Altered leucocyte progenitor profile in human bone marrow from patients with major trauma during the recovery phase

Murine Myeloid Progenitors Attenuate Immune Dysfunction Induced by Hemorrhagic Shock

Hemorrhagic shock induces an aberrant immune response characterized by simultaneous induction of a proinflammatory state and impaired host defenses. The objective of this study was to evaluate the impact of conditionally immortalized neutrophil progenitors (NPs) on this aberrant immune response. We employed a mouse model of hemorrhagic shock, followed by the adoptive transfer of NPs and subsequent inoculation of Staphylococcus aureus to induce pneumonia. We observed that transplant of NPs decreases the proportion of host neutrophils that express programmed death ligand 1 and intercellular adhesion molecule 1 in the context of prior hemorrhage. Following hemorrhage, NP transplant decreased proinflammatory cytokines in the lungs, increased neutrophil migration into the airspaces, and enhanced bacterial clearance. Further, hemorrhagic shock improved NP engraftment in the bone marrow. These results suggest that NPs hold the potential for use as a cellular therapy in the treatment and prevention of secondary infection following hemorrhagic shock.

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Myeloid progenitors restore a competent inflammatory response to pneumonia

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Progenitor transplantation promotes clearance of secondary S. aureus pneumonia

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Hemorrhagic shock enhances engraftment of transplanted myeloid progenitors

Flow Cytometric Analysis of Hematopoietic Populations in Rat Bone Marrow. Impact of Trauma and Hemorrhagic Shock

Severe injury and hemorrhagic shock (HS) result in multiple changes to hematopoietic differentiation, which contribute to the development of immunosuppression and multiple organ failure (MOF). Understanding the changes that take place during the acute injury phase may help predict which patients will develop MOF and provide potential targets for therapy. Obtaining bone marrow from humans during the acute injury phase is difficult so published data are largely derived from peripheral blood samples, which infer bone marrow changes that reflect the sustained inflammatory response. This preliminary and opportunistic study investigated leucopoietic changes in rat bone marrow 6 h following traumatic injury and HS. Terminally anesthetized male Porton Wistar rats were allocated randomly to receive a sham operation (cannulation with no injury) or femoral fracture and HS. Bone marrow cells were flushed from rat femurs and immunophenotypically stained with specific antibody panels for lymphoid (CD45R, CD127, CD90, and IgM) or myeloid (CD11b, CD45, and RP-1) lineages. Subsequently, cell populations were fluorescence-activated cell sorted for morphological assessment. Stage-specific cell populations were identified using a limited number of antibodies, and leucopoietic changes were determined 6 h following trauma and HS. Myeloid subpopulations could be identified by varying levels CD11b expression, CD45, and RP-1. Trauma and HS resulted in a significant reduction in total CD11b + myeloid cells including both immature (RP-1(-)) and mature (RP-1+) granulocytes. Multiple B-cell lymphoid subsets were identified. The total percentage of CD90+ subsets remained unchanged following trauma and HS, but there was a reduction in the numbers of maturing CD90(-) cells suggesting movement into the periphery. © 2019 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.

Giant adrenal myelolipoma: when trauma and oncology collide

Three patients presented some decades after severe traumatic injury with atypical bowel symptoms which were caused by a giant myelolipoma of the adrenal gland. The aetiology of this rare, benign and generally asymptomatic tumour is virtually unknown at present and several hypotheses have been devised. This report describes a possible association between high-energy trauma and the development of giant myelolipomas, further contributing to the hypothesis that severe systemic stress could be an aetiological factor in the development of an adrenal myelolipoma.

Risk of infection and sepsis in severely injured patients related to single nucleotide polymorphisms in the lectin pathway

BACKGROUND

Infectious complications remain a serious threat to patients with multiple trauma. Susceptibility and response to infection is, in part, heritable. The lectin pathway plays a major role in innate immunity. The aim of this study was to assess whether single nucleotide polymorphisms (SNPs) in three key genes within the lectin pathway affect susceptibility to infectious complications in severely injured patients.

METHODS

A prospective cohort of severely injured patients admitted to a level I trauma centre between January 2008 and April 2011 were genotyped for SNPs in MBL2 (mannose-binding lectin 2), MASP2 (MBL-associated serine protease 2) and FCN2 (ficolin 2). Association of genotype with prevalence of positive culture findings and infection was tested by χ(2) and logistic regression analysis.

RESULTS

A total of 219 patients were included, of whom 112 (51·1 per cent) developed a positive culture from sputum, wounds, blood or urine. A systemic inflammatory response syndrome (SIRS) developed in 139 patients (63·5 per cent), sepsis in 79 (36·1 per cent) and septic shock in 37 (16·9 per cent). Patients with a MBL2 exon 1 variant allele were more prone to positive wound cultures (odds ratio (OR) 2·51, 95 per cent confidence interval 1·12 to 5·62; P = 0·025). A MASP2 Y371D DD genotype predisposed to SIRS (OR 4·78, 1·06 to 21·59; P = 0·042) and septic shock (OR 2·53, 1·12 to 4·33; P = 0·003). A FCN2 A258S AS genotype predisposed to positive wound cultures (OR 3·37, 1·45 to 7·85; P = 0·005) and septic shock (OR 2·18, 1·30 to 4·78; P = 0·011).

CONCLUSION

Severely injured patients with SNPs in MBL2, MASP2 Y371D and FCN2 A258S of the lectin pathway of complement activation are significantly more susceptible to positive culture findings, and to infectious complications, SIRS and septic shock than patients with a wildtype genotype.

Surgery, wound healing, and metastasis: recent insights and clinical implications

BACKGROUND

Surgery-induced acceleration of tumour growth has been observed since several centuries.

METHODS

We reviewed recent insights from in vitro data, animal experimentation, and clinical studies on how surgery-induced wound healing or resection of a primary cancer influences the tumour-host ecosystem in patients harbouring minimal residual or metastatic disease.

RESULTS

Most of the growth factors, chemokines, and cytokines orchestrating surgical wound healing promote tumour growth, invasion, or angiogenesis. In addition, resection of a primary tumour may accelerate synchronous metastatic growth. In the clinical setting, indirect evidence supports the relevance of the above findings. Randomized clinical trials are underway comparing resection versus observation in metastatic breast and colon cancer with asymptomatic primary tumours.

CONCLUSIONS

In depth knowledge of how surgical intervention alters the tumour-host-metastasis communicating ecosystems could have important implications for clinical decision making in patients with synchronous metastatic disease and for the design and timing of multimodality treatment strategies.