P40 Levels Research Articles

Local Host Response to Chlamydial Urethral Infection in Male Guinea Pigs

Very little is known about the host response to chlamydial genital infection in the male, particularly about the nature of the local response in the urethra. In this study, the pathological and immunologic responses to urethral infection of the male guinea pig with Chlamydia caviae (Chlamydophila caviae) were characterized both during a primary infection and following a challenge infection. A dose-response experiment found that the 50% infectious dose for male urethral infection was 78 inclusion-forming units. The histopathologic response was similar to that of the female, with an initial acute inflammatory response followed by a chronic inflammatory response and plasma cell infiltration. Production of IgG and IgA antibodies in local urethral secretions developed following infection, and levels of both increased in a typical anamnestic response following a challenge infection. CD4 and CD8 T cells, as well as B cells, were observed in the local site by flow cytometry, with a slightly increased number of CD8 cells. Following challenge infection, the dominant anamnestic response was solely in the B-cell compartment, with only a minimal number of T cells. The T-cell response was clearly a Th1 response, as judged by increased levels of gamma interferon (IFN-gamma), interleukin-12 p40 (IL-12p40), and IL-2. The proinflammatory cytokines and chemokines IL-8, IL-1beta, tumor necrosis factor alpha (TNF-alpha), CCL2 (monocyte chemoattractant protein 1 [MCP-1]), and CCL5 (RANTES) were elicited in the urethra following primary infection, but only CCL5 showed increased levels upon challenge. This study represents the first comprehensive analysis of the local immune response in the male urethra to a chlamydial genital infection.

CD40 ligand-triggered human dendritic cells mount interleukin-23 responses that are further enhanced by danger signals

Interleukin (IL)-23 is a heterodimeric cytokine composed of the IL-23-specific subunit p19 and the p40 subunit which also constitutes part of IL-12. IL-23 propagates development of Th17 cells, a novel T cell subset which produces IL-17 but no interferon-γ or IL-4. For both, IL-23 and IL-23-driven IL-17, a crucial role in autoimmune diseases such as experimental autoimmune encephalomyelitis, collagen-induced arthritis, and colitis is well accepted. Recent studies indicate that there is also a role for IL-23 and IL-17 in tumorigenesis, promoting tumor growth and vascularization, and affecting tumor incidence. We show that human CD14+ peripheral blood monocyte-derived dendritic cells (DC), as used for clinical applications in anti-tumor immunization strategies, produce high amounts of IL-23. CD40-triggering of immature and mature DC but not of primary monocytes induced a rapid expression of high levels of IL-23, free p40, and minor levels of IL-12. Upon stimulation of DC subsets with a variety of different danger signals such as single stranded and double stranded RNA, bacterial components or viral infections, IL-23 expression pattern was analyzed. Interestingly, co-stimulation with CD40L enabled IL-23 expression by DC subsets towards danger signals to which they have been unresponsive upon single stimulation. Furthermore, we detected two novel splice variants of the IL-23-specific subunit p19 that could be associated with the regulation of IL-23 expression. Data presented here might have an impact on DC-based cancer vaccination strategies and contribute to a better understanding of the complex regulation of the heterodimeric cytokine IL-23.

The Elevated Interferon Gamma Production is an Important Immunological Marker in HAM/TSP Pathogenesis

Human T-lymphotropic virus type 1 (HTLV-1) is the agent of the HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), which may occur in >5% of patients during their lifetime. HTLV-1-infection causes disturbances in the immune system, and the viral load may also play an important role in the pathogenesis of HAM/TSP. Some cytokines are involved in the pathogenesis of this disorder. We have determined IL-2, IL-4, IL-10, IL-12 p70, IFN-gamma and TNF-alpha production among HTLV-1-infected subjects from our HTLV-out Clinic in Institute of Infectious 'Emílio Ribas' in Sao Paulo city, Brazil. PBMC obtained from healthy controls (n = 32), asymptomatic HTLV-1 carriers (n = 68) and HAM/TSP patients (n = 44) were grown in the absence and in the presence of phytohaemagglutinin (PHA), and the supernatants' fluids were measured for cytokines production. IL-2 levels were increased in the asymptomatic HTLV-1 carriers, and IFN-gamma was increased in both groups of patients (asymptomatic HTLV-1 carriers and more significantly among HAM/TSP patients). IL-4, IL-10, TNF-alpha and IL-12 p70 levels were not significantly increased on both groups of patients, as compared with controls. The major finding of this study is that IFN-gamma was an important cytokine for the HAM/TSP pathogenesis. Therefore, immune modulation of IFN-gamma may be critical to treat of HAM/TSP patients.

Lactobacillus delbrueckii UFV-H2b20 induces type 1 cytokine production by mouse cells in vitro and in vivo

Lactobacillus delbrueckii UFV-H2b20 has been shown to increase clearance of bacteria injected into the blood of germ-free mice. Moreover, it induces the production of type 1 cytokines by human peripheral mononuclear cells. The objective of the present study was to investigate the production of inflammatory cytokines [interleukin-12 (IL-12 p40), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma)] triggered in vitro by live, heat-killed or lysozyme-treated L. delbrueckii UFV-H2b20 and in vivo by a live preparation. Germ-free, L. delbrueckii-monoassociated and lipopolysaccharide (LPS)-resistant C3H/HeJ mice were used as experimental models. UFV-H2b20 induced the production of IL-12 p40 and TNF-alpha by peritoneal cells and IFN-gamma by spleen cells from germ-free or monoassociated Swiss/NIH mice and LPS-hyporesponsive mice (around 40 ng/mL for IL-12 p40, 200 pg/mL for TNF-alpha and 10 ng/mL for IFN-gamma). Heat treatment of L. delbrueckii did not affect the production of these cytokines. Lysozyme treatment decreased IL-12 p40 production by peritoneal cells from C3H/HeJ mice, but did not affect TNF-alpha production by these cells or IFN-gamma production by spleen cells from the same mouse strain. TNF-alpha production by peritoneal cells from Swiss/NIH L. delbrueckii-monoassociated mice was inhibited by lysozyme treatment. When testing IL-12 p40 and IFN-gamma levels in sera from germ-free or monoassociated Swiss/NIH mice systemically challenged with Escherichia coli we observed that IL-12 p40 was produced at marginally higher levels by monoassociated mice than by germ-free mice (40 vs 60 ng/mL), but IFN-gamma was produced earlier and at higher levels by monoassociated mice (monoassociated 4 and 14 ng/mL 4 and 8 h after infection, germfree 0 and 7.5 ng/mL at the same times). These results show that L. delbrueckii UFV-H2b20 stimulates the production of type 1 cytokines in vitro and in vivo, therefore suggesting that L. delbrueckii might have adjuvant properties in infection in which these cytokines play a major role.

Unmasking of a protective tumor necrosis factor receptor I–mediated signal in the collagen‐induced arthritis model

To examine the relative importance of tumor necrosis factor receptor I (TNFRI) signaling in the hematopoietic tissue compartment in the progression of collagen-induced arthritis (CIA), a model of rheumatoid arthritis (RA). DBA/1 mice were administered a lethal radiation dose and were then rescued with bone marrow derived from either DBA/1 or TNFRI(-/-) mice. CIA was then induced, and disease progression was characterized. Surprisingly, mice with CIA that received TNFRI(-/-) donor marrow developed increased disease severity as compared with control mice with CIA. This could not be attributed to an increased primary response to collagen or to the contribution of a non-DBA genetic background. In mice that received TNFRI(-/-) bone marrow, histologic markers of advanced disease were evident shortly after initiation of the immune response to collagen and long before clinical evidence of disease. Serum TNFalpha was undetectable, whereas serum interleukin-12 p40 levels were increased, at the end point of the study in mice that received TNFRI(-/-) bone marrow. These data raise the intriguing possibility of the existence of an antiinflammatory, TNFRI-mediated circuit in the hematopoietic compartment. This circuit bears a resemblance to the switch in TNFalpha function that has been observed during the resolution of bacterial infections. These data suggest that TNFRI-mediated signals in the radioresistant tissues contribute to disease progression, whereas TNFRI-mediated signals in the radiosensitive tissues can contribute to protection from disease. We thus put forward the hypothesis that the degree of response to TNFalpha blockade in RA is dependent in part on the relative genetic strengths of these 2 pathways.

Xanthine oxidase inhibitor allopurinol attenuates the development of diabetic cardiomyopathy

In this study, we investigated the effect of the xanthine oxidase (XO) inhibitor, allopurinol (ALP), on cardiac dysfunction, oxidative-nitrosative stress, apoptosis, poly(ADP-ribose) polymerase (PARP) activity and fibrosis associated with diabetic cardiomyopathy in mice. Diabetes was induced in C57/BL6 mice by injection of streptozotocin. Control and diabetic animals were treated with ALP or placebo. Left ventricular systolic and diastolic functions were measured by pressure-volume system 10 weeks after established diabetes. Myocardial XO, p22(phox), p40(phox), p47(phox), gp91(phox), iNOS, eNOS mRNA and/or protein levels, ROS and nitrotyrosine (NT) formation, caspase3/7 and PARP activity, chromatin fragmentation and various markers of fibrosis (collagen-1, TGF-beta, CTGF, fibronectin) were measured using molecular biology and biochemistry methods or immunohistochemistry. Diabetes was characterized by increased myocardial, liver and serum XO activity (but not expression), increased myocardial ROS generation, p22(phox), p40(phox), p47(phox), p91(phox) mRNA expression, iNOS (but not eNOS) expression, NT generation, caspase 3/7 and PARP activity/expression, chromatin fragmentation and fibrosis (enhanced accumulation of collagen, TGF-beta, CTGF and fibronectin), and declined systolic and diastolic myocardial performance. ALP attenuated the diabetes-induced increased myocardial, liver and serum XO activity, myocardial ROS, NT generation, iNOS expression, apoptosis, PARP activity and fibrosis, which were accompanied by improved systolic (measured by the evaluation of both load-dependent and independent indices of myocardial contractility) and diastolic performance of the hearts of treated diabetic animals. Thus, XO inhibition with ALP improves type 1 diabetes-induced cardiac dysfunction by decreasing oxidative/nitrosative stress and fibrosis, which may have important clinical implications for the treatment and prevention of diabetic cardiomyopathy and vascular dysfunction.

Serum and synovial fluid levels of p40 IL12/23 in spondyloarthropathy patients

IL-23 is the main inductor in Th17 polarization of naive T cells, inducing IL-17 production. IL-17 has been demonstrated to be elevated in ankylosing spondylitis (AS). The p40 subunit is common to IL-12 and IL-23. We assessed serum and synovial levels of p40 IL12/23 in spondyloarthropathy (SpA) patients and the evolution under anti-TNF. SpA patients fulfilling ESSG criteria were included. Healthy volunteers served as controls. P40 IL12/23 was assessed using Human Quantikine ELISA (R&D Systems), and at the same time, BASDAI, ESR, CRP, IL-17, MMP-3. Patients treated with anti-TNF were evaluated again after 10 weeks of treatment. Statistical analysis used Mann Whitney and correlation tests. Twenty-seven SpA outpatients (20 men), mean age 40.3 years, mean disease duration 10.5 years, HLA B27 positive n = 21, peripheral arthritis n = 8, mean BASDAI 45.7, mean CRP 30.7 mg/l, and 24 controls (12 men), mean age 50.4 years, were included. There is no statistical difference in serum levels of p40IL12/23 between patients (mean 77.8 pg/ml) and controls (103 pg/ml) and between patients with axial and peripheral involvement. Levels were higher in HLA B-27 negative patients (p = 0.02). No statistical correlation was found between p40 IL12/40 serum levels and each of BASDAI, ESR, CRP, serum levels of IL 17, MMP 3. Fourteen AS patients were treated with TNF blockers. Whereas significant reduction in BASDAI, ESR, and CRP were obvious after treatment, there was no significant change in serum level of p40 IL12/23. Mean levels of synovial p40 IL12/23 were higher in SpA patients (n = 6; mean 536 pg/ml) compared to osteoarthritis patients (n = 3; 133 pg/ml) and compared with paired serum SpA levels. These results suggest that serum levels of p40 IL-12/23 may not be considered as a biologic tool of disease activity assessment in SpA patients.

Minocycline for the treatment of sarcoidosis: is the mechanism of action immunomodulating or antimicrobial effect?

A 47-year-old female was diagnosed to have pulmonary, ocular, and nodular-type muscular sarcoidosis. Seven years later, nodules developed in all limb muscles. She received minocycline 200 mg daily, which resulted in an obvious reduction of the muscular sarcoidosis with a significant decrease in the serum angiotensin-converting enzyme level. Nine months later, the minocycline was discontinued, thus resulting in a rapid recurrence of the disease. The immediate readministration of minocycline again resulted in a prompt improvement. We detected Propionibacterium acnes within the granulomas in the affected muscle by an immunohistochemistry. More interestingly, we found a decrease in the circulating levels of interleukin-12 p40 and interferon-inducible protein-10 during the minocycline therapy. The minocycline therapy may be effective for sarcoidosis and the fact that the disease rapidly relapsed after discontinuation of the minocycline administration suggests that the mechanism of action in this case may be immunomodulating but not antimicrobial effect.

The 3′UTR 1188 A/C polymorphism in the interleukin- 12p40 gene ( IL-12B) is associated with lepromatous leprosy in the west of Mexico

Leprosy is a chronic infectious disease caused by Mycobacterium leprae. IL-12 participates in the immune response against M. leprae by regulating T cell differentiation into the Th1-type response. Several single nucleotide polymorphisms have been identified in the IL-12 gene such as 3′UTR 1188 A/C polymorphism, which is associated with different diseases. However, the relationship of this polymorphism with the immune response in leprosy has not been explored. In this case–control study, we evaluated 44 patients with lepromatous leprosy (LL) and 51 healthy subjects (HS). We aimed to determine the relationship between 3′UTR 1188 A/C polymorphism of IL-12 p40, mRNA expression, and soluble IL-12 concentration in LL patients and HS. Genotype frequencies were 41% A/A, 36% A/C, and 23% C/C in LL patients, and 47% A/A, 49% A/C, and 4% C/C in HS ( p < 0.05). LL patients had a lower mRNA expression of IL-12 p40 gene, whereas HS had a higher expression level. Soluble IL-12 p40 concentration was higher in LL patients than in HS ( p < 0.05). IL-12 p70 concentration did not differ between groups, and IL-12 p40 concentration was not significantly correlated with mRNA expression in either group. These data suggest that IL-12 p40 3′UTR 1188 A/C polymorphism is associated with greater susceptibility to lepromatous leprosy in patients from western Mexico, independently of IL-12 p40 and p70 expression levels.

Mycobacterium tuberculosisheat shock protein 60 modulates immune response to PPD by manipulating the surface expression of TLR2 on macrophages

The T-helper (Th) 1 T-cell response to purified protein derivative (PPD) is known to be suppressed in tuberculosis patients which favours intracellular survival of the bacilli. We demonstrate that the Mycobacterium tuberculosis heat shock protein 60 (Mtbhsp60) plays an important role to skew the anti-PPD T-cell response towards the Th2 type when macrophages were used as antigen presenting cells. We found that the PPD-induced IL-12 p40 was downregulated in macrophages by Mtbhsp60. The Mtbhsp60 preferentially induced Toll-like receptor (TLR) 2 without affecting TLR4 expression on macrophages. Interaction of Mtbhsp60 with TLR2 resulted in significant suppression of nuclear c-rel and consequently IL-12 p40 levels in PPD-activated macrophages. Our findings reveal a unique role of the Mtbhsp60 favouring development of Th2 type response by upregulating surface expression of TLR2 on macrophages which could be a survival strategy adopted by the bacilli.

Functional deficiencies of granulocyte-macrophage colony stimulating factor and interleukin-3 contribute to insulitis and destruction of β cells

AbstractThe pathogenesis of type 1 diabetes (T1D) involves the immune-mediated destruction of insulin-producing β cells in the pancreatic islets of Langerhans. Genetic analysis of families with a high incidence of T1D and nonobese diabetic (NOD) mice, a prototypical model of the disorder, uncovered multiple susceptibility loci, although most of the underlying immune defects remain to be delineated. Here we report that aged mice doubly deficient in granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3) manifest insulitis, destruction of insulin-producing β cells, and compromised glucose homeostasis. Macrophages from mutant mice produce increased levels of p40 after LPS stimulation, whereas concurrent ablation of interferon-γ (IFN-γ) ameliorates the disease. The administration of antibodies that block cytotoxic T lymphocyte associated antigen-4 (CTLA-4) to young mutant mice precipitates the onset of insulitis and hyperglycemia. These results, together with previous reports of impaired hematopoietic responses to GM-CSF and IL-3 in patients with T1D and in NOD mice, indicate that functional deficiencies of these cytokines contribute to diabetes.

Dysregulated expression of interleukin-23 and interleukin-12 subunits in systemic lupus erythematosus patients

The aim of this study was to investigate the regulation of interleukin (IL)-12 and IL-23 expression in the autoimmune disease, systemic lupus erythematosus (SLE). mRNA from healthy subjects and SLE patients were prepared from peripheral blood mononuclear cells (PBMC) and quantitative real-time polymerase chain reaction was performed to quantify IL-23 specific subunit P19, IL-12 specific subunit P35, and their common subunit P40. IL-12 specific subunit P35 mRNA expression in untreated and treated SLE patients was significantly lower than healthy controls (P = 0.015 and 0.000, respectively). Compared with untreated SLE patients, treatment of SLE patients with corticosteroids or corticosteroids plus another immunosuppressor significantly suppressed P40 and P19 expression (P = 0.002 and 0.015, respectively). The mRNA levels of p19, p40, and p35 in active SLE patients (SLEDAT > 10) were significantly higher compared with those in the inactive SLE patients (SLEDAI <or= 10) (P = 0.000, 0.000, and 0.017, respectively). These results suggest that deficiency of IL-12 and possibly upregulation of IL-23 may contribute to SLE pathogenesis and both cytokines may be therapeutic targets in SLE.

Human Granulocytic Anaplasmosis and Macrophage Activation

Patients with human granulocytic anaplasmosis present with fever, thrombocytopenia, leukopenia, and an elevated aspartate transaminase level. Clinical and histopathologic features of severe disease suggest macrophage activation. Twenty-nine patients with human granulocytic anaplasmosis had higher ferritin, interleukin-10, interleukin-12 p70, and interferon- gamma levels than did control subjects matched for age and sex; severity correlated with triglyceride, ferritin, and interleukin-12 p70 levels. Several severely affected patients had cases that fulfilled macrophage activation syndrome diagnostic criteria. Macrophage activation and excessive cytokine production may belie tissue injury associated with Ananplasma phagocytophilum infection.

Involvement of mast cells in IL-12/23 p40 production is essential for survival from polymicrobial infections

AbstractInterleukin-12 (IL-12), a heterodimeric cytokine (p35/p40) produced mainly from macrophages and dendritic cells, is an important regulator of T-helper 1 cell responses and for host defense. We found that interferon (IFN) consensus sequence binding protein (ICSBP), which is a transcription factor essential for the expression of p40, was expressed in mouse bone marrow–derived mast cells (BMMCs). The transcription levels of p35 and p40 were increased by stimulation of BMMCs with IFN-γ/lipopolysaccharide (LPS). IL-12 was secreted from BMMCs in response to LPS but not by FcϵRI cross-linking. The p40 levels in the peritoneal cavity of mast cell–deficient W/Wv and W/Wv reconstituted with p40−/− BMMCs were significantly lower than those of WBB6F1+/+ and wild-type (WT) BMMC-reconstituted W/Wv in the acute septic peritonitis model. The survival rate of W/Wv reconstituted with p40−/− BMMCs was significantly decreased compared to those of WBB6F1+/+ and WT-BMMC–reconstituted W/Wv, which was due to reduced production of IFN-γ and subsequent impaired activation of neutrophils in the peritoneal cavity. Survival rate of p40−/− mice was also restored by adoptive transfer of WT-BMMCs. These results demonstrate that mast cells play a significant role in the production of IL-12 required for host defense. This is the first report to demonstrate that mast cells are a crucial source of functional IL-12.

Dysregulated expression of interleukin-23 and interleukin-12 subunits in systemic lupus erythematosus patients

The aim of this study was to investigate the regulation of interleukin (IL)-12 and IL-23 expression in the autoimmune disease, systemic lupus erythematosus (SLE). mRNA from healthy subjects and SLE patients were prepared from peripheral blood mononuclear cells (PBMC) and quantitative real-time polymerase chain reaction was performed to quantify IL-23 specific subunit P19, IL-12 specific subunit P35, and their common subunit P40. IL-12 specific subunit P35 mRNA expression in untreated and treated SLE patients was significantly lower than healthy controls (P = 0.015 and 0.000, respectively). Compared with untreated SLE patients, treatment of SLE patients with corticosteroids or corticosteroids plus another immunosuppressor significantly suppressed P40 and P19 expression (P = 0.002 and 0.015, respectively). The mRNA levels of p19, p40, and p35 in active SLE patients (SLEDAT > 10) were significantly higher compared with those in the inactive SLE patients (SLEDAI ≤ 10) (P = 0.000, 0.000, and 0.017, respectively). These results suggest that deficiency of IL-12 and possibly upregulation of IL-23 may contribute to SLE pathogenesis and both cytokines may be therapeutic targets in SLE.

A 91-d Repeated Dose Oral Toxicity Study of PureSorb-Q 40 in Rats

As part of a series of non-clinical studies to evaluate the safety of PureSorb-Q(TM)40 (Water-soluble type CoQ(10) powder, CoQ(10) content is 40 w/w%; hereinafter referred to as P40), male and female rats were treated orally by gavage with P40 once a day for 91 d, and its repeated dose toxicity was assessed. Control animals were treated with a 0.5 w/v% solution of methylcellulose, the vehicle for P40. Each test group consisted of 6 animals of each sex. No adverse effects of P40 were noted in general signs, body weight, food consumption, ophthalmological examination, urinalysis, hematological examination, blood chemical analysis, necropsy, organ weights, or histopathological examination in animals of either sex. From these results, the no observed adverse effect level of P40 was estimated at 2,000 mg/kg in both sexes of rats under the conditions of the present study, and P40 was confirmed to be a food material whose safety is high.

Nitric oxide inhibits interleukin-12 p40 through p38 MAPK-mediated regulation of calmodulin and c-rel

In activated macrophages, the rel/NF-κB transcription factors are known to play important roles in interleukin-12 (IL-12) p40 regulation by nitric oxide (NO). However, the relative contributions of these factors are not well understood. Here, we describe a dominant role for c-rel involving p38 mitogen-activated protein kinase (p38 MAPK) and calmodulin (CaM) protein in NO-mediated IL-12 p40 inhibition in activated macrophages. Inhibition of NO production by aminoguanidine increased, whereas sodium nitroprusside (SNP; an exogenous NO generator) reduced, nuclear c-rel levels in LPS + IFN-γ-activated RAW 264.7 macrophages. Overexpression of c-rel but not p65 NF-κB increased IL-12 p40 during NO treatment. The p38 MAPK phosphorylation is increased by NO, and inhibition of p38 MAPK in SNP-treated macrophages by SB203580 or transient expression of a dominant-negative mutant of p38 MAPK upregulated both nuclear c-rel and IL-12 p40 levels, indicating that NO targeted the p38 MAPK pathway to inhibit c-rel and IL-12 p40. Cytoplasmic CaM level was increased by NO, and SB203580 decreased the CaM level in NO-exposed macrophages. Inhibition of CaM activity by trifluoperazine rescued the inhibitory effect of NO on c-rel and IL-12 p40. Our findings indicate that c-rel plays an important role in NO-mediated inhibition of IL-12 p40 and is regulated by p38 MAPK through CaM protein.

The expression of interleukin-23 (p19/p40) and inteleukin-12 (p35/p40) in psoriasis skin

In order to investigate the mRNA expression and function of interleukin-23 (p19/p40) and interleukin-12 (p35/p40) in the psoriatic lesion, no-lesion and normal human skin, reverse transcriptase-polymerase chain reaction (RT-PCR) was used to detect the expression of IL-23 (p19/p40) and IL-12 (p35/p40). The results showed that the expression of IL-23p19 mRNA and p40 (IL-12/IL-23) mRNA were higher in psoriatic lesion than those of non-lesional skin and normal skin. The levels of IL-23p19 mRNA and p40 (IL-12/IL-23) mRNA were higher in psoriatic non-lesional skin than normal skin. However, no significant difference was found in the level of IL-12p35 mRNA among the psoriatic lesional skin, non-lesional skin and normal skin. It was suggested that IL-23 might be more important in the pathogenesis of psoriasis than IL-12.

Effect of granulocyte colony‐stimulating factor on IL‐12 p40 production during chemotherapy for B‐cell lineage non‐Hodgkin's lymphoma patients

Interleukin (IL)-12 is a 70-kDa cytokine comprised of two disulfide-linked proteins (p35 and p40) and is essential for the initiation of effective immune response. Granulocyte-colony stimulating factor (G-CSF) affects the balance in the production of anti-inflammatory cytokines. We investigated the serum IL-12 p40 and IL-12 Mix (p40 and p70) production in 28 patients with B-cell lineage non-Hodgkin's lymphoma (NHL) treated with chemotherapy (e.g., CHOP regimen) with or without G-CSF administration and eight healthy volunteers. We found that serum levels of IL-12 p40 (191.2 +/- 150.0 pg/mL) and IL-12 Mix (277.4 +/- 274.5 pg/mL) in the patients before chemotherapy were higher than those in the healthy volunteers (IL-12 p40: 76.4 +/- 25.3 pg/mL, IL-12 Mix: 48.5 +/- 33.4 pg/mL) (P = 0.04 and 0.02, respectively). Next, we examined the serum IL-12 p40 and IL-12 Mix levels in nine patients receiving chemotherapy with administration of G-CSF (CG group, n = 9) and without G-CSF (C group, n = 9). Serum IL-12 p40 and IL-12 Mix levels were decreased on 10 d after chemotherapy in both groups, and those in CG groups were significantly lower than those in C group. These results indicated that administration of G-CSF decreased serum IL-12 p40 and IL-12 Mix levels. Overall survival (OS) at 24 months was not significantly different in the two groups (58.3% in group C vs. 80.0% in group CG, P = 0.67). However, the survival rate of patients at clinical stages III and IV in CG group (n = 6, 66.0%) was significantly better than that of patients in C group (n = 4, 25.0%) (P = 0.02). Long-term administration of G-CSF appears to influence the survival rate by reducing immunosuppressive IL-12 p40 production.

Role of IL-12B Promoter Polymorphism in Adamantiades–Behcet's Disease Susceptibility: An Involvement of Th1 Immunoreactivity against Streptococcus Sanguinis Antigen

Adamantiades-Behcet's disease (ABD) is a chronic inflammatory multisystem disorder. Although the precise etiology is unclear, high prevalence of human leukocyte antigen (HLA)-B51 predisposition and predominantly involved T-helper type 1 cells (Th1)-type proinflammatory cytokines and extrinsic Streptococcal infection suggest a substantial association with an immunogenetic basis and strengthens the hypothesis that IL-12, a potent inducer of Th-1 immune reaction, is a putative candidate in its pathogenesis. These clinicopathological findings led us to examine interleukin 12 p40 (IL-12B) promoter polymorphism, for which the 4-base pair (bp) heterozygous insertion has been shown to affect the gene transcription and subsequent protein production. We analyzed IL-12B promoter genotypes in 194 Japanese subjects (92 with ABD and 102 normal controls) by PCR-based restriction enzyme digestion. The frequency of the insertion heterozygosity was significantly higher in patients than in controls (49/92, 53.3% vs 39/102, 38.2%, respectively). Comparing these with HLA haplotype data, this trend was more significant in HLA-B51-negative patients (29/42, 69.0% vs 20/50, 40.0%; P = 0.005). As assessed by semiquantitative reverse transcription-PCR and ELISA, stimulation with Streptococcal antigens specifically increased expression of IL-12 p40 mRNA and protein, in conjunction with IL-12 p70 induction, in peripheral blood mononuclear cells from heterozygous patients. Our results provide evidence for anti-bacterial host response toward Th1-immunity mediated by IL-12 in patients with ABD, and the possible insight into the genetic susceptibility that is independent of HLA background.