Effect of vitamin D3 on phagocytic potential of macrophages with live Mycobacterium tuberculosis and lymphoproliferative response in pulmonary tuberculosis

Evaluation of serum 25-hydroxyvitamin D, C-reactive protein, and haptoglobin as biomarkers in dogs newly diagnosed with histoplasmosis

BACKGROUND

Serum 25-hydroxyvitamin (OH)D, C-reactive protein (CRP), and haptoglobin are useful biomarkers in various infectious diseases and inflammatory disorders in dogs, but their utility in histoplasmosis is unknown.

OBJECTIVE

Determine if serum 25(OH)D, CRP, and haptoglobin concentrations are different in dogs with histoplasmosis compared to healthy controls and whether serum globulin, albumin, CRP, or haptoglobin are associated with 25(OH)D concentration.

ANIMALS

Twenty-two client-owned dogs (histoplasmosis, n = 12; controls, n = 10).

METHODS

Prospective case-control study. Dogs with histoplasmosis were categorized as pulmonary, disseminated, or gastrointestinal (GI) tract. Serum 25(OH)D was measured using modified high-performance liquid chromatography (HPLC). Serum CRP and haptoglobin were measured with ELISA assays.

RESULTS

Dogs with histoplasmosis were grouped as disseminated (n = 8) and GI tract (n = 4). No dogs had pulmonary tract involvement alone. Dogs with histoplasmosis (median, interquartile range [IQR]; 11.6 ng/mL, 16.8) had lower serum 25(OH)D concentrations than controls (35.7 ng/mL, 17.6; P < .001). Serum CRP and haptoglobin concentrations were higher in dogs with histoplasmosis (CRP: median, IQR; 63.5 mg/L, 37.1 and haptoglobin: 459.7 mg/dL, 419.6) than controls (CRP: 1.9 mg/L, 2; P < .001 and haptoglobin: 85.5 mg/dL, 106.7; P = .003). Serum 25(OH)D concentration was positively associated with fold change in serum albumin concentration (ρ = 0.77; P < .001), and negatively associated with fold change in serum globulin (ρ = -0.61; P = .003) and CRP concentrations (ρ = -0.56; P = .01).

CONCLUSION AND CLINICAL IMPORTANCE

Assay of serum 25(OH)D, CRP, and haptoglobin could have clinical value in dogs with histoplasmosis.

Serum 25-hydroxyvitamin D concentrations in dogs with coccidioidomycosis and variables associated with extent of clinically evident disease

BACKGROUND

Clinicopathologic variables predictive of disseminated coccidioidomycosis are known in humans but have not been explored in dogs. Serum 25-hydroxyvitamin (OH)D correlates with severity of disease of various etiologies in dogs but its role in coccidioidomycosis is unknown.

OBJECTIVE

Determine whether serum 25(OH)D concentrations are different in dogs with coccidioidomycosis compared with healthy controls and if clinicopathologic variables are associated with extent of disease.

ANIMALS

Thirty-five dogs with coccidioidomycosis (pulmonary, n = 13; disseminated, n = 15; uncharacterized, n = 7), and 25 healthy control dogs.

METHODS

Prospective cohort study. Serum 25(OH)D and C-reactive protein (CRP) concentrations were measured with modified-HPLC and a commercial ELISA kit, respectively.

RESULTS

There was no difference in 25(OH)D concentrations between dogs with coccidioidomycosis (median, interquartile range [IQR]; 31.9 ng/mL, 23.3-49.2) and controls (29.5 ng/mL, 25.6-40.8, P = .73). Serum 25(OH)D concentration was lower in dogs with coccidioidomycosis and IgG titers ≥1:32 than dogs with titers below this cut-off (P = .02). Dogs with IgG titers ≥1:32 were more likely to have disseminated disease (OR, 7.5; 95% CI: 1.1-68; P = .03). Serum CRP concentrations were higher in dogs with IgG titers ≥1:16 (median, IQR; 4474.8 ng/mL, 2885.8-8236.1) than in those below this cut-off (151.2 ng/mL, 30.4-2907.3; P = .02). There was a significant inverse association between serum 25(OH)D and CRP at 25(OH)D concentrations ≤33 ng/mL.

CONCLUSION AND CLINICAL IMPORTANCE

Serum 25(OH)D concentration was lower for dogs with IgG titers ≥1:32, indicating a potential association between semi-quantitative titers and 25(OH)D concentrations in dogs with coccidioidomycosis. IgG titers ≥1:32 yielded higher odds of disseminated disease, but was inadequate as a standalone test to determine form of disease.

Influence of vitamin D supplementation on immune function of healthy aging people: A pilot randomized controlled trial

OBJECTIVES

This study aims to investigate the influence of vitamin D supplementation on immune function of healthy older adults.

MATERIALS AND METHODS

Designed as a randomized controlled trial, 21 participants (55-85 years) completed the study during May-November 2018 in Coventry, England. The participants were randomized into vitamin D or the control group, stratified by age, gender and body mass index. The vitamin D group (n = 12) took vitamin D3 tablets of 1,000 IU/day for 12 weeks plus vitamin D education leaflet, while the control group (n = 9) were only provided with the leaflet. At baseline, 6 and 12 weeks, plasma 25(OH)D levels and immunological and metabolic parameters including phagocytic activity of granulocytes and monocytes, tumor necrosis factor, interleukin 6, lymphocyte subsets and fasting blood glucose and lipid were measured. Dietary vitamin D intake was analyzed at baseline and week 12. Data were presented as mean ± SD. Two-way repeated measures ANOVA and independent t-test were used to analyze the data.

RESULTS

At baseline, 42.9% of the participants were vitamin D deficiency (25(OH)D < 25 nmol/L), only 10% achieved a level of 25(OH)D > 50 nmol/L. Overweight/obese participants (n = 9) had significantly lower mean plasma 25(OH)D concentration (22.3 ± 8.7 nmol/L) than normal weight participants (48.1 ± 34.3 nmol/L) (P = 0.043). There was a significant increase in plasma 25(OH)D concentration in vitamin D group compared with that in control group (P = 0.002) during the intervention period. The plasma 25(OH)D concentration in vitamin D group was increased at 6 weeks (from 38.4 ± 37.0 nmol/L at baseline to 51.0 ± 38.2 nmol/L) with little change observed between 6 and 12 weeks (51.8 ± 36.4 nmol/L). The plasma creatinine concentration in vitamin D group was significantly decreased compared with the control group (P = 0.036) (79.8 ± 7.0 μmol/L at baseline vs 75.1 ± 5.4 μmol/L at week 12). No significant effect of vitamin D supplementation was determined on immunological parameters.

CONCLUSION

Vitamin D deficiency is common among the aging population in the UK even during the summertime. Vitamin D supplementation at 1,000 IU/day for 12 weeks significantly increased plasma 25(OH)D concentration but showed no effect on metabolic and immunological parameters except decreased plasma creatinine.

Bovine Immunity and Vitamin D3: An Emerging Association in Johne's Disease

Mycobacterium avium subspecies paratuberculosis (MAP) is an environmentally hardy pathogen of ruminants that plagues the dairy industry. Hallmark clinical symptoms include granulomatous enteritis, watery diarrhea, and significant loss of body condition. Transition from subclinical to clinical infection is a dynamic process led by MAP which resides in host macrophages. Clinical stage disease is accompanied by dysfunctional immune responses and a reduction in circulating vitamin D₃. The immunomodulatory role of vitamin D₃ in infectious disease has been well established in humans, particularly in Mycobacterium tuberculosis infection. However, significant species differences exist between the immune system of humans and bovines, including effects induced by vitamin D₃. This fact highlights the need for continued study of the relationship between vitamin D₃ and bovine immunity, especially during different stages of paratuberculosis.

Serum 25-hydroxyvitamin D concentrations and mortality in dogs with blastomycosis

Blastomycosis is a prominent fungal disease in the United States. Vitamin D status has been found to be altered in critical illness and various infectious diseases. The objectives of this study were to compare serum 25-hydroxyvitamin D (25[OH]D) concentrations in dogs with blastomycosis and healthy controls, to assess the change in serum 25(OH)D concentrations in dogs with blastomycosis after 30 days of treatment, and to determine if baseline serum 25(OH)D concentrations in dogs with blastomycosis were associated with in-hospital, 30-day, or end-of-study mortality. In this prospective cohort study, 19 dogs newly diagnosed with blastomycosis had serum 25(OH)D concentrations measured with a commercially available validated radioimmunoassay at the time of diagnosis and 30 days after start of treatment. These values were compared to 24 healthy control dogs. Serum 25(OH)D concentrations at the time of diagnosis were lower in dogs with blastomycosis (median, 203 nmol/L; range, 31-590 nmol/L) than in clinically healthy control dogs (259.5 nmol/L, 97-829 nmol/L; P = 0.01). Despite clinical improvement, there was no significant change in serum 25(OH)D concentrations from baseline to 30-day follow-up. Dogs with baseline serum 25(OH)D concentrations <180.5nmol/L had a greater odds of death during hospitalization (odds ratio [OR], 15.0; 95% confidence interval [CI], 1.4-191.3; P = 0.04) and at 30 days follow-up (OR, 30.0; 95% CI, 2.5-366.7; P = 0.006). These findings highlight the need for further studies evaluating the prognostic value of vitamin D status in dogs with blastomycosis at diagnosis and throughout treatment and remission.

Nuclear receptors, the aryl hydrocarbon receptor, and macrophage function

Nuclear receptors (NRs) are key regulators of innate immune responses and tissue homeostasis. Evidence indicates that NRs significantly impact steady-state immune regulation, uptake and processing of apoptotic cells, tolerance induction, and control of inflammatory immunity. In this review, we describe our current understanding of the NR activity for balancing inflammation and tolerance, the signaling cascade inducing the NR activation and functional responses, and different mechanisms of the NR-driven immune effects in the context of autoimmune diseases. We further describe the ligand-activated transcription factor the aryl hydrocarbon receptor (AhR) that exhibits analogous functionality. Moreover, we will discuss the putative role of NRs and AhR in immune regulation and disease pathogenesis providing a rationale for therapeutic targeting as a unique opportunities in the clinical management of autoimmune diseases.

Comparative host transcriptome in response to pathogenic fungi identifies common and species-specific transcriptional antifungal host response pathways

Candidiasis, aspergillosis, and mucormycosis cause the majority of nosocomial fungal infections in immunocompromised patients. Using an unbiased transcriptional profiling in PBMCs exposed to the fungal species causing these infections, we found a core host response in healthy individuals that may govern effective fungal clearance: it consists of 156 transcripts, involving canonical and non-canonical immune pathways. Systematic investigation of key steps in antifungal host defense revealed fungal-specific signatures. As previously demonstrated, Candida albicans induced type I and Type II interferon-related pathways. In contrast, central pattern recognition receptor, reactive oxygen species production, and host glycolytic pathways were down-regulated in response to Rhizopus oryzae, which was associated with an ER-stress response. TLR5 was identified to be uniquely regulated by Aspergillus fumigatus and to control cytokine release in response to this fungus. In conclusion, our data reveals the transcriptional profiles induced by C. albicans, A. fumigatus, and R. oryzae, and describes both the common and specific antifungal host responses that could be exploited for novel therapeutic strategies.

Vitamin D among Patients of Pulmonary and Extrapulmonary Tuberculosis: A Prospective Case-control Study

Background:

Vitamin D has an essential role in enhancing the immune system to fight and destroy bacteria. People with vitamin D deficiency are highly liable to develop active pulmonary and extrapulmonary tuberculosis.

Objective:

: To evaluate the serum level of vitamin D among patients with pulmonary and extrapulmonary tuberculosis.

Patients and Methods:

A case-control prospective study was conducted among patients with pulmonary and extrapulmonary tuberculosis and asymptomatic persons (controls). The study included 80 participants, 50 were TB patients, while 30 were controls. Vitamin D 1, 25(OH) assay was done for all.

Results:

Vitamin D assay of the included subjects revealed that 52 patients were vitamin D deficient, 7 patients had insufficient vitamin D and 21 had normal serum levels. Of the extrapulmonary TB patients, 35 (100%) had vitamin D deficiency, in pulmonary TB patients, 15 (100%) were vitamin D deficient. While 2 study subjects (6.7%) in the control group were deficient of vitamin D, 7 (23.3%) had insufficient vitamin D and 21cases had normal vitamin D levels. There was a statistically significant relationship between pulmonary and extrapulmonary TB cases and vitamin D deficiency (P< 0.001).

Conclusion:

Vitamin D deficiency was found among pulmonary and extrapulmonary tuberculosis patients especially among female patients and patients in rural residence. The current study needs additional work to evaluate the value of adding vitamin D to the TB treatment regimen.

Effects of calcitriol on oxidative burst, phagocytic function, and leukocyte cytokine production in shelter dogs

Background

The active metabolite of vitamin D, calcitriol, has been shown across many different species to augment innate immune responses and dampen aberrant proinflammatory cytokine production. Community acquired infections are common in shelters and consume limited shelter resources, impact adoption rates, and can result in unnecessary euthanasia. Prophylactic oral vitamin D supplementation decreases the incidence and severity of upper and lower respiratory tract infections in humans. Before a clinical trial investigating the clinical benefit of oral vitamin D supplementation in shelter dogs can be pursued, an in vitro study evaluating the immunomodulatory effects of calcitriol in blood from shelter dogs is warranted. Therefore, the objective of this study was to determine if incubation of whole blood obtained from apparently healthy dogs housed in a shelter for ≥7 days with calcitriol would alter granulocyte/monocyte (GM) oxidative burst and phagocytic function as well as pathogen-associated molecular pattern (PAMP)-stimulated leukocyte production of tumor necrosis factor (TNF)-α, and interleukin (IL)-6, and IL-10.

Results

Ten dogs housed in a shelter for ≥7 days were enrolled in a prospective cohort study. Whole blood from these dogs was incubated with calcitriol (10^− 7 M) or diluent (control) for 24 h. Subsequent to this incubation, phagocytosis of opsonized-Escherichia coli (E. coli) and E. coli-induced oxidative burst were evaluated via flow cytometry. In addition, leukocyte production of TNF-α, IL-6, and IL-10 were measured using a canine-specific multiplex bead assay. Calcitriol significantly decreased leukocyte TNF-α production (p = 0.009) and increased IL-10 production (p = 0.002). Tumor necrosis factor-α-to-IL-10 ratio was significantly decreased with calcitriol (p = 0.017), while IL-6 production as well as GM oxidative burst and phagocytic function were not significantly affected.

Conclusions

These data indicate that calcitriol attenuates proinflammatory immune responses without affecting GM oxidative burst or phagocytic function in vitro in whole blood obtained from apparently healthy shelter dogs.

Vitamin D3 modulates yellow catfish (Pelteobagrus fulvidraco) immune function in vivo and in vitro and this involves the vitamin D3/VDR-type I interferon axis

Vitamin D₃ (VD₃) has been shown to regulate immune function in mammals. 1,25-dihydroxyvitamin (1,25(OH)₂D₃) is the active form of vitamin D₃, which is also known as calcitriol. The current study investigated the immunomodulatory effects of 1,25(OH)₂D₃ on the innate immune response of yellow catfish (Pelteobagrus fulvidraco) after in vivo and in vitro immune challenge. The in vivo results showed that increasing dietary vitamin D₃ decreased mortality, enhanced the immune protective rate, and increased serum lysozyme, catalase and SOD activities in yellow catfish infected with Edwardsiella Ictaluri (p < 0.05). The in vitro results showed that 1,25(OH)₂D₃ (0, 1, 10, 100, 200 pM) dose-dependently attenuated the rate of apoptosis and production or reactive oxygen species and increased the phagocytic activity of head kidney macrophages stimulated with 10 mg/L lipopolysaccharide (LPS) and 100 mg/L of Poly(I:C) (p < 0.05). Real-time quantitative PCR results showed that increasing dietary vitamin D₃ content in vivo and increasing the level of 1,25(OH)₂D₃in vitro partially regulated the expression of VD₃/VDR-type I interferon axis genes (vdr, irf-3, ifn-a, jak1, stat1, ifi56 and ifp35) after immune challenge. These results indicated that vitamin D₃ content helped yellow catfish to resist oxidative stress and inflammation caused by immune challenge, and immunomodulation involved the VD₃/VDR-type I interferon action axis.

The current global situation for tuberculous meningitis: epidemiology, diagnostics, treatment and outcomes

Tuberculous meningitis (TBM) results from dissemination of M. tuberculosis to the cerebrospinal fluid (CSF) and meninges. Ischaemia, hydrocephalus and raised intracranial pressure frequently result, leading to extensive brain injury and neurodisability. The global burden of TBM is unclear and it is likely that many cases are undiagnosed, with many treated cases unreported. Untreated, TBM is uniformly fatal, and even if treated, mortality and morbidity are high. Young age and human immunodeficiency virus (HIV) infection are potent risk factors for TBM, while Bacillus Calmette-Guérin (BCG) vaccination is protective, particularly in young children. Diagnosis of TBM usually relies on characteristic clinical symptoms and signs, together with consistent neuroimaging and CSF parameters. The ability to confirm the TBM diagnosis via CSF isolation of M. tuberculosis depends on the type of diagnostic tests available. In most cases, the diagnosis remains unconfirmed. GeneXpert MTB/RIF and the next generation Xpert Ultra offer improved sensitivity and rapid turnaround times, and while roll-out has scaled up, availability remains limited. Many locations rely only on acid fast bacilli smear, which is insensitive. Treatment regimens for TBM are based on evidence for pulmonary tuberculosis treatment, with little consideration to CSF penetration or mode of drug action required. The World Health Organization recommends a 12-month treatment course, although data on which to base this duration is lacking. New treatment regimens and drug dosages are under evaluation, with much higher dosages of rifampicin and the inclusion of fluoroquinolones and linezolid identified as promising innovations. The inclusion of corticosteroids at the start of treatment has been demonstrated to reduce mortality in HIV-negative individuals but whether they are universally beneficial is unclear. Other host-directed therapies show promise but evidence for widespread use is lacking. Finally, the management of TBM within health systems is sub-optimal, with drop-offs at every stage in the care cascade.

Influence of Vitamin D on Islet Autoimmunity and Beta-Cell Function in Type 1 Diabetes

Type 1 diabetes (T1D) is a chronic autoimmune disease leading to immune-mediated destruction of pancreatic beta cells, resulting in the need for insulin therapy. The incidence of T1D is increasing worldwide, thus prompting researchers to investigate novel immunomodulatory strategies to halt autoimmunity and modify disease progression. T1D is considered as a multifactorial disease, in which genetic predisposition and environmental factors interact to promote the triggering of autoimmune responses against beta cells. Over the last decades, it has become clear that vitamin D exerts anti-inflammatory and immunomodulatory effects, apart from its well-established role in the regulation of calcium homeostasis and bone metabolism. Importantly, the global incidence of vitamin D deficiency is also dramatically increasing and epidemiologic evidence suggests an involvement of vitamin D deficiency in T1D pathogenesis. Polymorphisms in genes critical for vitamin D metabolism have also been shown to modulate the risk of T1D. Moreover, several studies have investigated the role of vitamin D (in different doses and formulations) as a potential adjuvant immunomodulatory therapy in patients with new-onset and established T1D. This review aims to present the current knowledge on the immunomodulatory effects of vitamin D and summarize the clinical interventional studies investigating its use for prevention or treatment of T1D.

Opportunities for Overcoming Mycobacterium tuberculosis Drug Resistance: Emerging Mycobacterial Targets and Host-Directed Therapy

The ever-increasing incidence of drug-resistant Mycobacterium tuberculosis infections has invigorated the focus on the discovery and development of novel treatment options. The discovery and investigation of essential mycobacterial targets is of utmost importance. In addition to the discovery of novel targets, focusing on non-lethal pathways and the use of host-directed therapies has gained interest. These adjunctive treatment options could not only lead to increased antibiotic susceptibility of Mycobacterium tuberculosis, but also have the potential to avoid the emergence of drug resistance. Host-directed therapies, on the other hand, can also reduce the associated lung pathology and improve disease outcome. This review will provide an outline of recent opportunities.

Tuberculosis control in India: Refocus on nutrition

Many western societies have eliminated tuberculosis years before the advent of potent anti-tuberculous drugs, as a result of the improved standards of living and good nutrition. But even with the availability of powerful anti-tuberculous drugs, India still has a long road ahead to reach the "End TB by 2025" goal. One of the major reason is that tuberculosis control program in India till now have focused primarily on case detection and medical treatment of active tuberculosis. Drug treatment alone does not completely prevent the occurrence of new infections in the community and also contributes to development of drug resistant strains if used improperly or incompletely. Although the treatment of active cases can reduce the period of transmission of disease, a significant amount of transmission to contacts occurs even before they have been diagnosed and treated. Additionally, this approach cannot prevent re-activation to active TB in the vast pool of persons with latent TB infection. Tuberculosis occurs in those with suppressed cell mediated immunity mainly due to poor nutritional status. Improving the nutritional status of the society by several social interventions hand-in-hand with utilizing the available anti-tuberculous drugs is possibly the only effective strategy. Promising programmatic guidance for nutritional support in TB patients have been formulated by the Central TB division of India but it needs a refocusing of TB control strategies towards nutrition at all levels and strong public health actions for effective implementation.

Effects of calcitriol on phagocytic function, toll-like receptor 4 expression, and cytokine production of canine leukocytes

OBJECTIVE To determine the in vitro effects of calcitriol on indicators of immune system function in blood samples collected from healthy dogs. SAMPLE Blood samples from 8 healthy adult dogs. PROCEDURES Blood samples were incubated with calcitriol (10^-7M) or control substance for 24 hours. Afterward, lipopolysaccharide (LPS)-, lipoteichoic acid (LTA)-, and N-acetylmuramyl-l-alanyl-d-isoglutamine hydrate (MDP)-stimulated leukocyte production of tumor necrosis factor (TNF) and interleukin-10 (IL10) were measured with a canine-specific multiplex assay. Phagocytosis of opsonized Escherichia coli and leukocyte expression of constitutive toll-like receptor 4 (TLR4) were evaluated via flow cytometry. Blood samples from 3 dogs were used to create a concentration-response curve to evaluate whether the observed cytokine modulation was concentration dependent. RESULTS Incubation of canine blood samples with calcitriol resulted in significant decreases in LPS-, LTA-, and MDP-stimulated leukocyte production of TNF but not IL10. Blunting of TNF production was concentration dependent. Leukocyte calcitriol exposure had no significant effect on phagocytosis and TLR4 expression. CONCLUSIONS AND CLINICAL RELEVANCE These data indicated that calcitriol induced an anti-inflammatory shift in canine leukocytes exposed to LPS, LTA, and MDP in vitro, without altering phagocytosis or TLR4 expression. Thus, calcitriol could represent a novel candidate immunomodulatory treatment for dogs.

Calcitriol increases nitric oxide production and modulates microbicidal capacity against Mycobacterium bovis in bovine macrophages

Bovine tuberculosis, a re-emerging infectious disease caused by Mycobacterium bovis, can be transmitted to humans. Global prevalence of M. bovis in humans is underestimated and represents a serious public health risk in developing countries. In light of this situation, it is important to note that our understanding of the immunopathogenesis of human tuberculosis can be improved by studying this disease in the bovine model. Stimulation of the bovine innate immune system with calcitriol (1,25(OH)2D3) leads to an increase in bactericidal molecules involved in macrophage antimicrobial activity. It is unknown, however, if calcitriol´s effect on bovine macrophages impacts intracellular bacterial replication. With these considerations in mind, this study sought to investigate the specific role of calcitriol in tuberculosis control in bovine macrophages, in the hopes of uncovering information applicable to human tuberculosis. As such, infection with M. bovis was shown to induce expression of CYP27B1 and VDR genes in macrophages. Moreover, addition of 1,25(OH)2D3 to cultures of macrophages previously infected with mycobacteria and/or activated by LPS triggered cellular expression of nitric oxide synthase (NOS2) and increased nitrite concentrations, both indicators of nitric oxide (NO) production. By means of a microbicidal assay, addition of 1,25(OH)2D3 was seen to increase macrophage phagocytosis and to decrease mycobacterial intracellular replication. Thus, taken together, our results show that calcitriol can help stimulate the innate immune system of bovines by increasing phagocytosis and decreasing intracellular replication of microorganisms, such as M. bovis, in macrophages, through the VDR pathway.

1, 25-dihydroxyvitamin D3 downregulates cytotoxic effector response in pulmonary tuberculosis

1,25-dihydroxyvitaminD₃ [1,25(OH)₂D₃] modulates both the innate and adaptive immunity in tuberculosis. We explored the effect of 1,25(OH)₂D₃ on cytolytic molecules like perforin, granulysin, and granzyme-B in T-cells and natural killer cells during M. tuberculosis (Mtb) infection. Peripheral blood mononuclear cells (PBMCs) from 45 healthy controls (HCs) and 45 pulmonary tuberculosis (PTB) patients were cultured with Mtb in the absence or presence of 1,25(OH)₂D₃ for 72 h. The percentage of perforin, granulysin, and granzyme-B positive cells were estimated by flow cytometry. 1,25(OH)₂D₃ significantly decreased the percentage of cytolytic molecules in total, CD4+, CD8+ and CD56+ cells in HCs and PTB patients (p < 0.05). Moreover, 1,25(OH)₂D₃ downregulates IFN-γ levels while upregulate the anti-inflammatory cytokine IL-10. Correlation revealed that the total percentage of cytolytic molecules were positively correlated with IFN-γ level, whereas negatively correlated with IL-10 level in both the study subjects (p < 0.05). This results suggests that 1,25(OH)₂D₃ downregulate the expression of cytolytic molecues and act as anti-inflammatory in adaptive immune response, which might help to reduce inflammation and tissue damage during the active stage of the disease.

Effect of calcitriol on in vitro whole blood cytokine production in critically ill dogs

Hypovitaminosis D has been identified as a predictor of mortality in human beings, dogs, cats and foals. However, the immunomodulatory effects of vitamin D in critically ill dogs has not been evaluated. The aim of this study was to evaluate the effect of calcitriol on cytokine production from whole blood collected from critically ill dogs in vitro. Twelve critically ill dogs admitted to a veterinary intensive care unit (ICU) were enrolled in a prospective cohort study. Whole blood from these dogs was incubated with calcitriol (2×10^-7M) or ethanol (control) for 24h. Subsequent to this incubation, lipopolysaccharide (LPS)-stimulated whole blood production of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-10 were measured using a canine-specific multiplex assay. Calcitriol significantly increased LPS-stimulated whole blood production of IL-10 and decreased TNF-α production without significantly altering IL-6 production. There was no significant difference in whole blood cytokine production capacity between survivors and non-survivors at the time of discharge from the ICU or 30days after discharge. These data suggests that calcitriol induces an anti-inflammatory phenotype in vitro in whole blood from critically ill dogs.

Serum vitamin D concentrations in hospitalized critically ill dogs

Hypovitaminosis D has been extensively documented in critically ill humans. However, whether or not critically ill dogs have alterations in vitamin D concentrations remains unconfirmed. The primary aims of our study were to compare serum 25-hydroxycholecalciferol [25(OH)D] concentrations in critically ill dogs with healthy control dogs, determine the prognostic utility of serum 25(OH)D concentration as a biomarker in critically ill dogs, and to assess if serum 25(OH)D concentrations in critically ill dogs are associated with length of stay in the intensive care unit or illness severity. Serum concentrations of 25(OH)D together with a range of other clinical, biochemical, and hematological parameters, were measured in 99 dogs within 24 hours of admission to the Intensive Care Unit (ICU). Critically ill dogs (P = 0.001) and dogs with sepsis (P = 0.002) had significantly lower serum 25(OH)D concentrations compared to healthy control dogs. In addition, serum 25(OH)D concentration was an independent predictor of in-hospital and 30 day survival. Using a cut-off of 33 ng/mL, serum 25(OH)D concentrations had excellent sensitivity (0.94; 95% CI, 0.71–1.00), but poor specificity (0.41; 95% CI, 0.31–0.53) for detection of survival. Serum 25(OH)D concentrations were inversely associated with acute patient physiologic and laboratory evaluation (APPLE) fast score but were not associated with ICU length of stay. Hospitalized dogs with critical illness have decreased serum 25(OH)D concentrations compared to healthy dogs and can be used to predict survival in this cohort.

Smaller long bone cross-sectional size in people who died of tuberculosis: Insights on frailty factors from a 19th and early 20th century Finnish population

There is little research on how individuals suffering from tuberculosis may differ from those not infected in terms of overall skeletal morphology. Tuberculosis was endemic in 19th and early 20th century Finland making documented skeletal collections of Finns ideal to study effects of the disease on bone. The present study compares long bone cross-sectional total area between individuals who died of tuberculosis and those with another recorded cause of death in a Finnish sample. Adult male individuals (N = 105) were selected for analysis. Complete humeri (N = 56), femora (N = 66) and tibiae (N = 64) were 3D scanned using a laser scanner and total cross-sectional areas calculated with AsciiSection software. Individuals who died of tuberculosis (N = 24, 15 humeri, 14 femora, 13 tibiae) had, when standardized for body size, significantly smaller total cross-sectional femoral and humeral, but not tibial, areas. The mechanisms behind the observed relationship may reflect a combination of biological 'frailty' in terms of susceptibility to infection, reduced childhood activity and/or vitamin D deficiency, which possibly influenced both subperiosteal development during adolescence and, later, susceptibility to contracting and dying of TB. Due to the relatively small sample future studies are needed to further investigate the relationship between TB and bone cross-sectional size.

Malnutrition: Modulator of Immune Responses in Tuberculosis

Nutrition plays a major role in the management of both acute and chronic diseases, in terms of body’s response to the pathogenic organism. An array of nutrients like macro- and micro-nutrients, vitamins, etc., are associated with boosting the host’s immune responses against intracellular pathogens including mycobacterium tuberculosis (M.tb). These nutrients have an immunomodulatory effects in controlling the infection and inflammation process and nutritional deficiency of any form, i.e., malnutrition may lead to nutritionally acquired immunodeficiency syndrome, which greatly increases an individual’s susceptibility to progression of infection to disease. This narrative review looks at the various mechanisms by which nutrition or its deficiency leads to impaired cell mediated and humoral immune responses, which in turn affects the ability of an individual to fight M.tb infection or disease. There is very little evidence in the literature that any specific food on its own or a specific quantity can alter the course of TB disease or be effective in the treatment of malnutrition. Further clinical trials or studies will be needed to recommend and to better understand the link between malnutrition, tuberculosis, and impaired immunity.

Host-Directed Therapeutic Strategies for Tuberculosis

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains a leading cause of morbidity and mortality in humans worldwide. Currently, the standard treatment for TB involves multiple antibiotics administered for at least 6 months. Although multiple antibiotics therapy is necessary to prevent the development of drug resistance, the prolonged duration of treatment, combined with toxicity of drugs, contributes to patient non-compliance that can leads to the development of drug-resistant Mtb (MDR and XDR) strains. The existence of comorbid conditions, including HIV infection, not only complicates TB treatment but also elevates the mortality rate of patients. These facts underscore the need for the development of new and/or improved TB treatment strategies. Host-directed therapy (HDT) is a new and emerging concept in the treatment of TB, where host response is modulated by treatment with small molecules, with or without adjunct antibiotics, to achieve better control of TB. Unlike antibiotics, HDT drugs act by directly modulating host cell functions; therefore, development of drug resistance by infecting Mtb is avoided. Thus, HDT is a promising treatment strategy for the management of MDR- and XDR-TB cases as well as for patients with existing chronic, comorbid conditions such as HIV infection or diabetes. Functionally, HDT drugs fine-tune the antimicrobial activities of host immune cells and limit inflammation and tissue damage associated with TB. However, current knowledge and clinical evidence is insufficient to implement HDT molecules as a stand-alone, without adjunct antibiotics, therapeutic modality to treat any form of TB in humans. In this review, we discuss the recent findings on small molecule HDT agents that target autophagy, vitamin D pathway, and anti-inflammatory response as adjunctive agents along with standard antibiotics for TB therapy. Data from recent publications show that this approach has the potential to improve clinical outcome and can help to reduce treatment duration. Thus, HDT can contribute to global TB control programs by potentially increasing the efficiency of anti-TB treatment.

Low serum vitamin D levels in type 2 diabetes patients are associated with decreased mycobacterial activity

Background

Concurrent diabetes mellitus and tuberculosis represent a significant health problem worldwide. Patients with diabetes mellitus have a high risk of tuberculosis, which may be mediated by an abnormal innate immune response due to hyperglycaemia or low vitamin D levels.

Methods

In the present study, we evaluated inactive vitamin D serum levels and the monocyte response to infection with M. tuberculosis, including phagocytosis of M. tuberculosis, antimycobacterial activity, LL-37, human β defensin-2 and IL-10 gene expression and nitric oxide production, between type 2 diabetes mellitus patients (n = 51) and healthy volunteers (n = 38).

Results

Twenty-seven type 2 diabetes mellitus patients had inadequate inactive vitamin D levels (<50 nM). The percentages of M. tuberculosis phagocytosis between monocytes were similar across groups according to microscopy. Intracellular mycobacterial growth was similar in infected monocytes from both groups. However, M. tuberculosis growth was significantly higher in monocytes obtained from type 2 diabetes mellitus patients and lower vitamin D levels after 1-h (D0) and 72-h (D3) post-infection (p ≤ 0.05). LL-37, human β defensin-2 and IL-10 mRNA expression were similar between monocytes across groups; vitamin D serum levels and LL-37, human β defensin-2 and IL-10 expression were not correlated. Nitric oxide production was significantly higher in healthy volunteers than in type 2 diabetes mellitus patients with low vitamin D serum levels at D3 post-infection (p ≤ 0.05).

Conclusions

Our results show that monocytes from type 2 diabetes mellitus patients and low vitamin D serum levels show an impaired ability to control the intracellular growth of M. tuberculosis, which is not associated with significant decrease of LL-37 or human β defensin-2 expression. Vitamin D could be the link between diabetes and tuberculosis susceptibility.

Electronic supplementary material

The online version of this article (10.1186/s12879-017-2705-1) contains supplementary material, which is available to authorized users.

Influence of Cdx2 and TaqI Gene Variants on Vitamin D3 Modulated Intracellular Chemokine Positive T-Cell Subsets in Pulmonary Tuberculosis

PURPOSE

We studied the effect of 1,25(OH)₂D₃ (vitamin D₃) on intracellular chemokine-positive T-cell subsets in whole blood cultures of healthy controls and patients with pulmonary tuberculosis.

METHODS

Genotyping was performed by the polymerase chain reaction-restriction fragment length polymorphism method. The regulatory role of the Cdx2 and 3'UTR TaqI gene variants on chemokine-positive T-cell subsets was studied from culture filtrate antigen stimulated with or without vitamin D₃ treated whole blood cultures of 60 healthy controls and 50 patients with pulmonary tuberculosis.

FINDINGS

Vitamin D₃ significantly suppressed monocyte chemoattractant protein 1, macrophage inhibitory protein (MIP)-1α, MIP-1β, regulated on activation, normal T-cell expressed and secreted (RANTES), and interferon-γ inducible protein 10 (IP-10)-positive T-cell subsets compared with culture filtrate antigen stimulated cells without vitamin D₃ treatment. In the Cdx2 AA genotype, vitamin D₃ decreased MIP-1α, MIP-1β, and RANTES-positive T cells compared with the GG genotype. Whereas in the TaqI tt genotype, decreased MIP-1β and RANTES and increased IP-10-positive T cells were observed compared with the TT genotype in vitamin D₃ treated cells (p < 0.05).

IMPLICATIONS

This study suggests that vitamin D₃ may regulate the chemokine-positive T cells through the Cdx2 AA and TaqI tt genotypes. This could be helpful to regulate chemokine-mediated inflammatory response during active disease condition. Hence, vitamin D₃ supplementation along with tuberculosis drugs may be useful for faster recovery from the disease.

Vitamin D both facilitates and attenuates the cellular response to lipopolysaccharide

Vitamin D has a range of non-skeletal health effects and has been implicated in the response to respiratory infections. The aim of this study was to assess the effect of vitamin D on the response of epithelial cells, neutrophils and macrophages to lipopolysaccharide (LPS) stimulation. BEAS-2B cells (airway epithelial cell line) and primary neutrophils and macrophages isolated from blood samples were cultured and exposed to LPS with and without vitamin D (1,25(OH)₂D). The production of IL-6, IL-8, IL-1β and TNF-α of all cells and the phagocytic capacity of neutrophils and macrophages to E. coli were assessed. Vitamin D had no effect on BEAS-2B cells but enhanced the production of IL-8 in neutrophils (p = 0.007) and IL-1β in macrophages (p = 0.007) in response to LPS. Both vitamin D (p = 0.019) and LPS (p < 0.001) reduced the phagocytic capacity of macrophages. These data suggest that the impact of vitamin D on responses to infection are complex and that the net effect will depend on the cells that respond, the key response that is necessary for resolution of infection (cytokine production or phagocytosis) and whether there is pre-existing inflammation.

Regulatory role of CCL5 (rs2280789) and CXCL10 (rs56061981) gene polymorphisms on intracellular CCL5 and CXCL10 expression in pulmonary tuberculosis

Genetic variations in chemokine genes influence the chemoattractive properties of T cells which may be associated with outcome of infections. In present study, we have investigated the regulatory role played by In1.1T/C (rs2280789) polymorphism of CCL5 and -135G/A (rs56061981) polymorphism of CXCL10 gene on intracellular CCL5 and CXCL10 expression in T cells. Whole blood cell cultures were stimulated with culture filtrate antigen (CFA) and infected with live M. tuberculosis were used for intracellular CCL5 and CXCL10 expression using flow cytometry. Genotyping was performed using polymerase chain reaction based restriction fragment length polymorphism (PCR-RFLP). Significantly higher expression of CCL5 expressing CD3+ and CD3+ CD8+ T cells were observed in HCs with In1.1TT genotype compared to C allele carrier (TT+TC) under unstimulated and CFA induced cultures (p<0.05). In -135G/A (rs56061981) polymorphism, PTB patients with GG genotype showed a significantly decreased expression of CD3+ CXCL10+ and CD3+ CD4+ CXCL10+ T cells compared to A allele carrier (GA+AA) under unstimulated, CFA induced and M. tuberculosis infected cultures (P<0.05). The present study suggest that TT genotype of CCL5 In1.1T/C (rs2280789) polymorphism play an important role to increased CCL5 expression in T cell which may enhanced Th1 immunity and help in protection against tuberculosis. The study also suggests GG genotype of CXCL10 -135G/A (rs56061981) polymorphism decreased CXCL10 expression in T cells which may have defective recruitment of mononuclear cells at the site of infection as well granuloma formation and in turn contribute to progression of TB.

Effect of 1,25-dihydroxyvitamin D3 on the expression of mannose receptor, DC-SIGN and autophagy genes in pulmonary tuberculosis

1,25-dihydroxyvitamin D3 [1,25(OH)2D3] is a powerful immuno-modulator, which enhances expression of antimicrobial peptides and induces autophagy in monocytes/macrophages. Since 1,25(OH)2D3 increases the phagocytic potential of monocytes/macrophages, we have explored the effect of 1,25(OH)2D3 on the expression of receptors such as mannose receptor (CD206) and DC-SIGN (CD209) as well as autophagy genes such as ATG5 and Beclin-1 (BECN1) in monocytes/macrophages of healthy controls (HCs) and pulmonary tuberculosis (PTB) patients with and without cavitary disease. Peripheral blood mononuclear cells (PBMCs) were isolated from 40 HCs and 40 PTB patients and were cultured for 72 h with Mtb in the presence or absence of 1,25(OH)2D3 at 10(-7) M concentration. 1,25(OH)2D3 significantly upregulated the expression of mannose receptor, ATG5 and BECN1; whereas DC-SIGN expression was suppressed in Mtb infected cells of both study groups (p < 0.05). The 1,25(OH)2D3-induced expression of CD206, ATG5 and BECN1 genes was lower in PTB patients compared to HCs, whereas expression of these genes was impaired in PTB patients with cavitary disease. Moreover, the relative expression of ATG5 and BECN1 was positively correlated with monocyte/macrophage phagocytosis and cathelicidin antimicrobial peptide gene expression in HCs and PTB patients (p < 0.05). Our study results suggest that vitamin D supplementation in PTB patients without cavitary disease could enhance innate immune functions and may help to control intracellular growth of mycobacteria in macrophages.

25-Hydroxy Vitamin D, Vitamin D Receptor and Toll-like Receptor 2 Polymorphisms in Spinal Tuberculosis: A Case-Control Study

Vitamin D deficiency and vitamin D receptor (VDR) gene abnormalities confer susceptibility to tuberculosis. Toll-like receptors (TLRs), such asTLR-2, are also important mediators of inflammatory response against Mycobacterium tuberculosis. We evaluated serum vitamin D, and VDR and TLR-2 gene polymorphisms in patients with spinal tuberculosis.This study comprised of 3 groups: spinal tuberculosis, pulmonary tuberculosis, and controls (each with 106 subjects). Enzyme-linked immunosorbent assay was used to measure vitamin D levels, and polymerase chain reaction-sequencing method was used to analyze VDR and TLR-2 gene polymorphisms. Patients were followed up for 6 months.Vitamin D deficiency was significantly more prevalent in patients with spinal tuberculosis (P < 0.001) and pulmonary tuberculosis (P = 0.011), versus controls. The heterozygous and mutant genotypes of VDR TaqI gene were significantly associated with spinal tuberculosis (P < 0.001; odds ratio [OR] 4.74 [2.45-9.18]) and pulmonary tuberculosis (P < 0.001; OR 3.52 [1.80-6.88]) when compared with controls. The heterozygous and mutant variants of VDR ApaI gene were significantly more common in patients with spinal tuberculosis in comparison with patients with pulmonary tuberculosis (P < 0.001; OR 2.90 [1.65-5.10]) and controls (P < 0.001; OR 6.56 [3.41-12.61]). We did not observe any significantly different results for TLR-2 gene polymorphisms. Vitamin D deficiency, VDR, and TLR-2 polymorphisms did not affect the 6-month disability.Vitamin D deficiency and VDR gene polymorphisms are significantly more prevalent in people with pulmonary and spinal tuberculosis. They may, in isolation or collectively, confer susceptibility to pulmonary and spinal tuberculosis.

Vitamin D3 enhances bactericidal activity of macrophage against Pseudomonas aeruginosa

BACKGROUND

The bioactive form of vitamin D3, i.e.1,25-dihydroxyvitamin D3 (1,25(OH)2D3) vitamin D has been shown to modulate monocytes/macrophages physiology and its response against bacterial infections. Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic bacterial pathogen that can most frequently be fatal in immunocompromised infected people.

METHODS

We investigated the ex vivo effect of 1,25(OH)2D3 on monocyte-derived macrophages function against P. aeruginosa infection.

RESULTS

Relative vitamin D receptor (VDR) mRNA expression was significantly increased in infected and 1,25(OH)2D3-treated macrophages compared to controls (p<0.01). Treatment with 1,25(OH)2D3 markedly resulted in up-regulation of nitric oxide (NO) and IL-1β production and down-regulation of IL-10 levels (respectively, p=0.029, p=0.048 and p=0.008). Additionally, 1,25(OH)2D3 significantly increased M1/M2 macrophage ratio (p<0.05) and slightly reduced intracellular bacterial development. Furthermore, the arginase activity, P. aeruginosa phagocytosis and killing were significantly increased in cells that were both infected and 1,25(OH)2D3-treated compared to the infected, but not 1,25(OH)2D3-treated macrophages (respectively, p<0.001, p<0.01 and p<0.001).

CONCLUSIONS

We show in this study that bioactive from of vitamin D [1,25-dihydroxyvitamin D3 (1,25D3)] can enhance M1 macrophage polarization and their bactericidal protective activity against P. aeruginosa. Future works would involve improving the treatment response through dose-dependent effect studies, both in ex vivo and in vivo models.

Effect of 1,25-dihydroxy vitamin D3 on cathelicidin expression in patients with and without cavitary tuberculosis

1,25-dihydroxy vitamin D3 (1,25(OH)2D3) is a potent immuno-modulator which induces LL-37, the active peptide of cathelicidin, and restricts the growth of Mycobacterium tuberculosis (Mtb) in human macrophages. In the present study, we investigated the effect of 1,25(OH)2D3 on cathelicidin antimicrobial peptide (CAMP) expression in healthy controls (HCs) and pulmonary tuberculosis (PTB) patients. Peripheral blood mononuclear cells (PBMCs) from 50 HCs and 35 PTB patients were cultured for 72 h either with Mtb alone or Mtb with 1,25(OH)2D3 at 10(-7) M concentration. 1,25(OH)2D3 significantly up regulated the macrophage phagocytosis, CD14, CAMP gene expression and hCAP18 protein in HCs and PTB patients (p < 0.05). A significant positive correlation was observed between macrophage phagocytosis and CAMP gene expression in both the study groups (p < 0.05). Moreover, 1,25(OH)2D3 up regulated CAMP gene expression was more prominent in PTB patients without lung cavity (less severe form of disease) as compared to patients with cavitary TB (severe form of disease) (p < 0.05). The present study suggests that vitamin D may be used as an adjunct to anti-TB treatment and may be useful for a quicker recovery from less severe forms of TB disease.

Vitamin D: Immuno-modulation and tuberculosis treatment

Tuberculosis (TB) is a major global health problem and often coincides with vitamin D deficiency. High doses of vitamin D were widely used to treat TB during the pre-antibiotic era. Vitamin D exerts its action through vitamin D receptor (VDR), and VDR gene polymorphisms are associated with susceptibility or resistance to tuberculosis as well as sputum smear and culture conversion during anti-TB treatment. In-vitro studies have revealed that 1,25-dihydroxyvitamin D3 enhances innate immunity by increased expression of various antimicrobial peptides, including cathelicidin, and induction of autophagy of the infected cells thus restricts the intracellular growth of Mycobacterium tuberculosis in macrophages. On the other hand, vitamin D has been shown to suppress the pro-inflammatory cytokine response and enhance the anti-inflammatory response. Supplementation with vitamin D in concert with treatment for TB may be beneficial with respect to minimizing the excessive tissue damage that occurs during the active stage of tuberculosis disease. Several clinical trials have evaluated vitamin D supplementation as an adjunct therapy in the treatment for tuberculosis. However, results are conflicting, owing to variations in dose regimens and outcomes. Further investigations are needed to find the optimal concentration of vitamin D for supplementation with standard anti-TB drugs to optimize treatment, which could help to effectively manage both drug-sensitive and drug-resistant tuberculosis.

Vitamin D and its effects on glucose homeostasis, cardiovascular function and immune function

In recent years there has been increasing interest in the non-skeletal effects of vitamin D. It has been suggested that vitamin D deficiency may influence the development of diabetes, cardiovascular dysfunction and autoimmune diseases. This review focuses on the current knowledge of the effects of vitamin D and its deficiency on cardiovascular function, glucose homeostasis and immune function, with a particular focus on children. Although, there is good evidence to show that there is an association between vitamin D deficiency and an abnormality of the above systems, there is little evidence to show that vitamin D supplementation leads to an improvement in function, especially in childhood.

1,25-Dihydroxy vitamin D3 downregulates pro-inflammatory cytokine response in pulmonary tuberculosis

1,25-Dihydroxy vitamin D3 [1,25(OH)2D3] is a potent immunomodulator and regulates various immune responses to Mycobacterium tuberculosis (Mtb). The present study aimed to understand the effect of 1,25(OH)2D3 on pro-inflammatory cytokine response to Mtb antigen. Peripheral blood mononuclear cells from 42 healthy controls (HCs) and 42 pulmonary tuberculosis (PTB) patients were cultured with culture filtrate antigen (CFA) of Mtb with and without 1,25(OH)2D3 at 10(-7)M concentration for 72 h. The levels of IL-1α, IL-1β, TNF-α, TNF-β, IL-17 and IL-23 were estimated in the culture supernatants by ELISA. 1,25(OH)2D3 significantly suppressed all the CFA induced pro-inflammatory cytokines (p<0.05) studied except IL-1β in both HCs and PTB patients. Among the PTB patients, the observed suppression was visible both in patients with and without cavitary tuberculosis. The present study results suggest that 1,25(OH)2D3 downregulates the production of pro-inflammatory cytokines and may control the exacerbated inflammatory response that may protect the host from excessive tissue damage at the site of infection.

Miliary tuberculosis with atypical presentation in an immunocompetent young African man

We present an atypical case of tuberculosis in an immunocompetent man from west Africa living in Europe. The patient entered the hospital with a painful lump of 3 cm on his right clavicule which he noticed 2 weeks before and back pain. During the examinations for further evaluation his condition deteriorated within short time. Tuberculosis was diagnosed, treatment started but he needed mechanical ventilation at the intensive care unit and had kidney failure. The further evolvement was favourable in the end but needed intensive treatment for over 4 weeks. Tuberculosis cases with such severe evolution are rather known with immunodeficient patients. Extrapulmonary tuberculosis, especially skeletal tuberculosis is seen more frequent in young immunocompetent migrants. The migrating persons seem to be more at risk to get sick than the ones staying in their origin country. We suppose the course of our patient's disease is miliary or septic, of which both are rather rare entities.

Characterization of polarized THP-1 macrophages and polarizing ability of LPS and food compounds

Little is known about the polarizing potential of currently used human macrophage cell lines, while a better understanding phenomena can support the prediction of effects in vivo based on in vitro analysis. To test the polarization capability of PMA differentiated-THP-1 macrophages (M0), cells were stimulated with 20 ng ml(-1) IFNγ + 1 μg ml(-1) LPS and 20 ng ml(-1) IL-4, which are known to influence macrophage polarization in vivo and ex vivo into the M1 and M2 state, respectively. Apart from several well-known M1 and M2 markers, also new possible markers for M1 and M2 polarization were analysed in this study. The expression of M1 marker genes was up-regulated in IFNγ + LPS stimulated-M0 THP-1 macrophages. The IL-4 stimulated-M0 THP-1 macrophages expressed M2 cell membrane receptor genes. However, M2 chemokine and their receptor genes were only slightly up-regulated which might be due to the complexity of the secondary cell-cell interaction of the chemokine system. Lipopolysaccharides from E. coli (LPS) and food compounds [lentinan, vitamin D3 (vD3) and the combination of lentinan + vitamin D3 (Len + vD3)] were investigated for their polarizing ability on M0 THP-1 macrophages towards either the M1 or M2 state. LPS (700 ng ml(-1)) was able to skew M0 THP-1 macrophages towards the M1 direction since all analysed M1 marker genes were strongly expressed. Lentinan, vD3 and Len + vD3 did not induce expression of either M1 or M2 markers, indicating no polarizing ability of these compounds. Based on the expression of M1 and M2 marker genes we concluded that THP-1 macrophages could be successfully polarized into either the M1 or M2 state. Therefore, they can be used as a new macrophage polarizing model to estimate the polarizing/switching ability of test food compounds.

Vitamin D insufficiency may impair CD4 recovery among Women's Interagency HIV Study participants with advanced disease on HAART

BACKGROUND

Recent studies in HIV-infected men report an association between low vitamin D (25OH-D) and CD4 recovery on HAART. We sought to test this relationship in the Women's Interagency HIV Study (WIHS).

METHODS

We examined 204 HIV-infected women with advanced disease, who started HAART after enrollment in the WIHS. We measured vitamin D (25OH-D) levels about 6 months prior to HAART initiation. The relationship between CD4 recovery (defined as increases of ≥50, 100, and 200 cells at 6, 12, and 24 months) and exposure variables was examined using logistic regression models at 6, 12 and 24 months post-HAART initiation in unadjusted and adjusted analyses, and using multivariable longitudinal Generalized Estimating Equations (GEE). Vitamin D insufficiency was defined as 25OH-D levels at least 30 ng/ml.

RESULTS

The majority were non-Hispanic black (60%) and had insufficient vitamin D levels (89%). In adjusted analyses, at 24 months after HAART, insufficient vitamin D level (OR 0.20, 95% CI 0.05-0.83) was associated with decreased odds of CD4 recovery. The undetectable viral load (OR 11.38, 95% CI 4.31-30.05) was associated with CD4 recovery. The multivariable GEE model found that average immune reconstitution attenuated significantly (P < 0.01) over time among those with insufficient vitamin D levels compared with those with sufficient vitamin D levels.

CONCLUSION

Vitamin D insufficiency is associated with diminished late CD4 recovery after HAART initiation among US women living with advanced HIV. The mechanism of this association on late CD4 recovery may be late vitamin D-associated production of naive CD4 cells during immune reconstitution.

Vitamin D deficiency and changes in serum vitamin D levels with treatment among tuberculosis patients in South Korea

BACKGROUND AND OBJECTIVE

Vitamin D deficiency has been reported to be associated with the development of active tuberculosis (TB), but many discrepancies exist among studies. The aims of this study were to compare the frequency of vitamin D deficiency in a Korean population of TB patients and control subjects, and to monitor the changes in vitamin D levels during TB treatment.

METHODS

Patients with newly diagnosed TB were prospectively enrolled. In addition, healthy volunteers or patients with diseases other than TB were enrolled as controls. Baseline serum 25-hydroxyvitamin D (25-OHD) levels were measured in both groups and compared. In the TB patients, measurements of serum 25-OHD were repeated 1 month after the initiation of treatment and again after completion of treatment.

RESULTS

In total, 116 patients with TB and 86 control subjects were recruited. The median 25-OHD concentration was not different in TB patients at diagnosis (13.9 ng/mL; interquartile range (IQR) 8.80-21.8) compared with control subjects (13.2 ng/mL; IQR 9.6-19.3) (P = 0.97). The frequency of vitamin D deficiency (≤ 10 ng/mL) was also not different in TB patients (36.2%) compared with controls (27.3%) (P = 0.21). In TB patients, the median 25-OHD concentration decreased significantly during treatment, to 12.5 ng/mL at 1 month and 11.0 ng/mL on completion of treatment (P = 0.01).

CONCLUSIONS

Vitamin D levels do not appear to be associated with the development of TB in the Korean population. The median 25-OHD concentration decreased after treatment for TB.

Effect of vitamin D3 on chemokine expression in pulmonary tuberculosis

1,25 Dihydroxy vitamin D(3) (vitamin D(3)) is an immunomodulator and its deficiency has been associated with susceptibility to tuberculosis. We have studied the immunoregulatory role of vitamin D(3) on various chemokine expression in pulmonary tuberculosis. Peripheral blood mononuclear cells obtained from 21 pulmonary tuberculosis (PTB) patients and 24 healthy controls (HCs) were cultured for 48 h with culture filtrate antigen (CFA) of Mycobacterium tuberculosis with or without vitamin D(3) at a concentration 1 × 10(-7)M. The relative mRNA expression of monocyte chemoattractant protein-1 (MCP-1, CCL2), macrophage inflammatory protein-1α (MIP-1α, CCL3), macrophage inflammatory protein-1β (MIP-1β, CCL4), and regulated upon-activation, normal T cell-expressed and secreted (RANTES, CCL5) and IFN-γ inducible protein-10 (IP-10, CXCL10) chemokines were estimated from 48 h old macrophages using real-time polymerase chain reaction (RT-PCR). The culture supernatants were used to estimate the various chemokines including monokine induced by IFN-γ (MIG, CXCL9) levels using cytometric bead array. In HCs, vitamin D(3) significantly suppressed the MCP-1 mRNA expression of CFA stimulated cells (p=0.0027), while no such effect was observed in PTB patients. Vitamin D(3) showed no significant effect on MIP-1α, MIP-1β and RANTES in both the study groups. The CFA induced IP-10 mRNA and protein expression was significantly suppressed by vitamin D(3) in both the study groups (p<0.05). A similar suppressive effect of vitamin D(3) was observed with MIG protein in healthy controls (p=0.0029) and a trend towards a suppression was observed in PTB patients. The suppressive effect of vitamin D(3) is more prominent in CXC chemokines rather than CC chemokines. This suggests that vitamin D(3) may down regulate the recruitment and activation of T-cells through CXC chemokines at the site of infection and may act as a potential anti-inflammatory agent.

Vitamin D rejuvenates aging eyes by reducing inflammation, clearing amyloid beta and improving visual function

Vitamin D(3) plays a key role in immune regulation and may protect against the aging process. A focal point for age-related changes is the outer retina of the eye where there is high metabolic demand resulting in a gradual increase in extracellular deposition, inflammation, and cell loss giving rise to visual decline. Here, we demonstrate that vitamin D(3) administration for only 6 weeks in aged mice significantly impacts on this aging process. Treated mice showed significant reductions in retinal inflammation and levels of amyloid beta (Aβ) accumulation, which is a hallmark of aging. They also had significant reductions in retinal macrophage numbers and marked shifts in their morphology. These changes were reflected in a significant improvement in visual function, revealing that vitamin D(3) is a route to avoiding the pace of age-related visual decline. Excess amyloid beta deposition and inflammation are risk factors leading to age-related macular degeneration (AMD), the largest cause of blindness in those older than 50 years in developed countries. Recently, vitamin D(3) has been linked epidemiologically to protection against age-related macular degeneration. Hence, vitamin D(3) enrichment is likely to represent a beneficial route for those at risk.

Shoulder pain and dysphagia with an unexpected cause

A 31-year-old female pharmacist of Nigerian origin, now resident in London, described 4 months of worsening left-sided subscapular pain despite the use of increasingly potent analgesia. She also described progressive dysphagia, first to solids and later to liquid foods. She remained systemically well, with no associated symptoms and normal physiological observations. In light of raised plasma inflammatory markers and chest radiography demonstrating a widened paraspinal stripe, the patient underwent CT and subsequent MRI of the thorax and upper spine. This revealed bony destruction of multiple higher thoracic vertebrae, with an associated epidural abscess mediating spinal cord impingement at T5. A large prevertebral collection spanning C7-T9 directly compressing and displacing the oesophagus was demonstrated. These findings collectively suggested spinal tuberculosis (Pott's disease); PCR confirmed the presence of Mycobacterium tuberculosis. The patient was successfully treated with oral anti-tuberculous chemotherapy and physiotherapy.

Effect of 1, 25 dihydroxyvitamin D(3) on matrix metalloproteinases MMP-7, MMP-9 and the inhibitor TIMP-1 in pulmonary tuberculosis

Matrix metalloproteinases (MMPs) play a vital role in the pathogenesis of several inflammatory diseases including tuberculosis through tissue remodeling. 1, 25(OH)(2)D(3) has several well recognized biological functions including suppression of MMP production. The influence of 1, 25(OH)(2)D(3) on MMP-7, MMP-9 and tissue inhibitor of metalloproteinase-1 (TIMP-1), production was studied in 43 pulmonary tuberculosis (PTB) patients and 44 healthy controls (HC). Peripheral blood mononuclear cells (PBMCs) were cultured with culture filtrate antigen (CFA) of Mycobacterium tuberculosis (MTB) and live MTB with or without 1, 25(OH)(2)D(3) (10(-7) M) for 48 h and the culture supernatants were assayed for MMP-7, MMP-9, TIMP-1 and cytokines IFN-gamma and TNF-alpha using ELISA. In HC and PTB, the levels of MMP-7, MMP-9 and TIMP-1 were not altered by CFA and live MTB stimulation in both groups. However, a significant decrease in the spontaneous production of MMP-7 (p=0.007), and an increase in MMP-9 (p=0.07) and TIMP-1 (p=0.0001) were observed in PTB patients as compared to HC. Vitamin D(3) significantly reduced the MMP-7 (p=0.0001) and MMP-9 (p=0.0001) and increased the TIMP-1 (p=0.005) level in antigen stimulated and unstimulated cultures of PTB as compared to HC. A significant positive correlation between MMP-9 and IFN-gamma was observed in unstimulated cultures of both HC (p=0.05) and PTB patients (p=0.0007). The present study suggests that 1, 25(OH)(2)D(3) suppresses the production of MMPs and enhances the level of TIMP-1 in tuberculosis. The present study suggests that 1, 25(OH)(2)D(3) may probably play an important role in the pathological process in tuberculosis by downregulating the levels of MMPs and upregulating the levels of TIMPs.

Regulation of vitamin D homeostasis: implications for the immune system

Vitamin D homeostasis in the immune system is the focus of this review. The production of both the activating (25- and 1alpha-hydroxylase) and the metabolizing (24-hydroxylase) enzymes by cells of the immune system itself, indicates that 1,25(OH)(2)D(3) can be produced locally in immune reaction sites. Moreover, the strict regulation of these enzymes by immune signals is highly suggestive for an autocrine/paracrine role in the immune system, and opens new treatment possibilities.