Interferon-gamma Release Assay Responses Research Articles

High vaccination coverage and infection rate result in a robust SARS-CoV-2-specific immunity in the majority of liver cirrhosis and transplant patients: A single-center cross-sectional study.

In the third year of the SARS-CoV-2 pandemic, little is known about the vaccine- and infection-induced immune response in liver transplant recipients (LTR) and liver cirrhosis patients (LCP). This cross-sectional study assessed the vaccination coverage, infection rate, and the resulting humoral and cellular SARS-CoV-2-specific immune responses in a cohort of LTR and LCP at the University Medical Center Hamburg-Eppendorf, Germany between March and May 2023. Clinical and laboratory data from 244 consecutive patients (160 LTR and 84 LCP) were collected via chart review and a patient survey. Immune responses were determined via standard spike(S)- and nucleocapsid-protein serology and a spike-specific Interferon-gamma release assay (IGRA). On average, LTR and LCP were vaccinated 3.7 and 3.3 times, respectively and 59.4% of patients received ≥4 vaccinations. Altogether, 68.1% (109/160) of LTR and 70.2% (59/84) of LCP experienced a SARS-CoV-2 infection. Most infections occurred during the Omicron wave in 2022 after an average of 3.0 vaccinations. Overall, the hospitalization rate was low (<6%) in both groups. An average of 4.3 antigen contacts by vaccination and/or infection resulted in a seroconversion rate of 98.4%. However, 17.5% (28/160) of LTR and 8.3% (7/84) of LCP demonstrated only low anti-S titers (<1000 AU/ml), and 24.6% (16/65) of LTR and 20.4% (10/59) of LCP had negative or low IGRA responses. Patients with hybrid immunity (vaccination plus infection) elicited significantly higher anti-S titers compared with uninfected patients with the same number of spike antigen contacts. A total of 22.2% of patients refused additional booster vaccinations. By spring 2023, high vaccination coverage and infection rate have resulted in a robust, mostly hybrid, humoral and cellular immune response in most LTR and LCP. However, booster vaccinations with vaccines covering new variants seem advisable, especially in patients with low immune responses and risk factors for severe disease.

Cellular immune response to SARS-CoV-2 in patients with primary antibody deficiencies.

Primary antibody deficiencies (PAD) are inborn defects of the immune system that result in increased susceptibility to infections. Despite the reduced response to vaccination, PAD patients still benefit from it by reducing the risk of severe infections and complications. SARS-CoV-2 vaccines are recommended in PAD patients, but their immune effects are poorly studied. Here, we analyze virus-specific T-cell responses in PAD patients after booster vaccination against SARS-CoV-2. The study included 57 adult PAD patients on long-term immunoglobulin replacement therapy (IgRT) diagnosed with X-linked agammaglobulinemia (XLA; n = 4), common variable immunodeficiency (CVID; n = 33), isotype defects or IgG subclass deficiency (n = 6), and unclassified IgG deficiency (n = 14). Of those, 49 patients (86%) received vaccination against SARS-CoV-2 using mRNA vaccine (Pfizer-BioNTech). T-cell responses were assessed at a median of 21 (13 - 30) weeks after the booster dose (mainly the third dose) using commercially available interferon-gamma release assay (IGRA) with recombinant SARS-CoV-2 spike S1 protein. Vaccinated PAD patients showed an increased (3.8-fold, p = 0.004) release of IFN-γ upon S1 stimulation. In this group, we also documented higher serum levels of anti-SARS-CoV-2 IgG (4.1-fold, p = 0.01), although they were not associated with IGRA results. Further subgroup analysis revealed very similar IGRA responses in CVID and unclassified IgG deficiencies that were 2.4-fold increased compared to XLA and 5.4-fold increased compared to patients with isotype defects or IgG subclass deficiencies (e.g., vs. CVID: p = 0.016). As expected, CVID and XLA patients showed decreased serum titers of anti-SARS-CoV-2 antibodies compared to other studied groups (e.g., CVID vs. unclassified IgG deficiency: 4.4-fold, p = 0.006). The results did not depend directly on IgRT mode or dose, number of vaccine doses and time from the last booster dose, and clinical manifestations of PAD. Interestingly, anti-SARS-CoV-2 titers were positively correlated with serum immunoglobulin levels before IgRT (e.g., for IgA: r = 0.45, p<0.001; for IgG: r = 0.34, p = 0.009) and the percentage of peripheral blood NK cells (r = 0.48, p<0.001). Our results documented satisfactory in vitro cellular immune response in PAD patients after booster SARS-CoV-2 vaccination. Therefore, even patients with agammaglobulinemia should benefit from vaccination due to the apparent induction of cell-mediated immunity, which, together with IgRT, grants comprehensive protection against the pathogen.

Impact of different classes of immune-modulating treatments on B cell-related and T cell-related immune response before and after COVID-19 booster vaccination in patients with immune-mediated diseases and primary immunodeficiency: a cohort study

ObjectivesTo evaluate the potential of immunosuppressed patients to mount B-cell and T-cell responses to COVID-19 booster vaccination (third vaccination).MethodsPatients with primary immunodeficiency (PID), immune-mediated inflammatory diseases (IMIDs) on CD20-depleting treatment...

Glucocorticoids selectively affect the memory T cell response to SARS-Cov2 spike in vaccinated and post-infected patients with systemic lupus erythematosus

Immune response to vaccines and pathogens remains unclear in patients with systemic lupus erythematosus (SLE). To investigate this, a single-center retrospective study was conducted with 47 SLE patients vaccinated against COVID-19, including 13 who subsequently developed an asymptomatic/mild disease. As compared to controls, post-vaccine response against Spike was reduced in SLE patients when considering both memory T-cells in a whole blood interferon gamma release assay (IGRA-S) and IgG anti-Spike antibody (Ab) responses. The SLE-associated defective IGRA-S response was associated with a serum albumin level below 40 g/L and with the use of glucocorticoids, while a defective IgG anti-Spike Ab response was associated with lower levels of anti-dsDNA and anti-SSA/Ro 52 kDa Abs. IGRA-S and IgG anti-Spike responses were independent from SLE activity and clinical phenotype, low complement, hypergammaglobulinemia, and lymphopenia. As compared to controls, SLE patients showed a rapid decay of anti-Spike T-cell memory and stable IgG anti-Spike Ab responses. In conclusion, both T cell and humoral anti-Spike responses were independently affected in our SLE patients cohort, which supports the exploration of both responses in the follow-up of SLE patients and especially in those receiving glucocorticoids.

Pediatric solid organ transplant recipients demonstrate robust cell-mediated and humoral responses to three doses of mRNA SARS-CoV-2 vaccine

Pediatric solid organ transplant recipients (pSOTR) often demonstrate suboptimal vaccine responses and are not included in severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) vaccine efficacy trials. This population has shown variable humoral immunity following SARS‐CoV‐2 vaccination, and no studies have assessed cell‐mediated responses after SARS‐CoV‐2 vaccination in pSOTR. SARS‐CoV‐2‐specific interferon‐gamma release assay (IGRA), immunoglobulin G (IgG), and receptor‐binding domain (RBD)‐angiotensin‐converting enzyme 2 (ACE2) blocking antibody (Ab) were measured in pSOTR aged 5–17 years after 2–3 doses of SARS‐CoV‐2 mRNA vaccine. In all, 33 subjects were included, with 25 tested after the second dose of mRNA vaccine (V2) and 21 tested after the third dose of mRNA vaccine (V3). Of the 19 subjects who had IgG testing after V3, 100.0% (19/19) had a positive IgG response. Of the 17 subjects who had IGRA testing after V3, 94.1% (16/17) had a positive IGRA response. RBD‐ACE2 blocking antibody increased significantly from V2 to V3 (p = .007). Subjects <1 year from transplant demonstrated a significantly larger increase in RBD‐ACE2 blocking Ab from V2 to V3 than did those >1 year from transplant (p = .05). SARS‐CoV‐2 vaccination induces humoral and cell‐mediated responses in the majority of pSOTR, with improved quantitative humoral response after three doses.

Evaluation of humoral and cellular response to third dose of BNT162b2 mRNA COVID-19 vaccine in patients treated with B-cell depleting therapy

Objectiveto investigate the responses to mRNA COVID-19 vaccines in a cohort of immunosuppressed patients affected by immune-mediated inflammatory diseases (IMID). Methodswe have measured humoral and cellular immunity using quantitative IgG anti-SARS-CoV-2 Spike antibody (anti-S-IgG), neutralization assays and specific interferon-gamma (IFN-g) release assay (IGRA) before and after the third dose of BNT162b2. The response of those on anti-CD20 (n = 18) was then compared with healthy controls (HC, n = 18) and IMID naïve to anti-CD20 drugs (n = 13). Resultsa third BNT162b2 dose is highly immunogenic in IMID patients naïve to anti-CD20, as 100% of the subjects seroconverted compared to the 55% in anti-CD20. The rate of IGRA response was of 79% in anti-CD20, 50% in IMID naïve to anti-CD20, 100% in HC. Among those who have seroconverted, IMID patients had significantly reduced anti-S-IgG and neutralization titers compared to HC, whereas no significant difference was observed when comparing anti-CD20 and HC. Furthermore, 13% of anti-CD20 and 7.7% of IMID were simultaneously negative for both neutralizing antibodies and IGRA after three doses. Conclusion: these data draw attention to the immunogenicity of COVID-19 vaccination in treated IMID, taking specific groups into consideration for vaccination program.

Immune response to COVID-19 vaccination is attenuated by poor disease control and antimyeloma therapy with vaccine driven divergent T-cell response.

SummaryMyeloma patients frequently respond poorly to bacterial and viral vaccination. A few studies have reported poor humoral immune responses in myeloma patients to COVID‐19 vaccination. Using a prospective study of myeloma patients in the UK Rudy study cohort, we assessed humoral and interferon gamma release assay (IGRA) cellular immune responses to COVID‐19 vaccination post second COVID‐19 vaccine administration. We report data from 214 adults with myeloma (n = 204) or smouldering myeloma (n = 10) who provided blood samples at least three weeks after second vaccine dose. Positive Anti‐spike antibody levels (> 50 iu/ml) were detected in 189/203 (92.7%), positive IGRA responses were seen in 97/158 (61.4%) myeloma patients. Only 10/158 (6.3%) patients were identified to have both a negative IGRA and negative anti‐spike protein antibody response. In all, 95/158 (60.1%) patients produced positive results for both anti‐spike protein serology and IGRA. After adjusting for disease severity and myeloma therapy, poor humoral immune response was predicted by male gender. Predictors of poor IGRA included anti‐CD38/anti‐BCMA (B‐cell maturation antigen) therapy and Pfizer‐BioNTech vaccination. Further work is required to understand the clinical significance of divergent cellular response to vaccination.

Comparing Humoral and Cellular Adaptive Immunity during Convalescent Phase of COVID-19 in Hemodialysis Patients and Kidney Transplant Recipients.

Background. It is still unclear whether COVID-19 convalescent kidney transplant recipients (KTR) and hemodialysis (HD) patients can develop anti-SARS-CoV-2 adaptive immunity. The aim was to characterize and compare the immune response to the virus in HD patients and KTR. Methods. The study included 26 HD patients and 54 KTR—both convalescent (14 HD, 25 KTR) and unexposed. The immune response was assessed by determining the anti-SARS-CoV-2 antibodies in serum and specific T cell response via the interferon-gamma release assay (IGRA). Moreover, blood-morphology-derived parameters, immune cell phenotypes, and acute phase reactants were evaluated. Results. KRT and HD convalescents presented similar serum levels of anti-SARS-CoV-2 IgG and IgA. A negative correlation occurred between IgG and time after the infection was observed. There was a strong relationship between the prevalence of anti-SARS-CoV-2 cellular and humoral responses in both groups. Convalescent IGRA response was significantly higher in HD patients compared to KTR. Conclusions. HD patients and KTR develop humoral and cellular responses after COVID-19. The antibodies levels are similar in both groups of patients. SARS-CoV-2-reactive T cell response is stronger in HD patients compared to KTR. The SARS-CoV-2-specific IgG level decreases with time while IgA and a cellular response are maintained. IGRA proved to be a valuable test for the assessment of specific cellular immunity in immunocompromised HD patients and KTR.

The Magnitude of Interferon Gamma Release Assay Responses in Children With Household Tuberculosis Contact Is Associated With Tuberculosis Exposure and Disease Status.

The clinical utility of the magnitude of interferon gamma (IFNγ) in response to mycobacterial antigens is unknown. We assessed the association between quantitative IFNγ response and degree of Mycobacterium tuberculosis exposure, infection and tuberculosis (TB) disease status in children. We completed cross-sectional analysis of children (≤15 years) exposed to an adult with bacteriologically confirmed TB, 2007-2012 in Cape Town, South Africa. IFNγ values were reported as concentrations and spot forming units for the QuantiFERON-TB Gold In-Tube (QFT-GIT) and T-SPOT.TB, respectively. Random-effects linear regression was used to investigate the relation between the M. tuberculosis contact score, clinical phenotype (TB diseased, infected, uninfected) and IFNγ▪response as outcome, adjusted for relevant covariates. We analyzed data from 669 children (median age, 63 months; interquartile range, 33-108 months). A 1-unit increase in M. tuberculosis contact score was associated with an increase of IFNγ 0.60 international unit/mL (95% confidence interval [CI], 0.44-0.76 international unit/mL), and IFNγ spot forming unit 2 counts (95% CI, 1-3). IFNγ response was significantly lower among children with M. tuberculosis infection compared with children with TB disease (β = -1.42; 95% CI, -2.80 to -0.03) for the QFT-GIT, but not for the T-SPOT.TB. This association was strongest among children 2-5 years (β = -2.35 years; 95% CI, -4.28 to -0.42 years) and absent if <2 years. The magnitude of IFNγ response correlated with the degree of recent M. tuberculosis exposure, measured by QFT-GIT and T-SPOT.TB, and was correlated with clinically relevant TB phenotypes using the QFT-GIT. IFNγ values are not only useful in estimating the risk of M. tuberculosis infection but may also support the diagnosis of TB disease in children. The magnitude of IFNγ response correlated with the degree of recent M. tuberculosis exposure, measured by QFT-GIT and T-SPOT.TB, and was correlated with clinically relevant TB phenotypes using the QFT-GIT. IFNγ values are not only useful in estimating the risk of M. tuberculosis infection but may also support the diagnosis of TB disease in children.

Differential RD-1-specific IFN-γ host responses to diverse Mycobacterium tuberculosis strains in HIV-uninfected persons may be explained by genotypic variation in the ESX-1 region

ObjectivesBetween-person variability in T-cell-specific interferon-gamma release assay (IGRA) responses and discordance between IGRA test formats are poorly understood. MethodsWe evaluated the IFN-γ responses (QuantiFERON-TB Gold-In-Tube [QFT-GIT] and TSPOT-TB) stratified according to the Mycobacterium tuberculosis spoligotype of the culture isolate obtained from the same patients with confirmed active tuberculosis (n = 91). We further analysed differences within the RD-1-encoding ESX-1 region between the different strain types using whole genome sequencing. ResultsIn HIV-uninfected patients, TSPOT.TB and QFT-GIT IFN-γ responses were 5-fold (p < 0.01) and 2-fold higher (p < 0.05) for those infected with family 33 compared to the LAM strain (additionally, TSPOT.TB responses were 5.6-fold [p < 0.05] and 2.6-fold higher [p < 0.05] for the patients infected with the family 33 versus the X strain and Beijing versus the LAM strain, respectively). Multivariate analysis revealed that strain type (determined by spoligotyping) was independently associated with the magnitude of the IGRA response (varied by IGRA test type) and this is likely explained by variability in the ESX-1 region of Mycobacteriumtuberculosis (determined by next-generation sequencing). ConclusionsThese data have implications for the understanding of between-person heterogeneity in IGRA responses, Mycobateriumtuberculosis-specific host immunity, and the discordance between different IGRA test formats.

Estimating the annual risk of tuberculosis infection in Japan from interferon-gamma release assay data

To assess tuberculosis transmission frequency at a population level, the age-dependent Mantoux test has been used widely to estimate the annual risk of infection (ARI) with Mycobacterium tuberculosis. However, the widespread Bacille Calmette-Guerin (BCG) immunization program implemented in Japan in the 20th century has made natural infections with M. tuberculosis difficult to distinguish from immune responses against this vaccine. Consequently, a recognized alternative method for measuring the frequency of primary infections, the interferon-gamma release assay (IGRA), which partially decays as a function of time after infection, is used. We aimed to estimate the ARI in Japan from IGRA data along with its response decay information using mathematical modeling. Devising a partial differential equation system, we computed the probability of IGRA positivity as a function of time and age, accounting for the time-varying force of infection and decay function of the IGRA response. Jointly estimating the force of infection and the parameters governing the decay function of the IGRA response, we found that the age-dependent increasing pattern of the IGRA response was captured by the proposed simple model, yielding estimates of the time-dependent force of infection. ARI decreased as a function of time in the study subjects for all geographic locations. By the year 2030, our model showed that the median age of infection is predicted to be delayed by 40–50 years compared with that in 1940. The geographic variations in the ARI were striking, ranging from under 0.1% to 0.6% in 2018, which echoes the longstanding notion of highly heterogeneous geographical tuberculosis transmission in Japan.

CD4 T-cell cytokine correlates of diagnostic tests for latent tuberculous infection in HIV-1-infected subjects

Public human immunodeficiency virus (HIV) clinic and tuberculosis (TB) clinics in Kampala, Uganda. To examine TB-specific CD4 T-cell single and polyfunctional cytokine correlates of clinical diagnostic tests for latent tuberculous infection (LTBI) in HIV-1-infected subjects. Thirty antiretroviral therapy-naïve HIV-1-infected adults without active TB disease underwent clinical tuberculin skin test (TST), interferon-gamma release assay (IGRA), and in vitro flow cytometry analysis on cells stimulated with purified protein derivative (PPD) and TB antigens early secreted antigenic target 6 + culture filtrate protein 10 (EC) for frequencies of interleukin (IL) 2, IL-17, interferon-gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) expressing cells. PPD-specific CD4 T-cell expression of TNF-α and IFN-γ was higher in the TST-positive than in the TST-negative group. EC-specific CD4 T-cell expression of TNF-α and IL-2 was higher in the TST+ group than in the TST- group. Expression of both PPD and EC-specific expression of IL-2, IFN-γ and TNF-α were greater in IGRA-positive than in IGRA-negative subjects. The TST+ group exhibited greater polyfunctionality than the TST- group. All cytokine combinations that contained TNF-α correlated strongly with TST size. While IL-2, IFN-γ and TNF-α correlate with clinical tests of LTBI, TNF-α is the dominant cytokine correlating with both TST size and magnitude of IGRA response.

Tuberculosis and Pregnancy: An Updated Systematic Review

Tuberculosis (TB) affects women, especially in the child-bearing years. TB is associated with a poorer outcome of pregnancy, although this may be due to the general risk factors for TB, namely poverty, malnutrition and overcrowding. New studies have shown that symptom screening has a low sensitivity and specificity, but is improved by the addition of a tuberculin skin test (TST) or interferon-gamma release assay (IGRA) or, in high incidence areas, DNA amplification tests (e.g. Xpert MTB/RIF). TB-HIV co-infection is a common cause of mortality and morbidity in pregnancy. The diagnostic process remains the same in pregnancy, but non-specific symptoms and extra pulmonary disease demand a higher level of suspicion of TB. Standard first-line treatment is safe in pregnancy. Data on second-line drugs in pregnancy is still limited, but injectable drugs may affect the hearing and balance of the fetus. The IGRA responses appear to change during pregnancy, with more positive responses after delivery. The increasing incidence of drug-resistant TB, especially in Eastern Europe and Central Asia, requires an evaluation of the safety of second-line drugs in pregnancy.

Ring enhancing lesion in brain and decreasing interferon gamma release assay response

Ring enhancing lesion in brain and decreasing interferon gamma release assay response

S61 Serial IGRA testing to identify recently acquired LTBI in contacts of smear positive pulmonary tuberculosis

IntroductionWe have previously reported prospective data of TB risk in close contacts of tuberculosis with single step interferon gamma release assay (IGRAs) screening 8–12 weeks after index notification and shown...

Factors associated with latent tuberculosis among asylum seekers in Switzerland: a cross-sectional study in Vaud County

BackgroundScreening and treatment of latent tuberculosis infection (LTBI) in asylum seekers (AS) may prevent future cases of tuberculosis. As the screening with Interferon Gamma Release Assay (IGRA) is costly, the objective of this study was to assess which factors were associated with LTBI and to define a score allowing the selection of AS with the highest risk of LTBI.MethodsIn across-sectional study, AS seekers recently arrived in Vaud County, after screening for tuberculosis at the border were offered screening for LTBI with T-SPOT.TB and questionnaire on potentially risk factors. The factors associated with LTBI were analyzed by univariate and multivariate regression.ResultsAmong 393 adult AS, 98 (24.93%) had a positive IGRA response, five of them with active tuberculosis previously undetected. Six factors associated with LTBI were identified in multivariate analysis: origin, travel conditions, marital status, cough, age and prior TB exposure. Their combination leads to a robust LTBI predictive score.ConclusionsThe prevalence of LTBI and active tuberculosis in AS is high. A predictive score integrating six factors could identify the asylum seekers with the highest risk for LTBI.

Reply to Herzmann et al

To The Editor—We thank Herzmann and colleagues for their interest, comments, and description of findings related to our proposed definition for the early and asymptomatic disease state “incipient tuberculosis (TB)” [1]. Herzmann et al describe a study in which 5 of 25 individuals who were household contacts of TB patients had an interferon-gamma release assay (IGRA) result that was negative testing peripheral blood and positive testing bronchoalveolar lavage (BAL) fluid. They propose including localized immune responses in the category of “incipient TB” by expanding our definition to encompass the “presence of measurable localized M. tuberculosis specific immune responses in the absence of a generalized M. tuberculosis specific immune response” [ref Herzmann]. The intent of our characterization of a state of incipient TB was to identify, among asymptomatic immunocompetent individuals with TB exposure, a group of individuals with radiographically minimal disease who are at greater risk for progression to active TB, compared with those without radiographic abnormalities. A localized immune response, while reflecting infection after exposure, does not necessarily imply either disease or a high likelihood of progression to disease. While we acknowledge that the radiographic abnormalities in our proposed definition for incipient TB lack specificity for M. tuberculosis infection, they still suggest evidence of early disease in a person exposed to TB and are associated with histopathological changes [2]. We deliberately used the term “incipient” since it connotes “an initial stage” of something “beginning to happen or develop” (Oxford English Dictionary) to distinguish early TB from latent M. tuberculosis infection. Further, the observations substantiating the prognostic impact of radiographic abnormalities for the development of culture-positive “proven,” “active” TB have been extensively demonstrated in both isoniazid prophylaxis trials [3] and treatment trials for culture-negative TB [4]. The rationale for the diagnostic category of “culture-negative TB” in patients with compatible chest radiographic findings is based on the observed high rate of progression, radiographically and microbiologically, to culture-positive disease in the absence of treatment [5]. In both situations, the greater the radiographic abnormality, the greater the risk of progression to culture-positive disease. In conclusion, although the observations of Herzmann et al are important and very interesting, they do not provide guidance on whether to “treat or not treat.” It remains to be learned whether their observation of a localized IGRA response by pulmonary alveolar mononuclear cells from TB-exposed patients in the absence of a systemic IGRA response confers a higher or a lower likelihood of progression to active TB, compared with those without such responses. Plausibly, a vigorous local immune response, as evidenced by a locally positive IGRA result, might be protective. Furthermore, Herzmann et al do not provide data whether the localized IGRA response was associated with any radiographic abnormalities or on the local IGRA response in the remaining 15 of 40 patients with systemic positive IGRA results. For these reasons, we feel that a pulmonary M. tuberculosis–specific immune response in the absence of a systemic M. tuberculosis–specific immune response, while certainly a sign of infection, cannot be considered indicative of early TB. We look forward to follow-up clinical data on these immunologically well-characterized TB-exposed individuals from Herzmann et al and the “TB or not TB” Consortium so that we may better learn the prognostic attributes that would justify early antituberculous treatment.