Sclerostin and bone turnover markers response to cycling and running at the same moderate-to-vigorous exercise intensity in healthy men.

BACKGROUND: Recreational cycling is a popular activity which stimulates and improves cardiovascular fitness. The corresponding benefits for bone are unclear. PURPOSE: This study examined the effect of running (high-impact) vs. cycling (low-impact), at the same moderate-to-vigorous exercise intensity, on markers of bone formation (N-terminal propeptide of type I collagen, PINP) and bone resorption (C-telopeptide of type I collagen, CTX-1), a non-collagenous bone remodeling marker (osteocalcin), as well as bone-modulating factors, including parathyroid hormone (PTH), irisin (myokine) and sclerostin (osteokine). METHODS: Thirteen healthy men (23.7 ± 1.0 y) performed two progressive exercise tests to exhaustion (peak VO2) on a cycle ergometer (CE) and on a treadmill (TM). On subsequent separate days, in randomized order, participants performed 30-min continuous running or cycling at 70% heart rate reserve (HRR). Blood was drawn before, immediately post- and 1 h into recovery. RESULTS: PTH transiently increased (CE, 51.7%; TM, 50.6%) immediately after exercise in both exercise modes. Sclerostin levels increased following running only (27.7%). Irisin increased following both running and cycling. In both exercise modes, CTX-1 decreased immediately after exercise, with no significant change in PINP and osteocalcin. CONCLUSION: At the same moderate-to-vigorous exercise intensity, running appears to result in a greater transient sclerostin response compared with cycling, while the responses of bone markers, PTH and irisin are similar. The longer-term implications of this differential bone response need to be further examined.

Evaluation of an immunological score to assess the risk of severe infection in heart recipients.

BACKGROUND: We previously reported how specific humoral and cellular immunological markers that are readily available in clinical practice can be used to identify heart transplant recipients (HTR) at risk of developing severe infections. In this study, we perform an extended analysis to identify immunological profiles that could prove to be superior to individual markers in assessing the risk of infection early after heart transplantation. METHODS: In a prospective follow-up study, we evaluated 100 HTR at 1 week after transplantation. Laboratory tests included determination of immunoglobulin (Ig) levels (IgG, IgA, IgM), complement factors (C3 and C4), and lymphocyte subsets (CD3+, CD4+, CD8+ T cells, B cells, and natural killer [NK] cells). The prevalence of infection during the first 3 months was registered at scheduled visits after transplantation. Severe infections were defined as all infections requiring hospitalization and intravenous antimicrobial therapy. RESULTS: During follow-up, 33 patients (33%) developed severe infections. The individual risk factors of severe infection, according to the Cox regression analysis, were as follows: IgG <600 mg/dL (hazard ratio [HR], 2.41; 95% confidence interval [CI], 1.21-4.78; P = 0.012), C3 <80 mg/dL (HR, 4.65; 95% CI, 2.31-9.38; P < 0.0001), C4 <18 mg/dL (HR 2.30, 95% CI, 1.15-4.59; P = 0.018), NK count <30 cells/µL (HR 4.07, 95% CI, 1.76-9.38; P = 0.001), and CD4 count <350 cells/µL (HR, 3.04; 95% CI, 1.47-6.28; P = 0.0027). An immunological score was created. HRs were used to determine the number of points assigned to each of the 5 previously mentioned individual risk factors. The score was obtained from the sum of these factors. In the multivariate Cox regression analysis, the immunological score was useful for identifying patients at risk of infection and was the only variable that maintained a significant association with the development of infection, after adjustment for the 5 individual factors. CONCLUSION: Patients with an immunological score ≥13 were at the highest risk of severe infections (HR, 9.29; 95% CI, 4.57-18.90; P < 0.0001). This score remained significantly associated with the risk of severe infection after adjustment for clinical risk factors of infection. An immunological score was useful for identifying HTR at risk of developing severe infections. If this score is validated in multicenter studies, it could be easily introduced into clinical practice.

Outcomes of splenectomy in patients with common variable immunodeficiency (CVID): a survey of 45 patients.

Splenectomy has been used in patients with common variable immunodeficiency disorders (CVID), mainly in the context of refractory autoimmune cytopenia and suspected lymphoma, but there are understandable concerns about the potential of compounding an existing immunodeficiency. With increasing use of rituximab as an alternative treatment for refractory autoimmune cytopenia, the role of splenectomy in CVID needs to be re-examined. This retrospective study provides the largest cohesive data set to date describing the outcome of splenectomy in 45 CVID patients in the past 40 years. Splenectomy proved to be an effective long-term treatment in 75% of CVID patients with autoimmune cytopenia, even in some cases when rituximab had failed. Splenectomy does not worsen mortality in CVID and adequate immunoglobulin replacement therapy appears to play a protective role in overwhelming post-splenectomy infections. Future trials comparing the effectiveness and safety of rituximab and splenectomy are needed to provide clearer guidance on the second-line management of autoimmune cytopenia in CVID.

Flow cytometry analysis with a new FITC-conjugated monoclonal antibody-3E12 for HLA-B*57:01 rapid screening in prevention of abacavir hypersensitivity in HIV-1-infected patients.

BACKGROUND: Rapid screening for the detection of HLA-B*57:01 in the prevention of abacavir hypersensitivity in HIV-1-infected patients is a hallmark for clinical services. OBJECTIVE: The aim of this work was to analyze the utility of flow cytometry with a new FITC-conjugated B-17 monoclonal antibody (mAb3E12) for HLA-B*57:01 screening in a Spanish cohort of 577 HIV-1+ individuals. METHODS: Cryopreserved peripheral blood mononuclear cell samples from HIV-1+ individuals were analyzed by flow cytometry with the mAb 3E12 that recognizes both HLA-B*57 and HLA-B*58 alleles (members of the group specificity, HLA-B17). Patients' DNA samples had been previously typed for HLA-B*57:01 with PCR-SSO or PCR-SSP and additional DNA sequencing (EPI Study). The results obtained by flow cytometry were compared with the results obtained by the DNA-PCR techniques. RESULTS: By flow cytometry, 46 samples (7.97%) were positive for HLA-B17, 530 (91.86%) were negative, and 1 (0.17%) was undetermined. All samples found negative by flow cytometry were negative for HLA-B*57:01 by DNA-PCR. Of the HLA-B17 positive samples, 31 (67.4%) were positive for HLA-B*57:01, 2 (3.25%) were positive for HLA-B*57:03, 11 (26.1%) were positive for HLA-B*58, and 2 (3.25%) were negative for both HLA-B*57 and HLA-B*58 antigens. The undetermined sample was negative for HLA-B*57 and HLA-B*58 alleles by DNA-PCR. CONCLUSIONS: This study shows that flow cytometry with mAb3E12 is a highly sensitive method (no false negatives) to implement prior to DNA-PCR analysis for rapid screening of HLA-B*57:01. Additional confirmation by molecular HLA typing method would be required in less than 10% of the cohort of HIV-1-infected individuals.

Restoration of humoral immunity after intravenous immunoglobulin replacement therapy in heart recipients with post-transplant antibody deficiency and severe infections.

IgG hypogammaglobulinemia is a risk factor for infection in heart recipients. We assessed reconstitution of humoral immunity after non-specific intravenous immunoglobulin (IVIg) replacement therapy administered to treat secondary IgG hypogammaglobulinemia in heart recipients with severe infections. The study population comprised 55 heart recipients who were administered IVIg (IVIg group) and 55 heart recipients with no severe infectious complications (control group). An event was defined as a severe infection requiring intravenous drug therapy during the first year after transplantation. The IVIg protocol comprised non-specific 5% pasteurized IVIg at a dose of 300-400 mg/kg/months. IgG titers were lower in the IVIg group than in controls at seven d (577 vs. 778 mg/dL, p < 0.001) and at one month (553 vs. 684, p = 0.003). After IVIg therapy, IgG concentrations were similar in both groups at three months (681 vs. 737, p = 0.25) and at six months (736 vs. 769, p = 0.46). At three months, the IVIg group had higher levels of antitetanus toxoid and anti-HBs (ELISA, 2.07 ± 2.11 vs. 0.60 ± 1.24 mg/dL [p = 0.003] and 42 ± 40 vs. 11 ± 31 IU/mL [p = 0.005], respectively) than controls. The mean number of infectious complications was significantly lower after IVIG therapy in the IVIG group. IVIg was associated with restoration of humoral immunity in heart recipients with post-transplant IgG hypogammaglobulinemia and severe infections.

Decreased levels of serum complement C3 and natural killer cells add to the predictive value of total immunoglobulin G for severe infection in heart transplant recipients.

BACKGROUND: Infection remains a source of mortality in heart recipients. We previously reported that post-transplant immunoglobulin G (IgG) quantification can help identify the risk for infection. We assessed whether other standardized parameters of humoral and cellular immunity could prove useful when identifying patients at risk of infection. METHODS: We prospectively studied 133 heart recipients over a 12-month period. Forty-eight patients had at least one episode of severe infection. An event was defined as an infection requiring intravenous antimicrobial therapy. RESULTS: Cox regression analysis revealed an association between the risk of developing infection and the following: lower IgG2 subclass levels (day 7: relative hazard [RH] 1.71; day 30: RH 1.76), lower IgA levels (day 7: RH 1.61; day 30: RH 1.91), lower complement C3 values (day 7: RH 1.25), lower CD3 absolute counts (day 30: RH 1.10), lower absolute natural killer [NK] cell count (day 7: RH 1.24), and lower IgG concentrations (day 7: RH 1.31; day 30: RH 1.36). Cox regression bivariate analysis revealed that lower day 7 C3 levels, IgG2 concentration, and absolute NK cell count remained significant after adjustment for total IgG levels. CONCLUSIONS: Data suggest that early immune monitoring including C3, IgG2, and NK cell testing in addition to IgG concentrations is useful when attempting to identify the risk of infection in heart transplant recipients.

Sublingual therapeutic immunization with a polyvalent bacterial preparation in patients with recurrent respiratory infections: immunomodulatory effect on antigen-specific memory CD4+ T cells and impact on clinical outcome.

Recurrent respiratory tract infections (RRTIs) are common clinical conditions in individuals with alterations of the immune function. A prospective open pilot study in a cohort of patients with RRTIs has been performed to assess whether sublingual immunization with a polyvalent bacterial vaccine could exert an immunomodulatory effect on the antigen-specific immunological responses and have an impact on the clinical outcome. Seventeen patients with RRTIs were recruited. An oral polyvalent bacterial preparation (Bactek®) was administered to all patients daily for 6 months. Immunological assessment was performed at baseline and at the end of immunization. Immunological measurements included: T cell-specific proliferations of CD3+CD4+ and CD3+CD8+ to Bactek® antigens, total immunoglobulin levels, antibodies to pneumococcal polysaccharide and tetanus toxoid and B, T and natural killer (NK) cell subsets. There was a significant increase in the proliferative capacity of CD3+CD4+ T cells specific to Bactek® antigens at month 6 in comparison to baseline (P < 0·0001). A significant increase in total CD3+ T cells was also observed (P < 0·05). No significant differences were observed between baseline and month 6 in levels of total immunoglobulins, specific antibodies and B, T or NK cell subsets. A significant reduction in the patient's rate of RRTIs was observed compared with 1 year prior to initiation of therapy (P < 0·0001). The results demonstrate that long-term administration of a sublingual polyvalent bacterial preparation in patients with RRTIs exerts an immune stimulating effect on CD4+ T helper cell responses to bacterial antigens which could be associated with clinical benefit.

Impaired prostate tumorigenesis in Egr1-deficient mice.

The transcription factor early growth response protein 1 (EGR1) is overexpressed in a majority of human prostate cancers and is implicated in the regulation of several genes important for prostate tumor progression. Here we have assessed the effect of Egr1 deficiency on tumor development in two transgenic mouse models of prostate cancer (CR2-T-Ag and TRAMP). Using a combination of high-resolution magnetic resonance imaging and histopathological and survival analyses, we show that tumor progression was significantly impaired in Egr1-/- mice. Tumor initiation and tumor growth rate were not affected by the lack of Egr1; however, Egr1 deficiency significantly delayed the progression from prostatic intra-epithelial neoplasia to invasive carcinoma. These results indicate a unique role for Egr1 in regulating the transition from localized, carcinoma in situ to invasive carcinoma.

Humoral and cellular immune monitoring might be useful to identify liver transplant recipients at risk for development of infection.

Orthotopic liver transplantation (OLT) is a successful therapy for patients with end-stage liver disease, and infection remains a significant cause of morbidity and mortality for patients undergoing this procedure. To assess humoral and cellular immunity markers as potential risk factors for development of infection, 46 consecutive liver transplant recipients (hepatitis C virus cirrhosis [n=17], alcoholic liver disease [n=15], hepatocellular carcinoma [n=9], autoimmune hepatitis [n=2], and other [n=3]) performed at a single center were prospectively studied. Maintenance therapy included tacrolimus (n=37) or cyclosporine (n=9) and prednisone. During follow-up, 27 patients had at least 1 episode of infection (58.7%). Pre-OLT immunoglobulin G (IgG) hypergammaglobulinemia (relative risk [RR] 2.78; 95% confidence interval [CI], 1.17-6.60, P=0.02), pre-OLT IgA hypergammaglobulinemia (RR 2.77, CI=1.24-6.19, P=0.012), and pre-OLT C3 hypocomplementemia (RR 3.02, CI=1.21-7.55, P=0.018) were associated with an increased risk for development of infection. Monitoring of Ig and complement levels might help to identify the risk of developing infection in OLT.

Humoral and cellular monitoring to predict the development of infection in Crohn's disease patients beginning treatment with infliximab.

Although severe infectious complications are rare, it is important to properly screen patients for predisposing conditions before beginning treatment with infliximab. We assessed immunity markers that might provide prognostic value for the development of infection in Crohn's disease patients after treatment with infliximab. In a prospective study, 34 fistulizing Crohn's disease patients (mean age 37 years) were studied. Patients were scheduled to receive three infusions of infliximab (5 mg/kg) at weeks 0, 2, and 6. Immunologic studies: Serum immunoglobulin (IgG, IgA, IgM), IgG-subclasses, and complement (C3, C4, factor B) determined by nephelometry; CD3+, CD3+CD4+, CD3+CD8+, CD19+, and CD56+CD3- lymphocyte subsets performed by flow cytometry. During a mean follow-up of 56 months, 1 patient had disseminated tuberculosis and 2 patients had severe bacterial infections. The presence of infection was associated with significantly higher IgM (246 vs. 121 mg/dL; Mann-Whitney test, P = 0.01), lower C3 (64 vs. 118, P = 0.02), lower C4 concentrations (12 vs. 25, P = 0.02), and with decreased levels of CD19 B cells (47 vs. 290, P = 0.03) in the baseline study. Further prospective studies in a larger number of patients are suggested to examine whether early monitoring of immunocompetence might help to identify the risk of infection in patients treated with infliximab.

The potential impact of substitutive therapy with intravenous immunoglobulin on the outcome of heart transplant recipients with infections.

Hypogammaglobulinemia has been proposed to be a risk factor for infection after heart transplantation (OHT). Infection is a leading cause of morbility and mortality among these patients. In a retrospective study we analyzed the impact of substitutive therapy with nonspecific intravenous immunoglobulin (IVIG) on the outcomes of heart transplant patients with infections. We analyzed the outcome of 123 consecutive heart transplant recipients in our center from June 1996 to November 2005. Their mean age was 53 years (range = 22 to 69 years), and the mean follow-up = 51 months, (range = 1 to 124 months). Twenty-nine patients with hypogammaglobulinemia (mean serum immunoglobulin G levels = 480 mg/dL) experienced severe infections due to cytomegalovirus (CMV) disease, n = 4; CMV disease + another infection, n = 6; CMV infection, n = 4; CMV infection + other infection, n = 3; pulmonary nocardiosis, n = 2; recurrent pneumonia, n = 2; clostridium-difficile-associated diarrhea, n = 2; pulmonary tuberculosis, n = 1; bacterial infections, n = 5. They were treated with IVIG (400 mg/kg every 21 days) with the goal to reach normal serum immunoglobulin G levels (>700 mg/dL). Overall (n = 123), a logistic regression analysis showed IVIG therapy to be associated with a decreased risk of death [odds ratio (OR) = 0.204, 95% confidence interval (CI) = 0.04 to 0.92, P = .03]. Among patients who developed infections during follow-up (n = 70), IVIG therapy was also associated with a lower risk of death (OR = 0.104, CI = 0.02 to 0.50, P = .0047). When we stratified patients with CMV disease (n = 24) according to the presence (n = 10) or absence (n = 14) of IVIG therapy, the mortality rate of IVIG-treated patients was 20% versus 71% for non-IVIG treated patients [OR = 0.06, CI = 0.0060 to 0.63, P = .01]. The use of nonspecific IVIG in OHT with hypogammaglobulinemia and infections might reduce the risk of death. Randomized studies in a larger cohort of patients are necessary to confirm these results.

Impaired anti-pneumococcal polysaccharide antibody production and invasive pneumococcal infection following heart transplantation.

An increased risk of invasive pneumococcal infection has been described among adult heart transplant (HT) recipients. Vaccination has been recommended before HT but the appropriate time for revaccination is not known. In a preliminary analysis of a prospective study involving a cohort of 32 HT recipients receiving daclizumab and triple immunosuppresion therapy, a progressive decline in pneumococcal polysaccharide antibody (anti-PPS) levels was observed during the first year after HT. One of the patients who was found to have a decrease in the levels of anti-PPS developed severe pneumococcal meningitis 20 months after HT. Before HT he had received non-conjugated 23-valent pneumococcal vaccine and showed a normal post-immunization anti-PPS production. The data suggest that long-term immunologic monitoring might be useful to recognize impairment of antibody responses under immunosuppressive therapy in HT.

[Systemic autoimmune disease in patients with uveitis]. / Enfermedad autoinmune sistémica en pacientes con uveítis.

OBJECTIVE: A descriptive study was conducted on patients with uveitis to determine the frequency of associated autoimmune systemic diseases. METHODS: 64 patients with uveitis were studied. The patients were not known to have an underlying autoimmune systemic disease prior to the diagnosis of uveitis. All patients had the following immunological tests performed: serum immunoglobulins, complement components, circulating immune complexes (CIC), antinuclear antibodies (ANA), anti-neutrophil cytoplasmic antibodies (ANCA), anti-cardiolipin antibodies (ACA) and major histocompatibilty complex antigens. RESULTS: A relationship with a sub-clinical autoimmune systemic disorder could be presumed in eleven cases (17.2%). This was defined by positive autoantibodies (ANA, ANCA or ACA) in the presence of complement consumption, hyper-gammaglobulinemia or increased CIC without clinical criteria of a defined autoimmune disease. A definite association with systemic autoimmune disease was defined in four patients (6.25%). The observed autoimmune systemic diseases were Sjögren's syndrome (n=2, 3.13%), anti-phospholipid syndrome associated with lupus-like disease (n=1, 1.6%), and systemic vasculitis (n=1, 1.6%). Lupus-like disease (n=4, 6.25%) was also observed. CONCLUSION: In a significant proportion of patients with uveitis an autoimmune systemic disorder may be present and should be looked for.

Potential Immunomodulatory Role of Specific Anticytomegalovirus Intravenous Immunoglobulin in Heart Recipients.

BACKGROUND: Specific anticytomegalovirus (anti-CMV) intravenous immunoglobulin (IVIG) has the potential to influence the immune response, but its complex mode of action has not been well evaluated. METHODS: An immunologic study of 6 CMV-seronegative heart transplant patients receiving anti-CMV prophylaxis with the use of ganciclovir and CMV-IVIG (150 mg/kg within 24 hours after transplantation and 100 mg/kg on days 2, 7, 14, 22, 35, 56, and 77 after transplantation) was performed in a single center. Lymphocyte subsets were evaluated by means of 4-color flow cytometry at the time of inclusion in the waiting list and at 3 months after transplantation. RESULTS: High-risk heart recipients receiving CMV-IVIG showed a clear reduction in the frequency of activated CD4+CD38+DR+ T-helper cells at 3 months after transplantation compared with a group of 27 untreated control subjects who received only anti-CMV prophylaxis with the use of ganciclovir. In this study, an increase of CD19+CD27-IgM+IgD+ naïve B cells was also observed in seronegative recipients after prophylaxis with the use of CMV-IVIG but not in control subjects. None of the CMV-IVIG-treated recipients developed acute cellular rejection during the 1st 6 months after transplantation. CONCLUSIONS: The immune modulation of activated CD4+ lymphocyte and of naïve B-cell subsets after CMV-IVIG use should be further evaluated in future prospective studies with higher numbers of patients.

Partial response to anti-CD20 monoclonal antibody treatment of severe immune thrombocytopenic purpura in a patient with common variable immunodeficiency.

Immune thrombocytopenic purpura (ITP), alone or in combination with autoimmune hemolytic anemia (Evans syndrome) and/or autoimmune neutropenia, is frequent in patients with common variable immunodeficiency (CVID). A 34-year-old man with CVID had long-standing unresponsive ITP. The patient had a 9-year history of CVID on substitutive therapy with intravenous immunoglobulin (IVIG). The clinical course of CVID was complicated with refractory fistulizing inflammatory bowel disease, nodular regenerative hyperplasia of the liver, splenomegaly, severe portal hypertension, and hypercatabolism of IgG. ITP was refractory to medical therapy, including different combinations of corticosteroids, high-dose IVIG, azathioprine, and vincristine. Splenectomy was not performed because of severe portal hypertension. He received a total five doses of rituximab, a monoclonal antibody directed against CD20 antigen, at a dose of 375 mg/m(2). After an initially slow response, his platelet count increased to more than 50,000/microL by the fourth week of infusion. Therapy was well tolerated, and B lymphocytes were effectively depleted from the peripheral blood. The patient was completely tapered off glucocorticoids and maintained platelets at above 40,000/microL. The patient has not taken immunosuppressive agents for 11 months. Early treatment with rituximab might be an option for patients with CVID and ITP that do not respond to other treatments or for patients for whom a splenectomy is contraindicated.