No abstract

Cellular immunophenotypic studies were performed on a cohort of randomly selected IgM+ B-chronic lymphocytic leukemia (B-CLL) cases for which Ig VH and VL gene sequences were available. The cases were categorized based on V gene mutation status and CD38 expression and analyzed for treatment history and survival. The B-CLL cases could be divided into 2 groups. Those patients with unmutated V genes displayed higher percentages of CD38+ B-CLL cells (≥30%) than those with mutated V genes that had lower percentages of CD38+ cells (<30%). Patients in both the unmutated and the ≥30% CD38+ groups responded poorly to continuous multiregimen chemotherapy (including fludarabine) and had shorter survival. In contrast, the mutated and the <30% CD38+ groups required minimal or no chemotherapy and had prolonged survival. These observations were true also for those patients who stratified to the Rai intermediate risk category. In the mutated and the <30% CD38+ groups, males and females were virtually equally distributed, whereas in the unmutated and the ≥30% CD38+ groups, a marked male predominance was found. Thus, Ig V gene mutation status and the percentages of CD38+B-CLL cells appear to be accurate predictors of clinical outcome in B-CLL patients. These parameters, especially CD38 expression that can be analyzed conveniently in most clinical laboratories, should be valuable adjuncts to the present staging systems for predicting the clinical course in individual B-CLL cases. Future evaluations of new therapeutic strategies and drugs should take into account the different natural histories of patients categorized in these manners.

Cellular immunophenotypic studies were performed on a cohort of randomly selected IgM+ B-chronic lymphocytic leukemia (B-CLL) cases for which Ig VH and VL gene sequences were available. The cases were categorized based on V gene mutation status and CD38 expression and analyzed for treatment history and survival. The B-CLL cases could be divided into 2 groups. Those patients with unmutated V genes displayed higher percentages of CD38+ B-CLL cells (≥30%) than those with mutated V genes that had lower percentages of CD38+ cells (&lt;30%). Patients in both the unmutated and the ≥30% CD38+ groups responded poorly to continuous multiregimen chemotherapy (including fludarabine) and had shorter survival. In contrast, the mutated and the &lt;30% CD38+ groups required minimal or no chemotherapy and had prolonged survival. These observations were true also for those patients who stratified to the Rai intermediate risk category. In the mutated and the &lt;30% CD38+ groups, males and females were virtually equally distributed, whereas in the unmutated and the ≥30% CD38+ groups, a marked male predominance was found. Thus, Ig V gene mutation status and the percentages of CD38+B-CLL cells appear to be accurate predictors of clinical outcome in B-CLL patients. These parameters, especially CD38 expression that can be analyzed conveniently in most clinical laboratories, should be valuable adjuncts to the present staging systems for predicting the clinical course in individual B-CLL cases. Future evaluations of new therapeutic strategies and drugs should take into account the different natural histories of patients categorized in these manners.

approved these studies. From a cohort of 237 patients with clinical and laboratory features of B-CLL, 25 patients with expansions of CD5 + /CD19 + B cells expressing surface membrane IgG or IgA were chosen and analyzed. All of the patients with surface membrane IgM + cells were obtained randomly; some of the IgG + cases were provided by others because of their surface membrane phenotype and therefore were not randomly acquired. Some patients and the V gene Nonstandard abbreviations used: arsonate (Ars); B cell antigen receptor (BCR); B cell chronic lymphocytic leukemia (B-CLL); double-stranded DNA (dsDNA); framework region (FR); germinal center (GC); heavy chain third complementarity-determining region (HCDR3); light chain third complementarity-determining region (LCDR3); single-stranded DNA (ssDNA); web antibody modeling (WAM).

IntroductionB-cell chronic lymphocytic leukemia (B-CLL) is a clonal disease of an apparently slowly dividing B lymphocyte that expresses a distinct cell surface phenotype (CD19 ϩ , CD5 ϩ , CD23 ϩ cells with diminished surface membrane immunoglobulin). 1 Subgroups of B-CLL exist, defined by differences in lymphocyte doubling times in vivo, 2 variable degrees of somatic mutation of the immunoglobulin V (Ig V)-region genes in the leukemic cells, 3,4 and expression of cell surface 5 and intracellular 6,7 proteins. Each of these subgroups is accompanied by significant differences in clinical course and outcome. 2,[6][7][8][9] Membership in one of these subgroups may reflect differences in the antigenic experiences of the precursor B cells (naive vs memory), the manner in which these precursor cells were triggered (T-cell dependently or T-cell independently), or the level of spontaneous or induced cell cycling. 10 Defining the relative importance of these issues may provide clues to the development and evolution of B-CLL.Telomere lengths can serve as indicators of the replicative history of individual cells because these chromosomal segments shorten with each cell division. 11 As a consequence of the inability to adequately maintain telomere length, a slow but inexorable decrease in a cell's replicative potential accompanies cellular division, 12,13 and is also part of the normal aging process. 14-16 Two processes counteract telomere shortening and restore telomeric regions in normal and transformed cells: the activity of the enzyme telomerase [17][18][19][20] and an alternative lengthening of telomere (ALT) pathway. 21,22 Of special note is the observation that during a classical T-cell-mediated germinal center (GC) reaction, normal B cells produce high levels of telomerase and exhibit telomere lengthening. [23][24][25][26] This process presumably permits those B lymphocytes that develop newly diversified and advantageous B-cell receptors to maintain viability and to participate further in adaptive immune responses.As observed in many solid 27 and hematologic 18-20 cancers, B-CLL cells have short telomere lengths. 28 In this study, we analyzed telomere length as a means to infer the number of cell divisions that individual leukemic lymphocytes underwent and the relationship between telomere length and telomerase activity in the same cells. We were especially interested in trying to define differences in telomere length between the 2 Ig V gene mutationdefined B-CLL subgroups and to decipher to what degree this shortening reflects preleukemic events compared with leukemic events. We found that B-CLL cells have shorter telomeres than B cells or isolated CD5 ϩ and CD5 Ϫ B cells from a group of healthy For personal use only. on May 9, 2018. by guest www.bloodjournal.org From subjects matched for age. Moreover, we identified differences in telomere length and telomerase activity within the 2 Ig V gene mutation B-CLL subgroups that possibly indicate different replicative and telomere restorative histories for the cells and ...

The accumulation of B lymphocyte clones in the cerebrospinal fluid (CSF) of patients with multiple sclerosis (MS) and patients with other neurological disorders was investigated using PCR technologies. Oligoclonal B cell accumulations were detected in 10 of 10 MS patients, but only in 3 of 10 of the patients with other neurological disorders. Analyses of the Ig V(D)J sequences on the CSF from MS patients disclosed that VH3 and VH4 genes were extensively mutated compared with germline sequences. Moreover, a substantial proportion of the molecular clones analyzed shared the same third CDR of the H chain variable region gene (HCDR3) and the same VH genes, albeit with different numbers and locations of point mutations, thus indicating an ongoing process of intraclonal diversification. A larger number of clonally related VH sequences could be obtained by using a VH3 gene-specific PCR so that genealogical trees depicting the process of diversification could be drawn. Analyses of the Ig V(D)J from the CSF of a patient with viral meningitis and oligoclonal B cell accumulations revealed that VH3 genes were extensively mutated. However, no intraclonal diversification could be observed even using VH3 gene-specific PCR methodologies. Clone-specific PCR and sequencing was used to detect the V(D)J found in the CSF of one MS patient in the PBL of the same patient. Only 1/3 of the V(D)J sequences investigated could be demonstrated in the PBL, indicating that the V(D)J genes utilized by B cells in the CSF are much less represented in the PBL. Collectively, the data suggest that in MS there is a compartmentalized clonal expansion.

approved these studies. From a cohort of 237 patients with clinical and laboratory features of B-CLL, 25 patients with expansions of CD5 + /CD19 + B cells expressing surface membrane IgG or IgA were chosen and analyzed. All of the patients with surface membrane IgM + cells were obtained randomly; some of the IgG + cases were provided by others because of their surface membrane phenotype and therefore were not randomly acquired. Some patients and the V gene Nonstandard abbreviations used: arsonate (Ars); B cell antigen receptor (BCR); B cell chronic lymphocytic leukemia (B-CLL); double-stranded DNA (dsDNA); framework region (FR); germinal center (GC); heavy chain third complementarity-determining region (HCDR3); light chain third complementarity-determining region (LCDR3); single-stranded DNA (ssDNA); web antibody modeling (WAM).

Progressive Myoclonus Epilepsies (PMEs) are a group of uncommon clinically and genetically heterogeneous disorders characterised by myoclonus, generalized epilepsy, and neurological deterioration, including dementia and ataxia. PMEs may have infancy, childhood, juvenile or adult onset, but usually present in late childhood or adolescence, at variance from epileptic encephalopathies, which start with polymorphic seizures in early infancy. Neurophysiologic recordings are suited to describe faithfully the time course of the shock-like muscle contractions which characterize myoclonus. A combination of positive and negative myoclonus is typical of PMEs. The gene defects for most PMEs (Unverricht-Lundborg disease, Lafora disease, several forms of neuronal ceroid lipofuscinoses, myoclonus epilepsy with ragged-red fibers [MERRF], and type 1 and 2 sialidoses) have been identified. PMEs are uncommon disorders, difficult to diagnose in the absence of extensive experience. Thus, aetiology is undetermined in many patients, despite the advance in molecular medicine. Treatment of PMEs remains essentially symptomaticof seizures and myoclonus, together with palliative, supportive, and rehabilitative measures. The response to therapy may initially be relatively favourable, afterwards however, seizures may become more frequent, and progressive neurologic decline occurs. The prognosis of a PME depends on the specific disease. The history of PMEs revealed that the international collaboration and sharing experience is the right way to proceed. This emerging picture and biological insights will allow us to find ways to provide the patients with meaningful treatment.