Case report: TP53 c.848G>A germline mutation as a possible screening target at initial diagnosis for acute lymphoblastic leukemia.

BACKGROUD: Li-Fraumeni syndrome is a hereditary tumor syndrome characterized by an elevated risk of malignancy, particularly acute lymphoblastic leukemia (ALL), which can be caused by the heterozygous germline mutation. TP53 gene germline mutation is considered a potential risk factor and crucial prognostic parameter for acute leukemia development and diagnosis, but rarely occurs in adults, and its specific pathogenic significance in acute leukemia is unclear. CASE PRESENTATION: We describes a case of a 45-year-old woman diagnosed with ALL. Whole-exome sequencing approach identified one of the TP53 germline mutations from her bone marrow sample with possible pathogenic significance, c.848G>A (p.Arg283His) heterozygous missense mutation located on exon 8, which was further verified in her hair, oral mucous and nail samples. Family pedigree screening revealed that the same TP53 genetic variant was present in the patient's father and non-donor son, whereas not in the donor. Digital PCR observed that this point mutation frequency dropped post-transplantation but remained low during maintenance therapy when the patient was leukemia-free. CONCLUSION: This suspected Li-Fraumeni syndrome case report with a likely pathogenic heterozygous TP53 variant expands the cancer genetic spectrum. Screening her family members for mutations facilitates identifying the optimal relative donor and avoids unnecessary treatment by monitoring TP53 germline mutations for minimal residual disease following hematopoietic stem cell transplantation. Its potential roles in hematological malignant tumor development and clinical pathogenic implications necessitate further probing.

Case Report: Co-existence of a novel EXOC4-TRHDE gene fusion with PML-RARA in acute promyelocytic leukemia.

Acute promyelocytic leukemia (APL) is a type of myeloid leukemia with a specific chromosomal translocation t(15;17)(q22; q12) forming the PML-RARA fusion gene. However, approximately one third of newly diagnosed patients with APL have additional chromosomal abnormalities. Here, we report a case of APL with co-existence of a novel translocation t(7;12)(q32;q13) involving an out-of-frame fusion between EXOC4 and TRHDE, together with PML-RARA. The patient achieved complete remission after treatment with conventional therapy with all-trans retinoic acid (ATRA) and arsenic trioxide (ATO). Although the causative link between EXOC4-TRHDE and PML-RARA has yet to be established, the patient had a good response to therapy, suggesting that the EXOC4-TRHDE fusion does not affect the efficacy of combined treatment with ATRA and ATO.

Establishing Reference Values for Peripheral Blood Lymphocyte Subsets of Healthy Children in China Using a Single Platform.

Lymphocyte subsets significantly change during childhood; thus, age-matched reference values derived from healthy children are crucial. We established reference values for lymphocyte subsets, including T cells (CD3+), CD4 T cells (CD3 + CD4+), CD8 T cells (CD3 + CD8+), double negative T (DNT) cells (CD3 + CD4-CD8-), B cells (CD3-CD19+), NK cells (CD3-CD56+), and NKT-like cells (CD3 + CD56+) in the peripheral blood of 813 healthy children. We used the method of the international standard document (Clinical Laboratory Standard Institute C28-A3) to establish reference intervals with a single platform. First, we used the Skewness and Kurtosis test to analyze the normality of the data. The nonnormally distributed data was transformed into approximately normal distribution by the Box-Cox transformation. Second, we used the Tukey's method to eliminate outliers. Further, all the subjects were grouped into subgroups according to sex (male and female) and age (0-1 month, 2-12 months, 1-3 years, 4-6 years, and 7-18 years). We used the standard normal deviation test (Z-test) to evaluate whether age and sex were possible grouping factors. The analyses indicated age to be an important factor associated with changes in lymphocyte subsets. The absolute number of lymphocyte subsets and total number of lymphocytes, T cells, CD4 T cells, CD8 T cells, and B cells gradually increase from birth to 12 months and then gradually decrease with age. Furthermore, CD4 T cells and the ratio of CD4+/CD8+ gradually decrease with age. In contrast, CD8 T and DNT cells gradually increase with age. The percentage and number of NK and NKT-like cells gradually increase with age and remain stable between 1 and 18 years of age. In conclusion, the age-related reference intervals established in healthy children in this study can aid in monitoring and assessing the changes in immune levels in diseased conditions.

Reference ranges of T lymphocyte subsets by single-platform among healthy population in southwest China.

BACKGROUND: Appropriate reference ranges of T lymphocyte subsets are essential for immune status evaluation of patients with immunological diseases. We aim to establish the age- and sex-related reference intervals of T lymphocyte subsets by single-platform for the southwest China population using the indirect method with the data resulting from 53,822 cases of periodic health examination individuals in the Laboratory Information System (LIS) of West China Hospital from 2018 to 2020. METHODS: We used the Box-Cox conversion combined with the Tukey method to normalize the data and eliminate the outliers, and the nonparametric method to estimate the 95% distribution reference intervals. RESULTS: We initially established the reference ranges of T lymphocyte subsets by single-platform among healthy population in southwest China by indirect method (See text for details). Using the standard normal deviate test (z-test) suggested by Harris and Boyd according to CLSI EP28-A3C, which is more scientific, we found the reference ranges of T lymphocyte subsets should be differentiated by ages and genders since the reference ranges of T lymphocyte subsets by single-platform in different ages and genders are significantly different. CONCLUSIONS: We further demonstrated the absolute count of CD3 + T cell, CD3 + CD4 + T cell, CD3 + CD8 + T cell decreased with aging, which is more marked in men and CD3 + CD8 + T cell count, and the obtained reference intervals were superior to the reference intervals derived from the reagent specification currently in use.

Dynamic monitoring of immune function indexes in COVID-19 patients.

We conducted a retrospective analysis of the clinical characteristics and dynamic variations of immune indexes in nine COVID-19 patients in Zigong, China. We used flow cytometry and enzyme-linked immunosorbent assays to measure the absolute levels of CD4 and CD8 lymphocytes and SARS-CoV-2 antibodies, respectively. We found that CRP, LDH, HBDH, CD4/CD8 and IgE levels were increased in 6/9 patients, while PA and the absolute numbers of CD4 and CD8 lymphocytes decreased in 7/9 patients. From disease onset through 63 days of follow-up, SARS-CoV-2 IgG levels were consistently higher than those of SARS-CoV-2 IgM, reaching peaks on days 28 and 13, respectively. IgM levels decreased to normal 35 days after disease onset, while IgG levels remained elevated through day 63. IgE levels varied similarly to SARS-CoV-2 IgM. Our results suggest that SARS-CoV-2 may elicit allergic immune responses in patients and that the levels of CRP, PA, LDH, and HBDH, as well as the absolute numbers of CD4 and CD8 lymphocytes could be used as early diagnostic markers of SARS-CoV-2 infection. Lastly, the dynamic variation of SARS-CoV-2 antibodies could guide the timing of blood collection for plasma exchange.

[Introplasmic IFN-γ level in circulating T cells detected by flow cytomertry and its relation with treatment efficiency in the patients with aplastic anemia].

This study was aimed to investigate the effects of the introplasmic interferon-γ level in circulating T cell of patients with aplastic anemia (AA) and its clinical significance. The interferon-γ level before and after immuno-suppressive therapy was monitored by flow cytometry. The results indicated that the higher interferon-γ level was detected in 28 out of 50 AA patients, detected rate was 56%. The effective rate of immunosuppressive therapy for AA patients with higher interferon-γ level was up to 85.7% (24/28). The decrease of interferon-γ level in these patients positively correlated with hemogram recovery to normal level and obviously earlier than hematologic remission. It is concluded that the immunosuppressive therapy shows better efficacy for AA patients with high interferon-γ level, moreover the change of interferon-γ level is earlier than hematologic change, that is important for predicting the therapeutic efficacy and relapse of disease.