TRANSFUSION PRACTICE: sHLA-I contaminating molecules as novel mechanism of ex vivo/in vitro transcriptional and posttranscriptional modulation of transforming growth factor-β1 in CD8+ T lymphocytes and neutrophils after intravenous immunoglobulin treatmen

A high transfusion burden following an ambulatory-allogeneic hematopoietic cell transplantation using reduced-intensity conditioning is associated with adverse outcomes

OBJECTIVES

Ambulatory allogeneic hematopoietic cell transplantation (allo-HCT) after reduced-intensity conditioning (RIC) is a cost-effective option for hematology patients. Data on the impact of transfusion burden in this setting are scarce; we analyzed this retrospectively.

METHODS

A study of 177 HLA-identical and haploidentical allo-HCT recipients on an outpatient basis was conducted between 2013 and 2019. Packed red blood cell (PRBC) and platelet transfusions were documented from days 0-100 after HCT.

RESULTS

A total of 121 patients (68.4%) required transfusion while 56 (31.6%) did not. In the multivariate analysis, a lower disease-free (DFS) and overall survival (OS) were documented for patients that received ≥9 total blood products (p = 0.018) (p = 0.014), those who required hospitalization (p = 0.001) (p < 0.001), had acute graft-versus-host disease (p = 0.016) (p = 0.004), and a high/very high Disease-Risk-Index (p = 0.002; p = 0.004), respectively. Transfusion of ≥5 PRBC units was associated with a lower OS (p = 0.027). The cumulative incidence of transplant-related mortality at two years for an HLA-identical transplant was 9.5% and for haploidentical, it was 27.1% (p = 0.027); this last group had significantly more transfusion demands than HLA-identical recipients (p = 0.029).

CONCLUSION

Increased blood product utilization is an independent predictor of decreased survival in ambulatory RIC allo-HCT recipients. Further evidence leading to individualized guidelines to transfuse in this complex scenario is needed.

Granulocytes and monocytes apheresis induces upregulation of TGFβ1 in patients with active ulcerative colitis: A possible involvement of soluble HLA-I

Granulocyte and monocyte apheresis has been used in different immune-mediated disorders, mainly inflammatory bowel diseases. The removal of activated leukocytes and several additional immunomodulatory mechanisms have been so far suggested to explain the anti-inflammatory effects of the treatment. Recent data indicate that, during centrifugation based apheresis, sHLA-I adsorbed to plastic circuits is able to induce TGFβ₁ production in activated leukocytes. On these bases, the present study was aimed at analyzing if this model could be applied to a noncentrifugation based apheresis, such as granulocyte and monocyte apheresis. Ten patients with ulcerative colitis were enrolled. Every patient received 5 weekly apheresis treatments. Cellulose acetate beads removed from the column post-GMA were stained by fluorescent anticlass I mAb and examined by fluorescent microscope. Moreover, sFasL plasma concentration, TGFβ₁ plasma levels, and the percentage of TGFβ₁ positive neutrophils were evaluated before and immediately after each single apheresis. Immunofluorescent images revealed a homogeneous layer of a sHLA-I adsorbed to the surface of the beads recovered following the procedure. sFasL plasma concentration progressively increased both following the procedures and during inter-procedure periods. Consistently, also TGFβ₁ plasma levels and the percentage of TGFβ₁ positive neutrophils increased during the procedures with a meaningful relationship with sFasL plasma levels. Taken together, these findings suggest that the immunosuppressive effects attributed to granulocyte and monocyte apheresis might depend, at least in part, on the sensitivity of activated leucocytes to the bioactivity of sHLA-I molecules. J. Clin. Apheresis 32:49-55, 2017. © 2016 Wiley Periodicals, Inc.

Soluble molecules in intravenous immunoglobulin: benefits and limitations

Because of its predominance, the main immunomodulatory function of IVIg is carried out by the IgG molecules; while, based on multiple studies, the immunomodulatory role of other soluble molecules in commercial IVIg products is impossible to ignore. Although the existence of these molecules and their suppressive effects on the immune response may be considered a positive contribution to the treatment of autoimmune disorders, their presence, half-life, accumulation and immunosuppressive actions in immunocompromised patients should be monitored by physicians and manufacturing companies.

Bio-modulators in platelet-rich plasma: a comparison of the amounts in products from healthy donors and patients produced with three different techniques

BACKGROUND

Platelet-rich plasma consists of platelets concentrated in a small volume of plasma and constitutes a reservoir of bio-modulators potentially useful in tissue repair. The amounts of bio-modulators detectable in platelet-rich plasma prepared with various commercial or "in house" methods have been reported, but virtually all the analyses described have been performed on platelet-rich plasma derived from healthy donors. Since leucocyte contamination is technically unavoidable, we investigated whether platelet-rich plasma prepared from patients could contain different amounts of bio-modulators because of a possible activated status of the leucocytes.

MATERIALS AND METHODS

We evaluated platelet-rich plasma prepared with three different techniques (the commercial Vivostat and Biomet recover GPS II systems and an "in house" method) starting from whole blood from healthy donors and patients. Specifically, we compared the levels of sHLA-I, sFasL, platelet-derived growth factor, transforming growth factors-beta and vascular endothelial growth factor in the platelet-rich plasma releasates according to the method of preparation and to the immune system activation status of the subjects.

RESULTS

With the exception of sHLA-I levels, no differences were found in the surrogate indices of lymphocyte activation between healthy donors and patients. No significant differences were found in sHLA-I, sFasL, platelet-derived growth factor, transforming growth factors-beta and vascular endothelial growth factor levels detectable in platelet-rich plasma produced with the three different methods in either healthy donors or patients.

DISCUSSION

On the whole our findings indicate that the overall content of bio-modulators in autologous platelet-rich plasma is not influenced by T-lymphocyte activation status, at least in patients with uncomplicated femoral fractures. The amounts of sFasL and sHLA-I detected in all the platelet-rich plasma releasates studied were very small, far below the amounts detectable in all clinically available blood derivatives and absolutely insufficient to induce sHLA-I and/or sFasL mediated immunomodulation.

Blood transfusions with high levels of contaminating soluble HLA-I correlate with levels of soluble CD8 in recipients' plasma; a new control factor in soluble HLA-I-mediated transfusion-modulated immunomodulation?

BACKGROUND

The cause of transfusion-related immunomodulation (TRIM) has proved tantalisingly elusive. An ever-growing body of evidence indicates that the infusion of large amounts of soluble and cell-associated antigens into a recipient can somehow induce TRIM. One soluble molecule that has been implicated in TRIM is soluble human leucocyte antigen I (sHLA-I). However, patients infused with large amounts of sHLA-I do not always and unambiguously experience TRIM. As soluble CD8 (sCD8) molecules have been shown to capable of binding membrane and soluble HLA-I molecules, we focused on sCD8 as a possible modulator of sHLA-I-mediated TRIM.

MATERIAL AND METHODS

To this aim we compared the up-regulation of circulating sCD8 in plasma from patients suffering from the same pathology, but chronically transfused with two different blood derivatives: pre- and post-storage leucodepleted red blood cells which contain low and high levels of contaminating sHLA-I, respectively.

RESULTS

Significantly larger amounts of sCD8 circulating molecules were detectable in the plasma of patients transfused with post-storage leucodepleted red blood cells whose supernatants contained significantly larger amounts of sHLA-I contaminating molecules.

CONCLUSION

With the limitation of indirect evidence, this report introduces a new facet of the bioactivity of sCD8 as a possible modulator of sHLA-I-mediated TRIM.

Intravenous immunoglobulin G (IVIG) inhibits IL-1- and TNF-α-dependent, but not chemotactic-factor-stimulated, neutrophil transendothelial migration

High-dose intravenous immunoglobulin (IVIG) has anti-inflammatory effects via incompletely understood mechanisms. By investigating whether IVIG might modulate neutrophil (PMN) recruitment, we observed that IVIG dose-dependently inhibited (by 30-50%) PMN transendothelial migration (TEM) across human umbilical vein endothelial cells (EC) stimulated with IL-1α, IL-1β, TNF-α or IL-1β+TNF-α. Inhibition required the presence of IVIG with the responding PMNs, was attributable to the F(ab)(2) portion and was unrelated to putative contaminants in IVIG. IVIG did not inhibit IL-1β- or TNF-α-induced increase of PMN adhesion to EC, nor did it affect C5a- or IL-8-induced PMN TEM across unstimulated EC. Effects of IVIG and F(ab)(2) fragments were not associated with PMN activation, assessed by CD62L shedding, CD11b upregulation or PMN shape. Thus, IVIG selectively inhibits PMN TEM across inflammatory-cytokine-stimulated - but not unstimulated - EC, perhaps contributing to therapeutic benefit in chronic inflammation with minimal impact on chemotactic-factor-induced PMN recruitment during acute infection.

Soluble MHC I and soluble MIC molecules: potential therapeutic targets for cancer

It has become clear that soluble MHC I (sMHC I) and soluble MIC (sMIC), which are highly elevated in sera of cancer patients, can be viewed to be tolerogenic, and that metalloproteinases are involved in their generation process. In this review, an overview is provided of the recent progress made in the sMHC I and sMIC fields, with emphasis on their structure, formation, and function, and the key-questions that still await answers are addressed. Understanding better their formation mechanism, it will become more feasible to modulate the immune responses in cancer patients by targeting molecules involved in their generation process.

Unexpected suppression of anti-Fya and prevention of hemolytic disease of the fetus and newborn after administration of Rh immune globulin

BACKGROUND

Rh immune globulin (RhIG) has been used successfully for many years for the antenatal suppression of anti-D in D- mothers carrying D+ babies to prevent hemolytic disease of the fetus and newborn. Although the mechanism of RhIG-induced immunosuppression remains unknown, a recent report (TRANSFUSION 2006;46:1316-22) has shown that women receiving RhIG produce elevated levels of transforming growth factor (TGF)β-1, a powerful immunosuppressant cytokine. It was suggested that induction of TGFβ-1 and immunosuppression may be independent of cognate antigen recognition by RhIG. Herein, we present a description of a mother and baby that supports this hypothesis.

STUDY DESIGN AND METHODS

Red blood cells and serum were analyzed using saline-tube indirect antiglobulin test methods. RhIG (RhoGAM) was administered after each amniocentesis performed at 28, 31, and 36 weeks' gestation.

RESULTS

A group A, D-(cde), K+, Fy(a-b+), MNs, Jk(a+b+) mother with no detectable anti-D had an anti-Fy(a) titer of 4096 before RhIG but only 256 after RhIG. Mother gave birth to a group O, D-(cde), Fy(a+b+) healthy baby boy having a weak-positive direct antiglobulin test with anti-Fy(a) eluted from his cells and the titer in the cord serum was 4.

CONCLUSION

This case demonstrates the potential immunosuppressive properties of RhIG for down regulation of a possible clinically significant alloantibody, not anti-D, where no D+ antigen is in the circulation of the mother. The case illustrates the potential utility for using RhIG to modulate antibody levels in situations other than for classical suppression of anti-D production. Although the mechanism in this case is unknown, TGFβ-1-mediated or antibody-mediated immunosuppression to soluble nonparticulate antigens are possible mechanisms.