Activated phenotype in neutrophils and monocytes from patients with primary proliferative polycythaemia

Diagnostic performance of Neutrophil CD64 index, procalcitonin, and C-reactive protein for early sepsis in hematological patients

BACKGROUND

Patients with hematological diseases are immunosuppressed due to various factors, including the disease itself and treatments, such as chemotherapy and immunotherapy, and are susceptible to infection. Infections in these patients often progress rapidly to sepsis, which is life-threatening.

AIM

To evaluate the diagnostic efficacy of the neutrophil CD64 (nCD64) index, compared to procalcitonin (PCT) and high-sensitivity C-reactive protein (hs-CRP), for the identification of early sepsis in patients with hematological diseases.

METHODS

This was a prospective analysis of patients with hematological diseases treated at the Fuxing Hospital affiliated with Capital Medical University, between March 2014 and December 2018. The nCD64 index was quantified by flow cytometry and the Leuko64 assay software. The factors which may affect the nCD64 index levels were compared between patients with different infection statuses (local infection, sepsis, and no infection), and the control group and the nCD64 index levels were compared among the groups. The diagnostic efficacy of the nCD64 index, PCT, and hs-CRP for early sepsis was evaluated among patients with hematological diseases.

RESULTS

A total of 207 patients with hematological diseases (non-infected group, n = 50; locally infected group, n = 67; sepsis group, n = 90) and 26 healthy volunteers were analyzed. According to the absolute neutrophil count (ANC), patients with hematological diseases without infection were divided into the normal ANC, ANC reduced, and ANC deficiency groups. There was no statistically significant difference in the nCD64 index between these three groups (P = 0.586). However, there was a difference in the nCD64 index among the non-infected (0.74 ± 0.26), locally infected (1.47 ± 1.10), and sepsis (2.62 ± 1.60) groups (P < 0.001). The area under the diagnosis curve of the nCD64 index, evaluated as the difference between the sepsis and locally infected group, 0.777, which was higher than for PCT (0.735) and hs-CRP (0.670). The positive and negative likelihood ratios were also better for the nCD64 index than either PCT and hs-CRP.

CONCLUSION

Our results indicate the usefulness of the nCD64 index as an inflammatory marker of early sepsis in hematological patients.

Flow cytometric assessment of monocyte activation markers and circulating endothelial cells in patients with localized or metastatic breast cancer

BACKGROUND

Monocyte activation in cancer patients may be reflective of anticancer activity. However, studies indicate that recruitment of macrophages can actually promote tumor growth and angiogenesis. Assessment of other microenvironmental cells such as circulating endothelial cells (CECs) may provide additional information regarding disease progression. The objective of this study was to assess monocyte activation and CECs in breast cancer patients and determine the potential clinical relevance during disease progression.

METHODS

Patients (n = 41) with localized or metastatic breast cancer who were not currently receiving treatment were eligible for study inclusion. Peripheral blood was collected and analyzed by flow cytometry for monocyte activation (Leuko64 assay kit), and for CECs (CD146(+)CD45(-) phenotype).

RESULTS

Metastatic breast cancer patients demonstrated a higher monocyte CD64 index relative to normal donors and localized breast cancer patients (P < 0.05). Furthermore, breast cancer patients had a lower monocyte CD163 index relative to normal donors (P = 0.008). Localized breast cancer patients demonstrated higher levels of CD146(+)CD45(-) cells CECs relative to metastatic breast cancer patients and normal donors. Within the localized breast cancer population, levels of CD146(+)CD45(-) cells increased with disease stage (P < 0.05).

CONCLUSIONS

These results suggest that monocyte activation and CECs may play a role in breast cancer progression. We speculate that monocyte activation may reflect a reaction to metastatic cells and/or response to tissue damage caused by metastatic growth in distant organs. Furthermore, the observation that CECs increase with disease stage in localized breast cancer suggests that CECs could be a useful surrogate marker for disease progression in this patient population.

Improved diagnostic approaches to infection/sepsis detection

Sepsis is a major healthcare problem from the perspective of mortality and economics. Advances in diagnostic detection of infection and sepsis have been slow, but recent advances in both soluble biomarker detection and quantitative cellular measurements promise the availability of improved diagnostic techniques. Though the promise of cytokine measurements reaching clinical practice have not matured, procalcitonin levels are currently available in many countries and appear to offer enhanced diagnostic distinction between bacterial and viral etiologies. Cellular diagnostics is poised to enter clinical laboratory practice in the form of neutrophil CD64 measurements, which offer superior sensitivity and specificity to conventional laboratory assessment of sepsis. Neutrophil CD64 expression is negligible in the healthy state. However, it increases as part of the systemic response to severe infection or sepsis. The combination of cellular proteomics, as in the case of neutrophil CD64 quantification, and selected soluble biomarkers of the inflammatory response, such as procalcitonin or triggering receptor expressed on myeloid cells (TREM)-1, is predicted to remove the current subjectivity and uncertainty in the diagnosis and therapeutic monitoring of infection and sepsis.

Increased CD11b neutrophil expression in Budd-Chiari syndrome or portal vein thrombosis secondary to polycythaemia vera

Budd-Chiari syndrome and portal vein thrombosis (BCS/PVT) are frequently associated with polycythaemia vera (PV). In an attempt to elucidate the mechanisms of BCS/PVT secondary to PV (T-PV), CD11b neutrophil expression, neutrophil oxidative burst and platelet-neutrophil complexes (PNC) were assessed in 17 such patients. Three groups served as controls: BCS/PVT not secondary to PV (T-nPV; n = 20), PV without thrombosis (PV-nT; n = 16), and healthy controls (HC; n = 20). Baseline CD11b expression (in mean fluorescence intensity units) was 101 [95% confidence interval (CI): 79-128] in T-PV patients, versus 25 (95% CI: 18-35) in T-nPV, 59 (95% CI: 43-80) in PV-nT, and 34 (95% CI: 25-48) in HC (P < 0.001). After N-formyl-L-methionyl-L-leucyl-L-phenylalanine activation, T-PV patients also showed higher CD11b values: 190 (95% CI: 151-238), versus 55 (95% CI: 41-72) in T-nPV, 111 (95% CI: 81-153) in PV-nT, and 77 (95% CI: 63-95) in HC (P < 0.001). In BCS/PVT, CD11b neutrophil expression had 90% specificity and 100% sensitivity for the association with PV. Finally, PV patients had higher oxidative burst and PNC than T-nPV patients or HC (P < 0.05). These results support a role for neutrophils in BCS/PVT secondary to PV and indicate that neutrophil CD11b expression could be of use for PV screening in BCS/PVT patients.

Abnormalities of cytokine receptor signalling contributing to diseases of red blood cell production

The production of erythroid cells is a dynamic and exquisitely regulated process. The mature red cell is only the final phase of a complex but orderly series of genetic events that are initiated at the time a multipotent stem cell becomes committed to expressing the erythroid programme. Aberrations either in the intrinsic generation and/or amplification of functional erythroid cells or in the regulatory influences of microenvironment or cytokines form the basis for a number of blood diseases. In this review we focus upon abnormalities in red blood cell production and discuss how alterations in cytokine regulation of red blood cell production may contribute to these disease processes. We discuss clinical states in which blood red cell numbers are altered, including primary familial and congenital polycythaemia, the myeloproliferative disorder polycythaemia vera, erythroleukaemia, and Diamond-Blackfan anaemia. These disorders are briefly described and evidence supporting a potential role of specific cytokine receptor signalling defects as contributing to these phenotypes is discussed.

Pathogenesis of polycythaemia vera

Polycythaemia vera (PV) is thought to result from clonal expansion of a transformed multipotent stem cell. Progenitors from patients with PV display abnormal responses to several growth factors, suggesting the presence of a defect in a signalling pathway common to different growth factors. A number of approaches are now focused on defining the molecular lesion or lesions. Identification of causal genes will be of considerable interest both to clinicians, who currently lack a specific and sensitive diagnostic test, and to scientists interested in fundamental issues of stem cell behaviour.