Effect of SARS-CoV-2 and Toxoplasma gondii co-infection on IFN-γ and TNF-α expression and its impact on disease severity

The symptomatology of COVID-19 is dependent on the immune status and the cytokine response of the host. The cytokine level of the host is influenced by the presence of chronic persistent or latent infections with co-pathogens. Parasitic diseases are known to induce host immune-modulation which may impact the response to co-infection. Toxoplasmosis is a widespread protozoal infection that remains quiescent in its latent form to be re-activated during states of immune depression. Clinical data on the relation between toxoplasmosis and COVID-19 cytokine profile and symptomatology are still insufficient. Seventy-nine subjects were included in this study. Patients were diagnosed with COVID-19 by PCR. Serological testing for toxoplasmosis was performed by the detection of anti-Toxoplasma IgG antibodies, in addition to IgG avidity testing. IFN-γ and TNF-α levels were determined by RT-PCR. Among patients diagnosed with COVID-19, 67.1% were seronegative for anti-Toxoplasma IgG, while 32.9% were seropositive. High avidity was found in 10 cases (40% of seropositive cases), 4 of whom required ICU administration, while low avidity was found in 15 cases (60%), 7 of which were administered to the ICU. TNF-α and INF-γ levels were significantly higher in COVID-19 patients than in healthy control subjects. No significant association was found between the seroprevalence of toxoplasmosis and the presence of COVID-19 and its severity. Cytokines were significantly higher in both seropositive and seronegative COVID-19 patients than in their control counterparts. The high prevalence of toxoplasmosis merits further exploration of its relation to COVID-19 by mass studies.

Comparison of T Lymphocyte Subsets and Natural Killer Lymphocytes in Moderate Versus Severe COVID-19 Patients

Severe respiratory involvement that follows a process of immune dysregulation and intense cytokine production remains to be the most dreaded complication of Coronavirus Disease-2019 (COVID-19) infection. The aim of this study was to analyze T lymphocyte subsets and natural killer (NK) lymphocytes in moderate and severe cases of COVID-19 infection and assess their significance in disease severity and prognosis. Twenty moderate cases and 20 severe cases of COVID-19 were studied and compared regarding blood picture, biochemical markers, T lymphocyte population subsets, and NK lymphocytes, which were determined by flow cytometric analysis. On analyzing the flow cytometric data of T lymphocyte cells and their subsets and NK cells in two groups of COVID-19 infection (one group moderate and the other severe cases), some immature NK lymphocyte relative and absolute counts were higher in the severe patients with worse outcome and death, while some mature NK lymphocyte relative and absolute counts were depressed in both groups. Also, interleukin (IL)-6 was significantly higher in severe cases when compared to moderate cases, and there was a positive significant correlation between immature NK lymphocyte relative and absolute counts and IL-6. There was no statistically significant difference between T lymphocyte subsets (T helper and T cytotoxic) with disease severity or outcome. Some immature NK lymphocyte subsets contribute to the widespread inflammatory response that complicates severe cases of COVID-19; therapeutic approaches directed to enhancing NK maturation or drugs that block NK cell inhibitory receptors have a potential role in controlling COVID-19 induced cytokine storm.

Serum Level of High-Mobility Group Box Protein 1 as a Potential Treatment Target in Egyptian Sickle Cell Disease Patients

Background: During tissue injury, high mobility group box 1 (HMGB1) is passively released from necrotic cells and actively secreted by inflammatory cells. Extracellular HMGB1 acts as an amplifier of Toll-Like Receptor (TLR)-dependent inflammation rather than a primary trigger of inflammation. We studied HMGB1 quantitative trait locus reference sequence 2249825 (rs2249825) and its serum level in both sickle cell disease (SCD) patients and healthy subjects to explore its possible role in the pathogenesis of vaso-occlusive crises (VOCs). Methods: HMGB1 rs2249825 was assayed in peripheral blood samples using real-time polymerase chain reaction (RT-PCR). While the serum level was assayed using a two-site enzyme-linked immunosorbent technique (ELISA). Results: Both the SCD patients and the control group had comparable HMGB1 rs2249825 genotype frequencies (P-value >0.05). SCD patients at their steady-state showed statistically significantly higher serum HMGB1 levels than the healthy controls, a median of 0.6 ng/ml with a range of 0.1- 85 ng/ml versus a median of 0.3 ng/ml and a range of 0.1-3 ng/ml (P-value <0.001), respectively. Statistically significant skewed high serum HMGB1 in the VOC samples in contrast to the steady-state samples was observed in the SCD patients with a median of 3.2 ng/ml and a range of 0.3-76.4 ng/ml versus a median of 0.2 ng/ml and a range 0.2-7.4 ng/ml (P-value <0.0001), respectively.     Conclusion: HMGB1 could have a role in the VOC pathogenesis, hence it is suggested as a potential additive therapeutic target in SCD in general and in vaso-occlusions in specific. Keywords: Sickle cell disease, HMGB1, Hemoglobin S

Sarcoidosis beyond pulmonary involvement: A case series of unusual presentations

Unusual presentations of sarcoidosis pose a diagnostic challenge and warrant attention. Hematologic associations: Case 1 (37-years-old male): Pancytopenia: myelofibrosis (leading to sepsis and mortality) following a two-year quiescent course of biopsy-proven-sarcoidosis. Case 2: (38-years-old male): Presentation with thrombocytopenia (5 × 10³/cmm): immune thrombocytopenic purpura (histologically associated with megakaryocytic emperipolesis). Biopsied enlarged lymph nodes demonstrated sarcoidosis. Hematologic sarcoid involvement is usually due to granulomatous bone marrow (3.9%) or splenic infiltration (6–30%); however, the presented manifestations are scarcely reported with a potential significance that is yet to be elucidated. Case 3: Neurologic presentation: 48-years-old female: presentation with bilateral sensorineural hearing loss and facial palsy. Brain magnetic resonance imaging showed leptomeningeal thickening. Biopsied enlarged lymph nodes showed sarcoidosis. Case 4: Neurologic and renal manifestations: 13-years-old male (family history of sarcoidosis): Presenting with acute headache, investigations showed elevated serum creatinine (2.1 mg/dL) and angiotensin converting enzyme, and computed tomography chest and abdominal findings characteristic of sarcoidosis. Associated benign increased intracranial and acute tubulointerstitial nephritis (with eosinophils) were diagnosed upon concordant workup. Of sarcoidosis neurologic affection (5–10%), cranial nerve(s) involvement is among the most common (25–50% of neurosarcoid affection), particularly that of the facial nerve (Case 3). Leptomeningeal enhancement is among the most common neurosarcoid radiologic findings (30–40%). Whereas benign increased intracranial tension (Case 4) is much less reported. Among sarcoidosis renal involvement (35–50%), interstitial nephritis usually presents with granulomatous renal lesions, yet its sole association with sarcoidosis is unusual (Case 4). The portrayed atypical hematologic, neurologic, and renal manifestations further emphasize the masquerading nature of sarcoidosis.

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Although hematologic involvement in sarcoidosis is usually due to granulomatous infiltration of the bone marrow or spleen and/or hypersplenism, associations with hematologic neoplasms or myelodysplastic syndromes have been reported. However, coexisting myelofibrosis (presented in our first patient) is much less reported and raises interest.

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We present a patient with coexistent with ITP (case 2) that was further histologically associated with megakaryocytic emperipolesis. The significance of this association is yet to be elucidated.

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Cranial nerve(s) involvement is among the most widely neurosarcoid manifestations reported which was demonstrated in our third patient. Brain MRI showing evidence of leptomeningeal enhancement which is among the most common radiologic findings of neurosarcoidosis.

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A juvenile-onset patient with a family history of sarcoidosis manifested with benign increased intracranial tension (ICT) and renal affection in the form of tubulointerstitial nephritis. Unlike cranial nerve affection, benign ICT is a rarely reported neurosarcoid manifestation, and renal involvement is usually due to hypercalcemia or granulomatous involvement with or without tubulointerstitial nephritis.

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Although unusual presentations warrant attention as the pose a diagnostic and therapeutic challenge, they should be prudently interpreted.

The Relationship between the Connexin 32 and Connexin 43 Genes and the Pretreatment Stage and Short-term Follow-up of Patients with Acute Myeloid Leukemia

Background

Connexins (Cxs) are gap junction proteins involved in the communication between acute myeloid leukemia (AML) and stromal cells. They consist of intercellular channels termed "connexions", which can cause uncontrolled cell proliferation if dysregulated. This study aimed to evaluate the expression levels of the Cx32 and Cx43 genes and their correlations with other prognostic markers in patients with AML.

Methods

This cross sectional study was performed on peripheral blood samples from 60 newly diagnosed patients with AML and 40 healthy control subjects at Kasr Alainy School of Medicine, Cairo University, from June 2016 to December 2017. The quantitative real-time polymerase chain reaction (qRT-PCR) test was used to examine the relative expression level of Cx43 and Cx32 genes in the patients and the control subjects. The Chi square test or the Fisher exact test was employed to examine the relationship between qualitative variables, while the independent t test or the Mann-Whitney test was employed for quantitative data. All the tests were two-tailed, and a P value of less than 0.05 was considered significant.

Results

Among the patients with AML, 65% had a high Cx32 expression level, whereas 63.3% had a low Cx43 expression level. There was a statistically significant difference in the fold change values of Cx32 and Cx43 expression between the patient group and the control group (P=0.009 vs P=0.013, respectively). There was a remarkable association between both Cxs and CD34 and HLA-DR cells.

Conclusion

Cx expression in samples may add to the diagnostic workup of AML. Although we found a negative correlation between Cx43 expression and the peripheral blood blast percentage, the response after the first induction of chemotherapy showed no significant relationship with Cx43 and Cx32.

Abstract 4123: Investigation of growth factor signaling through macrophage colony stimulating factor (CSF-1) and its receptor (FMS) in the bone marrow stromal microenvironment in acute myeloid leukemia (AML)

Acute myeloid leukemia (AML) is a highly heterogeneous and growth factor-dependent disease of the bone marrow. The bone marrow stromal microenvironment plays a critical role in providing growth and survival signals. hFMS, the human homologue of the Feline (McDonough strain) Sarcoma virus oncogene, also known as macrophage colony stimulating factor 1 receptor (CSF1R, FMS, CD115) is a tyrosine kinase receptor found on mononuclear phagocytes that promotes their growth and differentiation. The human macrophage CSF-1 ligand (MCSF-1, CSF-1) produced by supporting cells in the bone marrow acts on FMS. CSF-1 has a full length secreted isoform v1 and a membrane-bound isoform v3. Upon activation, FMS modulates the activity of important effectors of growth and survival pathways such as the mitogen-activated protein kinase (MAPK)/ERK and phosphoinositol-3 kinase (PI3K)/Akt pathways, respectively. There is a variable association of Fms with the stem cell marker CD34 on AML cells and this suggests different structures within an AML hierarchy. To better understand stromal cell interactions mediated by the CSF-1/FMS axis and examine the high engraftment failures of AML human samples in mice, AML cells were grown on murine stromal cells that were ‘humanized’ through lentiviral-mediated introduction of human CSF-1. The soluble v1 and membrane-bound v3 isoforms of CSF-1 were investigated. We found that stroma-presented CSF-1 effectively supports the growth of leukemic cells in short and long-term growth cultures, with the v3 CSF-1 variant sustaining better growth than v1. Interestingly the FMS-(low)/CD34+ subpopulation displayed significantly better growth on stroma compared to the FMS+ populations. Eventually this subpopulation gave rise to FMS+ cells, suggesting that it may harbor stem or initiating properties. In interrogating molecular signaling events induced by the CSF-1/FMS interaction, we found that the membrane-bound v3 isoform leads to increases in phosphorylation of effectors of the MAPK and PI3k/Akt pathways, namely Akt, p70S6K and 4E-BP1, whereas the v1 variant does not elicit such signals as robustly in leukemic cells grown on stroma. Taken together, this indicates that the manner in which the ligand is presented (soluble vs. membrane-bound) impacts the growth, survival and molecular signaling arising from the leukemic-stromal cell interaction. Future work will involve generation of gene and protein expression profiles of leukemic and stromal cells after grown in co-culture in aims of identifying targets induced by the soluble vs. membrane-bound forms of CSF-1. Particular identification of druggable targets in both leukemic and stromal cell compartments will allow for the design of therapeutic strategies to interfere with leukemic-stromal cell interactions driven by the CSF-1/FMS axis.

Citation Format: Ayesha Rashid, Mohamed Fateen, Aaron Schimmer, Mark Minden. Investigation of growth factor signaling through macrophage colony stimulating factor (CSF-1) and its receptor (FMS) in the bone marrow stromal microenvironment in acute myeloid leukemia (AML). [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4123. doi:10.1158/1538-7445.AM2013-4123

Ancestry and pathology in King Tutankhamun's family

CONTEXT

The New Kingdom in ancient Egypt, comprising the 18th, 19th, and 20th dynasties, spanned the mid-16th to the early 11th centuries bc. The late 18th dynasty, which included the reigns of pharaohs Akhenaten and Tutankhamun, was an extraordinary time. The identification of a number of royal mummies from this era, the exact relationships between some members of the royal family, and possible illnesses and causes of death have been matters of debate.

OBJECTIVES

To introduce a new approach to molecular and medical Egyptology, to determine familial relationships among 11 royal mummies of the New Kingdom, and to search for pathological features attributable to possible murder, consanguinity, inherited disorders, and infectious diseases.

DESIGN

From September 2007 to October 2009, royal mummies underwent detailed anthropological, radiological, and genetic studies as part of the King Tutankhamun Family Project. Mummies distinct from Tutankhamun's immediate lineage served as the genetic and morphological reference. To authenticate DNA results, analytical steps were repeated and independently replicated in a second ancient DNA laboratory staffed by a separate group of personnel. Eleven royal mummies dating from circa 1410-1324 bc and suspected of being kindred of Tutankhamun and 5 royal mummies dating to an earlier period, circa 1550-1479 bc, were examined.

MAIN OUTCOME MEASURES

Microsatellite-based haplotypes in the mummies, generational segregation of alleles within possible pedigree variants, and correlation of identified diseases with individual age, archeological evidence, and the written historical record.

RESULTS

Genetic fingerprinting allowed the construction of a 5-generation pedigree of Tutankhamun's immediate lineage. The KV55 mummy and KV35YL were identified as the parents of Tutankhamun. No signs of gynecomastia and craniosynostoses (eg, Antley-Bixler syndrome) or Marfan syndrome were found, but an accumulation of malformations in Tutankhamun's family was evident. Several pathologies including Köhler disease II were diagnosed in Tutankhamun; none alone would have caused death. Genetic testing for STEVOR, AMA1, or MSP1 genes specific for Plasmodium falciparum revealed indications of malaria tropica in 4 mummies, including Tutankhamun's. These results suggest avascular bone necrosis in conjunction with the malarial infection as the most likely cause of death in Tutankhamun. Walking impairment and malarial disease sustained by Tutankhamun is supported by the discovery of canes and an afterlife pharmacy in his tomb.

CONCLUSION

Using a multidisciplinary scientific approach, we showed the feasibility of gathering data on Pharaonic kinship and diseases and speculated about individual causes of death.