Jitendra N. Mehrishi

Electrophoresis of cells and the biological relevance of surface charge

Recent developments in electrophoresis of cells are reviewed. Problems and progress in automation and miniaturization of analytical electrophoresis instruments as well as in the interpretation of experimentally determined electrophoretic mobility (EPM) data are summarized: In recent times, the EPM determination techniques not only became more reliable and faster, but also more knowledge could be gained about the cell surface electrical properties, the structure of the glycocalyx as well as its influence on the cell peripheral regions and microenvironment by applying cell electrophoresis. In addition, ways are shown to solve discrepancies between physical requirements of a preparative cell electrophoresis procedure and the quantities of ions, which have to be dissolved in cell suspension media. As the modern machines allow the purification of untagged cells suspended in more cell friendly and physiological media, they are likely to be valuable tools in several useful practical applications in clinical transplantation, gene therapy and treatment of disease states.

Human red blood cell aging: correlative changes in surface charge and cell properties

Red blood cells (RBCs) during microcirculation, aging and storage, lose N‐acetylneuraminic acid (NANA) and other biomaterials thereby altering cell structures, some properties and functions. Such cell damage very likely underlies the serious adverse effects of blood transfusion. However, a controversy has remained since 1961–1977 as to whether with aging, the RBCs, suffering loss of NANA, do have a decreased charge density. Any correlation between the changes in the cell properties with cell aging is also not clear. Therefore, to remove the ambiguity and uncertainty, we carried out multiparameteric studies on Percoll fractions of blood of 38 volunteers (lightest‐young‐Y‐RBCs, densest‐old‐O‐RBCs, two middle fractions).We found that there were striking differences between the properties of Y‐RBCs and O‐RBCs. The ζ‐potential of Y‐RBCs decreased gradually with aging. Studies in parallel on RBC fractions incubated with both positively charged quantum dots and Sambucus Nigra‐fluorescein isothiocyanate (FITC) along with their ζ‐potentials provide for the first time direct visual evidence about the lesser amount of charge density and NANA on O‐RBCs, and a collinear decrease in their respective ζ‐potentials. Close correlation was found between the surface charge on an aging RBC and its structure and functions, from the cell morphology, the membrane deformability to the intracellular Hb structure and oxidation ability. This quantitative approach not only clarifies the picture but also has implications in biology and medicine.

The Lymphocyte Surface

Differences in the electrokinetic properties of thymocytes from A.CA (H-2f) and A.SW (H-2S) mice were observed, the anodic electrophoretic m

Surface Molecular Components of Human Lymphocytes

The presence of at least 5 different types of ionizable groups on the surface of normal human lymphocytes on a per-cell-basis has been established. Two possible arrangements of these groups have been put forward. These surface groups (positively and negatively charged) may provide a molecular basis for establishing differences, if any, between types of lymphocytes. The complex reactions taking place on the surface of lymphocytes involved in immune processes are of considerable interest in health and disease.

T Cells Survey the Stability of the Self: A Testable Hypothesis on the Homeostatic Role of TCR-MHC Interactions

In the lifetime of an individual, every single gene will have undergone mutation on about 1010 separate occasions. Nevertheless, cancer occurs mainly with advancing age. Here, we hypothesize that the evolutionary pressure driving the creation of the T cell receptor (TCR) repertoire was primarily the homeostatic surveillance of the genome. The subtly variable T cells may in fact constitute an evolutionary link between the invariable innate and hypervariable B cell systems. The new model is based on the homeostatic role of T cells, suggesting that molecular complementarity between the positively selected TCR and the self peptide-presenting major histocompatibility complex molecules establishes and regulates homeostasis, strictly limiting variations of its components. Notwithstanding, the ‘homeostatic role of T cells’ model offers a more realistic explanation as to how a naïve clonal immune system can cope with the much faster replicating pathogens, despite a limited repertoire that is capable of facing only a small fraction of the vast antigenic universe at a time.

Reduction in High Blood Tumor Necrosis Factor-α Levels After Manipulative Therapy in 2 Cervicogenic Headache Patients

OBJECTIVE This case report discusses the treatment of 2 patients with cervicogenic headache (CHA) attending the Outpatient Clinic of the Hungarian National Institute for Rheumatology and Physiotherapy (Budapest, Hungary) and reviews the pathophysiology, therapeutic strategy, and problems associated with the treatment of CHA. CLINICAL FEATURES Patient 1 was a 27-year-old female who sustained a whiplash injury. A sharp, shooting headache developed, readily induced, and aggravated by just bending the neck backward or by turning her head. Magnetic resonance imaging revealed a disk protrusion at C4-C5 pressing the anterior cerebrospinal space. Patient 2 was a 62-year-old female who sustained a whiplash injury; her cervical movements became restricted, which precipitated headaches. Magnetic resonance imaging revealed a paramedian disk hernia between the C4 and C5 vertebrae that intruded into the right ventral cerebrospinal space. INTERVENTION AND OUTCOME After 4 weeks of manipulative therapy for patient 1, both active and passive range of motion returned to normal, and the high tumor necrosis factor-alpha (TNF-alpha) level (63 pg/mL) was substantially reduced (28 pg/mL). Patient 2 was started on manipulative therapy twice a week for 4 weeks; after 2 months, the patient became symptom-free, and high TNF-alpha level (72 pg/mL) was reduced greatly (35 pg/mL). CONCLUSION Two patients with whiplash injury and disk herniation developed CHA associated with very high TNF-alpha levels. After manipulative therapy, these patients became symptom-free, and their TNF-alpha levels decreased substantially.

Some Aspects of Complementarity in the Immune System

The burden of this paper is the suggestion that the defence capacity of the immune system is rather limited. It cannot stand in readiness to deal with a practically endless diversity and abundance of microbes. In contrast to conventional thinking the current model proposes: (1) The core idea that cells of the immune system are basically and constantly interconnected with host cells (e.g., through TCR-MHC interactions) and that foreign antigens (peptides) may tend to obstruct such interactions. Peptides presented during a viral infection typically decrease complementarity between the structures that are the products of the major histocompatibility complex (MHC) genes (or other genes related to it) and T cells. The altered MHC profile exposes infected cells to a polyclonal immune attack from other T cells such that tissue destruction occurs in an allograft rejection-like fashion. This may explain why a substantial portion of T cell numbers is activated when only a small number of specific T cells is ‘obstructed’ from functioning by the presence of nonself peptides. (2) Phagocytes ‘see’ targets even in a non-immune host because complement distribution associated with polyreactive natural antibodies magnifies sensitization differences between pathogens and host cells. (3) There is only a probability that hypermutation will successfully change the genome in some B cell clones to produce high affinity antibodies that prevent the re-infection of the host by the same pathogen, but cannot conquer primary infections. (4) The history of the development of the immune responses suggests that during prolonged interaction between host and microbes in our natural habitat, carried on over many generations, the adaptive antibody population may facilitate the evolution of the natural antibody repertoire. The model predicts that microbes, which are not a part of the local environment, may invade the organism without significant resistance. The model is discussed in various interactions for survival in the context of infection and tumorigenicity.

A novel method of CD34+ cell separation from umbilical cord blood.

Umbilical cord blood (UCB) is rich in the heavily glycosylated CD34 antigen–bearing hematopoietic stem cells that are valuable for transplantation therapy of malignant and nonmalignant disease. CD34+ cell yields (0.13%‐0.25%‐0.3%) of mononuclear cells (UCMCs) isolated by anti‐CD34 monoclonal antibody (MoAb) on immunomagnetic particles (e.g., Miltenyi particles) are insufficient to treat adults.

Anti-CTLA-4 therapy may have mechanisms similar to those occurring in inherited human CTLA4 haploinsufficiency

The inhibitory anti-CTLA-4 antibody, ipilimumab, dramatically improved survival in a subgroup of metastatic melanoma patients. The majority, however, suffered autoimmune-related adverse events (irAEs), sometimes pathognomonic of acute graft-versus-host-disease (GVHD). This implies that the CTLA-4 blockade is not tumor specific. We make a risky but testable prediction: anti-CTLA-4 therapy may have mechanism similar to that occurring in inherited human CTLA-4 haploinsufficiency. If so, a therapeutic paradigm shift is required. The task is not desperately trying to put the genie back in the bottle by immune-suppressive treatments, but harnessing the immense forces liberated by the anti-CTLA-4 antibody blockade by pretargeting or dose adjustment.

Surface molecular components of Ehrlich ascites tumour cells

SummaryOn the surface of Ehrlich ascites tumour cells various types of ionizable groups are present-sulphydryl groups, positively charged amino groups and at least three types of anionogenic groups.The numbers of the surface groups has been calculated on a per cell basis and their relative contribution to the electrokinetic make up determined.Two possible arrangements for the distribution of the groups in the cell periphery have been proposed.The importance of the surface groups in radiobiology and the other associated phenomena involving the cell surface membrane has been considered. The difficulties of the interpretation of the electrokinetic data concerning the role of the surface charge as a basis for malignancy have been pointed out. Since the surface charge of tumour cells can be increased to high negative values by tumour growth promoting and tumour growth inhibiting polyanions, extreme need of caution in the interpretation of the data has been emphasized.ZusammenfassungAuf der Oberfläche der Ehrlich-Aszites-Tumorzellen findet man verschiedene Typen ionisierbarer Gruppen (Sulphydryl-Gruppen) positive geladene Aminogruppen und mindestens drei Typen negativ geladener Gruppen.Die Zahl der Oberflächengruppen wurde an Hand der Zellbasis und ihrer relativen Zuteilung zur elektrokinetischen Struktur festgestellt. Es wurden zwei Möglichkeiten vorgeschlagen, die Gruppen in der Zellperipherie zu verteilen.Die Bedeutung der Oberflächenmembran beteiligt sind, wurde erörtert. Außerdem die an der Oberflächenmembran beteiligt sind, wurde erörtert. Außerdem wurde die Schwierigkeit der Interpretation der elektrokinetischen Daten, die die Bedeutung der Oberflächenbeteiligung am Malignen betreffen, betont. Da die Oberflächenbeteiligung bei Anwendung von Tumorwachstums- oder hemmungspolyanionen zu hohen negativen Werten anwachsen kann, ist äußerste Vorsicht geboten.