# Clusterin and pentraxin 3 are markers of severity during febrile neutropenia in adults with haematological malignancies receiving intensive chemotherapy

Coralie Mallebranche, Carole Mosnier, Corentin Orvain, Jérémie Riou, Sylvain

Thepot, Pascale Pignon, Simon Blanchard, Nathalie Tortevoie, Isabelle

Pellier, Mathilde Hunault-Berger, et al.

► To cite this version:

Coralie Mallebranche, Carole Mosnier, Corentin Orvain, Jérémie Riou, Sylvain Thepot, et al. Clusterin and pentraxin 3 are markers of severity during febrile neutropenia in adults with haematological malignancies receiving intensive chemotherapy. British Journal of Haematology, 2025, 207 (3), pp.780-788. 10.1111/bjh.70002. inserm-05467931

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ORIGINAL PAPER

Biology and Translational Science

# Clusterin and pentraxin 3 are markers of severity during febrile neutropenia in adults with haematological malignancies receiving intensive chemotherapy

BJHaem
BRITISH JOURNAL OF HAEMATOLOGY

Coralie Mallebranche<fnref n="1" />,<fnref n="2" /> ID

Carole Mosnier<fnref n="1" />,<fnref n="3" />

Corentin Orvain<fnref n="1" />,<fnref n="3" />,<fnref n="4" /> ID

Jérémie Riou<fnref n="5" />

Sylvain Thepot<fnref n="1" />,<fnref n="3" />,<fnref n="4" />

Pascale Pignon<fnref n="1" />

Simon Blanchard<fnref n="1" />,<fnref n="6" />

Nathalie Tortevoie<fnref n="1" />

Isabelle Pellier<fnref n="1" />,<fnref n="2" />

Mathilde Hunault-Berger<fnref n="1" />,<fnref n="3" />,<fnref n="4" />

Pascale Jeannin<fnref n="1" />,<fnref n="6" />

Yves Delneste<fnref n="1" />

Aline Schmidt-Tanguy<fnref n="1" />,<fnref n="3" />,<fnref n="4" />

Céline Beauvillain<fnref n="1" />,<fnref n="6" />

**Correspondence**

Coralie Mallebranche, Immuno-Hemato-
Oncology Unit, CHU d'Angers, 4 rue Larrey,
Angers 49100, France.

Email: coralie.mallebranche@chu-angers.fr

**Funding information**

Fondation pour la Recherche Médicale;
Angers University Hospital

**Summary**

The identification of predictive biomarkers of severity can improve patient management because febrile neutropenia can be associated with significant morbidity and mortality. We prospectively studied pentraxin 3 (PTX3), a soluble innate immunity receptor, and clusterin (CLU), a chaperone protein that binds extracellular histones during sepsis, in patients experiencing febrile neutropenia after intensive treatment for haematological malignancies. One hundred and forty-three adult patients were included, with 158 episodes of neutropenia analysed. Febrile neutropenia was observed in 119 patients (75%), including 62 without sepsis (group 1; 53%), 42 with sepsis (group 2; 35%) and 14 with severe sepsis/septic shock (group 3; 12%) (missing data, MD): (1) Among these patients, 94 patients had a quick Sequencial Organ Failure Assessment score (qSOFA) <2 (84%) and 18 had qSOFA ≥2 (16%) (MD: 7). PTX3 levels increased significantly more in group 3 than in group 1 (p = 0.009). CLU levels tended to decrease after fever more in patients with qSOFA ≥2 than in those with qSOFA <2 and more in patients in group 3 than in group 1 but without a significant difference. PTX3 and CLU could be biomarkers of severity in patients with febrile neutropenia in adults. Their use to tailor the initial management of febrile neutropenia should be prospectively evaluated.

**KEYWORDS**

infection, leukemia, neutropenia, sepsis

INTRODUCTION

Febrile neutropenia (FN) is a frequent complication in pa-
tients with haematological malignancies receiving inten-
sive chemotherapy treatments and is often due to bacterial

or fungal infections that can cause sepsis or septic shock.<fnref n="1" />,<fnref n="2" />
The risk of mortality after septic shock in these patients
reaches 40%–50%.<fnref n="3" />,<fnref n="4" /> Although the use of empirical antibi-
otics greatly reduces mortality, it remains around 10%.<fnref n="1" /> Few
specific biomarkers are available to quickly predict the type

**Abbreviations:** ALL, acute lymphoid leukaemia; AML, acute myeloid leukaemia; CLU, clusterin; CRP, C-reactive protein; DAMP, damage-associated molecular patterns; FN, febrile neutropenia; HCT, haematopoietic cell transplantation; PRR, pattern recognition receptors; PTX3, pentraxin 3.

Coralie Mallebranche and Carole Mosnier contributed equally as co-first authors.

Aline Schmidt-Tanguy and Céline Beauvillain contributed equally as co-last authors.

This is an open access article under the terms of the [Creative Commons Attribution License](https://creativecommons.org/licenses/by/4.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

© 2025 The Author(s). *British Journal of Haematology* published by British Society for Haematology and John Wiley & Sons Ltd.

<footnote n="1">¹Université Angers, Université de Nantes,
CHU Angers, Inserm, CNRS, CRCI2NA, SFR
ICAT, Angers, France</footnote>

<footnote n="2">²Unité d'onco-Immuno-hémato pédiatrique,
CHU d'Angers, Angers, France</footnote>

<footnote n="3">³Service Des Maladies du Sang, CHU Angers,
Angers, France</footnote>

<footnote n="4">⁴Fédération Hospitalo-Universitaire 'Grand-Ouest Acute Leukemia' (FHU-GOAL),
Angers, France</footnote>

<footnote n="5">⁵Département de Biostatistiques et de
Méthodologie, CHU Angers, Angers, France</footnote>

<footnote n="6">⁶Laboratoire d'Immunologie et Allergologie,
CHU d'Angers, Angers, France</footnote>
of pathogen and the severity of FN and to adapt patient care. The most widely studied and validated are C-reactive protein (CRP) and procalcitonin.⁵

Pattern recognition receptors (PRR) are a diverse group of cellular or soluble sensors belonging to the innate immune system. Soluble PRR include, among others, complement components, surfactant proteins, mannose binding lectin, ficolins and pentraxins.⁶ The roles of PRR are to recognize pathogen-associated molecular patterns and damage-associated molecular patterns (DAMP); activate complement; promote phagocytosis through opsonization; and regulate inflammation.⁶ In addition to CRP, PRR include pentraxin 3 (PTX3), a long pentraxin produced by endothelial and phagocytic cells such as neutrophils.⁷,⁸ Both CRP and PTX3 levels increase during infection, particularly bacterial infections, and may be useful in predicting sepsis.⁹⁻¹² Since PTX3 is released earlier than CRP during inflammation, PTX3 is an attractive biomarker for patients with neutropenia that require prompt and appropriate care.¹³⁻¹⁵

Clusterin (CLU) is a multifunctional protein with multiple properties that act as an apolipoprotein, a complement regulator and an extracellular chaperone.¹⁶ As a chaperone, CLU stabilizes a wide range of proteins and prevents the formation of toxic aggregates,¹⁷ thereby promoting their clearance. These properties extend to toxic proteins, such as certain DAMP, giving CLU a role in tissue protection by limiting apoptosis and necrosis, attenuating inflammation and reducing autoimmune responses.¹⁸⁻²⁰ Recently, we demonstrated that CLU can bind to extracellular histones and neutralizes their cytotoxic effects.²¹ Following severe organ injury resulting in cell death or during NETosis, histones can be released, causing endothelial damage and promoting inflammatory response and thrombosis. During sepsis, serum CLU levels decrease, with a prolonged decrease associated with mortality.

In FN, biomarkers are needed to evaluate the severity of sepsis during bacterial infections, as well as in other types of infection (viral or fungal). These biomarkers should reflect tissue injury, enabling the selection of the most appropriate treatment or medical unit for the patient. No previous study has explored the variation of CLU in neutropenic patients. The aim of our study is to describe and evaluate the variations in PTX3 and CLU levels during chemotherapy-induced FN, with a particular focus on assessing whether these soluble innate proteins could be valuable biomarkers.

# PATIENTS AND METHODS

## Study cohort and ethical considerations

This prospective study included adult patients aged ≥18 years hospitalized at Angers University Hospital between March 2014 and October 2017 for acute lymphoid leukaemia (ALL) induction, acute myeloid leukaemia (AML) induction or consolidation or high-dose chemotherapy with autologous haematopoietic cell transplantation (HCT) as consolidation treatment for multiple myeloma or lymphoma. Patients with

acute promyelocytic leukaemia were not included. The same patient may be included several times during successive courses of chemotherapy. This study was conducted in accordance with the Declaration of Helsinki and its later amendments. Written informed consent was obtained from all patients.

## Definitions

Neutropenia is defined as a neutrophil count ≤0.5 G/L. Fever is defined as a body temperature ≥38.3°C once or ≥38°C at least twice within 1 h.²²

Patient data were classified according to two different classifications: recommendations from the 2001 International Sepsis Definitions Conference²³ according to the severity of the infectious event and according to the quick Sequential Organ Failure Assessment score (qSOFA) at the onset of fever.²⁴ The first classification divided into three ‘fever groups’: ‘on-complicated FN—without sepsis’ (group 1), including patients with FN and systemic inflammatory response syndrome (SIRS); ‘Sepsis’ (group 2); and ‘Severe sepsis’ (group 3) including patients with severe sepsis or septic shock. Sepsis was defined as SIRS with a documented or suspected infection, severe sepsis as sepsis with at least one organ injury and septic shock as severe sepsis with ongoing arterial hypotension despite adequate fluid resuscitation and requiring the use of vasopressor therapy. Concerning qSOFA, the presence of at least two criteria was considered a poor prognostic factor, and patients were classified into two groups: qSOFA <2 and qSOFA ≥2.

## Biological analyses

Blood samples were drawn just before the start of the chemotherapy, during neutropenia (without fever), at the onset of fever (designated as day 0 or D0) and 48 h after the onset of fever (day 2 or D2). Serum samples were frozen at -80°C until use. PTX3 levels were evaluated using a homemade ELISA assay, including an anti-human PTX3 monoclonal antibody (MNB4 clone) as capture Ab (provided by Mantovani's lab) and a polyclonal PTX3 antibody as detection antibody.⁸,²⁵ Human CLU was quantified on serum using a commercial ELISA kit (Human CLU Quantikine R&D® Systems, Minneapolis, MN, USA), according to the manufacturer's recommendations. IL-6, IL-8, TNFα and IL-1β were quantified using a magnetic Luminex® assay (Bioplex200®, BioRad, Hercules, CA, USA), according to the manufacturer's recommendations.

## Statistical analysis

Categorical and continuous variables were compared by $\chi^2$ or Fisher exact tests and by the Mann-Whitney test respectively. Multiple comparison analyses used the Kruskal-Wallis test. To study associations between qSOFA or Fever Group variables and the trajectory of biomarkers, a linear mixed model was computed. The fixed effects chosen for the analyses
were time and time² to capture the parabolic trajectories of biomarkers of interest. We also added a random intercept to the model to capture inter- and intra-individual variability. Statistical analyses were performed with GraphPad Prism (version 10.1) and R software (version 3.6.1).²⁶

# RESULTS

## Characteristics of patients and of episodes of FN

One hundred and forty-two patients were screened between March 2014 and October 2017 for a total of 169 events evaluated, of which 158 were included and analysed (Figure 1). Fourteen patients were included twice during different courses and one patient was included three times. Median age at diagnosis was 55 years [min-max: 18-74]. Median duration of neutropenia was 9 days [min-max: 2-68]. One hundred and nineteen cases (75%) progressed to FN. FN was more frequent during treatment for lymphoma ($p=0.006$) and less frequent during treatment of ALL ($p<10^{-4}$) (Table 1).

Sixty-two events (52%) were FN without sepsis (group 1), while 42 (35%) were a sepsis (group 2) and 14 (12%) were severe sepsis (8 events) or septic shock (6 events) (group 3) (Figure 1; Table S1). Eighteen FN events (16%; missing data [MD]: 7) were classified with a qSOFA score ≥2 (Figure 1; Table S2). Patients in groups 2 and 3 had more bacterial ($p<10^{-4}$) and fungal ($p<10^{-4}$) carriages than patients in group 1. As expected, they developed significantly more bacteraemia ($p<10^{-4}$) than patients from group 1. Patients with a qSOFA score ≥2 also had more fungal documentations ($p<10^{-4}$) and developed more fungal infection than those with a qSOFA score <2 ($p=0.02$). Three patients died during FN. All these patients were included in group 3 and had a qSOFA score ≥2. Group 3 ($p<10^{-4}$) and a qSOFA score ≥2 ($p=0.004$) were both associated with a higher risk of death.

Depending on the classification used, the proportion of 'high-risk' events thus varied, from 11% considering group 3 to 16% for patients with qSOFA ≥2 (Figure 1). Eleven events were classified in both 'high-risk' groups (group 3 + qSOFA ≥2), while discrepancies were found for eight events: two patients classified as group 3 (for severe sepsis and septic shock) did not have a qSOFA ≥2, and six patients with a qSOFA ≥2 did not have group 3 criteria (three SIRS without sepsis and three non-severe sepsis). Among the three patients in group 1 with a qSOFA ≥2, two had hypotension associated with mild confusion (Glasgow score=14) and one had neurological and respiratory signs considered to be side effects of oxycodone.

## Variations in PTX3 and CLU levels according to the severity of the FN episode

At D0 (day of fever onset), serum PTX3 levels were higher in patients with severe sepsis than in patients with fever

without sepsis ($p=0.02$) (Table S1). Longitudinal analysis of all available samples showed significant variations in PTX3 levels over time ($p=0.01$). Moreover, these variations differed significantly according to the sepsis severity groups studied, with a significantly higher elevation of PTX3 levels in group 3 than in group 1 ($p=0.009$) (Figure 2A). CLU levels also varied over time ($<10^{-4}$), but without significant differences between the three groups (Figure 2C). Longitudinal analysis of Interleukine 6 (IL-6) and Tumor Necrosis Factor alpha (TNFα) levels showed the same trends as PTX3, with higher levels from D0 onwards in group 3 (respectively, $p=0.02$; $p=0.008$) (Figure S1A,E). No significant difference was found between groups for IL-8 and CRP (Figure S1C,G). White blood cells (WBCs) did not appear to differ between groups (non-significant) (not shown). PTX3 and pro-inflammatory cytokine levels increased according to sepsis severity in patients with FN.

At D0, PTX3 (Figure 2B) and cytokines (IL-6, Interleukine 8 (IL-8), TNFα) (Figure S1B,D,F) showed no significant differences in either levels or trajectory model when classified according to qSOFA. The longitudinal trajectory model tended towards a steeper decrease in CLU level in patients with a qSOFA score ≥2; however, it was non-significant (Figure 2D). CLU levels tended to decrease with increasing qSOFA scores in patients with FN, but none of the parameters investigated in our study were significantly different according to qSOFA score.

No association was found between CLU or PTX3 and mortality, but the number of cases was low (three patients).

## Variations in PTX3 and CLU levels according to type of infection

At D0, PTX3 levels were significantly higher in patients with an identified bacterial infection (0.98 ng/mL) than in patients without identified bacterial infection (0.67 ng/mL) ($p<0.05$). No significant difference was found between patients with or without bacteraemia nor between patients with or without fungal infection. No significant difference was found in CLU level according to the type of infection.

Elevated PTX3 levels appeared to be associated with bacterial infection during FN.

## Correlation of CLU and PTX3 with inflammatory markers

Finally, we assessed the correlation between CLU, PTX3, and pro-inflammatory cytokine levels. At D0, CLU levels were statistically negatively correlated to PTX3, IL-6, TNFα and CRP levels (Figure 3), while PTX3 levels were positively correlated with IL-6, IL-8, TNFα and CRP levels (Figure S2). These observations confirm that the inflammatory response during severe infections in patients with FN is associated with an increase in serum PTX3 levels and a decrease in serum CLU levels.
<figure><img src="image_2.png" /><figcaption>**FIG URE 1** (A) Flow chart illustrating the process of data analysis in the study. (B) Distribution of patients by classification. Numbers in each square indicate the number of participants at each step. For six patients from group 1 and one patient from group 2, data were not available for qSOFA classification. AML, acute myeloid leukaemia; MD, missing data; qSOFA, quick SOFA score; w/o, without.</figcaption></figure>

DISCUSSION

In this study, we evaluated variations of PTX3 and CLU
levels in patients with FN after chemotherapy for haema-
tological malignancies. PTX3 levels increased in patients
experiencing severe sepsis, irrespective of qSOFA, were
associated with bacterial infections, and correlated with
pro-inflammatory cytokines and CRP. CLU levels tend to
decrease in patients with severe sepsis and qSOFA ≥2 and
correlated inversely with pro-inflammatory cytokines (IL-6,
TNFα) and inflammatory markers (CRP).

Patients included in our study had initial characteristics
similar to those in recent studies, particularly regarding the

type of disease.¹,²⁷ Notably, the number of severe events and
deaths attributable to infection was particularly low in our
study in comparison to previous studies,¹,⁴ but nevertheless
close to more recently published data.²⁷ Severe infectious
events have been steadily decreasing as supportive care in
haematology has progressed, alongside improved prognosis
due to better disease management and new therapies. With
the enhancement of haematology-related prognosis, it is be-
coming far less tolerable for deaths to be due to iatrogenesis.
Therefore, studies evaluating early markers of severity are es-
sential, as the time to initiate appropriate treatment is crucial
in these pathologies.¹ The parallel aim is to identify patients
with lower risk of complications, even in populations usually
<table><caption>TABLE 1 Patient characteristics by febrile neutropenia occurrence.</caption><thead><tr><th>Clinical characteristics***</th><th>Non-febrile neutropenia</th><th>Febrile neutropenia</th><th>Total</th><th>p-value</th></tr></thead><tbody><tr><td></td><td>39 (25)</td><td>119 (75)</td><td>158</td><td></td></tr><tr><td>Sex, n (%)</td><td></td><td></td><td></td><td></td></tr><tr><td>Male</td><td>24 (62)</td><td>72 (61)</td><td>96 (61)</td><td>0.99**</td></tr><tr><td>Female</td><td>15 (38)</td><td>47 (39)</td><td>62 (39)</td><td></td></tr><tr><td>Median age at diagnosis (years) [Min-Max]</td><td>54 [20; 74]</td><td>56 [18; 71]</td><td>55</td><td>0.37***</td></tr><tr><td>Type of disease and treatment, n (%)</td><td></td><td></td><td></td><td></td></tr><tr><td>AML</td><td>14 (36)</td><td>49 (41)</td><td>63 (40)</td><td><strong>&lt;10<sup>-4</sup>*</strong></td></tr><tr><td>ALL</td><td>11 (28)</td><td>5 (4)</td><td>16 (10)</td><td><strong>&lt;10<sup>-4</sup>**</strong></td></tr><tr><td>Lymphoma</td><td>4 (10)</td><td>38 (32)</td><td>42 (27)</td><td><strong>0.006**</strong></td></tr><tr><td>Myeloma</td><td>10 (26)</td><td>27 (23)</td><td>37 (23)</td><td>0.83**</td></tr><tr><td>Type of treatment, n (%)</td><td></td><td></td><td></td><td></td></tr><tr><td>HDC with AHCT</td><td>13 (33)</td><td>68 (57)</td><td>81 (51)</td><td><strong>0.02**</strong></td></tr><tr><td>Median duration of neutropenia (days) [Min-Max]</td><td>7.5 [2; 29]</td><td>10 [3; 68]</td><td>9</td><td>0.12***</td></tr><tr><td>Microbial carriages, n (%)</td><td></td><td></td><td></td><td></td></tr><tr><td>Bacterial</td><td>15 (38)</td><td>61 (51)</td><td>76 (48)</td><td>0.19**</td></tr><tr><td>Fungal</td><td>1 (3)</td><td>11 (9)</td><td>12 (8)</td><td>0.06**</td></tr><tr><td>Infection, n (%)</td><td></td><td></td><td></td><td></td></tr><tr><td>Bacterial</td><td>5 (13)</td><td>43 (36)</td><td>48 (30)</td><td><strong>0.008**</strong></td></tr><tr><td>Including bacteraemia</td><td>3 (7)</td><td>31 (26)</td><td>34 (22)</td><td><strong>0.02**</strong></td></tr><tr><td>Fungal</td><td>1 (3)</td><td>9 (8)</td><td>10 (6)</td><td>0.45**</td></tr><tr><td>Death, n (%)</td><td>—</td><td>3 (3)</td><td>3 (2)</td><td>0.99**</td></tr><tr><td>Biological results (median [IQR])</td><td></td><td></td><td></td><td></td></tr><tr><td>CLU (µg/mL)</td><td></td><td></td><td></td><td></td></tr><tr><td>Inclusion</td><td>276.3 [230; 320]</td><td>238.6 [182; 280]</td><td></td><td><strong>0.003***</strong></td></tr><tr><td>Day of fever</td><td>—</td><td>204.5 [150; 252]</td><td></td><td></td></tr><tr><td>PTX3 (ng/mL)</td><td></td><td></td><td></td><td></td></tr><tr><td>Inclusion</td><td>0.38 [0.18; 0.63]</td><td>0.35 [0.16; 0.61]</td><td></td><td>0.76***</td></tr><tr><td>Day of fever</td><td>—</td><td>0.8 [0.43; 1.5]</td><td></td><td></td></tr></tbody></table>

Note: The initial patient characteristics were retrieved from medical records and categorized based on their 'febrile' status. Categorical variables were compared using $\chi^2$ or Fisher's' exact tests, while continuous variables were assessed using the Mann-Whitney test***. Bold values indicate significant of $p < 0.05$.

Abbreviations: AHCT, autologous haematopoietic cell transplantation; ALL, acute lymphoblastic leukaemia; AML, acute myeloid leukaemia; CLU, clusterin; HDC, high-dose chemotherapy; IQR, interquartile range; n, number of events; PTX3, pentraxin 3.

considered at risk such as those included in our study. This approach could help reduce treatments, thereby improving quality of life and reducing adverse effects. Variations in CLU and PTX3 levels appeared to differ according to classification. Using the 2001 International Sepsis Definition, according to SIRS/Sepsis/Severe sepsis—Septic shock status,²³ PTX3 is significantly higher in patients with severe sepsis or septic shock. With this classification, CLU decreased sharply but not significantly. In contrast, according to the current qSOFA classification,²⁴ used in Sepsis-3 definition proposed in 2016, CLU levels decreased more in patients with qSOFA ≥2, indicating a high risk of sepsis-related mortality, while PTX3 seemed less marked with this classification. Thus, PTX3 and CLU could have distinct purposes in the assessment of FN. Historically, the Sepsis-3 classification was proposed because the previous classification, which used the SIRS notion, was considered to be too sensitive and not

specific enough regarding the infectious origin.²⁸ However, in our study, CLU, which seems more closely associated with qSOFA, appears to be more closely linked to all-cause severity, whereas PTX3 is associated with the 2001 classification and the presence of a confirmed bacterial infection.

PTX3 has been studied as a biomarker in numerous studies on sepsis or septic shock. Our study is the largest cohort to date evaluating PTX3 in FN,¹⁴,¹⁵ and the only one assessing PTX3 according to qSOFA in this context. The role of PTX3 is well established in sepsis due to bacteria, with a predictive value for severe sepsis and mortality consistently demonstrated,⁹⁻¹¹,²⁹ along with a strong correlation between PTX3 levels and SOFA score. Our results confirmed that elevated serum PTX3 levels were significantly associated with sepsis or severe sepsis/septic shock and with bacterial infection. However, we did not find an association between PTX3 levels and the qSOFA score, in contrast to studies conducted
<figure><img src="image_3.png" /><figcaption>**FIG URE 2** Kinetic variation of pentraxin 3 (PTX3) and clusterin (CLU) levels in serum from patients with febrile neutropenia. Day 0 indicates the first day of fever. (A) PTX3 levels (ng/mL) in patients with febrile neutropenia over time (in days) according to the severity of the febrile neutropenia. (B) PTX3 levels (ng/mL) in patient with febrile neutropenia over time (in days) according to Sequential Organ Failure Assessment (SOFA) score. (C) CLU levels (µg/mL) in patient with febrile neutropenia over time (in days) according to the severity of the febrile neutropenia. (D) CLU levels (ng/mL) in patient with febrile neutropenia over time (in days) according to SOFA score. All the results are obtained through a linear mixed model; fixed effects were time and time².</figcaption></figure>

in non-neutropenic populations; thus, PTX3 appears insuf-
ficient to assess the risk of mortality in FN. A potential hy-
pothesis is that PTX3 is mainly synthesized by myeloid cells,⁷
including neutrophils,⁸,²⁵ whose numbers are reduced during
FN. This reduction does not allow an increase in PTX3 pro-
duction to a significant level in this context. Furthermore, the
number of patients with a qSOFA score ≥2 is low in our study,
which may fail to highlight a difference related to this score.
None of the parameters studied were significantly different
according to qSOFA score. Thus, we cannot conclude that
PTX3 is a biomarker of high risk of mortality in patients with
chemotherapy-induced neutropenia, although it remains a
strong marker of severe infections.

Our study is the first study assessing CLU in neutropenic
patients. CLU has been described as associated with infec-
tions since its earliest descriptions. Low circulating CLU lev-
els have been reported in bacterial infections (Streptococcus
pyogenes, Neisseria meningitidis, Streptococcus pneumoniae,
Staphylococcus aureus),³⁰,³¹ as well as in viral infections, such
as dengue virus³² or coronavirus OC43³³ infections. The
mechanisms behind these observations remained unclear until
recent studies highlighted the role of CLU in severe sepsis, its
association with mortality and its potential use as a biomarker
of severity.²¹,³⁴ CLU levels decrease during severe sepsis due to
consumption, including through binding to extracellular his-
tones released during severe inflammation.²¹ In our study, it
<figure><img src="image_4.png" /></figure>

<figure><img src="image_5.png" /></figure>

<figure><img src="image_6.png" /></figure>

<figure><img src="image_7.png" /></figure>

<figure><img src="image_8.png" /></figure>

<figure><img src="image_9.png" /></figure>

**FIG URE 3** Correlation between clusterin (CLU) and pentraxin 3 (PTX3), IL-6, IL-8, TNFα, C-reactive protein (CRP), serum and white blood cell (WBC) levels on the first day of fever (D0). Serum levels are represented on logarithmic scales for both axes. Lines depict non-linear regressions. Correlations are assessed using nonparametric Spearman correlation tests, as the distributions are not Gaussian. 'r' represents Spearman's coefficient. (A) Correlation between CLU and PTX3 levels. (B) Correlation between CLU and IL-6 levels. (C) Correlation between CLU and IL-8 levels. (D) Correlation between CLU and TNFα levels. (E) Correlation between CLU and CRP levels. (F) Correlation between CLU and WBC levels.

was challenging to assess the role of CLU in evaluating mortal-
ity, due to the small number of events. However, CLU levels ap-
peared to decrease more in patients with a high qSOFA, which
is associated with a higher risk of mortality, although these
results were not significant. This suggests that CLU may serve
as a severity biomarker rather than as a specific biomarker of
infection. In addition, CLU is ubiquitous in the human body³⁵
and its synthesis should not be significantly altered by the de-
crease in haematopoietic cells, making it an interesting marker
in haematology patients. However, a probably significant

proportion of the extracellular histones released during severe
infection comes from NETosis. Consequently, the amount of
extracellular histones to be cleared during infection may be
lower in neutropenic patients, who have fewer neutrophils
compared to other patients with severe infections. This could
potentially explain the smaller decrease in CLU levels observed
in this cohort compared to previous studies,²¹ as its chaperone
activity on histones and their scavenging would be less signifi-
cant, even in severe patients. Further studies will be needed to
assess the role of CLU in patients with neutropenia.
CONFLICT OF INTEREST STATEMENT

We have no conflicts of interest to disclose.

DATA AVAILABILITY STATEMENT

The data that support the findings of this study are available
from the corresponding author upon reasonable request.

ETHICS STATEMENT

This study was conducted in accordance with the Declaration
of Helsinki and its later amendments and was approved by
the national committee for the protection of individuals
(CPP).

PATIENT CONSENT STATEMENT

Written informed consent was obtained from all patients.

ORCID

Coralie Mallebranche https://orcid.
org/0000-0002-8385-4057

Corentin Orvain https://orcid.org/0000-0002-8717-0824

REFERENCES

1. Rosa RG, Goldani LZ. Cohort study of the impact of time to antibiotic administration on mortality in patients with febrile neutropenia. Antimicrob Agents Chemother. 2014;58(7):3799-803. https://doi.org/10.1128/AAC.02561-14

2. Erdem H, Kocoglu E, Ankarali H, El-Sokkary R, Hakamifard A, Karaali R, et al. Prospective analysis of febrile neutropenia patients with bacteraemia: the results of an international ID-IRI study. Int J Antimicrob Agents. 2023;62(3):106919. https://doi.org/10.1016/j.ijantimicag.2023.106919

3. Kuderer NM, Dale DC, Crawford J, Cosler LE, Lyman GH. Mortality, morbidity, and cost associated with febrile neutropenia in adult cancer patients. Cancer. 2006;106(10):2258-66. https://doi.org/10.1002/cncr.21847

4. Chumbita M, Puerta-Alcalde P, Gudiol C, Garcia-Pouton N, Laporte-Amargós J, Ladino A, et al. Impact of empirical antibiotic regimens on mortality in neutropenic patients with bloodstream infection presenting with septic shock. Antimicrob Agents Chemother. 2022;66(2):e0174421. https://doi.org/10.1128/AAC.01744-21

5. Jantunen E, Hämäläinen S, Pulkki K, Juutilainen A. Novel biomarkers to identify complicated course of febrile neutropenia in hematological patients receiving intensive chemotherapy. Eur J Haematol. 2024;113(4):392-9. https://doi.org/10.1111/ejh.14264

6. Garlanda C, Bottazzi B, Magrini E, Inforzato A, Mantovani A. PTX3, a humoral pattern recognition molecule, in innate immunity, tissue repair, and cancer. Physiol Rev. 2018;98(2):623-39. https://doi.org/10.1152/physrev.00016.2017

7. Alles VV, Bottazzi B, Peri G, Golay J, Introna M, Mantovani A. Inducible expression of PTX3, a new member of the pentraxin family, in human mononuclear phagocytes. Blood. 1994;84(10):3483-93.

8. Jaillon S, Peri G, Delneste Y, Frémaux I, Doni A, Moalli F, et al. The humoral pattern recognition receptor PTX3 is stored in neutrophil granules and localizes in extracellular traps. J Exp Med. 2007;204(4):793-804. https://doi.org/10.1084/jem.20061301

9. Chen H, Li T, Yan S, Liu M, Liu K, Zhang H, et al. Pentraxin-3 is a strong biomarker of sepsis severity identification and predictor of 90-day mortality in intensive care units via sepsis 3.0 definitions. Diagnostics. 2021;11(10):1906. https://doi.org/10.3390/diagnostics11101906

10. Davoudian S, Piovani D, Desai A, Mapelli SN, Leone R, Sironi M, et al. A cytokine/PTX3 prognostic index as a predictor of mortality in sepsis. Front Immunol. 2022;13:979232. https://doi.org/10.3389/fimmu.2022.979232

Few severe events were reported, and even less post-
infectious deaths, reflecting the improvement in supportive
care in haematological malignancies. While this is obviously
positive for patients, it reduced the power of our results, as
these outcomes were not anticipated due to their absence in
previous studies. Consequently, none of the markers eval-
uated were significantly affected by qSOFA, including pro-
inflammatory cytokines. CLU levels seemed to be most
associated with qSOFA, but this association was not signifi-
cant. Another challenge was compliance with the study sched-
ule. Many patients could not be sampled at the strict D0 and
D2 dates, as planned in the protocol, necessitating the use of
trajectory analyses to study all enrolled patients. Additionally,
we encountered changes in scoring system during our study.
The Sepsis-3 classification was proposed after our study
began, which is why we proposed to study both 2001 and 2016
classifications. This classification has been questioned in re-
cent years,³⁶ particularly with regard to the capacity of the
qSOFA as a rapid assessment tool for severity. Other so-called
'Early Warning Scores', such as the NEWS (National Early
Warning Score),³⁷ could be used to identify the risk of mor-
tality at an earlier stage. It appears to be as effective as qSOFA
in assessing mortality risk,³⁸ and further studies are needed to
compare the added value of each.

PTX3 and CLU could therefore be valuable for the early
assessment of patients with FN. PTX3 may be used to eval-
uate sepsis intensity and aetiology, while CLU appears to
be a more appropriate biomarker for mortality risk in this
context. This study should be extended to confirm this hy-
pothesis and possibly develop a score adapted to neutropenic
patients.

AUTHOR CONTRIBUTIONS

Coralie Mallebranche: conceptualization, investigation, visualization, formal analysis, original draft preparation, review and editing. Carole Mosnier: conceptualization, investigation, original draft preparation, review and editing. Corentin Orvain: conceptualization, investigation, review and editing. Jérémie Riou: formal analysis, software, review and editing. Sylvain Thépot: conceptualization, review and editing. Pascale Pignon: investigation, review and editing. Simon Blanchard: investigation, review and editing. Nathalie Tortevoie: investigation, review and editing. Isabelle Pellier: conceptualization, review and editing. Mathilde Hunault-Berger: conceptualization, review and editing. Pascale Jeannin: review and editing. Yves Delneste: conceptualization, review and editing. Aline Schmidt-Tanguy: conceptualization, funding acquisition, investigation, visualization, original draft preparation, review and editing.

FUNDING INFORMATION

This study received a grant from Angers University Hospital.
C.M. obtained a grant from the 'Fondation pour la Recherche
Médicale'.
11. Perez-San Martin S, Suberviola B, Garcia-Unzueta MT, Lavin BA, Campos S, Santibañez M. Prognostic value of plasma pentraxin 3 levels in patients with septic shock admitted to intensive care. PLoS One. 2020;15(12):e0243849. https://doi.org/10.1371/journal.pone.0243849

12. Porte R, Silva-Gomes R, Theroude C, Parente R, Asgari F, Sironi M, et al. Regulation of inflammation and protection against invasive pneumococcal infection by the long pentraxin PTX3. elife. 2023;12:e78601. https://doi.org/10.7554/eLife.78601

13. Al-Ramadi BK, Ellis M, Pasqualini F, Mantovani A. Selective induction of pentraxin 3, a soluble innate immune pattern recognition receptor, in infectious episodes in patients with haematological malignancy. Clin Immunol. 2004;112(3):221-4. https://doi.org/10.1016/j.clim.2004.03.012

14. Vänskä M, Koivula I, Hämäläinen S, Pulkki K, Nousiainen T, Jantunen E, et al. High pentraxin 3 level predicts septic shock and bacteremia at the onset of febrile neutropenia after intensive chemotherapy of hematologic patients. Haematologica. 2011;96(9):1385-9. https://doi.org/10.3324/haematol.2011.044925

15. Juutilainen A, Vänskä M, Pulkki K, Hämäläinen S, Nousiainen T, Jantunen E, et al. Pentraxin 3 predicts complicated course of febrile neutropenia in haematological patients, but the decision level depends on the underlying malignancy. Eur J Haematol. 2011;87(5):441-7. https://doi.org/10.1111/j.1600-0609.2011.01666.x

16. Humphreys DT, Carver JA, Easterbrook-Smith SB, Wilson MR. Clusterin has chaperone-like activity similar to that of small heat shock proteins. J Biol Chem. 1999;274(11):6875-81. https://doi.org/10.1074/jbc.274.11.6875

17. Wyatt AR, Yerbury JJ, Berghofer P, Greguric I, Katsifis A, Dobson CM, et al. Clusterin facilitates in vivo clearance of extracellular misfolded proteins. Cell Mol Life Sci. 2011;68(23):3919-31. https://doi.org/10.1007/s00018-011-0684-8

18. McLaughlin L, Zhu G, Mistry M, Ley-Ebert C, Stuart WD, Florio CJ, et al. Apolipoprotein J/clusterin limits the severity of murine autoimmune myocarditis. J Clin Invest. 2000;106(9):1105-13. https://doi.org/10.1172/JCI9037

19. Systemic lupus erythematosus, a disease associated with low levels of clusterin/apoJ, an antiinflammatory protein. [cited 2024 March 8]. Available from: https://pubmed.ncbi.nlm.nih.gov/10090169/

20. Clusterin facilitates apoptotic cell clearance and prevents apoptotic cell-induced autoimmune responses. [cited 2024 March 8]. Available from: https://pubmed.ncbi.nlm.nih.gov/27148688/

21. Augusto JF, Beauvillain C, Poli C, Paolini L, Tournier I, Pignon P, et al. Clusterin neutralizes the inflammatory and cytotoxic properties of extracellular histones in sepsis. Am J Respir Crit Care Med. 2023;208(2):176-87. https://doi.org/10.1164/rccm.202207-1253OC

22. Villafuerte-Gutierrez P, Villalon L, Losa JE, Henriquez-Camacho C. Treatment of febrile neutropenia and prophylaxis in hematologic malignancies: a critical review and update. Adv Hematol. 2014;2014:986938. https://doi.org/10.1155/2014/986938

23. Levy MM, Fink MP, Marshall JC, Abraham E, Angus D, Cook D, et al. 2001 SCCM/ESICM/ACCP/ATS/SIS international sepsis definitions conference. Crit Care Med. 2003;31(4):1250-6. https://doi.org/10.1097/01.CCM.0000050454.01978.3B

24. Singer M, Deutschman CS, Seymour CW, Shankar-Hari M, Annane D, Bauer M, et al. The third international consensus definitions for sepsis and septic shock (Sepsis-3). JAMA. 2016;315(8):801-10. https://doi.org/10.1001/jama.2016.0287

25. Jaillon S, Jeannin P, Hamon Y, Frémaux I, Doni A, Bottazzi B, et al. Endogenous PTX3 translocates at the membrane of late apoptotic human neutrophils and is involved in their engulfment by macrophages. Cell Death Differ. 2009;16(3):465-74. https://doi.org/10.1038/cdd.2008.173

26. R Core Team. R: A language and environment for statistical computing. Vienna, Austria: R Foundation for Statistical Computing; 2021. Available from: https://www.R-project.org/

27. Verlinden A, Jansens H, Goossens H, Anguille S, Berneman ZN, Schroyens WA, et al. Safety and efficacy of antibiotic de-escalation and discontinuation in high-risk hematological patients with febrile neutropenia: a single-center experience. Open Forum Infect Dis. 2021;9(3):ofab624. https://doi.org/10.1093/ofid/ofab624

28. Vincent JL, Opal SM, Marshall JC, Tracey KJ. Sepsis definitions: time for change. Lancet. 2013;381(9868):774-5. https://doi.org/10.1016/S0140-6736(12)61815-7

29. Lapadula G, Leone R, Bernasconi DP, Biondi A, Rossi E, D'Angiò M, et al. Long pentraxin 3 (PTX3) levels predict death, intubation and thrombotic events among hospitalized patients with COVID-19. Front Immunol. 2022;13:933960. https://doi.org/10.3389/fimmu.2022.933960

30. Hogåsen K, Mollnes TE, Brandtzaeg P. Low levels of vitronectin and clusterin in acute meningococcal disease are closely associated with formation of the terminal-complement complex and the vitronectin-thrombin-antithrombin complex. Infect Immun. 1994;62(11):4874-80.

31. Willems E, Alkema W, Keizer-Garritsen J, Suppers A, van der Flier M, Philipsen RHLA, et al. Biosynthetic homeostasis and resilience of the complement system in health and infectious disease. EBioMedicine. 2019;45:303-13. https://doi.org/10.1016/j.ebiom.2019.06.008

32. Kurosu T, Chaichana P, Yamate M, Anantapreecha S, Ikuta K. Secreted complement regulatory protein clusterin interacts with dengue virus nonstructural protein 1. Biochem Biophys Res Commun. 2007;362(4):1051-6. https://doi.org/10.1016/j.bbrcc.2007.08.137

33. Fox CR, Parks GD. Complement inhibitors vitronectin and Clusterin are recruited from human serum to the surface of coronavirus OC43-infected lung cells through antibody-dependent mechanisms. Viruses. 2021;14(1):29. https://doi.org/10.3390/v14010029

34. Yagmur E, Abu Jhaisha S, Buendgens L, Sapundzhieva N, Brozat JF, Hohlstein P, et al. Clusterin plasma concentrations are decreased in sepsis and inversely correlated with established markers of inflammation. Diagnostics. 2022;12(12):3010. https://doi.org/10.3390/diagnostics12123010

35. Wilson MR, Satapathy S, Jeong S, Fini ME. Clusterin, other extracellular chaperones, and eye disease. Prog Retin Eye Res. 2022;89:101032. https://doi.org/10.1016/j.preteyeres.2021.101032

36. Evans L, Rhodes A, Alhazzani W, Antonelli M, Coopersmith CM, French C, et al. Surviving sepsis campaign: International Guidelines for Management of Sepsis and Septic Shock 2021. Crit Care Med. 2021;49(11):e1063. https://doi.org/10.1097/CCM.00000000000005337

37. Liu VX, Lu Y, Carey KA, Gilbert ER, Afshar M, Akel M, et al. Comparison of early warning scoring systems for hospitalized patients with and without infection at risk for in-hospital mortality and transfer to the intensive care unit. JAMA Netw Open. 2020;3(5):e205191. https://doi.org/10.1001/jamanetworkopen.2020.5191

38. Frairia C, Nicolino B, Secreto C, Messa E, Arrigo G, Busca A, et al. Validation of National Early Warning Score and quick sequential (sepsis-related) organ failure assessment in acute myeloid leukemia patients treated with intensive chemotherapy. Eur J Haematol. 2023;110(6):696-705. https://doi.org/10.1111/ejh.13952

## SUPPORTING INFORMATION

Additional supporting information can be found online in the Supporting Information section at the end of this article.

**How to cite this article:** Mallebranche C, Mosnier C, Orvain C, Riou J, Thepot S, Pignon P, et al. Clusterin and pentraxin 3 are markers of severity during febrile neutropenia in adults with haematological malignancies receiving intensive chemotherapy. Br J Haematol. 2025;207(3):780-788. https://doi.org/10.1111/bjh.70002