OBJECTIVE: To explore the clinical application value of serum light chain (sLC) in the diagnosis and therapeutic efficacy evaluation for multiple myeloma. METHODS: 46 patients with newly diagnosed multiple myeloma were selected as MM group and 50 healthy persons as control group. Rate scattering immunoturbidimetry was used to detect serum light chain and immunoglobulin (Ig) in two groups, serum protein electrophoresis was used to detect M protein by agarose gel. Then, the sensitivity and specificity of the two methods in MM diagnosis were analyzed and compared, and the significance of sLC detection in MM diagnosis were discussed. In addition, 15 MM patients after received conventional therapy were tracked, sLC levels in five different therapentic times were recorded, and the effect of sLC in efficacy evaluation of MM was analyzed. RESULTS: There were 11 cases of IgA type, 15 cases of IgG type, 8 cases of light chain κ type, 8 cases of light chain λ type, 2 cases of IgD type, and 2 cases of non-secretion type. The sLC-κ, sLC-λ and their ratio (including light chain type and double clone type), IgA and IgG (except IgD type), as well as albumin, beta-globulin and gamma-globulin levels showed statistically significant differences (P＜0.05) compared with the control group. The sensitivity of serum protein electrophoresis, Ig quantification, sLC and its ratio in the diagnosis of multiple myeloma were 57%, 76% and 65%, and their specificity were 83%, 61% and 90%, respectively. After the second or third chemotherapy, the sLC-κ/λ ratio gradually approached the normal range as the disease reliefes, and the sLC-κ/λ ratio continued to be on or off the line at outliers or further away from the reference value as the disease progresses in MM patients with κ type or λ type. CONCLUSION sLC detection shows positive significance in early diagnosis of multiple myeloma, SLC monitoring can be used for the efficacy evaluation for treatment of MM patients.
Humans ; Immunoglobulin kappa-Chains ; Immunoglobulin lambda-Chains ; Multiple Myeloma ; diagnosis

OBJECTIVE: To investigate the comparability of the Freelite, Binding Site, Beckman and N Latex FLC, Siemens in the detection of serum free light chain (sFLC) . METHODS: Fifty newly diagnosed multiple myeloma (MM) patients in Tianjin Institute of Blood Research from November 2019 to February 2020 were enrolled. The two systems (Freelite, Binding Site, Beckman and N Latex FLC, Siemens) were used to detect the sFLC of the samples. Outlier detection was performed by ESD method, methodological comparison and deviation assessment were performed by Passing-Bablok regression and Bland-Altman regression. RESULTS: Both the systems could quantitatively analyze free kappa light chain serum samples and free lambda light chain samples. Freelite, Binding Site, Beckman and N Latex FLC, Siemens free light chain test showed FLC-κ：36.5 (6.5, 194), 40.5 (6.94, 288), FLC-λ: 30.1 (4.3, 170.5), 35.1 (2.28, 526), rFLC (FLC-κ/ FLC-λ) : 0.82 (0.05, 43.25), 1.03 (0.03, 32.04), dFLC (｜FLC-κ- FLC-λ｜) : -5.8 (-161.97, 183.7), 1.1 (-505.1, 279.01), which existed no outliers. There were systematic differences, and the deviation level was not within the clinically acceptable range. CONCLUSION Both the systems can meet the needs of clinical diagnosis and treatment, but there is a significant deviation between the two systems, the results are not comparable, and should be analyzed separately. In particular, the same system should be selected for monitoring the prognosis of MM.
Humans ; Immunoglobulin Light Chains ; Immunoglobulin kappa-Chains ; Immunoglobulin lambda-Chains ; Latex ; Multiple Myeloma/diagnosis*

OBJECTIVE: To analyze the clinical significance of serum free light chain (sFLC) and sFLC-κ/λ ratio in patients with newly diagnosed multiple myeloma (MM), so as to provide the theoretical basis for the diagnosis, treatment and prognosis of MM patients. METHODS: A total of 43 patients newly diagnosed as MM in our hospital and 40 cases of other diseases that could cause sFLC increase were selcted. The clinical features of newly diagnosed MM patients were analyzed. On the basis of the type of sFLC, MM patients were divided into sFLC-κ and sFLC-λ group. The correlation of sFLC with clinical index in two groups was analyzed. The difference of sFLC-κ/λ ratio between MM and non-MM patients was analyzed. According to whether the involved/uninvolved sFLC ratio was greater than 100, the MM patients were divided into the low ratio and the high ratio group. The clinical index of these 2 groups were analyzed. RESULTS: Among MM patients, IgG type was the most. In sFLC-κ and -λ groups, the hemoglobin level negatively correlated with sFLC (r=-0.307, r=-0.494, P＜0.05), and the serum β2 microglobulin level positively correlated with sFLC (r=0.453, r=0.689, P＜0.05), and myeloma cells ratio also positively correlated with sFLC (r=0.307, r=0.309, P＜0.05). The concentration of albumin, lactate dehydrogenase and serum calcium did not correlate with sFLC (P＞0.05). The serum creatinine level also did not correlate with sFLC in the sFLC-κ group (P＞0.05), but in the sFLC-λ group they were obviously positive (r=0.697, P＜0.01). The ratio of sFLC-κ/λ ＜0.26 or ＞1.65 in MM patients was higher than that of non-MM patients, and the ratio of involved/uninvolved sFLC≥100 in MM patients was also higher than that of non-MM patients with statistically significant differences (P＜0.01). The levels of serum albumin, creatinine and β2 microglobulin, as well as myeloma cell ratio and ISS international staging of the patients between 2 groups were significantly different (P＜0.05), while the differences in sex, age and levels of hemoglobin, lactate dehydrogenase and blood calcium were not significant between the 2 groups (P＞0.05). CONCLUSION The light chain type λ in MM patients correlates with renal damage. The abnormalities of sFLC-κ/λ ratio occur mostly in MM patients. The MM patients with involved/uninvolosed sFLC ratio ≥100 show the severe symptoms and poor prognosis.
Humans ; Immunoglobulin Light Chains ; Immunoglobulin kappa-Chains ; Immunoglobulin lambda-Chains ; L-Lactate Dehydrogenase ; Multiple Myeloma ; Prognosis

OBJECTIVETo investigate the clinical significance of serum free light chain (sFLC) detection in light chain multiple myeloma (LCMM).

METHODSA total of 37 newly diagnosed LCMM patients were enrolled in this study, including 17 patients with k light chain type and 20 patients with λ light chain type, the sFLC and 24 hours urine light chain (ULC) were measured before and after chemotherapy. The correlation of sFLC level with ULC and renal impairment was analyzed.

RESULTSAll the patients displayed an abnormally increased level of sFLC at diagnosis wtih median value of 105.44 mg/L and 146.39 mg/L for k and λ light chain types, respectively. The sFLC did not correlate with ULC before and after chemotherapy. Among the 12 patients with very good partial remission and normal ULC level, the sFLC still was abnormally increased in 8 patients. Renal impairment was associated with the urine λ-type light chain, and the area under the ROC curve of urine λ light chain at diagnosis is 0.792 (P = 0.031).

CONCLUSIONAll patients with LCMM show an abnormally increased level of sFLC at diagnosis. sFLC can be used to monitor the response to chemotherapy because it is more sensitive for analysis of therapeutic effect than urine λ light chain.

Humans ; Immunoglobulin Light Chains ; blood ; Immunoglobulin kappa-Chains ; blood ; Immunoglobulin lambda-Chains ; blood ; Multiple Myeloma ; blood ; drug therapy ; Renal Insufficiency

Primary cutaneous plasmacytoma is a rare type of cutaneous B-cell lymphoma that arises primarily in the skin, and this is derived from clonally expanded plasma cells with various degrees of maturation and atypia. A 72-year-old man had an asymptomatic, solitary reddish to violaceous nodule on the back for about 4 months. The histologic finding of the skin biopsy specimen demonstrated an infiltration of variably matured plasma cells in the dermis, and these cells showed a monotypic expression of immunoglobulin kappa chains on immunohistochemical staining. Staging investigations excluded any extracutaneous manifestations of the disease. Only a few cases of primary cutaneous plasmacytoma have been published in the Korean dermatologic literature. Herein, we report on an interesting case of primary cutaneous plasmacytoma with monoclonality of kappa chains.
Aged ; Biopsy ; Dermis ; Humans ; Immunoglobulin kappa-Chains ; Lymphoma, B-Cell ; Plasma Cells ; Plasmacytoma ; Skin

OBJECTIVE: To gain insights into structural characteristics of immunoglobulin kappa chain repertoire expressed in the inflammed synovium of rheumatoid arthritis (RA), we analyzed V kappa transcirpts expressed in the synovium of a patient with longstanding RA and compared to those expressed in the PBLs of RA and normal controls. METHODS: RT-PCR was done to amplify kappa chain transcripts from RA synovial lymphocytes and the cDNA sequences were compared to those from PBL of RA patient or normal control. RESULTS: Kappa chain repertoire from RA patient's synovial lymphocytes or PBL revealed increased somatic mutation and unusually long complementarity determining region (CDR) 3 compared to normal control. CONCLUSIONS: These changes in kappa chain repertoire in RA patient are suggesting that the antibody repertoire expressed in the synovium or PBL is unique and may be related with systemic dysregulation of B cell development
Arthritis, Rheumatoid ; Autoimmune Diseases* ; Complementarity Determining Regions ; DNA, Complementary ; Genes, Immunoglobulin* ; Humans ; Immunoglobulin kappa-Chains ; Immunoglobulins* ; Lymphocytes ; Synovial Membrane*

A 70-yr-old woman was hospitalized with a history of dry cough. Bronchial endoscopy and transbronchial lung biopsy were performed. However, the findings of histopathology and immunohistochemistry were not sufficient to decide whether the lesion was benign or malignant, because of the presence of crush artifacts in the biopsy specimens. We performed B-cell clonality studies using BIOMED-2 multiplex PCR (InVivoScribe Technologies, USA) to detect clonal rearrangements in the immunoglobulin gene. The results of multiplex PCR showed clonal rearrangements of both kappa and lambda immunoglobulin light chain genes. The findings of immunochemistry revealed that the lesion expressed lambda light chain, but not kappa light chain. Based on the clinical, pathologic, and molecular findings, this case was diagnosed as pulmonary MALT lymphoma. We report the first case in Korea of lambda-expressing MALT lymphoma that is shown to have dual clonal rearrangements of kappa and lambda immunoglobulin light chain gene by multiplex PCR.
Aged ; Female ; *Gene Rearrangement, B-Lymphocyte, Light Chain ; Humans ; Immunoglobulin kappa-Chains/*genetics ; Immunoglobulin lambda-Chains/*genetics ; Lymphoma, B-Cell, Marginal Zone/*diagnosis/genetics/pathology ; Polymerase Chain Reaction

OBJECTIVETo construct a personalized full-length fully human antibody mammalian display library for children with systemic lupus erythematosus (SLE).

METHODSThe total RNA was isolated from the PBMCs of SLE children. The heavy chain variable region and kappa light chain (VH and LCκ) of the antibody genes were amplified by RT-PCR and inserted into the pDGB-HC-TM vector separately to construct the heavy chain and light chain libraries. The library DNAs were transfected into 293T cells and the expression of full-length fully human antibody on the surface of 293T cells was analyzed by flow cytometry.

RESULTSUsing 0.8 µg total RNA as the template, the VH and LCκ were amplified and the full-length fully human antibody mammalian display library was constructed. The VH and LCκ gene libraries had a size of 9.4×10(4) and 8.4×10(4), respectively. Sequence analysis of 10 clones randomly selected from the VH and LCκ gene libraries each showed that 8 heavy chain clones and 7 light chain clones contained correct open reading frames, and flow cytometry demonstrated that all the 15 clones express full-length antibodies on 293T cell surfaces. 293T cells co-transfected with the VH and LCκ gene libraries expressed the full-length antibodies on the cell surface.

CONCLUSIONThe personalized full-length fully human antibody library for SLE children constructed allows display of the full-length antibodies on mammalian cell surfaces, thus providing a valuable platform for analyzing the autoantibodies, their etiological role, and their clinical implications in SLE.

Amino Acid Sequence ; Child ; Gene Library ; Genetic Vectors ; Humans ; Immunoglobulin Heavy Chains ; genetics ; Immunoglobulin kappa-Chains ; genetics ; Lupus Erythematosus, Systemic ; genetics ; immunology ; Membrane Proteins ; genetics

Humans ; Immunoglobulin Light Chains ; genetics ; immunology ; Immunoglobulin kappa-Chains ; genetics ; immunology ; Kidney ; immunology ; metabolism ; pathology ; Kidney Diseases ; immunology ; pathology ; therapy ; Mutation ; Transforming Growth Factor beta ; metabolism

The objective of this study was to explore the clinical significance of measuring serum free light chains (sFLC) and to compare with serum total light chains (free and binded) in multiple myeloma (MM). sFLC in 20 newly diagnosed MM patients and 20 cases of healthy people as control were measured by immuno-nephelometric assays; the serum light chains and kappa/lambda ratio were measured in all patients, while immunofixation electrophoresis (IFE) tests were carried out at the same time in 18 out of 20 patients. The results showed that the abnormality of serum free light chains and kappa/lambda ratio were found in all of the 20 newly diagnosed MM patients (p < 0.01). The measurement of sFLC showed higher sensitivity than the total serum chains (p < 0.01). It is concluded that the method testing sFLC by immuno-nephelometric assay combined with kappa/lambda ratio is valuable for MM diagnosis, and the measurement of sFLC can be used as one of indicators for MM diagnosis.
Adult ; Aged ; Biomarkers, Tumor ; blood ; Female ; Humans ; Immunoglobulin kappa-Chains ; blood ; Immunoglobulin lambda-Chains ; blood ; Male ; Middle Aged ; Multiple Myeloma ; blood