HPA antibodies in Algerian multitransfused patients: Prevalence and involvement in platelet refractoriness

Investigation of the correlation between platelet antibodies and peripheral blood cytopenia in patients with hepatocellular carcinoma

The primary triggers that stimulate the body to generate platelet antibodies via immune mechanisms encompass events such as pregnancy, transplantation, and blood transfusion. Interestingly, our findings revealed that a subset of male patients with hepatocellular carcinoma (HCC), despite having no history of transplantation or blood transfusion, has shown positive results in platelet antibody screenings. This hints at the possibility that certain factors, potentially related to the tumor itself or its treatment, may affect antibody production. To delve the causes we initiated this study. We employed a case-control study approach to analyze potential influential factors leading to the positive results via univariate and multivariate regression analysis. We utilized Kendall's tau-b correlation to examine the relationship between the strength of platelet antibodies and peripheral blood cytopenia. Antitumor medication emerged as an independent risk factor for positive results in HCC patients, and the strength of platelet antibodies positively correlated with the severity of anemia and thrombocytopenia. Without history of blood transfusion, transplantation, pregnancy, those HCC patients underwent recent tumor medication therapy are experiencing peripheral erythrocytopenia or thrombocytopenia, for them platelet antibody screenings holds potential clinical value for prevention and treatment of complications like drug-immune-related anemia and/or bleeding.

Red blood cell alloimmunization in Iran: A Comprehensive review of the literature

BACKGROUND:

Alloimmunization is an immune response against foreign antigens which introduced into the body through transfusion, pregnancy, or transplantation. This phenomenon is a big challenge in patients, which require regular transfusions. In the current study, we tried to have a comprehensive review on the status of alloimmunization in Iran. For this purpose, we searched for papers investigating alloimmunization in transfusion-dependent patients and also in patients with no regular transfusions who are candidate for surgery or who need blood.

METHODS:

We searched PubMed, Google Scholar, SID, and MAGIRAN databases using the following keywords: “blood transfusion,” “alloimmunization,” “alloantibodies,” “irregular antibodies,” “red cell antibodies,” and “Iran.” No limitation for the date of publication and language of the papers was defined. All the identified records were then screened for the relevance and duplication.

RESULTS:

A total of 22 papers were included in this study. All of the studies were conducted from 1999 to 2016 and providing alloimmunization data from different cities all over of Iran. In general, the results showed that the most prevalent alloantibodies are anti-Kell (anti-K antigen) and anti-Rh system, mainly anti-E, anti-D, anti-C, and anti-c.

CONCLUSION:

Anti-Kell and anti-Rh antibodies are the most prevalent antibodies responsible for alloimmunization in Iranian population.

The clinical characteristics of patients with acute leukemia or stem cell transplantation exhibiting immune based platelet refractoriness

BACKGROUND

To investigate the related factors influencing immune platelet transfusion refractoriness (PTR) in acute leukemia (AL) from induction to consolidation and compare management for immune PTR, so as to improve the Platelet increment in AL.

METHODS

The primary analysis included 890 patients with AL, 225 of whom were the immune PTR (25 %).They are patients in our center from induction to consolidation or transplantation in the past 10 years. Flow cytometry, karyotype characteristics and other basic information were compared between the immune PTR vs control (no-PTR) groups. We analyzed the treatment outcomes of immune PTR including matched platelets, intravenous immunoglobulin (IVIG), increasing apheresis platelet does.

RESULTS

Immune PTR is more likely to occur in patients with poor prognosis in acute lymphoblastic leukemia (ALL) (P = 0.01).There is a relation between NPM1 mutation and occurrence of immune PTR (P = 0.029).The incidence of PTR at 35-59Y was higher than that at <35Y(OR = 0.68, 95 % CI = 0.48-0.96) and ≥60Y(OR = 0.49,95 % CI = 0.28-0.83), and the difference was statistically significant(P = 0.03, P = 0.01).The Platelet increment with 1 unit (u) was 47.12 %, 2 u increased to 71.14 %, and the matched 2 u (75.11 %) had the best effect. IVIG improved the Platelet increment, but there was no difference between 0.4 g/kg IVIG and 1 g/kg IVIG. Immune PTR is more likely to occur in the ages of 35-60 years.

CONCLUSION

There are specific AL patient characteristics which predispose to the phenomenon of immune based PTR. Meanwhile, increasing the IVIG dose could not improve Platelet increment obviously.

REFRACTORINESS TO DONOR PLATELETS TRANSFUSION IN PATIENTS WITH APLASTIC ANEMIA AND HEMOBLASTOSIS

Refractoriness to transfusions of platelet concentrates (PC) adversely affects the conduct of complex therapy in hematological patients. Individual selection of platelets is recommended for such patients. In cases of high degree of alloimmunization with the formation of polyspecific antibodies, when individual selection is difficult, procedures plasmapheresis (PPs) is included in the treatment program.

Aims: to evaluate the effectiveness of PC transfusions by individual selection in patients refractory to transfusions and the use of PPs as a second line therapy in combination with individual platelet selection.

Materials and methods: from September 2015 to December 2017, 91 patients with refractory to PC transfusions from 1263 patients who received PC transfusion were observed in the center’s clinics. The median age was 43 (18–71) years. M/F – 38/53. Patients: 20 – aplastic anemia (AA), 17 – myelodysplastic syndrome (MDS), 45 – acute myeloid leukemia (AML), 9 – acute lymphoblastic leukemia (ALL). All patients underwent PC transfusion by individual selection (HLA/HPA) Immucor’s Capture-P solid phase technology. In 28 (30 %) of 91 patients, due to the inability to select, there was a need for PP as a second line therapy. Patients: AA – 4 (20 %); MDS – 8 (47 %); AML – 12 (26 %); ALL– 4 (44 %). The median age was 48 (23–71) years. M/F – 8/20. From 2 to 15 procedures were performed (on average – 6) for each patient. All patients received PC transfusions by individual selection by cross-matching immediately after the PP procedure. The efficacy of PC transfusions was assessed by Absolute Platelet Increment (API) and Corrected Count Increment (CCI), relief of hemorrhagic syndrome.

Results: in 26 of 28 refractory to PC transfusions patients, in the absence of compatible donor platelets, carrying out PPs in combination with subsequent individual platelet selection promoted relief of hemorrhagic syndrome, increase in API from 3.3 × 109/L at 29.5 × 109/L and CCI from 1.3 to 10.7. Against the background of PPs, combined with individual selection, the degree of alloimmunization (the percentage of incompatible pairs) decreased on average: AA (n = 4) – from 91.7 to 50.2 %; MDS (n = 8) – from 89.6 to 31.6 %; AML (n = 12) – 86.0 to 40.5 % and ALL (n = 4) – from 91.7 to 37.7 %. In 2 patients with a high degree of alloimmunization and after carrying out PPs, it was not possible to select compatible platelets, PC transfusions were ineffective (API = 5 × 109/L, CCI = 1), and hemorrhagic syndrome was not completely managed, but its severity was reduced.

Conclusions. With the development of refractoriness to PC transfusions and the ineffectiveness of individual platelet selection, PPs should be used as the second line of therapy, which, combined with individual selection, increases the likelihood of compatible donor-recipient pairs and increases the clinical efficacy of PC transfusions. When PPs is ineffective in combination with individual selection, it is necessary to exclude the syndrome of increased consumption and other mechanisms of refractoriness.

Blood and Blood Components: From Similarities to Differences

Blood transfusion is made possible because, in most countries and organizations, altruistic individuals voluntarily, anonymously, and generously donate (without compensation) either whole blood or separated components that are then processed and distributed by professionals, prior to being allocated to recipients in need. Being part of modern medicine, blood transfusion uses so-called standard blood components when relative to cellular fractions and fresh plasma. However, as will be discussed in this paper, strictly speaking, such so-called labile blood components are not completely standard. Furthermore, the prevalent system based on voluntary, non-remunerated blood donation is not yet universal and, despite claims by the World Health Organization that 100% of blood collection will be derived from altruistic donations by 2020 (postponed to 2025), many obstacles may hinder this ambition, especially when relative to the collection of the enormous amount of plasma destined for fractionation into plasma derivative or drugs. Finally, country organizations also vary due to the economy, sociology, politics, and epidemiology. This paper then, discusses the particulars (of which ethical considerations) of blood transfusion diversity and the consequences for donors, patients, and society.

[Study on the expression of T, B lymphocyte antigen and platelet antibodies in patients with platelet transfusion refractoriness]

OBJECTIVE

To explore whether T lymphocytes subgroup, B lymphocytes, platelet antigen CD41a, CD61 or platelet antibodies are involved in the platelet transfusion refractoriness.

METHODS

Forty-seven patients diagnosed as platelet transfusion refractoriness and 32 patients that achieved effective platelet therapy were ennolled in this study. Flow cytometry was performed to detect the proportion of cytotoxic T cell (CD3(+)CD4(-)CD8(+)), helper T cell (CD3(+)CD4(+)CD8(-)) and B lymphocytes (CD19 (+) ), and the expression of platelet glycoproteins, including CD41a and CD61, while platelet antibodies were also measured by solid-phase agglutination.

RESULTS

The significant lower level of helper T cell (36.60% vs 48.53%), higher level of cytotoxic T cell (53.26% vs 44.02%) and lower cytotoxic/helper T cell ratio (0.85 vs 1.31) were observed in platelet refractoriness group when compared with effective platelet therapy group (P<0.05). However, the significant difference was not observed in B lymphocytes between the two group (3.02% vs 2.85%, P>0.05). Platelet glycoproteins CD41a and CD61 and antibodies were both expressed at high levels in platelet refractoriness group (88.10% vs 51.69%, 88.36% vs 51.83%, 85.37% vs 14.82%, respectively, P<0.05).

CONCLUSIONS

Activation of cytotoxic T cells, suppression of helper T cells, higher expression level of platelet glycoproteins CD41a and CD61 as well as the development of anti-platelet antibodies are involved in the immunologic mechanism of platelet refractoriness.