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The exquisite coupling between herpesvirus and human beings is the result of millions of years of relationship, coexistence, adaptation, and divergence. It is probably based on the ability to generate a latency that keeps viral activity at a very low level, thereby apparently minimising harm to its host. However, this evolutionary success disappears in immunosuppressed patients, especially in haematological patients. The relevance of infection and reactivation in haematological patients has been a matter of interest, although one fundamentally focused on reactivation in the post-allogeneic stem cell transplant (SCT) patient cohort. Newer transplant modalities have been progressively introduced in clinical settings, with successively more drugs being used to manipulate graft composition and functionality. In addition, new antiviral drugs are available to treat CMV infection. We review the immunological architecture that is key to a favourable outcome in this subset of patients. Less is known about the effects of herpesvirus in terms of mortality or disease progression in patients with other malignant haematological diseases who are treated with immuno-chemotherapy or new molecules, or in patients who receive autologous SCT. The absence of serious consequences in these groups has probably limited the motivation to deepen our knowledge of this aspect. However, the introduction of new therapeutic agents for haematological malignancies has led to a better understanding of how natural killer (NK) cells, CD4+ and CD8+ T lymphocytes, and B lymphocytes interact, and of the role of CMV infection in the context of recently introduced drugs such as Bruton tyrosine kinase (BTK) inhibitors, phosphoinosytol-3-kinase inhibitors, anti-BCL2 drugs, and even CAR-T cells. We analyse the immunological basis and recommendations regarding these scenarios. [ABSTRACT FROM AUTHOR]

High levels of inflammation play an important role in chronic heart failure (CHF). Patients with CHF have elevated levels of pro-inflammatory cytokines circulating systemically, mainly TNF and IL-6. However, there are almost no studies that relate these levels to the functional status of patients in CHF, much less to their CMV serostatus. In this study, patients with CHF (n=40; age=54.9 ± 6.3; New York Heart Association functional classification (NYHA, I-III) and healthy controls (n=40; age=53.5 ± 7.1) were analyzed. The serum concentrations of nine pro- and anti-inflammatory cytokines were measured by Luminex® xMap Technology and the basal level of mRNA expression of some immune molecules was quantified by TaqMan™ Array in CD4+ T-lymphocytes. The concentration of these cytokines in culture supernatants in response to anti-CD3 and LPS was also measured. The percentage of CD28null T-cells was determined, as well as the antibody titer against CMV. We found a higher concentration of all cytokines studied in CHF serum compared to healthy controls, as well as a direct correlation between functional status in CHF patients and levels of inflammatory cytokines. Moreover, the highest cytokine concentrations were found in patients with higher concentrations of lymphocytes lacking CD28 molecule. The cytokine production was much higher in CMV+ patients, and the production of these cytokines was found mainly in the T-lymphocytes of CMV+ patients in response to anti-CD3. Anti-CMV antibody levels were positively correlated with cytokine levels. The baseline expression of specific mRNA of the main molecules involved in the Th1 response, as well as molecules related to the CD4+CD28 null subset was higher in CMV+ patients. The cytokine concentrations are higher in CHF CMV+ patients and these concentrations are related to the production of antibodies against CMV. These high levels of cytokines are also associated with the more differentiated CD28null lymphocyte populations. All this, together with the dynamics of the pathology itself, makes CMV+ patients present a worse functional status and possibly a worse evolution of the pathology. [ABSTRACT FROM AUTHOR]

Immunosenescence in chronic heart failure (CHF) is characterized by a high frequency of differentiated T-lymphocytes, contributing to an inflammatory status and a deficient ability to generate immunocompetent responses. CMV is the best known inducer of T-lymphocyte differentiation, and is associated with the phenomenon of immunosenescence. In this study, we included 58 elderly chronic heart failure patients (ECHF), 60 healthy elderly controls (HEC), 40 young chronic heart failure patients (YCHF) and 40 healthy young controls (HYC). High differentiation of CD8+ T-lymphocytes was found in CMV-seropositive patients; however, the differentiation of CD4+ T-lymphocytes was increased in CMV-seropositive but also in CHF patients. Anti-CMV antibody titers showed positive correlation with more differentiated CD4+ and CD8+ subsets and inverse correlation with CD4/CD8 ratio. Immunosenescence found in CHF patients is mainly due to the dynamics of CMV-infection, since the differentiation of T-lymphocyte subsets is related not only to CMV-infection, but also to anti-CMV antibody titers. [ABSTRACT FROM AUTHOR]

Anti-CMV (cytomegalovirus) antibody titers are related to immune alterations and increased risk of mortality. To test whether they represent a marker of infection history, we analyzed the effect of viral reactivations on the production of specific antibodies in kidney transplant patients. We quantified CMV-DNAemia and antibody titers in 58 kidney transplant patients before transplantation and during a follow-up of 315 days (standard deviation, SD: 134.5 days). In order to calculate the intensity of the infection, we plotted the follow-up time of the infection on the x-axis and the number of DNA-CMV copies on the y-axis and calculated the area under the curve (CMV-AUC). The degree of T-lymphocyte differentiation was analyzed with flow cytometry, the cells were labelled with different monoclonal antibodies in order to distinguish their differentiation state, from naive T-cells to senescent T-cells. Peak viremia was significantly higher in patients experiencing a primary infection (VI) compared to patients experiencing viral reactivation (VR). Our data indicate that the overall CMV viral load over the course of a primary infection is significantly higher than in a reactivation of a previously established infection. Whereas patients who experienced an episode of CMV reactivation during the course of our observation showed increased levels of CMV-specific antibodies, patients who did not experience CMV reactivation (WVR) showed a drop in CMV antibody levels that corresponds to an overall drop in antibody levels, probably due to the continuing immunosuppression after the renal transplant. We found a positive correlation between the CMV viremia over the course of the infection or reactivation and the CMV-specific antibody titers in the examined patients. We also observed a positive correlation between anti-CMV titers and T-cell differentiation. In conclusion, our data show that anti-CMV antibody titers are related to the course of CMV infection in kidney transplant patients. [ABSTRACT FROM AUTHOR]

Shorter survival in the elderly has been associated with deterioration of the immune system and also with functional disability. To analyze the relationship between functional and immune impairment in older individuals, we studied 100 elderly who lived in a nursing home, were age matched, and grouped according to their functional status. We characterized cell subpopulations by flow cytometry, quantified TREC by RT-PCR, and measured the T-cell proliferation and activation response (IFN-γ by ELISPOT, CD69) against anti-CD3 and CMV. Specific antibody titers against influenza virus and CMV were determined by ELISA. Individuals with worse functional status had significantly higher levels of NK cells and fewer B cells. These poorly functioning elders also had a significantly lower proportion of CD4+ T cells, increased CD8+ T cells, and a decreased CD4/CD8 ratio. TREC levels in CD4+ T cells were significantly lower in individuals with a high disability. Lower TREC levels correlated with a lower frequency of naïve T-cell subpopulations (CD45RA+CCR7+) and higher percentages of effector cells (CD45RA−CCR7−). The functionally impaired group had lower anti-CD3 responses, but gradually increased responses against CMV. Similarly, the higher CMV titers were found in elderly with worse functional status. On the contrary, the functional response in vivo, and the titer of antibodies generated after vaccination against influenza virus, was higher in individuals with better performance status. In summary, we concluded that the functional decline of elderly individuals was clearly associated with the aging of their immune system, and the intensity of the response to CMV. [ABSTRACT FROM AUTHOR]