scholarly journals Plasmodium vivax gametocytes in the bone marrow of an acute malaria patient and changes in the erythroid miRNA profile

2017 ◽  
Vol 11 (4) ◽  
pp. e0005365 ◽  
Author(s):  
Barbara Baro ◽  
Katrien Deroost ◽  
Tainá Raiol ◽  
Marcelo Brito ◽  
Anne C. G. Almeida ◽  
...  
Author(s):  
Marcelo A M Brito ◽  
Bàrbara Baro ◽  
Tainá C Raiol ◽  
Alberto Ayllon-Hermida ◽  
Izabella P Safe ◽  
...  

Abstract Background The presence of Plasmodium vivax malaria parasites in the human bone marrow (BM) is still controversial. However, recent data from a clinical case and experimental infections in splenectomized nonhuman primates unequivocally demonstrated the presence of parasites in this tissue. Methods In the current study, we analyzed BM aspirates of 7 patients during the acute attack and 42 days after drug treatment. RNA extracted from CD71+ cell suspensions was used for sequencing and transcriptomic analysis. Results We demonstrated the presence of parasites in all patients during acute infections. To provide further insights, we purified CD71+ BM cells and demonstrated dyserythropoiesis and inefficient erythropoiesis in all patients. In addition, RNA sequencing from 3 patients showed that genes related to erythroid maturation were down-regulated during acute infections, whereas immune response genes were up-regulated. Conclusions This study thus shows that during P. vivax infections, parasites are always present in the BM and that such infections induced dyserythropoiesis and ineffective erythropoiesis. Moreover, infections induce transcriptional changes associated with such altered erythropoietic response, thus highlighting the importance of this hidden niche during natural infections.


Author(s):  
Nupur Rastogi ◽  
Neha Rehman

Background: Bone marrow aspiration done in cases of repeated fever, fever of unknown origin, pancytopenia to detect Malaria parasite in bone marrow.  The study was undertaken to evaluate the role of bone marrow aspiration in establishing the etiology of Plasmodium vivax in cases of pancytopenia or thrombocytopenia in recurrent fever or fever of unknown origin.Methods: Patients of different age groups presenting with recurrent fever or fever of unknown origin with pancytopenia or thrombocytopenia from Jan 2015 to Oct 2017. Out of the 108 bone marrow aspirations abiding the above criteria 47 showed presence of Plasmodium vivax trophozoites in bone marrow.Results: The age of patients varied from 8 months to 65 years. 47 cases showed presence of Plasmodium vivax trophozoites, mainly with hyperplastic marrow showing normoblastic and megaloblastic hyperplasia, presence of hemophagocytosis in 6 cases and also 2 cases showing increase in plasma cells.Conclusions: Bone marrow aspiration studies are of vital importance in diagnosing malarial infection in endemic areas as being one of the cause of pancytopenia or thrombocytopenia.


Parasitology ◽  
2018 ◽  
Vol 145 (13) ◽  
pp. 1765-1771 ◽  
Author(s):  
Miles B. Markus

AbstractA curious aspect of the evolution of the hypnozoite theory of malarial relapse is its transmogrification from theory into ‘fact’, this being of historical, linguistic, scientific and sociological interest. As far as it goes, the hypnozoite explanation for relapse is almost certainly correct. I contend, however, that many of the genotypically homologous, non-reinfection, relapse-likePlasmodium vivaxrecurrences that researchers ascribe to hypnozoite activation are probably hypnozoite-independent. Indeed, some malariologists are starting to recognize that homologousP. vivaxrecurrences have most likely been overattributed to activation of hypnozoites. Hitherto identified, non-hypnozoite, possible plasmodial sources of recurrence that must be considered, besides circulating erythrocytic stages, include parasites in splenic dendritic cells, other cells in the spleen (in addition to infected erythrocytes there), bone marrow (importantly) and the skin. I argue that we need to take into account the possibility of a dual or multiple extra-vascular origin ofP. vivaxnon-reinfection recurrences, not arbitrarily discount it. The existence of aP. vivaxreservoir(s) is a topical subject and one of practical importance for malaria eradication. Pertinent drug-associated matters are also discussed, as is the dormancy-related significance of clues provided by blood-stage-induced malarial infection.


Blood ◽  
2015 ◽  
Vol 125 (8) ◽  
pp. 1203-1205 ◽  
Author(s):  
Alfredo Mayor ◽  
Pietro Alano
Keyword(s):  

2018 ◽  
Author(s):  
Célia Dechavanne ◽  
Sebastien Dechavanne ◽  
Sylvain Metral ◽  
Brooke Roeper ◽  
Sushma Krishnan ◽  
...  

AbstractThe gene encoding the Duffy blood group protein (Fy, CD234; additional designations Duffy Antigen Receptor of Chemokines [DARC] and Atypical Chemokine Receptor 1 [ACKR1]) is characterized by a SNP in a GATA-1 transcription factor binding site associated with the erythrocyte silent (ES) phenotype.FYEShomozygous people are viewed to be highly resistant to blood stage infection withPlasmodium vivax. Increasingly, however, studies are reportingP. vivaxinfections in Fy-negative individuals across malarious African countries whereFYESapproaches genetic fixation. This suggests thatP. vivaxhas evolved a Fy-independent RBC invasion pathway, or that the GATA-1 SNP does not abolish Fy expression. Here, we tested the second hypothesis through binding studies to erythroid lineage cells using recombinantP. vivaxDuffy binding protein, the parasite’s invasion ligand and Fy6-specific antibodies. We first observed variable Fy expression on circulating RBCs, irrespective ofFYgenotype;FYESRBCs were periodically Fy-positive. Furthermore, during thein vitroerythroid differentiation of CD34+ cells and onex vivobone marrow samples, we observed Fy expression on erythroid precursor cells fromFYESpeople. Finally, the Fy6-specific nanobody, CA111 was used to capture Fy from the surface ofFYESRBCs. Our findings reveal that the GATA-1 SNP does not fully abolish Fy expression and provide insight on potential susceptibility of Fy-negative people to vivax malaria.SignificanceDuffy blood group negativity results from a single nucleotide polymorphism (SNP) in the gene promoter, and reaches genetic fixation in many African ethnicities. Because the Duffy protein (Fy) is an important contact point duringPlasmodium vivaxhuman red blood cell invasion, Fy-negativity is considered to confer resistance toP. vivaxmalaria. With recent studies in African countries reportingP. vivaxinfection in Fy-negative people, we studied Fy expression across erythroid development. Here we report that theFYpromoter SNP does not abolish Fy protein expression in erythroid progenitors developing in the bone marrow. These results further emphasizes the importance of reticulocytes as targets forP. vivaxblood stage infection and propose a mechanism forP. vivaxinfections in Fy-negative people.


Acta Medica ◽  
2019 ◽  
Vol 50 (2) ◽  
pp. 16-24
Author(s):  
Beren Karaosmanoglu ◽  
Ekim Zihni Taskiran ◽  
Dilara Dalkiran

Mesenchymal Stem Cells (MSCs) are one of the most important elements of bone marrow microenvironment, which has a role in stromal support and stem cell differentiation. Exosomes are small vesicles that responsible from various cellular roles such as cell-cell communication and cell signaling, which may affect nearby and distant cells/tissues. MSCs have therapeutic importance because of their multipotency and immune modulation potentials also with their exosomes. Erythropoietin (Epo), produced by liver hepatocytes, is responsible for erythroid differentiation (erythropoiesis) in bone marrow. In addition, Epo treatment of several cell types including MSCs, showed therapeutic effects in various diseases. Objective:The aim of this study is to examine the effect of erythropoietin on bone marrow MSCs transcriptome and exosome derived miRNA profile. Materials and Methods:Effect of 3 different doses of Epo (1 IU/ml, 10 IU/ml and 100 IU/ml) for 48 hours on MSCs transcriptome profile was analyzed. The results illustrated that 10 IU/ml Epo treatment has the most effective concentration in terms of gene expression profile. Therefore, small RNA libraries targeting miRNA was analyzed with 10 IU/ml Epo treated versus non treated groups with next generation sequencing. Results:We found that Epo treatment slightly changed global gene expression profile. On the other hand, it was observed that Epo treated MSCs have different exosomal miRNA profile. Conclusion:Differentially expressed exosomal miRNAs may have therapeutic effects in different conditions. It will be important to perform further studies with in vitro models, mimicking different physiological conditions and diseases for MSCs and exosome biology.


2017 ◽  
Vol 55 ◽  
pp. S117-S118
Author(s):  
K. Ohyashiki ◽  
Y. Saito ◽  
S. Imanishi ◽  
T. Umezu ◽  
S. Yoshizawa ◽  
...  

1998 ◽  
Vol 21 (3) ◽  
pp. 313-314 ◽  
Author(s):  
J O’Donnell ◽  
JM Goldman ◽  
K Wagner ◽  
G Ehinger ◽  
N Martin ◽  
...  

1989 ◽  
Vol 63 (9) ◽  
pp. 1043-1046 ◽  
Author(s):  
Hiroshi YAMAKAWA ◽  
Masaya KIYOTAKI ◽  
Yutaka HATTORI ◽  
Mitsuo OBANA ◽  
Yasuo MATSUOKA ◽  
...  

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