Serum Interleukin-2 and Neopterin Levels as Useful Markers for Treatment of Active Pulmonary Tuberculosis

Immune-endocrine network in diabetes-tuberculosis nexus: does latent tuberculosis infection confer protection against meta-inflammation and insulin resistance?

Tuberculosis patients with diabetes, have higher sputum bacillary load, delayed sputum conversion, higher rates of drug resistance, higher lung cavitary involvement and extra-pulmonary TB infection, which is called as "Diabetes-Tuberculosis Nexus". However, recently we have shown a reciprocal relationship between latent tuberculosis infection and insulin resistance, which has not been reported before. In this review, we would first discuss about the immune-endocrine network, which operates during pre-diabetes and incipient diabetes and how it confers protection against LTBI. The ability of IR to augment anti-TB immunity and the immunomodulatory effect of LTBI to quench IR were discussed, under IR-LTB antagonism. The ability of diabetes to impair anti-TB immunity and ability of active TB to worsen glycemic control, were discussed under "Diabetes-Tuberculosis Synergy". The concept of "Fighter Genes" and how they confer protection against TB but susceptibility to IR was elaborated. Finally, we conclude with an evolutionary perspective about how IR and LTBI co-evolved in endemic zones, and have explained the molecular basis of "IR-LTB" Antagonism" and "DM-TB Synergy", from an evolutionary perspective.

Elevated neopterin in tuberculosis and co-infection with HIV and the effect of treatment: A systematic review, meta-analysis, and meta-regression

BACKGROUND

Neopterin (NEO) is a marker of immune stimulation. Increased NEO levels have been associated with autoimmune diseases, infections, and malignancies. Studies of NEO alterations in tuberculosis (TB) with or without HIV co-infection show inconsistent results. Moreover, challenges exist regarding TB diagnosis in people with HIV.

METHODS

We did a systematic review and meta-analysis of studies comparing urinary, pleural, and blood NEO levels between patients with TB or HIV-TB co-infection as the case group and subjects without TB and HIV or subjects with HIV without TB as the control group, respectively.

RESULTS

Blood NEO levels in patients with active TB were higher than healthy controls, with a large effect size of 1.99. Patients with TB had higher blood NEO levels before anti-tuberculosis therapy (ATT) than after ATT for months or when treatment ended with moderate effect sizes (1.13-1.46). meta-analysis of studies of patients with HIV-TB co-infection yielded similar results, with higher blood NEO levels in patients than controls that remained significant in subgroups of studies on pulmonary TB (PTB) patients and serum NEO and higher blood NEO levels in patients before than after ATT.

CONCLUSION

Meta-analyses reveal alteration in NEO levels in different specimens, e.g., blood, urine, and pleural fluid, in patients with TB with or HIV-TB co-infection compared to the control groups. Future studies need to investigate the utility of NEO as a diagnostic/prognostic biomarker for TB. Also, cellular and molecular mechanisms linking NEO and TB remain to be addressed.

Tuberculosis comorbidity with rheumatoid arthritis: Gene signatures, associated biomarkers, and screening

Rheumatoid arthritis (RA) is known to be related to an elevated risk of infections because of its pathobiology and the use of immunosuppressive therapies. Reactivation of latent tuberculosis (TB) infection is a serious issue in patients with RA, especially after receiving anti-TNFs therapy. TNF blocking reinforces the TB granuloma formation and maintenance and the growth of Mycobacterium tuberculosis (Mtb). After intercurrent of TB infection, the standard recommendation is that the treatment with TNF inhibitors to be withheld despite its impressive effect on suppression of inflammation until the infection has resolved. Knowing pathways and mechanisms that are common between two diseases might help to find the mechanistic basis of this comorbidity, as well as provide us a new approach to apply them as therapeutic targets or diagnostic biomarkers. Also, screening for latent TB before initiation of an anti-TNF therapy can minimize complications. This review summarizes the shared gene signature between TB and RA and discusses the biomarkers for early detection of this infection, and screening procedures as well.

Comparison of serum neopterin levels in pulmonary tuberculosis patients with positive acid fast bacilli and inactive pulmonary tuberculosis

BACKGROUND

Tuberculosis (TB) is caused by infection with Mycobacterium tuberculosis. Sometimes it is difficult to distinguish between active and inactive pulmonary TB based on chest X-ray images. TB biomarkers are needed to diagnose active TB when TB bacilli are not detected either through microscopic examination, culture or geneXpert MTB/Rif. Neopterin can be used as an additional diagnosis and therapy monitoring as well as assessing activation of macrophage cells. This study aims to examine and comparing serum neopterin levels in new cases of pulmonary TB with positive AFB and inactive pulmonary TB.

METHODS

This was an analytic study with Cross-Sectional design conducted in Dr. Soetomo General Hospital Surabaya, Indonesia. The subjects of the study were the new cases of pulmonary TB with positive AFB and inactive pulmonary TB who met the inclusion and exclusion criteria. Blood serum was collected and examined to measure neopterin serum levels in patients by ELISA technique.

RESULTS

There was a significant difference of mean neopterin serum levels between the new cases of pulmonary TB with positive AFB and inactive pulmonary TB with a p-value <0.001 (74.92 nmol/l vs. 9.84 nmol/l). There was a significant difference in serum neopterin levels in each AFB grading in the new cases of pulmonary TB with positive AFB with a p-value <0.001 (60.10 nmol/l in AFB 1+, 80.81 nmol/l in AFB 2+, and 110.70 nmol/l in AFB 3+).

CONCLUSION

Serum neopterin levels in the new cases of pulmonary TB with positive AFB were higher than inactive pulmonary TB.

Efficacy of T Regulatory Cells, Th17 Cells and the Associated Markers in Monitoring Tuberculosis Treatment Response

Treatment monitoring is an essential aspect for tuberculosis (TB) disease management. Sputum smear microscopy is the only available tool for monitoring, but it suffers from demerits. Therefore, we sought to evaluate markers and cellular subsets of T regulatory (Treg) cells and T helper (Th) 17 cells in pulmonary TB patients (PTB) for TB treatment monitoring. Peripheral blood mononuclear cells (PBMCs) were stimulated in vitro (with purified protein derivative (PPD)) overnight which was followed by a polychromatic flow cytometry approach to study Treg and Th17 markers and cellular subsets in PTB (n = 12) undergoing antituberculous treatment (ATT). The baseline levels of these markers and cellular subsets were evaluated in normal healthy subjects (NHS). We observed a significant decrease in the expression of CD25 (p<0.01) marker and percentage of T-cell subsets like CD4⁺CD25⁺ (p<0.001) and CD4⁺CD25⁺CD39⁺ (p<0.05) at the end of intensive phase (IP) as well as in the continuation phase (CP) of ATT. A decrease in CD25 marker expression and percentage of CD4⁺CD25⁺ T cell subset showed a positive correlation to sputum conversion both in high and low sputum positive PTB. In eight PTB with cavitary lesions, only CD4⁺CD25⁺FoxP3 Treg subset manifested a significant decrease at the end of CP. Thus, results of this study show that CD25 marker and CD4⁺CD25⁺ T cells can serve as better markers for monitoring TB treatment efficacy. The Treg subset CD4⁺CD25⁺FoxP3 may be useful for prediction of favorable response in PTB with extensive lung lesions. However, these findings have to be evaluated in a larger patient cohort.

Biomarkers of Tuberculosis Severity and Treatment Effect: A Directed Screen of 70 Host Markers in a Randomized Clinical Trial

More efficacious treatment regimens are needed for tuberculosis, however, drug development is impeded by a lack of reliable biomarkers of disease severity and of treatment effect. We conducted a directed screen of host biomarkers in participants enrolled in a tuberculosis clinical trial to address this need. Serum samples from 319 protocol-correct, culture-confirmed pulmonary tuberculosis patients treated under direct observation as part of an international, phase 2 trial were screened for 70 markers of infection, inflammation, and metabolism. Biomarker assays were specifically developed for this study and quantified using a novel, multiplexed electrochemiluminescence assay. We evaluated the association of biomarkers with baseline characteristics, as well as with detailed microbiologic data, using Bonferroni-adjusted, linear regression models. Across numerous analyses, seven proteins, SAA1, PCT, IL-1β, IL-6, CRP, PTX-3 and MMP-8, showed recurring strong associations with markers of baseline disease severity, smear grade and cavitation; were strongly modulated by tuberculosis treatment; and had responses that were greater for patients who culture-converted at 8weeks. With treatment, all proteins decreased, except for osteocalcin, MCP-1 and MCP-4, which significantly increased. Several previously reported putative tuberculosis-associated biomarkers (HOMX1, neopterin, and cathelicidin) were not significantly associated with treatment response. In conclusion, across a geographically diverse and large population of tuberculosis patients enrolled in a clinical trial, several previously reported putative biomarkers were not significantly associated with treatment response, however, seven proteins had recurring strong associations with baseline radiographic and microbiologic measures of disease severity, as well as with early treatment response, deserving additional study.

Neopterin and oxidative stress markers in the diagnosis of extrapulmonary tuberculosis

BACKGROUND

Extrapulmonary tuberculosis (EPTB) often presents with nonspecific signs and symptoms. Further the paucibacillary nature of extrapulmonary specimens and irregular distribution of bacilli lower the sensitivity of conventional diagnostic methods making EPTB, a diagnostic dilemma.

OBJECTIVE

To study neopterin, protein carbonyl and malondialdehyde (MDA) in EPTB.

METHODS

Sixty nine clinically confirmed cases with an equal number of age and sex matched healthy controls were enrolled. Ziehl-Neelsen staining for acid fast bacilli and culture on Lowenstein-Jensen medium were performed on all the extrapulmonary specimens. Serum neopterin and protein carbonyl levels were estimated using commercial ELISA kits. Malondialdehyde was determined by measuring thiobarbituric acid reactive substances.

RESULTS

Serum neopterin, protein carbonyl and MDA levels were significantly discriminative for cases of EPTB from healthy controls (p < 0.05). Levels of all the three biomarkers under study significantly differed between culture as well as smear positive and negative cases. A positive correlation between neopterin and protein carbonyl was seen among the cases.

CONCLUSIONS

So far few studies have integrated combination of validated host biomarkers for active disease in EPTB. Our study suggests the potential diagnostic role of neopterin, protein carbonyl and MDA in EPTB.

C-reactive protein, Neopterin and Beta2 microglobulin levels pre and post TB treatment in The Gambia

Background

Tuberculosis is one of the leading causes of morbidity and mortality in developing countries. Analysis of the host immune response may help with generating point-of-care tests for personalised monitoring. Thus, the aim of this study was to assess the relationship between immune activation markers: C-reactive protein (CRP), Beta₂ microglobulin (B₂M) and Neopterin, disease severity prior to treatment and response to therapy in adult pulmonary TB patients.

Methods

HIV negative adult pulmonary TB index cases (n = 91) were recruited from the TB clinic at MRC, The Gambia. Plasma samples were collected at enrolment and at 2 and 6 months following TB treatment initiation. An enzyme linked immunosorbent assay (ELISA) was performed for evaluation of CRP, B₂M and Neopterin levels and correlated with clinical and microbiological parameters including strain of infection. Disease severity was determined using Chest X-ray (CXR), Body Mass Index (BMI) and sputum smear grade.

Results

Plasma levels of all three markers were highly elevated in patients at recruitment and declined significantly during TB therapy. No correlation with disease severity was seen at recruitment. CRP showed the most significant decrease by 2 months of treatment (p < 0.0001) whereas levels of B₂M and Neopterin showed little change by 2 months but a significant decrease by 6 months of treatment (p = 0.0002 and p < 0.0001 respectively). At recruitment, B₂M levels were significantly higher in subjects infected with Mycobacterium africanum (Maf) compared with those infected with Mycobacterium tuberculosis sensu stricto (Mtb) (p = 0.0075). In addition, while CRP and Neopterin showed a highly significant decline post-treatment regardless of strain (p < 0.0001 for all), B₂M showed differential decline depending on strain (p = 0.0153 for Mtb and p = 0.0048 for Maf) and levels were still significantly higher at 6 months in Maf compared to Mtb infected subjects (p = 0.0051).

Conclusion

Our findings suggest that activation markers, particularly CRP, may have a role in identifying good response to TB therapy regardless of the strain of infection and could be further developed as point-of-care tests. In addition, B₂M levels may allow differentiation between Mtb and Maf-infected subjects.

A non-specific biomarker of disease activity in HIV/AIDS patients from resource-limited environments

BACKGROUND

A general non-specific marker of disease activity that could alert the clinician and prompt further investigation would be of value in patients with HIV/AIDS, especially in resource limited environments.

OBJECTIVE

To investigate the potential of neopterin as non-specific biomarker in patients with advanced HIV/AIDS.

METHODS

Cross-sectional study in 105 HIV positive patients (75 on highly active antiretroviral treatment (HAART). Neopterin was assessed by enzyme linked immune-absorbent assay and cytokines by flow cytometry.

RESULTS

Neopterin levels were significantly higher (p<0.001) for the total patient than for the control group. Significant correlations between neopterin and plasma indicators of inflammation showed neopterin to be a good indicator of active inflammatory status and of the effect of HAART on the immune system. Neopterin was superior to C-reactive protein and to individual cytokines as indicator of immune deficiency. Increased neopterin levels were associated with a decline in albumin, haemoglobin and the albumin/globulin ratio, and with increases in red cell distribution width.

CONCLUSIONS

Plasma neopterin is a good non-specific biomarker of disease activity in HIV/AIDS patients. It is a good indicator of inflammatory activity, perpetuation of inflammation-associated co-morbidities, degree of immune deficiency and has predictive value for underlying disease, and for monitoring the HAART response.

Serum biomarkers of treatment response within a randomized clinical trial for pulmonary tuberculosis

RATIONALE

Biomarkers for monitoring response to anti-tuberculosis treatment are needed. We explored immune markers previously published as having predictive capability for 8 week culture status in 39 adults enrolled in a clinical trial in Kampala, Uganda.

METHODS

We consecutively selected 20 HIV-negative pulmonary TB subjects with positive cultures, and 19 subjects with negative cultures at the end of intensive phase therapy. At baseline and after 8 weeks, serum was assayed for nine cytokines and soluble cytokine receptors using multiplexed platforms or ELISA. We evaluated their association with week 8 culture status first using single-variable logistic models, then using cross-validated estimates of the C-statistic, a measure of discrimination, of candidate models including 2 or 3 analytes in addition to age.

RESULTS

All but one analyte decreased from baseline to week 8 (all p < 0.01). Individual biomarkers were not associated with 8 week culture status. Logistic models including increasing age, higher baseline soluble tumor necrosis factor receptor alpha 1 (sTNF-R1), and higher week 8 C-reactive protein (CRP) concentration classified subjects by culture status with up to 85% accuracy and acceptable discrimination (cross-validated C-statistic 0.76) and calibration (Hosmer-Lemeshow P > 0.2).

CONCLUSION

Exploratory post-hoc models including sTNF-R1, CRP, and age, classified 8 week culture status with promising accuracy.

Relationship between Serum Level of Interleukin-2 in Patients with Systemic Lupus Erythematosus and Disease Activity in Comparison with Control Group

BACKGROUND

Despite the large number of surveys, there are not any validated biomarkers for SLE disease activity till now. This study aimed to evaluate the relationship between serum level of IL-2 in patients with SLE and disease activity in comparison with control group.

MATERIALS AND METHODS

In this case-control study, 73 patients with lupus and 73 healthy subjects referred to the rheumatology clinic of 5 Azar Hospital in Gorgan (North of Iran).They were studied via convenience sampling during 2011-2012. Blood samples were taken from both groups and serum levels of interleukin -2 measured by Avi Bion Human IL-2 ELISA kit. Serum Level of IL-2 greater than 15 pg/ml defined positive and lesser than this amount defined negative. Disease activity evaluated with SLE disease activity index. Score greater than or equal to three or four defined as active disease. Data analysis conducted by SPSS software (version 16) and by using descriptive statistics and statistical tests.

RESULTS

Serum level of IL-2 was positive in 45.2% of sample studied and negative in 54.8% in case group, while in control group, serum level of IL-2 only in 11% of sample studied was positive and in 89% was negative. Statistical analysis indicated a significant relationship between serum level of IL-2 and the SLE disease activity index (p=0.025).

CONCLUSION

This study showed the relationship between serum levels of IL-2 and disease activity, so this biomarker can be used as a clinical indicator for assessing disease activity in patients with SLE.

[The dependence of the inflammatory reaction on the properties of mycobacterium tuberculosis and the course of specific pulmonary process]

The systemic analysis of the inflammatory process in untreated patients with newly diagnosed infiltrative-destructive tuberculosis has been performed in the context of host mycobacterium interaction. Variability of acute phase proteins (APP) reflecting mobilization of nonspecific protective systems of the body did not depend on cytotoxicity of Mycobacterium tuberculosis (MBT). In 87.5% of patients the dependence between effectiveness of antitubercular chemotherapy (for three months) and combination of MBT characteristics and initial APP levels was found. Patients with effectiveness of therapy, which was inadequate to MBT cytotoxicity, were characterized by its dependence on the APP level and MBT sensitivity to antitubercular agents. Results of multifactorial analysis of parameters reflecting intensity of the inflammatory response, pathological process in the lungs, and characteristics of MBT suggest that the overall result of the host-pathogen interactions primarily depend on adequateness of protective systems of the body

Neopterin in Diagnosis and Monitoring of Infectious Diseases

Neopterin is produced by activated monocytes, macrophages, and dendritic cells upon stimulation by interferon gamma produced by T-lymphocytes. Quantification of neopterin in body fluids has been achieved by standard high-performance liquid chromatography, radioimmunoassays, and enzyme-linked immunosorbent assays. Neopterin levels predict HIV-related mortality more efficiently than clinical manifestations. Successful highly active antiretroviral therapy is associated with a decrease in neopterin levels. Elevated neopterin levels were associated with hepatitis by hepatitis A, B, and C viruses. Serum neopterin levels were found to be a predictor of response to treatment of chronic HCV infection with pegylated interferon combined with ribavirin. Neopterin levels of patients with pulmonary tuberculosis were found to be higher in patients with more extensive radiological changes. Elimination of blood donors with elevated neopterin levels to reduce risk of transmission of infections with known and unknown viral pathogens has been undertaken. Neopterin measurement is hereby more cost effective but less sensitive than screening using polymerase chain reaction based assays. In conclusion neopterin is a nonspecific marker of activated T-helper cell 1 dominated immune response. It may be a useful marker for monitoring of infectious disease activity during treatment and for more accurate estimation of extent of disease and prognosis.

Common patterns and disease-related signatures in tuberculosis and sarcoidosis

In light of the marked global health impact of tuberculosis (TB), strong focus has been on identifying biosignatures. Gene expression profiles in blood cells identified so far are indicative of a persistent activation of the immune system and chronic inflammatory pathology in active TB. Definition of a biosignature with unique specificity for TB demands that identified profiles can differentiate diseases with similar pathology, like sarcoidosis (SARC). Here, we present a detailed comparison between pulmonary TB and SARC, including whole-blood gene expression profiling, microRNA expression, and multiplex serum analytes. Our analysis reveals that previously disclosed gene expression signatures in TB show highly similar patterns in SARC, with a common up-regulation of proinflammatory pathways and IFN signaling and close similarity to TB-related signatures. microRNA expression also presented a highly similar pattern in both diseases, whereas cytokines in the serum of TB patients revealed a slightly elevated proinflammatory pattern compared with SARC and controls. Our results indicate several differences in expression between the two diseases, with increased metabolic activity and significantly higher antimicrobial defense responses in TB. However, matrix metallopeptidase 14 was identified as the most distinctive marker of SARC. Described communalities as well as unique signatures in blood profiles of two distinct inflammatory pulmonary diseases not only have considerable implications for the design of TB biosignatures and future diagnosis, but they also provide insights into biological processes underlying chronic inflammatory disease entities of different etiology.

Surrogate markers of infection: interrogation of the immune system

Infectious diseases remain the greatest causes of morbidity and mortality in global terms. As much of the burden occurs in the developing world, limited access to diagnostic testing has hampered the diagnosis and treatment of these conditions, while, in the developed world, the cost of managing infectious diseases remains considerable. Despite the size of the problem there remains an ongoing need for tests that improve diagnostic sensitivity and specificity, provide more rapid diagnoses, are available for point-of-care testing in remote regions, and can help inform therapeutic decision-making by identifying resistance patterns or patient outcomes. This article discusses the background to biomarker development for infectious diseases, some current assays that are providing useful information regarding the host's response to infection (using examples such as Cytomegalovirus and Mycobacterium tuberculosis), as well as likely future technologies and their limitations.

Differential Levels of Cytokines and Soluble Fas Ligand between Tuberculous and Malignant Effusions

Tuberculous pleurisy, which is characterized by an extensive inflammatory exudate in the pleural space, is a common manifestation of extrapulmonary tuberculosis caused by Mycobacterium tuberculosis infection but is difficult to diagnose. This study compared concentrations of three cytokines (interferon-γ and interleukin [IL]−2 and −4) and soluble Fas ligand in serum and pleural effusions from 36 patients with tuberculous pleurisy, 30 with malignant pleurisy and 30 healthy volunteers. Interferon-γ concentration was significantly higher in serum and pleural effusions, and the concentration of soluble Fas ligand was significantly higher in pleural effusion, from patients with tuberculous pleurisy than in those with malignant pleurisy. Levels of IL-2 and IL-4 were also raised in serum, but failed to reach statistical significance. Interferon-γ and soluble Fas ligand levels were significantly higher in pleural effusion than in serum. Pleural soluble Fas ligand concentrations correlated linearly with those of interferon-γ in patients with tuberculous pleurisy. These findings suggest a predominant T-helper-1 response to M. tuberculosis infection.

Biomarkers and diagnostics for tuberculosis: progress, needs, and translation into practice

Human infection with Mycobacterium tuberculosis can progress to active disease, be contained as latent infection, or be eradicated by the host response. Tuberculosis diagnostics classify a patient into one of these categories. These are not fixed distinct states, but rather are continua along which patients can move, and are affected by HIV infection, immunosuppressive therapies, antituberculosis treatments, and other poorly understood factors. Tuberculosis biomarkers-host or pathogen-specific-provide prognostic information, either for individual patients or study cohorts, about these outcomes. Tuberculosis case detection remains difficult, partly because of inaccurate diagnostic methods. Investments have yielded some progress in development of new diagnostics, although the existing pipeline is limited for tests for sputum-smear-negative cases, childhood tuberculosis, and accurate prediction of reactivation of latent tuberculosis. Despite new, sensitive, automated molecular platforms for detection of tuberculosis and drug resistance, a simple, inexpensive point-of-care test is still not available. The effect of any new tests will depend on the method and extent of their introduction, the strength of the laboratories, and the degree to which access to appropriate therapy follows access to diagnosis. Translation of scientific progress in biomarkers and diagnostics into clinical and public health programmes is possible-with political commitment, increased funding, and engagement of all stakeholders.

Gene expression profiling of peripheral mononuclear cells in lame dairy cows with foot lesions

Lameness is a major health issue and likely the single most common cause of pain and discomfort in dairy cattle. Appropriate treatment is delayed or neglected due, in part, to lack of reliable detection. Assessment of cows with lameness is currently limited to subjective visual scoring systems based on locomotion and posture abnormalities. These systems are unreliable to detect lameness, and therefore, a large number of cows remain undiagnosed. The objective of this research was to search for potential biomarkers for lameness-associated painful inflammatory foot lesions in dairy cattle using microarray-based gene expression profiling of peripheral blood mononuclear cells (PBMC). BOTL5 microarrays spotted in duplicate with cDNA representing bovine immune response genes were interrogated with cDNA samples in an eight-array, balanced complete block design with dye swap. Samples from eight lame cows with inflammatory foot lesions and from eight sound cows were pair-matched by age, weight, days in lactation, and pregnancy status at time of PBMC collection and directly compared with each other on individual arrays. Statistical analysis of resulting fluorescence intensity data revealed 31 genes that were putatively differentially expressed in lame versus sound cows (P<0.05). Of these, BLASTn analysis and gene ontology information showed that 28 genes had high similarity or homology to known human and/or rodent genes. Validation of 15 of these genes known to be important in inflammation and pain was carried out using relative quantitative real-time RT-PCR, which confirmed the up-regulation of interleukin (IL)-2 (12.68+/-1.47-fold increase) and IL-10 (2.39+/-0.55-fold increase), matrix metalloproteinase-13 (MMP-13) (10.44+/-1.14-fold increase), and chemokine C-C motif receptor-5 (CCR5) (5.26+/-1.05-fold increase), in lame relative to sound cows (P< or =0.05). Similarly, granulocyte-macrophage colony-stimulating factor receptor alpha chain precursor (GM-CSF-R-alpha) (2.30+/-0.63-fold increase) and IL-4 (2.06+/-0.59-fold increase) showed a tendency (P=0.10) for up-regulation in lame compared to sound cows. PBMC co-expression of IL-2, MMP-13, CCR5 and IL-10, and potentially IL-4 and GM-CSF-R-alpha appears to be a promising, objective sign of lameness-related inflammatory foot lesions in dairy cattle. In conclusion, this study revealed potential biomarkers of the presence of foot lesions that could boost diagnostic accuracy of lameness and, ultimately, help identify animals in need of pain relief.