important role in allograft tolerance. This study investigated the effect of an agonistic anti-BTLA mAb (3C10) in the fully major histocompatibility complex-mismatched murine cardiac transplantation.

METHODS

CBA mice underwent transplantation of C57BL/6 hearts and received one dose of 3C10 on the day of transplantation (day 0) or four doses of 3C10 on day 0, 3, 6, and 9. Adoptive transfer studies were performed to determine whether regulatory cells were generated. Moreover, to confirm the requirement for regulatory T cell and Th-2 cytokines, anti-interleukin (IL)-2 receptor alpha antibody (PC-61) or anti-IL-10 antibody (JES-2A5) was administered to a 3C10-treated CBA recipient.

RESULTS

CBA mice treated with one and four doses of 3C10 prolonged allograft survival (median survival times [MSTs], 43 and >100 days, respectively). Secondary CBA recipients given whole splenocytes or CD4 cells from primary 3C10-treated CBA recipients had significantly prolonged survival of C57BL/6 hearts (MSTs, >100 in both). Also, flow cytometry studies showed an increased CD4CD25Foxp3 cell population in 3C10-treated mice. Additionally, IL-2 and interferon-γ production were suppressed in 3C10-treated mice, and IL-4 and IL-10 from 3C10-treated CBA mice increased. Moreover, 3C10 directly suppressed alloproliferation in a mixed leukocyte culture. However, administration of PC-61 or JES-2A5 clearly attenuated prolonged survival of 3C10-treated mice (MSTs, 15.5 and 13.5 days, respectively).

CONCLUSION

3C10 could control acute rejection by its suppressive effect on alloreactive T cells and induction of IL-10-dependent regulatory CD4 T cells.

In vitro effects of meloxicam on the number, Foxp3 expression, production of selected cytokines, and apoptosis of bovine CD25+CD4+ and CD25-CD4+ cells

The purpose of this study was to evaluate the effect of meloxicam (MEL) on selected immune parameters of bovine CD25^highCD4+, CD25^lowCD4+, and CD25-CD4+ cells. Peripheral blood mononuclear cells (PBMCs) collected from 12-month-old heifers were treated with MEL at a concentration corresponding to the serum level of this medication following administration at the recommended dose (MEL 5 × 10^-6 M) and at a concentration 10 times lower (MEL 5 × 10^-7 M). After 12 and 24 h of incubation with the drug, the percentage of CD25^highCD4+ cells decreased; however, this disturbance was quickly reversed. Furthermore, the absolute number of CD25^highCD4+ cells in the PBMC populations treated with MEL 5 × 10^-6 M for 48 and 168 h was increased. Prolonged (168 h) exposure to the drug increased the percentage of Foxp3+ cells in the CD25^highCD4+ cell subpopulation. The higher dose of MEL was found to significantly increase the percentage of IFN-γ+ cells among the CD25-CD4+ cells. These results indicated that MEL does not exert an immunosuppressive effect by depleting CD4+ cells and suppression of IFN-γ+ production by these cells. Furthermore, IL-10 and TGF-β production was not changed following exposure to MEL.

Music exposure induced prolongation of cardiac allograft survival and generated regulatory CD4⁺ cells in mice

In clinical practice, music has been used to decrease stress, heart rate, and blood pressure and to provide a distraction from disease symptoms. We investigated sound effects on alloimmune responses in murine heart transplantation. Naïve and eardrum-ruptured CBA/N (CBA, H2(K)) underwent transplantation of a C57BL/6 (B6, H2(b)) heart and were exposed to 1 of 3 types of music-opera (La Traviata), classical (Mozart), and New Age (Enya)-or 1 of 6 different single sound frequencies for 7 days. An adoptive transfer study was performed to determine whether regulatory cells were generated in allograft recipients. Cell-proliferation, cytokine, and flow cytometry assessments were also performed. CBA recipients of a B6 graft exposed to opera and classical music had significantly prolonged allograft survival (median survival times [MSTs], 26.5 and 20 days, respectively), whereas those exposed to 6 single sound frequencies and New Age did not (MSTs, 7, 8, 9, 8, 8, 8, and 11 days, respectively). Untreated and eardrum-ruptured CBA rejected B6 grafts acutely (MSTs, 7 and 8.5 days, respectively). Adoptive transfer of whole splenocytes, CD4(+) cells, and CD4(+)CD25(+) cells from opera-exposed primary recipients resulted in significantly prolonged allograft survival in naive secondary recipients (MSTs, 36, 68, and >50 days, respectively). Cell-proliferation, interleukin (IL)-2 and interferon-γ were suppressed in opera-exposed mice, whereas IL-4 and IL-10 from opera-exposed recipients were up-regulated. Flow cytometry studies showed an increased CD4(+)CD25(+)Foxp3(+) cell population in splenocytes from opera-exposed mice. In conclusion, exposure to some types of music may induce prolonged survival of fully allogeneic cardiac allografts and generate CD4(+)CD25(+)Foxp3(+) regulatory cells.

Inchingorei-san (TJ-117) and Artemisiae Capillaris Herba Induced Prolonged Survival of Fully Mismatched Cardiac Allografts and Generated Regulatory Cells in Mice

We investigated Inchingorei-san (TJ-117), a 6-component Japanese herbal medicine, on alloimmune responses in murine cardiac allograft transplantation. CBA mice underwent transplantation of a C57BL/6 (B6) heart and received oral administration of TJ-117 or each component of TJ-117 from the day of transplantation until 7 days afterward. Naive CBA mice rejected B6 cardiac grafts acutely (median survival time (MST), 7 days). CBA recipients given 1 g/kg/day of TJ-117 had prolonged B6 allograft survival (MST, 37 days). Moreover, given 1 g/kg/day of Artemisiae Capillaris Herba (ACH), one component of TJ-117, indefinitely prolonged B6 allograft survival (MST, >100 days). However, other five components of TJ-117 were less effective than TJ-117 and ACH. Secondary CBA recipients given whole splenocytes, CD4⁺, and CD4⁺CD25⁺ cells from primary ACH-treated CBA recipients with B6 cardiac allografts 30 days after grafting had prolonged survival of B6 hearts (MSTs, 57, >100, and >100 days, resp.). Flow cytometry studies showed that the CD4⁺CD25⁺Foxp3⁺ regulatory cell population was increased in transplant recipients given ACH. Cell proliferation, interleukin-2, and interferon-γ were suppressed in ACH-treated mice, whereas interleukin-4 and interleukin-10 were upregulated. In conclusion, ACH, one component of TJ-117, as well as TJ-117 induced hyporesponsiveness to fully allogeneic cardiac allografts and may generate CD4⁺CD25⁺Foxp3⁺ regulatory cells.

Auditory stimulation of opera music induced prolongation of murine cardiac allograft survival and maintained generation of regulatory CD4+CD25+ cells

BACKGROUND

Interactions between the immune response and brain functions such as olfactory, auditory, and visual sensations are likely. This study investigated the effect of sounds on alloimmune responses in a murine model of cardiac allograft transplantation.

METHODS

Naïve CBA mice (H2k) underwent transplantation of a C57BL/6 (B6, H2b) heart and were exposed to one of three types of music--opera (La Traviata), classical (Mozart), and New Age (Enya)--or one of six different single sound frequencies, for 7 days. Additionally, we prepared two groups of CBA recipients with tympanic membrane perforation exposed to opera for 7 days and CBA recipients exposed to opera for 7 days before transplantation (pre-treatment). An adoptive transfer study was performed to determine whether regulatory cells were generated in allograft recipients. Immunohistochemical, cell-proliferation, cytokine, and flow cytometry assessments were also performed.

RESULTS

CBA recipients of a B6 cardiac graft that were exposed to opera music and Mozart had significantly prolonged allograft survival (median survival times [MSTs], 26.5 and 20 days, respectively), whereas those exposed to a single sound frequency (100, 500, 1000, 5000, 10,000, or 20,000 Hz) or Enya did not (MSTs, 7.5, 8, 9, 8, 7.5, 8.5 and 11 days, respectively). Untreated, CBA mice with tympanic membrane perforations and CBA recipients exposed to opera for 7 days before transplantation (pre-treatment) rejected B6 cardiac grafts acutely (MSTs, 7, 8 and 8 days, respectively). Adoptive transfer of whole splenocytes, CD4+ cells, or CD4+CD25+ cells from opera-exposed primary allograft recipients resulted in significantly prolonged allograft survival in naive secondary recipients (MSTs, 36, 68, and > 100 days, respectively). Proliferation of splenocytes, interleukin (IL)-2 and interferon (IFN)-γ production was suppressed in opera-exposed mice, and production of IL-4 and IL-10 from opera-exposed transplant recipients increased compared to that from splenocytes of untreated recipients. Flow cytometry studies showed an increased CD4+CD25+ Forkhead box P3 (Foxp3)+ cell population in splenocytes from those mice.

CONCLUSION

Our findings indicate that exposure to opera music, such as La traviata, could affect such aspects of the peripheral immune response as generation of regulatory CD4+CD25+ cells and up-regulation of anti-inflammatory cytokines, resulting in prolonged allograft survival.

Danazol induces prolonged survival of fully allogeneic cardiac grafts and maintains the generation of regulatory CD4(+) cells in mice

Danazol, a derivative of testosterone, is useful for treatment of endometriosis as well as pretreatment for in vitro fertilization and embryo transfer, although its mechanisms of action are unclear. The aim of this study was to investigate the effect of danazol on alloimmune responses in murine heart transplantation. CBA male mice (H2(k) ) underwent transplantation of C57BL/6 male (H2(b) ) hearts and received a single dose of danazol (0.4, 1.2 or 4mg/kg/day) by intraperitoneal injection on the day of transplantation and for 6days thereafter. An adoptive transfer study was performed to determine whether regulatory cells were generated. The median survival time (MST) of allografts in danazol-treated (1.2 and 4mg/kg/day) mice was 28 and 63days, respectively, compared with 7days in untreated mice. Moreover, secondary CBA recipients given whole splenocytes or CD4(+) cells from primary danazol-treated (4mg/kg/day) CBA recipients 30days after transplantation had prolonged allograft survival (MSTs, 29 and 60days, respectively). Cell proliferation, interleukin (IL)-2 and interferon-γ were suppressed in danazol-treated mice, whereas IL-4 and IL-10 were up-regulated. Moreover, danazol directly suppressed allo-proliferation in a mixed leukocyte culture. Flow cytometry showed an increased CD4(+) CD25(+) Foxp3(+) cell population in splenocytes from danazol-treated mice. Danazol prolongs cardiac allograft survival and generates regulatory CD4(+) cells.

Aspirin and immune system

The time-tested gradual exploration of aspirin's diverse pharmacological properties has made it the most reliable therapeutic agent worldwide. In addition to its well-argued anti-inflammatory effects, many new and exciting data have emerged regarding the role of aspirin in cells of the immune system and certain immunopathological states. For instance, aspirin induces tolerogenic activity in dendritic cells and determines the fate of naive T cells to regulatory phenotypes, which suggests its immunoregulatory potential in relevance to immune tolerance. It also displays some intriguing traits to modulate the innate and adaptive immune responses. In this article, the immunomodulatory relation of aspirin to different immune cells, such as neutrophils, macrophages, dendritic cells (DCs), natural killer (NK) cells, and the T and B lymphocytes has been highlighted. Moreover, the clinical prospects of aspirin in terms of autoimmunity, allograft rejection and immune tolerance have also been outlined.

Effects of COX-2 inhibitor NS-398 on IL-10 expression in rat fungal keratitis

AIM

To investigate the expression of interleukin-10 (IL-10) and the effect of NS-398(COX-2 inhibitor) on the expression of IL-10 in fungal keratitis in rats, and analyze its effects on anti-fungus immunity.

METHODS

Ninety Wister rats were randomly divided into 3 groups. Group A was blank control group (10 eyes). Group B was fungal keratitis group (40 eyes). Group C was fungal keratitis group treated with NS-398 (40 eyes). PAS staining, 100g/L potassium hydroxide (KOH) smear and fungal culture confirmed the successful establishment of fungal keratitis model. After the central epithelium was scraped, Fusarium solani colonies were applied and contact lens was put on the right cornea of group B and C, and plane contact lens was put on the left cornea of control eyes. Phosphate buffered saline (PBS) eyedrops were given for group B and NS-398 eyedrops for group C. The expression of IL-10 on corneas of group B and C on the 1(st) day, 3(rd) days, 7(th) days, and 14(th) days were detected by immunohistochemistry and semi- quantitative reverse transcription- polymerase chain reaction (RT-PCR).

RESULTS

Histopathologic examination showed neutrophil infiltration and severe tissue necrosis in ulcer cornea. PAS staining confirmed the existence of hyphae and spores in the superficial layer of stroma. In the blank and control groups almost no expression of IL-10 was detected at any observing points. In group B the expression of IL-10 increased at first and decreased thereafter. Its expression also showed significant difference at any observing points (P<0.01). Compared with group B, the expression of IL-10 in group C showed no difference on the 1(st) day, decrease on the 3(rd) day, but a significant increase on the 7(th) day and 14(th) day.

CONCLUSION

IL-10 takes part in the occurrence and development of fungal keratitis. NS-398 can upgrade the expression of IL-10 in fungal keratitis in the later period of the ulcer. Meanwhile, pathologic observation showed a slightly corneal opacity. IL-10 may play an important role in the process of cornea anti-damage repair.

Induction of regulatory T cells and indefinite survival of fully allogeneic cardiac grafts by ursodeoxycholic acid in mice

BACKGROUND

Ursodeoxycholic acid (UDCA) has been used to treat patients with cholestatic and autoimmune liver diseases. Several studies have addressed whether UDCA can inhibit graft rejection in experimental and clinical transplantation, but the results have varied. We investigated the effect of UDCA and the mechanism of its effect on alloimmune responses in a murine model of cardiac transplantation.

METHODS

CBA mice underwent transplantation of a C57BL/10 heart and received a single dose of UDCA. Survival times of the allografts were recorded. An adoptive transfer study was conducted to determine whether regulatory cells were generated. The effects on graft survival of adding FK506 or cyclosporine A (CyA) to UDCA treatment were assessed. Histologic, cell proliferation, and cytokine assessments were performed.

RESULTS

CBA recipients given UDCA (25 mg/kg) had indefinite allograft survival (median survival time [MST], >100 days). UDCA also suppressed proliferation of splenocytes and production of interleukin (IL)-2, IL-6, and interferon-gamma, and up-regulated IL-10 production. Adoptive transfer of either whole splenocytes or CD4+ cells from UDCA-treated allograft recipients resulted in indefinite survival of allografts in naive secondary recipients (MST, >100 days). Adoptive transfer of CD4+ CD25+ cells from UDCA-treated recipients significantly prolonged allograft survival in naive secondary recipients (MST, >80 days). FK506 (0.1 mg/kg/day) was compatible with the induction of indefinite allograft survival by UDCA, whereas CyA (10 mg/kg/day) abrogated the effect of UDCA.

CONCLUSION

UDCA induced unresponsiveness to fully allogeneic cardiac allografts and generated CD4+ CD25+ regulatory cells in our model. FK506, but not CyA, was compatible with UDCA treatment.

The significantly enhanced frequency of functional CD4+CD25+Foxp3+ T regulatory cells in therapeutic dose aspirin-treated mice

CD4(+)CD25(+)Foxp3(+) regulatory T (Treg) cells, produced in the thymus or periphery as a functionally mature T cell subpopulation, play pivotal roles in maintenance of self-tolerance and negative regulation of immune responses. Aspirin (ASA) is widely used to reduce pain, the risk of cardiovascular diseases and allo-graft rejection. However, the effect of ASA on CD4(+)CD25(+)Foxp3(+) Treg cells has yet to be determined. The frequency, phenotype and immunosuppressive function of CD4(+)CD25(+)Foxp3(+) Treg cells were detected in BALB/c mice treated with low or high doses of ASA for 4 weeks. ASA significantly decreased the percentage and number of CD4(+) T cells in the periphery, while ASA remarkably increased the percentage of CD4(+)CD25(+)Foxp3(+) Treg cells in CD4(+)T cells. The total cell numbers of thymocytes were significantly decreased in ASA-treated mice, but the number of CD4(+) CD25(+)Fxop3(+) cells and its ratio in CD4(+)CD8(-) thymocytes were markedly enhanced in the thymi of ASA-treated mice. The phenotype of CD4(+)CD25(+) Treg cells, including the expressions of CD44, CD45RB, CD62L, CD69, GITR and CTLA-4, did not show detectable changes in ASA-treated mice. CD4(+)CD25(+) Treg cells in ASA-treated mice exhibited unimpaired immunosuppressive function on CD4(+)CD25(-) T effector cells. ASA significantly enhanced the frequency of functional CD4(+)CD25(+)Foxp3(+) Treg cells in mice in a therapeutic dose range. The different effects of ASA on CD4(+)CD25(+)Foxp3(+) Treg cells and CD4(+)CD25(-) T cells may potentially make hosts susceptible to tolerance induction which would be beneficial for tolerance induction in patients with autoimmune diseases or allo-grafts. This study may have potential impacts in the clinical application of ASA.

COX-2 inhibition improves immune system homeostasis and decreases liver damage in septic rats

OBJECTIVE

To evaluate cyclooxygenase-2 (COX-2) inhibition by NS-398 in septic rats with respect to immunologic derangements and hepatic damage.

METHODS

Six sham rats (Sham), 24 rats that underwent experimentally induced sepsis using cecal ligation and puncture (CLP), and 24 rats that underwent induced sepsis after treatment with NS-398 (NS-398), were compared. Sham rats were immediately sacrificed. Six each of CLP and NS-398 animals were sacrificed at 3, 6, 12, and 24 h after induction of sepsis. From each rat was obtained liver for COX-2 mRNA copy number determination and blood for quantification of alanine transaminase (ALT), aspartate aminotransferase (AST), interleukin 10 (IL-10), interleukin 6 (IL-6), and tumor necrosis factor alpha (TNFalpha) levels, and CD4:CD8 ratios.

RESULT

Sham rats had a lower COX-2 mRNA copy number than NS-398 rats, which had a lower copy number than CLP rats. CLP and NS-938 rats had IL-10 and IL-6 levels above Sham levels. NS-938 rat IL-10 levels were greater and IL-6 levels less than those of CLP rats. For CLP rats, TNF production sharply declined and then increased above Sham levels; NS-398 rat TNF production was consistently mildly elevated above Sham levels. CD4:CD8 ratios sharply dropped over time; NS-398 showed a more modest decline. CLP rats showed unrelenting climbs in AST and ALT values; NS-398 rat levels peaked at 6 h and returned to normal after 12 h; the biochemical evidence of protection against septic liver damage was also seen morphologically, with ultrastructural and histologic normalization of nuclear appearances 12 h after sepsis induction with NS-398 pretreatment.

CONCLUSION

Septic rats given the COX-2 inhibitor NS-398 showed amelioration of cytokine and cellular immunologic imbalances and decreased liver injury.