[Age does not affect the outcome of allogeneic hematopoietic precursor transplantation for acute myeloid leukemia]

BACKGROUND

In our country, transplantation centers differ in the age limit for allogeneic hematopoietic transplantation (ALOHT). In our program, transplants with age- adjusted conditioning are performed in patients until 70 years old. Currently more than 60% of ALOHT reported to the Center for International Bone Marrow Transplantation Research (CIBMTR) are performed in patients older than 40 years.

AIM

To report our experience with ALOHT in acute myelogenous leukemia (AML), analyzing patient age at transplantation in different periods and transplant results in different age groups.

MATERIAL AND METHODS

A retrospective analysis of the database of adult hematopoietic transplants in AML patients was performed. Demographic data, disease characteristics, transplant data, survival and relapse times, and mortality were collected.

RESULTS

In our program, 1030 transplants were performed in adults and 119 ALOHT were performed in AML patients, between 1990 and 2020. The median age of patients in all periods was 41 years, (range 16-69). The median age was 33 and 45 years, in the periods 1990-2000 and 2000-2020 respectively (p < 0.01). Seventy-eight patients received myeloablative conditioning (median age 44 years) and 41 reduced intensity conditioning (median age 53 years). Five-year overall survival was 44.6% (confidence intervals (CI) 41-48). Non relapse mortality of all periods was 19% (CI 17 - 40%) and relapse rate was 17 % (CI 16-22). No difference in five years overall survival among patients younger than 40, 41 to 50 and over 51 years was observed.

CONCLUSIONS

Overall Survival, non-relapse mortality and relapse rate were similar in younger and older patients in our program and similar to those previously reported in other centers.

Haploidentical transplantation outcomes are comparable with those obtained with identical human leukocyte antigen allogeneic transplantation in Chilean patients with benign and malignant hemopathies

Introduction

Patients with benign or malignant blood disorders, who require allogeneic stem cell transplantation and lack an identical human leukocyte antigen HLA identicalHL sibling donor, could be transplanted with hematopoietic stem cells from unrelated adult or umbilical cord donors. However, in our country, both approaches are costly and time-consuming options.

Methods

Over the last few years, haploidentical modalities have been investigated as an alternative donor source, showing similar results to those obtained with identical HLA donors. We started using T-cell-replete haploidentical with post-transplant cyclophosphamide in 2012 and we presented our experience with patients undergoing haploidentical ransplantation compared to SIB.

Results

Since January 2012 to date, 91 allogeneic transplants have been performed, of which 49 were haploidentical and 42 were HLA identical. The mean age of the patients was 35 years (range: 17–62). The mean CD34/kg × 10⁶ infused per group was 5.93 and 5.89, respectively. Time to granulocyte and platelet engraftment was 11 and 15 days, respectively, for haploidentical, and 12 and 14 days, respectively, for HLA identical (p = 0.10). The 100-day cumulative incidence of global acute GVHD was 34% for haploidentical and 29% for SIHLA identical (p = 0.9). The 2-year overall global graft-versus-host disease was 43% for haploidentical and 41% for HLA identical (p = 0.8). Overall survival, relapse, and transplant and relapse-related mortality were similar between both groups.

Conclusion

Our experience showed that haploidentical has similar outcomes to those obtained with HLA idential and can be performed in our country safely.

Colour Stabilization of Spray-Dried Porcine Red Blood Cells Using Nicotinic Acid and Nicotinamide

The effect of nicotinic acid (NA) and nicotinamide (NAm) on colour parameters (CIE L*, a*, b*) of spray dried red blood cells and colour stability during a 7-weeks storage period at room temperature were investigated. The influence of pH on the colour of powder stabilized with NA or NAm was also determined by using starch gels as a model matrix. The results showed that nicotinic acid at 2% (w/v) considerably prevented colour deterioration of haemoglobin concentrate during spray-drying as well as during the storage period. The powder obtained was clearer, redder and more yellow than the control. A positive effect was also detected with 2.5% (w/v) nicotinamide, but the improvement achieved was never as high as it was when nicotinic acid was used. However, powder containing nicotinamide at 2.5% (w/v) showed higher capacity as a red colourant than nicotinic acid at 2% (w/v) when added to starch gels either at pH 7.5 or 4.5.

Identification of cryptic species of Culicoides (Diptera: Ceratopogonidae) in the subgenus Culicoides and development of species-specific PCR assays based on barcode regions

Culicoides biting midges (Diptera: Ceratopogonidae) are vectors of important diseases affecting wild and domestic animals. During the last decade they have played a major role in the epidemiology of the largest bluetongue epizootic ever recorded in Europe, the disease is transmitted between hosts almost exclusively by bites of Culicoides midges and affects both domestic and wild ruminants however severe disease usually occurs in certain breeds of sheep and some species of deer. An accurate vector identification is of major importance in arthropod borne diseases surveillance, as great differences in vectorial capacity are found even between close species. Unfortunately, specialized taxonomic knowledge of Culicoides identification is rarely available in routine surveillance, mainly based on wing morphology. Recently, some European species of Culicoides belonging to the subgenus Avaritia Fox, 1955 and Culicoides Latreille, 1809 have been described as new bluetongue virus vectors. In the present study, by using a fragment of the barcode region (COI gene) we report the presence of up to 11 species within the subgenus Culicoides in Catalonia (NE Spain), a region recently affected by a bluetongue epizootic. The molecular analysis revealed new non-described cryptic species which were grouped in three complexes of morphologically similar species, two in the Pulicaris complex resembling Culicoides pulicaris, two in the Fagineus complex resembling Culicoides fagineus and three in the Newsteadi complex resembling Culicoides newsteadi. The phylogenetic relationships among them showed that cryptic species detected in both Pulicaris and Fagineus complexes were closely related, whereas those in the Newsteadi complex were more distant. Accurate analysis of all species using morphological and molecular approaches resulted in the detection of diagnostic metric traits for cryptic species and the design of several new species-specific single and multiplex PCR assays to identify unambiguously all the species, most of them still lacking a specific molecular diagnosis.

Widespread Occurrence of Wheat spindle streak mosaic virus in Belgium

In order to assess the occurrence of Wheat spindle streak mosaic virus (WSSMV) in Belgium, a reverse-transcription polymerase chain reaction (RT-PCR) was developed, targeting WSSMV isolates from Canada, France, Germany, Italy, and the United States. The primers also were designed for virus quantification by real-time RT-PCR with SYBR-Green. No cross-reaction with soilborne cereal viruses such as Barley mild mosaic virus, Barley yellow mosaic virus, Soilborne cereal mosaic virus, and Soil-borne wheat mosaic virus was observed. The RT-PCR and real-time quantitative RT-PCR allowed a more sensitive detection of WSSMV than enzymelinked immunosorbent assay. The incidence of WSSMV in Belgium was evaluated using a bioassay with wheat cvs. Cezanne and Savannah and rye cv. Halo, grown in 104 Belgian soils. The presence of WSSMV was detected from plants grown in 32% of the soils. The RT-PCR methods developed here, combined with large sampling, allowed WSSMV to be detected for the first time in Belgium. The real-time quantitative RT-PCR was developed as a tool for evaluating the resistance to WSSMV by quantifying the virus concentration in wheat cultivars.

Changes in the plasma membrane proteins of stallion spermatozoa during maturation in the epididymis

The present paper reports modifications in the electrophoretic and cytochemical characteristics of mature and immature stallion spermatozoa. Some sperm surface glycoproteins (36, 32, 29, 21, 20, 18 kDa) detected in cauda epididymidis spermatozoa, were either absent or present in a very low relative concentration in immature sperm cells. A major 14 kDa protein band, observed in sperm extracts obtained from ductus efferentes, progressively decreased along the epididymal ductus. The nature and distribution of carbohydrate residues on the sperm membrane, during epididymal maturation, was also studied by use of lectin probes. Some protein bands bound concanavalin A while others, as the 36, 32 and 20 kDa proteins, exhibited higher affinity for WGA lectin. The distribution and relative density of mannose-, galactose-, N-acetylglucosamine-, N-acetylgalactosamine-, fucose- and sialic acid-containing macromolecules showed a characteristic pattern depending on the sperm membrane domain and on its origin. Some sperm surface domains displayed affinity for more than one lectin, indicating a diversity in their exposed carbohydrate residues, whereas others bound only one or no lectin. The passage of spermatozoa through the epididymidis was accompanied by changes in the accessibility or abundance of lectin ligands. Some lectins (UEA, WGA, LPA) gave stronger reaction in mature spermatozoa, while others (RCA, WFH, PNA) stained better immature spermatozoa. This remodeling of sperm surface molecules is probably a consequence of interactions between spermatozoa and the epididymal secretions, and may reflect addition or adsorption of new molecules, space configurations changes or biochemical modifications of pre-existing compounds. Our results suggest that the distribution and density of terminal oligosaccharidic residues on the sperm plasma membrane have species-specific characteristics. These post testicular developmental changes may be of significance in the overall understanding of the stallion fertility.