The first step in utilizing immune-modulating therapies: immune status determination

Recently, a single center study conducted by Oiva and coworkers and published in Critical Care demonstrated that phospho-specific whole blood flow cytometry could be used to assess activated signaling pathways in leukocytes isolated from pancreatitis patients. The authors demonstrated that this methodology had the potential to determine the current status of a patient's immune state. Although the experimental cohort was clinically homogeneous, the observed data were heterogeneous. Altogether, these results suggest that prior to administering immune-modulatory therapies in inflammatory diseases, it will be beneficial to first determine immune status. Rapid results from whole blood phospho-specific flow cytometry may allow for determination of immune status, improve early diagnosis, and provide a rational basis for immunomodulatory therapies.

become leukopenic and immunosuppressed, they often become susceptible to infections with organisms to which a healthy patient would normally be resistant. Although therapy aimed at blunting the initial overexuberant infl ammation may be benefi cial if applied early, it may also be detrimental by impairing the host's ability to fi ght infection that is a common cause of death in these patients. To complicate the potential use of immune-modulating therapy, infl ammatory and antiinfl ammatory processes can occur along diff erent timelines for the varied leukocyte subsets. For example, during immune response, T lymphocytes might be under going apoptosis while neutrophils are primed to produce reactive oxygen species [4]. Th us, during pro longed pancreatitis, leukocyte subsets may be concur rently exhibiting both pro-and anti-infl ammatory processes.
As noted above, a potential promising therapy of pancreatitis is modulation of the immune response [5]. Th is is a diffi cult undertaking as the host response will be aff ected by a number of variables, including genetic background, co-morbidities, age, gender, and so on [6]. In addition, the patient's immune response will vary during the course of the disease. Th us, what is needed for immunotherapy to be practical is a rapid, robust measure of the host immune system.
In the manuscript published by Oiva and co-workers [1], the authors determined the signaling profi les of circulating leukocytes isolated from pancreatitis patients using phospho-specifi c whole blood fl ow cytometry. Th is is a powerful new technology that allows for simultaneous single-cell determination of leukocyte subsets using cell surface markers as well as intracellular protein phosphory lation [7]. Th is work represents a continuation of work published previously [8]. In this earlier work, Oiva and co-workers demonstrated that stimulated monocytes isolated from patients with acute pancreatitis had decreased phosphorylated Erk 1/2, NF-κB, and STAT1 and 3. Th e authors concluded that these changes could lead to impaired monocyte recruitment as well as increased susceptibility to infections. Here, changes in activated T lymphocyte p38, NF-κB, STAT1 and STAT6 activity was observed that could be interpreted as being

Abstract
Recently, a single center study conducted by Oiva and coworkers and published in Critical Care demonstrated that phospho-specifi c whole blood fl ow cytometry could be used to assess activated signaling pathways in leukocytes isolated from pancreatitis patients. The authors demonstrated that this methodology had the potential to determine the current status of a patient's immune state. Although the experimental cohort was clinically homogeneous, the observed data were heterogeneous. Altogether, these results suggest that prior to administering immune-modulatory therapies in infl ammatory diseases, it will be benefi cial to fi rst determine immune status. Rapid results from whole blood phospho-specifi c fl ow cytometry may allow for determination of immune status, improve early diagnosis, and provide a rational basis for immunomodulatory therapies. pro-or anti-infl ammatory. Interestingly, they determined that patients' lymphocytes exhibited decreased phosphory lated NF-κB and STAT1 and increased phosphorylation of p38 and STAT6, suggesting a transition from a Th 1 to Th 2 phenotype. Additionally, this minimally invasive methodology could be used to generate immune status within 6 hours under ideal conditions. Th us, this methodology represents an essential step prior to targeting the underlying immune response to pancreatitis.
Although beyond the scope of the report, a potentially necessary step after immune status determination, and prior to treatment with infl ammatory altering treatments, would be to fi rst treat the whole blood cells isolated from the patients with the potential therapeutic agent and evaluate the immune eff ector cell response. Phosphospecifi c fl ow cytometry could also be used to determine if the leukocytes responded in a way that would be benefi cial. Th us, the minimally invasive, relatively quick methodology developed in this paper could be utilized to determine immune status as well as provide a method to test potential therapies.
One unavoidable limitation to the report is that the signaling processes were determined using only peripheral leukocytes. A possibility exists that peripheral leukocytes may not respond similarly to ex vivo stimuli as leukocytes isolated from the infl ammatory site(s). When feasible, future studies need to be undertaken to compare the response of peripheral leukocytes to these tissue leukocytes.
Rapid results from whole blood phospho-specifi c fl ow cytometry during pancreatitis will allow for immune status determination, likely improve early diagnosis and provide a rational basis for immune targeting therapies. Altogether, this may signifi cantly infl uence the morbidity and mortality of these patients.

Competing interests
The authors declare that they have no competing interests.